Efficient isolation and proliferation of human adipose-derived mesenchymal stromal cells in xeno-free conditions.

Classical methods used for culture of adipose-derived mesenchymal stromal cells (ADSCs) use xenobiotic components, which may present a potential risk for biological contamination and/or elicit immunological reactions. Therefore, the aim of this study was to establish a xeno-free methodology for the isolation and proliferation of human ADSCs (hADSCs). hADSCs were isolated by enzymatic digestion or mechanical dissociation and cultured in the presence of fetal bovine serum or human platelet lysate. Proliferation curves were performed as a function of time from the cell culture and used to calculate the population doubling time. Immunophenotyping and differentiation tests were used to identify and characterize the hADSCs. Human ADSCs isolated and cultured in conventional or xenobiotic-free conditions peaked at different days but achieved similar maximum proliferation. The hADSCs differentiation ability was similar in all groups. The characterization of hADSCs by flow cytometry showed low contamination of the cultures by other cell types. The xenobiotic-free methodology described in this study is a feasible and reproducible alternative for isolation and proliferation of hADSCs. This methodology is in accordance with the recommendations of the National Health Surveillance Agency, which proposes avoidance of xenobiotic products.

Novel polymeric dressing to the treatment of infected chronic wound.

Natural rubber latex (NRL) is a natural polymer which has arisen large interest in the biomedical field, mostly, due to its ability to facilitate angiogenesis and therefore, tissue repair. Moxifloxacin (MXF) is a broad-spectrum antibiotic orally administrated. Considering the biological properties of the NRL and its ability to deliver a wide range of compounds, the present study aimed to develop a novel device for infected chronic wound treatment. MXF-loaded NRL was obtained by a casting method. The results demonstrated that the incorporation of MXF in NRL did not promote any molecular interaction, preserving the integrity of the compounds. The mechanical properties of the biomaterial did not show any significant change, indicating enough elasticity for dermal application. The microbiological assays confirmed the ability of the polymer to deliver the drug without influencing its pharmacological properties. Moreover, it has expressed activity against major bacterial strains presented in wound infections. Finally, the biomaterial shown biocompatibility from the in vitro study. Thus, the present work has shown that MXF-loaded NRL membrane is a promising biomaterial to infected wound treatment.

Animal models in chronic obstructive pulmonary disease-an overview.

ABSTRACT Chronic obstructive pulmonary disease (COPD) is characterized by progressive airway obstruction resultant from an augmented inflammatory response of the respiratory tract to noxious particles and gases. Previous reports present a number of different hypotheses about the etiology and pathophysiology of COPD. The generating mechanisms of the disease are subject of much speculation, and a series of questions and controversies among experts still remain. In this context, several experimental models have been proposed in order to broaden the knowledge on the pathophysiological characteristics of the disease, as well as the search for new therapeutic approaches for acute or chronically injured lung tissue. This review aims to present the main experimental models of COPD, more specifically emphysema, as well as to describe the main characteristics, advantages, disadvantages, possibilities of application, and potential contribution of each of these models for the knowledge on the pathophysiological aspects and to test new treatment options for obstructive lung diseases.

Methodologies and Applications of Proteomics for Study of Yeast Strains: An Update.

Yeasts are one of the mostly used microorganisms as models in several studies. A wide range of applications in different processes can be attributed to their intrinsic characteristics. They are eukaryotes and therefore valuable expression hosts that require elaborate post-translational modifications. Their arsenal of proteins has become a valuable biochemical tool for the catalysis of several reactions of great value to the food (beverages), pharmaceutical and energy industries. Currently, the main challenge in systemic yeast biology is the understanding of the expression, function and regulation of the protein pool encoded by such microorganisms. In this review, we will provide an overview of the proteomic methodologies used in the analysis of yeasts. This research focuses on the advantages and improvements in their most recent applications with an understanding of the functionality of the proteins of these microorganisms, as well as an update of the advances of methodologies employed in mass spectrometry.

Seroepidemiological analysis of toxoplasmosis in college students.

BACKGROUND: Toxoplasmosis is a zoonosis caused by an obligate intracellular parasite, Toxoplasma gondii, which affects warm-blooded animals including humans. Its prevalence rates usually vary in different regions of the planet. METHODS: In this study, an analysis of the seroprevalence of toxoplasmosis among Brazilian students was proposed by means of IgG specific antibodies detection. The presence of anti-Toxoplasma gondii antibodies by indirect fluorescent antibody test (IFAT) was also evaluated in order to compare it with enzyme-linked immunosorbent assay (ELISA) and to assess the use of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and o-phenylenediamine dihydrochloride chromogens. RESULTS: The IFAT method showed a seroprevalence of 22.3%. These results were similar to those obtained by ELISA (24.1%). The seroprevalence was directly estimated from the IgG avidity, which showed that in a sample of 112 students, three of them had acute infection, an incidence of 1.6% in the studied population. CONCLUSION: In this study, the use of different chromogenic substrates in immunoenzymatic ELISA assays did not display different sensitivity in the detection of T. gondii-reagent serum. The extrapolation of results to this population must be carefully considered, since the investigation was conducted on a reduced sample. However, it allows us to emphasize the importance of careful and well prepared studies to identify risk factors for toxoplasmosis, to adopt preventive measures and to offer guidance to at-risk populations about the disease.

Proposição de uma nova metodologia para isolamento e cultivo de células-tronco mesenquimais derivadas do tecido adiposo / A new methodology proposition for isolation and culture of adipose-derived mesenchymal stem cells

Introdução: As células-tronco mesenquimais (CTM) têm despertado interesse de vários grupos de pesquisa em função do grande potencial de aplicabilidade em terapia celular e medicina regenerativa. Nesse contexto, o tecido adiposo vem recebendo grande destaque como importante fonte para obtenção de CTM. Os protocolos utilizados atualmente para o isolamento das células-tronco derivadas do tecido adiposo (ADSC) empregam, de forma geral, o método de digestão enzimática com colagenase extraída de bactéria (Clostridium histolyticun), que pode conter contaminantes, como endotoxinas e outros peptídeos que, eventualmente, poderão resultar em reações adversas nos procedimentos de terapia celular em pacientes humanos. Objetivo: Pretendeu-se no presente estudo adequar e propor uma nova abordagem empregando a metodologia de dissociação mecânica para isolamento de CTM derivadas de tecido adiposo de ratos. Métodos: As células cultivadas foram analisadas quanto ao potencial de adesão, proliferação e tempo de duplicação celular, por meio de uma curva de crescimento. As células isoladas e cultivadas a partir do tecido adiposo foram também analisadas quanto ao potencial de diferenciação in vitro nas linhagens adipogênica, condrogênica e osteogênica. Resultados: Os resultados mostraram que o tempo de duplicação (velocidade de crescimento) da população celular isolada por dissociação mecânica é mais expressivo quando comparado com a técnica de digestão enzimática. As células isoladas do tecido adiposo apresentaram potencial de diferenciação nas linhagens osteogênica, condrogênica e adipogênica. Conclusão: Os resultados obtidos permitem concluir que a metodologia de dissociação mecânica apresenta-se como uma alternativa viável, de baixo custo e, como tal, extremamente promissora no sentido de permitir que a colagenase de origem bacteriana (Clostridium histolyticun) torne-se um componente prescindível para isolamento e cultivo de células provenientes do tecido adiposo.

Background: Mesenchymal stem cells (MSCs) have attracted interest of several research groups due to the large potential applicability in cell therapy and regenerative medicine. In this context, adipose tissue has received high profile as an important source in order to obtain MSC. The protocols currently suggested for the isolation and culture of adipose- -derived stem cells (ADSC) utilize, in general, the enzymatic digestion method with bacterial collagenase (Clostridium histolyticun) which may contain contaminants such as endotoxin and other peptides that eventually may result in adverse reactions in the cell therapy procedures in human patients. Objective: In this context, it was intended in this study to propose a new methodological approach of mechanical dissociation for isolating and culture of adipose-derived mesenchymal stem cells. Methods: The cultured cells were analyzed for potential adhesion, proliferation and cell doubling time, through a growth curve lineages The cells were also analyzed according to potential for differentiation in adipogenic, chondrogenic and osteogenic lineages. Results: The results showed that the doubling time of the cell population isolated by mechanical dissociation is faster when compared to the enzymatic digestion technique. The isolated cells from adipose tissues howed potential for differentiation in cell lineages osteogenic, adipogenic and chondrogenic. Conclusion: The obtained results allow us to conclude that the methodology of mechanical dissociation, presented in this paper, is a viable, low cost and therefore an extremely promising alternative in order to permit that the bacterial collagenase, from Clostridium histolyticun, become a dispensable component for isolation and cultivation of adipose-derived stem cells.

Seroepidemiological analysis of toxoplasmosis in college students

Background: Toxoplasmosis is a zoonosis caused by an obligate intracellular parasite, Toxoplasma gondii, which affects warm-blooded animals including humans. Its prevalence rates usually vary in different regions of the planet. Methods: In this study, an analysis of the seroprevalence of toxoplasmosis among Brazilian students was proposed by means of IgG specific antibodies detection. The presence of anti-Toxoplasma gondiiantibodies by indirect fluorescent antibody test (IFAT) was also evaluated in order to compare it with enzyme-linked immunosorbent assay (ELISA) and to assess the use of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and o-phenylenediamine dihydrochloride chromogens. Results: The IFAT method showed a seroprevalence of 22.3%. These results were similar to those obtained by ELISA (24.1%). The seroprevalence was directly estimated from the IgG avidity, which showed that in a sample of 112 students, three of them had acute infection, an incidence of 1.6% in the studied population. Conclusion: In this study, the use of different chromogenic substrates in immunoenzymatic ELISA assays did not display different sensitivity in the detection of T. gondii-reagent serum. The extrapolation of results to this population must be carefully considered, since the investigation was conducted on a reduced sample. However, it allows us to emphasize the importance of careful and well prepared studies to identify risk factors for toxoplasmosis, to adopt preventive measures and to offer guidance to at-risk populations about the disease.

Cell therapy in experimental model of inflammatory bowel disease / Terapia celular em modelo experimental de doença inflamatória intestinal

Inflammatory bowel disease, which mainly involves Crohn's disease and ulcerative rectocolitis, is an inflammatory condition of the mucosa that can afflict any segment of the gastrointestinal tract. Despite the fact that the existing therapies result in improvement in patient's symptomatology and quality of life, there is no curative treatment. Surgical treatment involves complex procedures associated with high morbidity and mortality rates. In this context, cell therapy with stem cells has emerged as a treatment with broad potential applicability. In this study, we intended to verify the efficacy of transplantation of adipose tissue-derived stem cells in rats with intestinal inflammation induced by trinitrobenzenesulfonic acid. The cell population was isolated from the adipose tissue of inguinal region of rats and processed for culture by mechanical dissociation. The animals were evaluated with respect to clinical and biochemical aspects, as well as by macroscopic, microscopic and histological analyses. In the experimental model of bowel inflammation by 2,4,6-trinitrobenzenesulfonic acid, the infusion of adipose tissue significantly reduced the presence of adhesions in the colon and adjacent organs and decreased the activity of myeloperoxidase, a marker of neutrophil infiltration in the injured mucosa. The results suggest that cell therapy with adipose tissue can promote and/or accelerate the regeneration of damaged intestinal mucosa. It is concluded that the presence of adhesions and the determination of myeloperoxidase activity provide indications that adipose tissue can promote and/or accelerate the regeneration of inflammatory bowel mucosa. (AU)

A Doença Inflamatória Intestinal (DII), consistindo principalmente da doença de Crohn e retocolite ulcerativa, é uma condição inflamatória da mucosa que pode acometer qualquer segmento do trato gastrointestinal. Apesar das terapias existentes resultarem na melhora dos sintomas e da qualidade de vida dos pacientes, não há nenhum tratamento curativo. O tratamento cirúrgico envolve procedimentos complexos associados a altas taxas de morbimortalidade. Neste contexto, a terapia celular com células-tronco desponta como opção de tratamento potencialmente promissora. Em função destes aspectos, pretendeu-se, no presente estudo, verificar a eficácia do transplante de células-tronco derivadas do tecido adiposo (ASC) em ratos com inflamação intestinal induzida por ácido trinitrobenzenosulfonico (TNBS). As ASCs foram obtidas por dissociação mecânica do tecido adiposo da região inguinal de ratos e processadas para cultivo. Os animais foram avaliados, considerando-se os aspectos clínicos e bioquímicos, além de análises macroscópica, microscópica e histológica. No modelo de inflamação intestinal induzida por TNBS, a infusão de ASCs reduziu significativamente a presença de aderências entre o cólon e órgãos adjacentes, bem como diminuiu a atividade da mieloperoxidase (MPO), um marcador da infiltração de neutrófilos na mucosa lesada. Os resultados obtidos permitem concluir que a terapia celular com ASCs pode promover e/ou acelerar o processo de regeneração da mucosa intestinal inflamada. (AU)