Alteraciones de la expresión génica en la infección por SARS-CoV-2 en distintos modelos de estudio / Alterations of gene expression in SARS-CoV-2 infection in different study models

Objetivo: La pandemia por SARS-CoV-2 ha supuesto un auténtico reto para el mundo científico debido a la rápida transmisión y elevada mortalidad que produce este nuevo coronavirus. La enfermedad asociada se ha denominado COVID-19 y abarca desde casos asintomáticos hasta graves que evolucionan rápidamente a síndrome de distrés respiratorio agudo, alteraciones multisistémicas y la muerte. La comunidad científica ha aunado esfuerzos para tratar de conocer mejor el proceso fisiopatológico de la infección con la intención de combatir de forma más eficaz la enfermedad. En este trabajo presentamos un estudio para conocer las alteraciones de la expresión génica provocadas por la infección. Metodología: Se han usado tres modelos de estudio distintos: cultivos de células epiteliales bronquiales, organoides de las vías respiratorias y muestras obtenidas de autopsias en pacientes, con y sin infección por SARS-CoV-2. Se han analizado los perfiles de expresión alterados por la infección en cada modelo, así como las categorías funcionales enriquecidas. Resultados: Solo 4 genes son comunes en los tres tipos de modelos de estudio, siendo el modelo de autopsias el más dispar. Dentro de los genes comunes en los modelos de cultivo celular y organoide de pulmón encontramos funciones relacionadas con procesos inflamatorios. Conclusiones: Los estudios in vitro son un buen modelo para tener una foto fija de las alteraciones en los patrones de infección, mientras que las autopsias no son un buen modelo debido al sesgo provocado por la necrosis. (AU)

Short summary: Three different study models have been used to study the gene expression profiles produced by SARS-CoV-2: bronchial epithelial cell cultures, airway organoids, and autopsy samples from patients with and without SARS-infection. CoV-2. Basis: The SARS-CoV-2 pandemic has been a real challenge for the scientific world due to the rapid transmission and high mortality caused by this new coronavirus. The associated disease has been named COVID-19 and ranges from asymptomatic to severe cases that rapidly progress to acute respiratory distress syndrome, multisystem disorders, and death. The scientific community has joined efforts to try to better understand the pathophysiological process of the infection with the intention of combating the disease more effectively. In this work we present a study to determine the alterations in gene expression caused by the infection. Methods: Three different study models have been used: bronchial epithelial cell cultures, airway organoids, and samples obtained from autopsies in patients with and without SARS-CoV-2 infection. The expression profiles altered by the infection in each model have been analyzed, as well as the functional categories enriched. Results: Only 4 genes are common in the three types of study models, the autopsy model being the most disparate. Within the common genes in cell and organoid culture models of the lung, we find functions related to inflammatory processes. Conclusions: In vitro studies are a good model to have a snapshot of alterations in infection patterns, while autopsies are not a good model due to bias caused by necrosis. (AU)

Inactivación del virus Zika con medio de transporte de ácidos nucleicos, potencialmente aplicable a muestras clínicas para el diagnóstico molecular de SARS-CoV-2 / Inactivation of Zika virus with nucleic acids transport media, potentially applicable to clinical samples for the molecular diagnosis of SARS-CoV-2

RESUMEN Introducción: Los medios de colecta de muestras clínicas con capacidad de desnaturalizar virus reducen los riesgos de contagio durante el transporte y procesamiento. Objetivo: Emplear el medio de transporte de ácidos nucleicos (TAN) en muestras de exudado nasofaríngeo colectadas para el diagnóstico de SARS-CoV-2. Métodos: Se realizó un estudio experimental para demostrar la capacidad del medio de inactivar la infectividad viral. Se tomó como modelo de virus envuelto el virus Zika (VZk), cuyo nivel de bioseguridad es 2. Se evaluó el desempeño clínico del medio TAN para el diagnóstico de SARS-CoV-2. Se empleó una cepa del VZk propagada en la línea celular Vero y, previo a la infección de las células, el VZk se puso en contacto a intervalos de tiempo diferentes (2; 15 y 30 min) con el medio TAN puro; y luego se realizaron diluciones seriadas (10-1-10-4). La inactivación viral se evaluó por RT-PCR, en el sobrenadante y células colectadas, al culminar el periodo de propagación. El desempeño clínico del medio TAN se estimó tomando como referencia el CITOSWAB® VTM, en 30 exudados nasofaríngeos colectados para diagnóstico de la infección por SARS-CoV-2. Resultados: El VZk preservó su infectividad a diluciones del inóculo ≥ 10-2, independientemente del tiempo de contacto. La sensibilidad y especificidad clínica del medio TAN para el diagnóstico de SARS-CoV-2 fueron del 100 %, respectivamente. Conclusiones: Los resultados sugieren que muestras clínicas positivas a VZk en diluciones ≤ 10-1 del medio TAN pueden ser manipuladas de forma segura, lo que pudiera aplicarse potencialmente al diagnóstico molecular del SARS-CoV-2.

ABSTRACT Introduction: Collection media of clinical samples with the capacity to denature viruses reduce the risk of contagion during transportation and processing. Objective: To use the nucleic acids transport media (NATM) in nasopharyngeal swab samples collected for the diagnosis of SARS-CoV-2. Methods: An experimental study was conducted to demonstrate the medium capacity to inactivate viral infectivity. Zika virus (ZIKV), of biosafety level 2, was used as an enveloped virus model. The clinical performance of the NATM for the diagnosis of SARS-CoV-2 was evaluated. A ZIKV strain propagated in the Vero cell line was used and, prior to cells infection, ZIKV was in contact at different intervals (2; 15, and 30 min) with pure NATM; subsequently, serial dilutions (10-1-10-4) were performed. Viral inactivation was evaluated by RT-PCR in the supernatant and the collected cells when the propagation period was completed. CITOSWAB® VTM was used as reference to estimate the clinical performance of the NATM in 30 nasopharyngeal swabs collected for the diagnosis of SARS-CoV-2 infection. Results: ZIKV remained infectious at inoculum dilutions of ≥ 10-2, regardless of contact time. Clinical specificity and sensitivity of the NATM for the diagnosis of SARS-CoV-2 were 100%, respectively. Conclusions: Results suggest that ZIKV positive clinical samples at dilutions ≤ 10-1 of the NATM can be safely handled, which could potentially be applied to the molecular diagnosis of SARS-CoV-2.

3D spheroid cell cultures and their role in bone regeneration: a systematic review / Cultivos de esferoides 3D y su papel en la regeneración ósea: una revisión sistemática

Abstract Recently, the 3D spheroid cell culture application has been extensively used in the treatment of bone defects. A wide variety of methodologies have been used, which has made the comparison of results complex. Therefore, this systematic review has two aims: (i) to perform an analysis focused on the role of 3D spheroid cell culture in bone regeneration strategies; and (ii) address the main challenges in clinical application. A search of the following keywords "3D cell culture", "spheroid", and "bone regeneration" was carried out in the PubMed, Scopus, and ScienceDirect databases and limited to the years 2010-2020. Studies were included if their primary objective was the behavior of cell aggregates to formed spheroids structures by different 3D cell culture techniques focused on the regeneration of bone tissue. To address the risk of bias for in vitro studies, the United States national toxicology program tool was applied, and descriptive statistics of the data were performed, with the SPSS V.22 program. A total of 16 studies were included, which met the established criteria corresponding to in vitro and in vitro/in vivo studies; most of these studies used stem cells for the 3D cell spheroids. The most often methods used for the 3D formation were low adherence surface and rotational methods, moreover, mesenchymal stem cells were the cell line most frequently used because of their regenerative potential in the field of bone tissue engineering. Although the advances in research on the potential use of 3D spheroids in bone regeneration have made great strides, the constant innovation in cell spheroid formation methodologies means that clinical application remains in the future as strategy for 3D tissue bioprinting.

Resumen Recientemente, la aplicación del cultivo 3D de esferoides se ha utilizado ampliamente en el tratamiento de defectos óseos. La variedad de metodologías para lograr los cultivos 3D de esferoides ha hecho compleja la comparación de resultados. Por tanto, esta revisión sistemática tiene dos objetivos: (i) realizar un análisis centrado en el papel de los cultivos 3D de esferoides en las estrategias de regeneración ósea; y (ii) abordar los principales desafíos en la aplicación clínica. Se realizó una búsqueda de las siguientes palabras clave "cultivo celular 3D", "esferoide" y "regeneración ósea" en las bases de datos PubMed, Scopus y ScienceDirect y se limitó a los años 2010-2020. Se incluyeron los estudios si su principal objetivo era el comportamiento de agregados celulares para generar las estructuras esferoidales desarrollados por diferentes técnicas de cultivo celular 3D enfocadas a la regeneración del tejido óseo. Para abordar el riesgo de sesgo de los estudios in vitro, se aplicó la herramienta del programa nacional de toxicología de Estados Unidos y se realizaron estadísticas descriptivas de los datos, con el programa SPSS V.22. Se incluyeron un total de 16 estudios, que cumplieron con los criterios establecidos correspondientes a estudios in vitro e in vitro/in vivo; la mayoría de estos estudios utilizaron células troncales para generar los esferoides celulares 3D. Los métodos más utilizados para la formación de los esferoides 3D fueron la superficie de baja adherencia y los métodos de rotación, asimismo, la línea celular de células troncales mesenquimales fueron las más utilizadas debido a su gran potencial regenerativo en el campo de la ingeniería de tejidos óseos. Aunque los avances en la investigación sobre el uso potencial de los cultivos celulares de esferoides 3D en la regeneración ósea han logrado grandes avances, la constante innovación en las metodologías de la generación de esferoides 3D deja claro que la aplicación clínica de estos permanecerá en el futuro como estrategia en la bioimpresión tisular.

Proposta de cultivo de fibroblastos primários a partir de pavilhões auriculares de camundongos Balb/c / Proposal for the cultivation of primary fibroblasts from auricular pavilions of Balb/c mice

The skin represents more than 15% of body weight and, as it is an important way of interacting with the environment, it is subject to different stimuli and aggressions. After an injury, numerous factors collectively activate the inflammatory response in order to destroy aggressive agents and orchestrate tissue repair. Among the main cells that make up the skin are dermal fibroblasts, and the adoption of experimental models that mirror the biological behavior of these cells is of fundamental importance for regenerative medicine. Primary fibroblasts are examples of easily cultured cells, which have a range of advantages compared to other types. The present study aimed to test previous models of primary fibroblasts culture from the ears of mice of the BALB/c lineage, in order to be used in future studies of compatibility of biomaterials aimed at tissue repair, among other applications. Our results demonstrated the cultivation of primary dermal fibroblasts with typical microscopic morphology, with fusiform or stellate contours, evident cytoplasmic processes and a rounded nucleus. Cell viability and growth, evaluated after 2-4-6-8-10-12 days, showed a growth peak between 6 and 8 days, decreasing after 10 days. There was also a positive correlation between the experimental groups and the period of time elapsed. In the intragroup comparison, statistically significant differences were observed between experimental groups and negative control. Our results allowed us to conclude that primary dermal fibroblasts can be cultured simply, quickly and at low cost, from the ears of BALB/c mice, being a viable model to be used in studies of repairing biomaterials

A pele representa mais de 15% do peso corpóreo e por ser importante via de interação com o meio ambiente, está sujeita a diferentes estímulos e agressões. Após uma lesão, inúmeros fatores ativam coletivamente a resposta inflamatória, a fim de destruir agentes agressores e orquestrar o reparo tecidual. Entre as principais células que compõem a pele estão os fibroblastos dérmicos, e a adoção de modelos experimentais que espelhem o comportamento biológico dessas células é de fundamental importância para a medicina regenerativa. Fibroblastos primários são exemplos de células facilmente cultiváveis, que apresentam uma gama de vantagens em comparação com outros tipos. O presente estudo se propôs testar modelos prévios de cultivo de fibroblastos primários a partir de pavilhões auriculares de camundongos da linhagem BALB/c, a fim de serem utilizados em futuros estudos de compatibilidade de biomateriais voltados ao reparo tecidual, entre outras aplicações. Nossos resultados demonstraram o cultivo de fibroblastos dérmicos primários de morfologia microscópica típica, com contornos fusiformes ou estrelados, prolongamentos citoplasmáticos evidentes e núcleo arredondado. A viabilidade e crescimento celular, avaliados após 2-4-6-8-10-12 dias, demonstrou pico de crescimento entre 6 e 8 dias, decaindo a partir de 10 dias. Observou-se ainda, uma correlação positiva entre os grupos experimentais e o período de tempo decorrido. Na comparação intragrupos, observou-se diferenças estatisticamente significantes entre grupos experimentais e controle negativo. Nossos resultados nos permitiram concluir que, fibroblastos dérmicos primários podem ser cultivados de modo simples, rápido e com baixo custo, a partir de pavilhões auriculares de camundongos BALB/c, sendo um modelo viável a ser empregado em estudos de com biomateriais reparadores

Variedades de cultivo de líquido amniótico para el diagnóstico in vitro de poliploidías / Amniotic fluid culture varietys for poliploydies in vitro diagnosis

RESUMEN Fundamento: El cultivo celular permite el análisis directo de las células vivas mediante un microscopio. El estudio de las células contenidas en el líquido amniótico, mediante técnicas de cultivo, detecta anomalías en número y morfología de los cromosomas, que pueden relacionarse con enfermedades genéticas. Objetivo: Caracterizar las variedades de cultivo de líquido amniótico para el diagnóstico in vitro de poliploidías. Metodología: Se realizó un estudio descriptivo transversal, en el Centro Provincial de Genética Médica de Camagüey, en el periodo de noviembre de 2016 a abril de 2018.La población de estudio estuvo constituida por 1571 muestras útiles de líquido amniótico obtenidas por amniocentesis, en gestantes en el segundo trimestre, evaluadas en consulta multidisciplinaria con criterios clínicos de estudios cromosómicos según lo establecido en el diagnóstico prenatal citogenético, previo consentimiento informado. Se utilizaron 20 mL de líquido amniótico para la siembra de células fetales, y se aplicaron tres variantes de cultivo abierto (directo, centrifugado y expandido). Se determinó el complemento cromosómico en cada variedad. Resultados: Predominó el complemento cromosómico normal. Las tetraploidías prevalecieron en el cultivo expandido. El índice mitótico fue similar en las tres variedades de cultivo y el cultivo directo tuvo el más bajo índice de poliploidías. Conclusiones: El cariotipo normal fue predominante. Las tetrapolidías fueron las alteraciones más frecuentes y prevalecieron en el cultivo expandido. En el cultivo directo se presentó el más bajo índice de errores inducidos in vitro.

ABSTRACT Background: Cell culture allows direct analysis of live cells under a microscope. The cell study contained in amniotic fluid, by culture techniques, detects abnormalities in chromosome number and morphology, which can be related to genetic diseases. Objective: To describe amniotic fluid culture strains for the in vitro diagnosis of polyploidy. Methodology: A cross-sectional descriptive study was conducted at the Camagüey Provincial Center of Medical Genetics, from November 2016 to April 2018.The study population consisted of 1571 useful amniotic fluid samples obtained by amniocentesis, in pregnant women in the second trimester, evaluated by multidisciplinary discussion with clinical criteria for chromosomal studies as established in the cytogenetic prenatal diagnosis, prior informed consent. 20 mL of amniotic fluid were used for fetal cell seeding, and three open culture strains (direct, centrifuged and expanded) were applied. Chromosomal complement was determined in each variety. Results: Normal chromosome complement was predominant. Tetraploidy prevailed in the expanded culture. The mitotic index was similar in the three culture strains and the direct culture had the lowest polyploidy index. Conclusions: Normal karyotype was predominant. Tetraploidy were the most frequent modifications and prevailed in the expanded culture. Direct culture had the lowest rate of the in vitro induced errors.

Obtención y caracterización de células madre mesenquimales adultas de la pulpa dental humana / Obtaining and characterizing adult mesenchymal stem cells from human dental pulp

El presente trabajo de investigación tiene como objetivo principal el aislar, expandir y caracterizar inmunofenotípicamente células madre mesenquimales de la pulpa dental humana, según los criterios mínimos propuestos por The International Society for Cellular Therapy (ISCT), como así también establecer la puesta a punto de las técnicas y protocolos de procedimientos para tal fin. Los cultivos fueron permanentemente monitoreados mediante microscopio invertido con contraste de fase y la inmunotipificación fue realizada por citometría de flujo (AU)

Perspectivas en investigación: células HEp-2 infectadas con EB's de Chlamydia trachomatis serovar 2 (VR-902B) / Chlamydia trachomatis: Research Perspectives. HEp-2 Cells Infected with EB's from Chlamydia trachomatis serovar 2 (VR-902B): Research Perspectives

Resumen Chlamydia trachomatis (C. trachomatis) es una bacteria Gram negativa inmóvil, caracterizada por ser un microorganismo intracelular obligado y por poseer un ciclo reproductivo en el que puede distinguirse una forma infecciosa extracelular metabólicamente inerte (cuerpo elemental - EB's), y una forma no infecciosa intracelular y activa (cuerpo reticulado - RB's). C trachomatis se caracteriza por causar infección en humanos, está relacionada con enfermedades de transmisión sexual e infecciones oculares; por lo que puede conllevar a secuelas de interés, si no se da un tratamiento oportuno. El objetivo de este estudio fue optimizar el modelo de infección de C. trachomatis en células HEp-2 con cuerpos elementales (EB's) de C. trachomatis serovar L2. Inicialmente, se establecieron las condiciones para el crecimiento adecuado de las células HEp-2 en tiempo y con una confluencia del 90%, para continuar con la optimización de un protocolo de infección. La infección fue confirmada a partir de la coloración con Giemsa permitiendo evaluar características morfológicas tanto de las células HEp-2 sin infectar e infectadas, y así mismo, de los cuerpos elementales de C. trachomatis. Finalmente, se corroboró la infección con la técnica de inmunofluorescencia directa que detecta la proteína de membrana MOMP de C. trachomatis. Tras los ensayos realizados se evidenció la presencia de cuerpos elementales próximos y dentro del citoplasma celular, así como células vacuoladas y daño celular causado por la infección.

Abstract Chlamydia trachomatis (C. Trachomatis) is a Gram negative unmoving bacterium, characterized by being an obligate intracellular microorganism and having a reproductive cycle in which a metabolically inactive extracellular infectious form (elementary body - EB's) can be distinguished from an intracellular active and non-infectious form (reticulated body - RB's). C trachomatis is characterized by causing infection in humans, is related to sexually transmitted diseases and eye infections, so it can lead to sequelae of interest if timely treatment is not given. The objective of this study was to optimize the infection model of C. trachomatis in HEp-2 cells with elementary bodies (EB's) of C. trachomatis serovar L2. Initially, the conditions for the adequate growth of HEp-2 cells were established in time and with a confluence of 90%, to continue with the optimization of an infection protocol. The infection was confirmed from the staining with Giemsa allowing to evaluate morphological characteristics of both uninfected and infected HEp-2 cells and also of the elementary bodies of C. trachomatis. Finally, the infection was corroborated with the direct immunofluorescence technique, that detects the C. trachomatis MOMP membrane protein. After the tests were performed, the presence of elementary bodies nearby and within the cellular cytoplasm was evidenced, as well as vacuolated cells and cellular damage caused by the infection.

Detección de un mosaico de trisomía 21 en líquido amniótico / Detection of a mosaicism of trisomy 21 in amniotic liquid

Resumen Se analizó un resultado con alteración cromosómica tomado de una base de datos conformada por un total de 4755 muestras de líquido amniótico extraídos mediante amniocentesis con indicación de su médico tratante, riesgo sérico y edad materna avanzada. En este reporte se presenta la detección de un mosaico de trisomía 21 en líquido amniótico, mediante la técnica de Banda G donde se analizaron 20 metafases. Los resultados obtenidos documentan una composición cromosómica 47, XY+21 y 46, XY con una relación 9:11 respecto a las metafases analizadas, confirmándose así el diagnóstico del Síndrome de Down secundario a mosaico.

Abstract A result with chromosomal alteration was analyzed from a database consisting of a total of 4755 samples of amniotic fluid extracted by amniocentesis with indication of the attending physician, serum risk and advanced maternal age. This report presents the detection of a mosaicism of trisomy 21 in amniotic fluid, using G- Banding where 20 metaphases were analyzed. The results obtained document a chromosomal composition 47, XY + 21 and 46, XY with a 9:11 ratio with respect to the metaphases analyzed, confirming the diagnosis of Down syndrome secondary to mosaicism.

Evolution of Avian coronavirus (AvCoV) in BHK-21 and VERO cells / Evolução de Coronavírus aviário (AvCoV) em células BHK-21 e VERO

Avian coronavirus (AvCoV) infects a range of tissues in chickens and several other avian species. Although the virus can be isolated in chicken embryos, only a few strains of the 6 genotypes/33 lineages can grow in cell lines, with the Beaudette strain (GI-1 lineage) being the most used for in vitro studies. Considering the differences between cell lines and chicken embryos as habitats for AvCoV, this study aimed to assess the diversity of the genes coding for the nonstructural protein 3 (nsp3) and spike envelope protein (S) after serial passages in BHK-21 and Vero cells. After 14 passages of an embryo-adapted Beaudette strain, the virus loads fluctuated in both cell lines, with the highest loads being 8.72 log genome copies/µL for Vero and 6.36 log genome copies/µL for BHK-21 cells. No polymorphisms were found for nsp3; regarding S, not only aa substitutions (Vero: 8th passage A150S, and 14th S150A; BHK-21: 4th S53F, 8th F53Y, and 8th S95R), but also minor variants could be detected on chromatograms with fluctuating intensities. As the regions of these aa substitutions are within the receptor-binding domain of S, it can be speculated that differences in cell receptors between Vero and BHK-21 cells and the speed of cell death led to the selection of different dominant strains, while the stability of nsp3 supports its function as a protease involved in AvCoV replication. In conclusion, AvCoV quasispecies evolution is influenced by the biological model under consideration, and a gradual transition is seen for minor and major variants.(AU)

O Coronavírus aviário AvCoV infecta uma variedade de tecidos de galinhas e de outras espécies aviárias. Apesar de este vírus poder ser isolado em ovos embrionados de galinha, apenas alguns dos 6 genótipos / 33 linhagens podem crescer em cultivo celular, sendo a cepa Beuadette (linhagem GI-11) a mais utilizada para estudos in vitro. Considerando as diferentes linhagens celulares e ovos embrionados como habitats para o AvCoV, este estudo teve por objetivo estudar a diversidade de genes que codificam para a proteína não-estrutural 3 (nsp3) e espícula (S) após passagens seriadas em células BHK-21 e VERO. Após 14 passagens, de uma amostra Beuadette adaptada a ovos embrionados, os títulos virais variaram em ambas as células, com os maiores títulos sendo de 8,72 log cópias genômicas/µL para Vero e 6,36 cópias genômicas/µL para BHK-21. Nenhum polimorfismo foi encontrando para nsp3. Considerando a proteína S, não somente foram encontradas substituições de aminoácidos (Vero: 8a passagem A150S e 14a passagem S150A; BHK-21: 4a passagem S53F, 8a passagem F53Y e S95R), mas também, variantes subconsensuais foram detectadas pelos cromatogramas com intensidades flutuantes. Uma vez que as regiões destes aa se encontram no domínio de ligação de receptor de S, pode-se especular que diferenças em receptores celulares entre Vero e BHK-21, além da velocidade da morte celular, levaram à seleção de diferentes cepas dominantes, enquanto que a estabilidade de nsp3 concorda com sua função como protease com papel na replicação de AvCoV. Como conclusão, a evolução de quase-espécies de AvCoV é influenciada pelo modelo biológico sob consideração e uma transição gradual é vista para variantes dominantes e subdominantes.(AU)

Estudo imuno-histoquímico e in vitro de proteínas do sistema ativador de plasminogênio em carcinomas de células escamosas de língua oral / Immunohistochemical and in vitro study of plasminogen activator system proteins in oral tongue squamous cell carcinomas

O carcinoma de células escamosas (CCE) é a neoplasia maligna mais frequente da cavidade oral e apresenta prognóstico desfavorável. Assim sendo, pesquisas têm buscado esclarecer o papel de biomarcadores no comportamento biológico do CCE oral. Nesta perspectiva, destacam-se o ativador de plasminogênio tipo uroquinase (uPA) e seu receptor (uPAR), além do inibidor do ativador de plasminogênio-1 (PAI-1). O presente trabalho analisou, por meio de imuno-histoquímica, a expressão das proteínas uPA, uPAR e PAI-1 no CCE de língua oral (CCELO) e sua relação com parâmetros clinicopatológicos. Este experimento também avaliou os efeitos in vitro da proteína recombinante humana PAI-1 (rhPAI-1) na linhagem celular SCC25, derivada de CCELO. A imunoexpressão de uPA, uPAR e PAI-1 foi analisada em 60 casos de CCELO, de forma semiquantitativa, nas células neoplásicas do front de invasão tumoral. Visando a associação dos achados imuno-histoquímicos com variáveis clinicopatológicas e taxas de sobrevida, os casos foram classificados nas categorias baixa expressão (≤50% das células positivas) e alta expressão (>50% das células positivas). No experimento in vitro, foram analisados os seguintes grupos: G0 (controle; células cultivadas na ausência de rhPAI-1), G10 (células tratadas com rhPAI-1 a 10 nM) e G20 (células tratadas com rhPAI-1 a 20 nM). Diferenças entre estes grupos foram investigadas através dos ensaios: viabilidade celular (Alamar Blue), ciclo celular (marcação com iodeto de propídio, PI), apoptose/necrose (marcação com Anexina V e PI), atividade migratória (Wound healing) e invasão celular (Transwell). A análise imuno-histoquímica revelou alta expressão do uPA na maioria dos CCELOs, mas sem relações significativas com parâmetros clinicopatológicos. As expressões do uPAR e do PAI-1, em nível membranar, foram associadas a recidivas locais (p=0,019) e ao elevado tumor budding (p=0,046), respectivamente. A expressão membranar do PAI-1 também apresentou associação significativa com o alto escore de risco histopatológico (p=0,043). A análise estatística evidenciou ausência de associações significativas entre as variáveis imunohistoquímicas (uPA, uPAR e PAI-1) e indicadores de prognóstico do CCELO (sobrevida específica e sobrevida livre da doença). No estudo in vitro, decorridas 24 horas da administração da rhPAI-1, os grupos G10 e G20 exibiram maior viabilidade celular em comparação ao grupo controle (p=0,020), assim como aumento da progressão para a fase S do ciclo celular (p=0,024). No que concerne aos percentuais de células apoptóticas e necróticas, não foram encontradas diferenças significativas entre os grupos. Nos grupos celulares cultivados na presença da rhPAI1, também foi constatado aumento da atividade migratória (p=0,039) e do potencial de invasão (p=0,039), respectivamente, nos intervalos de 24 horas e 72 horas. Os achados deste estudo sugerem o envolvimento das proteínas uPA, uPAR e PAI-1 na patogênese do CCELO. Entretanto, a expressão destes biomarcadores pode não estar relacionada com a sobrevida dos pacientes. Os resultados in vitro demonstram que o PAI-1 exerce efeitos estimulatórios na proliferação, migração e invasão celular, podendo assim contribuir para a agressividade biológica do CCELO (AU).

Squamous cell carcinoma (SCC) is the most frequent malignant neoplasm of the oral cavity and has an unfavorable prognosis. Thus, studies have sought to clarify the role of biomarkers in the biological behavior of oral SCC. Within this context, urokinase-type plasminogen activator (uPA) and its receptor (uPAR), as well as plasminogen activator inhibitor 1 (PAI-1), are particularly interesting. The present study analyzed, by means of immunohistochemistry, the expressions of uPA, uPAR and PAI-1 in oral tongue SCC (OTSCC) and their relationship with clinicopathological parameters. This experiment also evaluated the in vitro effects of recombinant human PAI-1 (rhPAI-1) on the OTSCC-derived cell line SCC-25. The immunoexpression of uPA, uPAR and PAI-1 was analyzed semiquantitatively in neoplastic cells of the invasion front of 60 OTSCC cases. Aiming to determine the association between immunohistochemical findings, clinicopathological variables and survival rates, the cases were classified as low expression (≤50% of positive cells) and high expression (>50% of positive cells). The following groups were analyzed in the in vitro experiment: G0 (control; cells cultured in the absence of rhPAI-1), G10 (cells treated with 10 nM rhPAI-1), and G20 (cells treated with 20 nM rhPAI-1). Differences between these groups were investigated using the following assays: cell viability (Alamar Blue), cell cycle (staining with propidium iodide, PI), apoptosis/necrosis (staining with Annexin V and PI), migratory activity (Wound healing), and cell invasion (Transwell). Immunohistochemical analysis revealed high expression of uPA in most OTSCC cases, but there were no significant associations with clinicopathological parameters. The high membrane expression of uPAR and PAI-1 was associated with local recurrence (p=0.019) and high tumor budding (p=0.046), respectively. Membrane expression of PAI-1 also presented a significant association with high-risk cases (p=0,043). Statistical analysis demonstrated no significant associations between the immunohistochemical variables (uPA, uPAR and PAI-1) and prognostic indicators of OTSCC (disease-specific and disease-free survival). In the in vitro experiment, 24 hours after administration of rhPAI-1, G10 and G20 exhibited greater cell viability compared to the control group (p=0.02), as well as increased progression to the S phase of the cell cycle (p=0.024). There were no significant differences in the percentages of apoptotic or necrotic cells between groups. In the groups cultured in the presence of rhPAI-1, migratory activity (p=0.039) and invasion potential (p=0.039) were found to be increased after 24 and 72 hours, respectively. The findings of this study suggest the involvement of uPA, uPAR and PAI-1 in the pathogenesis of OTSCC. Nevertheless, the expression of these biomarkers may not be related to survival of patients. The in vitro results suggest that PAI-1 exerts stimulatory effects on cell proliferation, migration and invasion and may therefore contribute to the biological aggressiveness of OTSCC (AU).

Efeitos do uso de dipeptídeos no cultivo de células CHO produtoras de anticorpo monoclonal / Effects of dipeptide use on monoclonal antibody- producing CHO cell culture.

The biopharmaceutical market has been growing steadily, thereby promoting the production of monoclonal antibodies for therapeutic purposes. As a consequence, the use of Chinese hamster ovary (CHO) cells, although already established, has been the focus of research in order to improve the production process. The use of dipeptides has been investigated as a promising proposal for supplementation of the culture medium, as they are metabolized slowly and potentially prevent the accumulation of ammonia in the medium, increasing both the productivity and the stability of the cells. In this project, CHO cells producing a monoclonal antibody were grown in a shaken flask in culture medium supplemented individually with dipeptides: alanyl-glutamine (AlaGln), glycyl-glutamine (GliGln), glycyl-tyrosine (GliTir) and acetyl-alanyl-glutamine (AcAlaGln), as possible glutamine substitutes. The effects of using these dipeptides were analyzed through a batch culture lasting 7 to 11 days. Cell growth, viability, productivity and concentration of substrates (glucose and glutamine) and byproducts (lactate and ammonia) were evaluated. Although the dipeptides increase the stability of cell culture and reduce the amount of lactate and ammonia produced, under the conditions of the experiments, it can be concluded that these molecules are not viable alternatives to the batch system to replace glutamine since they did not differ in the amount of monoclonal antibody produced.

O mercado biofarmacêutico vem crescendo incessantemente, alavancando a produção de anticorpos monoclonais para fins terapêuticos. Como consequência, o uso de células de ovário de hamster chinês (CHO), embora já estabelecido, vem sendo foco de pesquisas a fim de aperfeiçoar o processo produtivo. O uso de dipeptídeos têm sido investigado como uma proposta promissora de suplementação do meio de cultivo, pois são metabolizados lentamente e potencialmente evitam o acúmulo de amônia no meio, aumentando tanto a produtividade quanto a estabilidade das células. Neste projeto, células CHO produtoras de um anticorpo monoclonal foram cultivadas em frasco agitado em meio de cultivo suplementado individualmente com dipeptídeos: alanil-glutamina (AlaGln), glicil-glutamina (GliGln), glicil-tirosina (GliTir) e acetil-alanil-glutamina (AcAlaGln), como possíveis substitutos de glutamina. Os efeitos do uso destes dipeptídeos foram analisados através de um cultivo descontínuo com duração de 7 a 11 dias. Foram avaliados crescimento celular, viabilidade, produtividade e concentração de substratos (glicose e glutamina) e metabólitos (lactato e amônia). Apesar dos dipeptídeos aumentarem a estabilidade do cultivo e reduzirem a quantidade de lactato e amônia produzidos, nas condições dos experimentos, foi mostrado que estas moléculas não são alternativas viáveis para o sistema em batelada em substituição da glutamina uma vez que não diferiram na quantidade de anticorpo monoclonal produzido. Assim, considerando o sistema testado, o uso da glutamina continua sendo a melhor opção para este tipo de sistema com esta linhagem celular.

Collection and culture of human connective tissue cells from gingival explant technique for oral tissue bioengineering / Colección de células de tejido conectivo humano a partir de la técnica de explante gingival para bioingeniería de tejidos orales

SUMMARY: Cell culture is an important tool in medical, odontological and biological research laboratories, supporting cell therapies and tissue bioengineering strategies. Gingival fibroblasts present structural function, being able to modulate their metabolic capacity, which is reflected in the tissue morphology. The possibility of culturing fibroblasts in vitro, in monolayer or on three-dimensional scaffolds, for subsequent transplants in vivo opens important perspectives for the periodontal surgical clinic. The objective of the present article is to present a method of obtaining and cultivating viable human gingival fibroblasts for in vitro research. Explants derived from periodontal surgical discards were used, grown in 25 cm2 bottles to obtain a primary cell culture. After observing the proliferation and growth of the fibroblasts that interconnected and formed a monolayer network, involving the periphery of the explants, it was possible to remove the explants, to make the passage and the new subcultures were obtained in a ratio of 1:1. After 7 days, the amount of viable cells was analyzed in triplicate, using the Neubauer chamber technique, in cell culture bottles of 25 mm2 (T25) and 75 mm2 (T75). Fibroblasts were described and subclassified morphologically. The results showed a growth pattern in both bottles, but with a larger number in bottles of 75 cm2. Cells with fibroblastic morphology were subclassified into reticular and fusiform, being predominant those with fusiform morphology. In conclusion, culture of explant of human gingival connective tissue is a viable method for obtaining gingival connective tissue cells suitable for laboratory tests in cell culture, aiming at obtaining constructs for gingival tissue engineering.

RESUMEN: El cultivo celular es una herramienta importante en los laboratorios de investigación médica, odontológica y biológica, que apoyan las terapias celulares y las estrategias de bioingeniería de tejidos. Los fibroblastos gingivales presentan una función estructural, pudiendo modular su capacidad metabólica, que se refleja en la morfología tisular. La posibilidad de cultivar fibroblastos in vitro, en monocapa o en andamios tridimensionales, para trasplantes posteriores in vivo abre perspectivas importantes para la clínica de cirugía periodontal. El objetivo del presente artículo es presentar un método para obtener y cultivar fibroblastos gingivales humanos viables para investigación in vitro. Se utilizaron explantes derivados de los descartes quirúrgicos periodontales, crecidos en frascos de 25 cm2 para obtener un cultivo de células primarias. Después de observar la proliferación y el crecimiento de los fibroblastos que se interconectaron y formaron una red de monocapa, que involucraba la periferia de los explantes, fue posible eliminar los explantes, hacer el pasaje y los nuevos subcultivos se obtuvieron en una proporción de 1:1. Después de 7 días, la cantidad de células viables se analizó por triplicado, utilizando la técnica de cámara de Neubauer, en botellas de cultivo celular de 25 mm2 (T25) y 75 mm2 (T75). Los fibroblastos fueron descritos y sub-clasificados morfológicamente. Los resultados mostraron un patrón de crecimiento en ambas botellas, pero con un número mayor en botellas de 75 cm2. Las células con morfología fibroblástica se subclasificaron en reticulares y fusiformes, predominando aquellas con morfología fusiforme. En conclusión, el cultivo de explante de tejido conectivo gingival humano es un método viable para obtener células de tejido conectivo gingival adecuadas para pruebas de laboratorio en cultivos celulares, con el objetivo de obtener construcciones para la ingeniería del tejido gingival.

Infección por citomegalovirus humano en neonatos de un hospital público de Mérida, Yucatán.

INTRODUCTION: Human cytomegalovirus (HCMV) is recognized as the most common cause of congenital viral infection, which can occur as a result of primary infection, reinfection or infection reactivation in the pregnant woman and be the cause of delay in neuronal development and sensorineural hearing loss in the neonate. OBJECTIVE: To identify CMVH infection in newborns by real-time polymerase chain reaction (RT-PCR) and cell culture. METHOD: Observational, cross-sectional, retrospective study with oral swab samples from 362 neonates born within a 10-month period in a public hospital of Mérida, Yucatán. RT-PCR was carried out for the detection of HCMV. Fibroblast primary cell culture was obtained from human foreskin tissue to isolate the virus. Only positive cases were followed. RESULTS: A prevalence of HCMV infection of 0.86 % was found by RT-PCR. No virus was isolated with cell culture. In the follow-up visits, sensory health and neurodevelopment were adequate. CONCLUSION: The prevalence of HCMV infection is similar to that of worldwide reports, and only was detected by RT-PCR. Asymptomatic infection detected 12-14 h after birth had no long-term health consequences.

INTRODUCCIÓN: El citomegalovirus humano es reconocido como la causa más común de infección viral congénita, la cual puede darse como resultado de infección primaria, reinfección o reactivación en la mujer embarazada; además, puede ocasionar retraso en el desarrollo neuronal y pérdida auditiva sensoneural en el neonato. OBJETIVO: Identificar la infección por citomegalovirus humano en neonatos por PCR en tiempo real (PCR-TR) y cultivo celular. MÉTODO: Estudio observacional, longitudinal y retrospectivo con muestras de hisopado oral provenientes de 362 neonatos nacidos en un periodo de 10 meses en un hospital público de Mérida, Yucatán. Se realizó PCR-TR para la detección de citomegalovirus humano. Se obtuvo cultivo celular primario de fibroblastos a partir de tejido de prepucio humano para recuperar el virus. Se siguieron solo los casos positivos. RESULTADOS: Se encontró 0.86 % de infección por citomegalovirus humano por PCR-TR. No se recuperó el virus en cultivo. En las visitas de seguimiento, la salud sensorial y el neurodesarrollo fueron adecuados. CONCLUSIÓN: La prevalencia de infección por citomegalovirus humano en neonatos fue similar a la de reportes mundiales y solo pudo evidenciarse por PCR. La infección asintomática detectada entre las 12 a 24 horas del nacimiento no tuvo consecuencias a largo plazo.

Infección por citomegalovirus humano en neonatos de un hospital público de Mérida, Yucatán / Human cytomegalovirus infection in neonates from a public hospital in Mérida, Yucatán

Resumen Introducción: El citomegalovirus humano es reconocido como la causa más común de infección viral congénita, la cual puede darse como resultado de infección primaria, reinfección o reactivación en la mujer embarazada; además, puede ocasionar retraso en el desarrollo neuronal y pérdida auditiva sensoneural en el neonato. Objetivo: Identificar la infección por citomegalovirus humano en neonatos por PCR en tiempo real (PCR-TR) y cultivo celular. Método: Estudio observacional, longitudinal y retrospectivo con muestras de hisopado oral provenientes de 362 neonatos nacidos en un periodo de 10 meses en un hospital público de Mérida, Yucatán. Se realizó PCR-TR para la detección de citomegalovirus humano. Se obtuvo cultivo celular primario de fibroblastos a partir de tejido de prepucio humano para recuperar el virus. Se siguieron solo los casos positivos. Resultados: Se encontró 0.86 % de infección por citomegalovirus humano por PCR-TR. No se recuperó el virus en cultivo. En las visitas de seguimiento, la salud sensorial y el neurodesarrollo fueron adecuados. Conclusión: La prevalencia de infección por citomegalovirus humano en neonatos fue similar a la de reportes mundiales y solo pudo evidenciarse por PCR. La infección asintomática detectada entre las 12 a 24 horas del nacimiento no tuvo consecuencias a largo plazo.

Abstract Introduction: Human cytomegalovirus (HCMV) is recognized as the most common cause of congenital viral infection, which can occur as a result of primary infection, reinfection or infection reactivation in the pregnant woman and be the cause of delay in neuronal development and sensorineural hearing loss in the neonate. Objective: To identify CMVH infection in newborns by real-time polymerase chain reaction (RT-PCR) and cell culture. Method: Observational, cross-sectional, retrospective study with oral swab samples from 362 neonates born within a 10-month period in a public hospital of Mérida, Yucatán. RT-PCR was carried out for the detection of HCMV. Fibroblast primary cell culture was obtained from human foreskin tissue to isolate the virus. Only positive cases were followed. Results: A prevalence of HCMV infection of 0.86 % was found by RT-PCR. No virus was isolated with cell culture. In the follow-up visits, sensory health and neurodevelopment were adequate. Conclusion: The prevalence of HCMV infection is similar to that of worldwide reports, and only was detected by RT-PCR. Asymptomatic infection detected 12-14 h after birth had no long-term health consequences.

Metalloproteinase 11, potential marker and molecular target in advanced and castration-resistant prostate cancer. Culture study of peritumoral fibroblasts. / Metaloproteinasa 11, potencial marcador y diana molecular en cáncer de próstata avanzado y resistente a la castración. Estudio en cultivo de fibroblastos peritumorales.

OBJECTIVE: To analyze the expression of metalloprotein 11 (MMP11) in cultured fibroblasts obtained from human prostate tumors with different clinical and pathological characteristics. MATERIAL AND METHODS: For this study we analyzed samples of transrectal prostate biopsies from tumors with different characteristics, treated with or whithout androgen deprivation (AD). After optimization of the culture method, fibroblasts were isolated and cultured to perform the study (PCR) of MMP11 mRNA. RESULTS: Finally, 37 cases were studied: 5 samples of benign prostatic hyperplasia, 14 cases with localized neoplasms (7 high-risk according to the D'Amico classification), 5 with metastasic tumors (bone metastases), and 13 treated with AD therapy, of which 6 fulfilled the requirements to be defined as resistant to castration. In tumors without AD therapy, MMP11 expression was significantly higher (P=.001) in fibroblasts of higher grade tumors. A significant (P=.001) correlation was found between PSA and expression of MMP11 in fibroblast s and a significant increase of MMP11 expression in metastatic tumors. In tumors with AD therapy, a significantly greater expression of MMP11 was observed in resistant to castration patients than in those sensitive to castration (P=.003). CONCLUSION: In advanced prostate tumors or in stages of increased tumor aggressiveness, the production of MMP11 by fibroblasts is significantly greater than in non-metastatic tumors or in AD sensitive tumors.

Circovírus suíno 2b: isolamento e taxa de mutação em linhagem de célula de macrófagos (J744) / Porcine circovirus 2b: isolations and mutation rate in J744 lineage macrophage cell

Porcine circovirus 2 (PCV2) is associated with various clinical signs that are collectively designated as Circovirosis and has a great impact on the pig industry. The virus isolation is classically performed on PK-15 cell line, but other cells have been tested. Despite advances in studies with PCV2, isolation is still a challenge. The difficulty of maintaining these cell lines commonly used associated with the use of toxic substances to the isolation of PCV2 had stimulated the present study, that had the objectives to describe the first isolation of PCV2b in macrophage cell lines, J744 and verify the mutation rate at this system. A sample of lung was pooled and submitted to sequencing in which was classified in genotype PCV2b. This sample was used to inoculate a bottle of J744 with 30% of confluence in RPMI with 10% fetal bovine serum and submitted to five passages, which were accompanied by chain reaction quantitative polymerase (PCRq). The initial and final viral loads were 2.90 × 103 and 4.45 × 108 DNA copies/µL for PCV2b, respectively. Sequencing confirmed the isolation and had eliminated possible co-isolation of more than one genotype. After five passages, the isolate showed 99.7% identity with description of five point of non-synonymous or/and synonymous mutations observed in the cap and rep gene. The results demonstrate that J744 cells exhibit susceptibility, and the instability of the virus in J744 will be important for understanding the virus.

Porcine circovirus 2 (PCV2) está associado a vários sinais clínicos que são designados coletivamente como Circovirose e tem grande impacto na suinocultura. O isolamento viral é classicamente realizado em células da linhagem PK-15, contudo outras células têm sido testadas. Apesar dos avanços nos estudos com PCV2, o isolamento ainda é um desafio. Diante da dificuldade de manutenção dessas linhagens celulares comumente utilizadas associadas à necessidade do uso de substâncias tóxicas para o isolamento de PCV2, os objetivos do presente trabalho foram descrever o primeiro isolamento de Porcine circovirus 2b em linhagens de células de macrófago (J744) e verificar a taxa de mutação nesse sistema. Uma amostra de pulmão foi submetida ao sequenciamento e agrupada ao genótipo PCV2b. Essa amostra foi utilizada para inocular uma garrafa de J744 (com 30% de confluência em meio RPMI com 10% de soro fetal bovino) e submetida a cinco passagens, as quais foram acompanhadas por reação em cadeia da polimerase quantitativa (PCRq). As cargas virais inicial e final foram de 2,90 × 103 e de 4,45 × 108 cópias de DNA/µL para PCV2b, respectivamente. O sequenciamento confirmou o isolamento e descartou o coisolamento de mais de um genótipo. Após cinco passagens, o isolado apresentou identidade de 99,7%, com descrição de cinco mutações pontuais, uma sinônima e quatro não sinônimas, observadas nas regiões do gene cap e rep. Os resultados obtidos demonstram que as células J744 apresentam a susceptibilidade, e a instabilidade do vírus em J744 será importante para a compreensão do vírus.

Circovírus suíno 2b: isolamento e taxa de mutação em linhagem de célula de macrófagos (J744) / Porcine circovirus 2b: isolations and mutation rate in J744 lineage macrophage cell

Porcine circovirus 2 (PCV2) está associado a vários sinais clínicos que são designados coletivamente como Circovirose e tem grande impacto na suinocultura. O isolamento viral é classicamente realizado em células da linhagem PK-15, contudo outras células têm sido testadas. Apesar dos avanços nos estudos com PCV2, o isolamento ainda é um desafio. Diante da dificuldade de manutenção dessas linhagens celulares comumente utilizadas associadas à necessidade do uso de substâncias tóxicas para o isolamento de PCV2, os objetivos do presente trabalho foram descrever o primeiro isolamento de Porcine circovirus 2b em linhagens de células de macrófago (J744) e verificar a taxa de mutação nesse sistema. Uma amostra de pulmão foi submetida ao sequenciamento e agrupada ao genótipo PCV2b. Essa amostra foi utilizada para inocular uma garrafa de J744 (com 30% de confluência em meio RPMI com 10% de soro fetal bovino) e submetida a cinco passagens, as quais foram acompanhadas por reação em cadeia da polimerase quantitativa (PCRq). As cargas virais inicial e final foram de 2,90 × 103 e de 4,45 × 108 cópias de DNA/µL para PCV2b, respectivamente. O sequenciamento confirmou o isolamento e descartou o coisolamento de mais de um genótipo. Após cinco passagens, o isolado apresentou identidade de 99,7%, com descrição de cinco mutações pontuais, uma sinônima e quatro não sinônimas, observadas nas regiões do gene cap e rep. Os resultados obtidos demonstram que as células J744 apresentam a susceptibilidade, e a instabilidade do vírus em J744 será importante para a compreensão do vírus.(AU)

Porcine circovirus 2 (PCV2) is associated with various clinical signs that are collectively designated as Circovirosis and has a great impact on the pig industry. The virus isolation is classically performed on PK-15 cell line, but other cells have been tested. Despite advances in studies with PCV2, isolation is still a challenge. The difficulty of maintaining these cell lines commonly used associated with the use of toxic substances to the isolation of PCV2 had stimulated the present study, that had the objectives to describe the first isolation of PCV2b in macrophage cell lines, J744 and verify the mutation rate at this system. A sample of lung was pooled and submitted to sequencing in which was classified in genotype PCV2b. This sample was used to inoculate a bottle of J744 with 30% of confluence in RPMI with 10% fetal bovine serum and submitted to five passages, which were accompanied by chain reaction quantitative polymerase (PCRq). The initial and final viral loads were 2.90 × 103 and 4.45 × 108 DNA copies/µL for PCV2b, respectively. Sequencing confirmed the isolation and had eliminated possible co-isolation of more than one genotype. After five passages, the isolate showed 99.7% identity with description of five point of non-synonymous or/and synonymous mutations observed in the cap and rep gene. The results demonstrate that J744 cells exhibit susceptibility, and the instability of the virus in J744 will be important for understanding the virus.(AU)

El adipocito en el laboratorio: historia, perspectivas y reporte de experiencia / The adipocyte in the laboratory: history, perspectives and report of experience

Introducción: el tejido adiposo humano está compuesto por diferentes tipos celulares, y ha sido objeto de múltiples estudios en los últimos años debido a su acción en diversas funciones. Métodos: se realizó una búsqueda bilbiográfica en PubMed, Scielo, Science Direct and Google Scholars y se reporta la experiencia de los autores. Resultados: los primeros modelos de estudio fueron con tejido de roedores, y permitieron la comprensión del metabolismo de carbohidratos y ácidos grasos y facilitaron el estudio de la biología del adipocito, junto a estudios histológicos y el aislamiento de adipocitos maduros. Posteriormente se realizaron estudios con células precursoras (preadipocitos) que propiciaron el aislamiento de la línea celular 3T3-1L murina. En Latinoamérica, se han realizado diversos estudios con líneas celulares y con células madre mesenquimales precursoras de adipocitos para estudiar el efecto de hormonas y otras sustancias y para genotipificación. En Colombia se han realizado estudios con adipocitos 3T3-L1 para determinar los efectos de medicamentos y sustancias en estas células. En el laboratorio de Fisiología Celular de la Universidad Tecnológica de Pereira el proceso de obtención de muestras ha evidenciado dificultades por tratarse de tejido humano, pero el protocolo de aislamiento y cultivo pudo ser estandarizado a lo largo de seis años de experimentación; se aislaron preadipocitos y adipocitos maduros que permitieron estudiar los efectos de hormonas, realizar caracterización electrofisiológica y estudiar la fisiología del calcio. Conclusiones: este es un campo de investigación muy relevante debido a la implicación de este tipo celular en funciones metabólicas sistémicas y su relación con patologías de alta prevalencia como la obesidad y el síndrome metabólico.

Introduction: The human adipose tissue is composed of different cell types. It has been subject of several studies in the past years due to its role on diverse functions. Methods: A search in the PubMed, Scielo, Science direct and Google Scholars databases was performed and the authors experience was reported. Results: The first model used was rodent fat, which allowed a better comprehension on carbohydrate and fatty acid metabolism and enhanced research in adipocyte cell biology in addition with histological studies and mature adipocyte isolation. Afterwards, learning about precursor cell (pre-adipocytes) promoted the isolation of murine 3T3-L1 cell line. In Latin America research has been conducted using cell lines and adipocyte precursor mesenchymal stem cells to describe effects of hormones and perform DNA sequencing. In Colombia, studies in 3T3-L1 cell line aimed to stablish the effects of different compounds on these cells. In the Cell Physiology Laboratory of the Universidad Tecnológica de Pereira, sample collection process has shown difficulties because the source was human tissue; nevertheless isolation and cell culture protocols were standardized throughout the last six years of experimentation. Pre-adipocytes and mature adipocytes were isolated to study the effects of hormones, perform electrophysiological characterization and study calcium physiology. Conclusions: This is a relevant research field since these cells have important systemic metabolic functions and they have a clear relationship with high-prevalence pathologies such as obesity and the metabolic syndrome.

Isolation, expansion and differentiation of cellular progenitors obtained from dental pulp of agouti (Dasyprocta prymnolopha Wagler, 1831) / Isolamento, expansão e diferenciação de progenitors celulares obtidos da polpa dentária de cutia (Dasyprocta prymnolopha Wagler, 1831)

The study aimed to isolate, expand, differentiate and characterize progenitor cells existent in the dental pulp of agouti. The material was washed with PBS solution and dissociated mechanically with the aid of a scalpel blade on plates containing culture medium D-MEM/F-12, and incubated at 5% CO2-37⁰C. The growth curve, CFU assay, osteogenic/adipogenic differentiation and characterization were obtained from the isolation. The cells began to be released from the explant tissue around the 7th day of culture. By day 22 of culture, cells reached 80% confluence. At the UFC test, 81 colonies were counted with 12 days of cultivation. The growth curves before and after freezing showed a regular growth with intense proliferation and clonogenic potential. The cell differentiation showed formation of osteoblasts and fat in culture, starting at 15 days of culture in a specific medium. Flow cytometry (FACs) was as follows: CD34 (positive), CD14 (negative), CD45 (negative), CD73 (positive), CD79 (negative), CD90 (positive), CD105 (positive), demonstrating high specificity and commitment of isolated cells with mesenchymal stem cells strains. These results suggest the existence of a cell population of stem cells with mesenchymal features from the isolated tissue in the explants of agouti dental pulp, a potential model for study of stem cell strains obtained from the pulp tissue.

Isolation, expansion and differentiation of cellular progenitors obtained from dental pulp of agouti (Dasyprocta prymnolopha Wagler, 1831). Este estudo teve como objetivo isolar, expandir, diferenciar e caracterizar células progenitoras existentes na polpa dentária de cutia. O material foi lavado em solução de PBS e dissociado mecanicamente, com o auxílio de uma lâmina de bisturi, em placas contendo meio de cultura D-MEM/F-12, e incubadas em 5% de CO2-37⁰C. A curva de crescimento, o ensaio de CFU, a diferenciação osteogênica/adipogênica e a caracterização foram obtidas a partir do isolamento. As células começaram a ser liberadas, a partir do explante, em torno do sétimo dia de cultura. A partir do 22o dia, as células atingiram 80% de confluência. No teste para UFC, 81 colônias foram contadas aos 12 dias de cultivo. As curvas de crescimento pré- e pós-congelamento apresentaram crescimento regular, com intensa proliferação e potencial clonogênico. A diferenciação das células mostrou a formação de osteoblastos e de células de gordura, a partir de 15 dias de cultura em meio específico. A citometria de fluxo (FACS) apresentou-se como segue: CD34 (positivo), CD14 (negativo), CD45 (negativo), CD73 (positivo), CD79 (negativo), CD90 (positivo), CD105 (positivo), demonstrando a grande especificidade e comprometimento das células isoladas com linhagens de células-tronco mesenquimais. Estes resultados sugerem a existência de uma população de células-tronco mesenquimais isolada a partir de explantes da polpa dentária cutia, um modelo potencial para o estudo de linhagens de células-tronco obtidas a partir do tecido pulpar.

Comparación del cultivo celular de HeLa y HEp-2: Perspectivas de estudios con Chlamydia trachomatis / Comparison of cell culture HeLa and HEp-2: Studies prospects Chlamydia trachomatis

Objetivo. Estandarizar el cultivo de células HeLa en diferentes condiciones, con el fin de utilizarlo en protocolos de infección con Chlamydia trachomatis serovar L2. Materiales y métodos. Este estudio se llevó a cabo en cuatro fases principales que son: 1.Viabilidad celular por la técnica de azul de tripán y su posterior observación, 2. Estandarización del cultivo de células HeLa, 3. Coloración de Giemsa, 4. Cultivo de células HEp-2.Resultados. Se determinó que la línea celular HeLa debe ser cultivada en medio DMEM, 0,1% de L- glutamina, 10% de SFB. Así mismo, que la coloración de Giemsa es mejor realizarla en un tiempo de 40 minutos por que se evidencia una clara definición de núcleo y citoplasma. Frente a la comparación de las dos líneas celulares se obtuvo que la línea HeLa desde el primer día muestra un crecimiento adecuado y alcanza rápidamente la confluencia esperada, en contraposición la línea HEp-2 presenta un crecimiento más lento pero alcanzando la confluencia deseada al último día.

Objective. The goal of this study was to standardize the cultivation of HeLa cells under different conditions, to be used in Chlamydia trachomatis serovar L2 infection's protocols. Materials and Methods. This study was conducted in four phases that are: 1.Cell Viabilidad by trypan blue technique and his subsequent remark, 2. Standardization HeLa cell culture, 3. Giemsa, 4. Cultivation of Hep-2 cells. Results. As a result of standardization it is determined that the HeLa cell line should be cultured in DMEM, 0.1% L-glutamine, 10% FBS.It was determined that the Giemsa perform better over time of 40 minutes that a clear definition of nucleus and cytoplasm is evident. Comparing against both cell lines HeLa was obtained that the line from day growing well and quickly reaches the expected confluence, the opposed line HEp-2 has a slower growth but achieving the desired confluence the last day.