Production of dendritic cell vaccines using different methods with equivalent results: Implications for emerging centers

Introduction Dendritic cell (DC) vaccines have demonstrated good efficacy in preventing relapse and in increasing survival of patients affected by a variety of both solid and hematological tumors. Most protocols used to generate these cells involve the automated separation of peripheral blood monocytes from patients. This approach requires specialized equipment, which elevates the cost of this type of therapy, potentially limiting the widespread access to patients. Method: In this study, we compare the yield and quality of dendritic cells generated from monocytes and isolated by an automated method or by manual methods using gradient centrifugation. Results The results demonstrate the equivalence of the 3 methods in relation to the yield and final quality of the product, however with considerable differences between the costs of these procedures. In addition, this study also demonstrates the feasibility of the antigenic pulse with autologous tumor cell lysates, constituting a source of antigens, not only easily obtained and manipulated, but also specific to the patient's tumor. Conclusion These findings may have important implications for emerging centers interested in using this medical approach and potentially increase the access of a greater number of patients to this therapeutic option.

Development and verification of multiplex fluorescent quantitative PCR for detection of bacteria and fungi in cell culture medium / 中国生物制品学杂志

@#Objective To develop and verify a multiplex fluorescent quantitative PCR method for detection of common bacterial and fungal contaminants in cell culture medium.Methods According to NUC gene of Staphylococcus aureus,COLA gene of Clostridium spore,ITS-2 segment sequence of Candida albicans,a set of primers and probes were designed for each respectively,and using UBI3 gene of capsicum introduced as external standard gene,a triple reaction system of Staphylococcus aureus,Clostridium spore and external standard gene and a double reaction system of Candida albicans and external standard gene were established.The primer specificity,linear range,limit of detection,specificity,anti-interference performance and precision of the method were verified.Finally,100 samples of 293T cell culture medium were detected by using the developed method,which was compared with the common PCR method.Results Three pairs of primers all amplified about 100 bp specific gene bands corresponding to the three strains at different annealing temperatures(56,57,58 and59 ℃),and the size was consistent with the expected.In the range of 5.80 × 10~6 — 5.80 × 10~2 copies/μL,the standard plasmids of the three strains showed a good linear relationship with the Ct values.The standard curve equations were:Y=-3.373 X+37.48,Y=-3.557X+36.59 and Y=-3.536 X+39.78,each R~2> 0.99,respectively,and the amplification efficiency was in the range of 90%—110%.All the limits of detection of the three strains were 10~1 CFU/mL.The primers and probes of the three strains showed no specific amplification on the genomic DNA of six kinds of cells that were prone to cross-reaction.The genomic DNA of 293T cells,Yeast,Escherichia coli and Mycoplasma sp.had no effect on the detection.The CVs of repeatability and intermediate precision verification were both less than 15%.Among 100 cell culture medium samples,14 positive and 86 negative samples were detected,and the results of common PCR method for three positive and two negative samples randomly selected were consistent with the developed method.Conclusion The multiplex fluorescent quantitative PCR method developed in this study for the detection of bacteria and fungi in cell culture medium has good specificity,anti-interference performance and precision,and is simple to operate with low cost and high sensitivity,which can quickly detect the contaminants during cell culture.

Expression and significance of cyclin dependent kinase inhibitor 3 in HPV16-positive cervical cancer / 重庆医学

Objective To investigate the expression and significance of cyclin dependent kinase inhibitor 3(CDKN3)in human papillomavirus type 16(HPV16)-positive cervical cancer.Methods CDKN3 expression in pan-cancer was retrieved and downloaded from the Gene Expression Profiling Interactive Analysis(GEPIA)platform,and the expression levels of CDKN3 between normal cervical tissues(13 samples)and cervical cancer tissues(306 samples)were compared.Subsequently,GSE39001 data of HPV16-positive cervical cancer was sourced and downloaded from the Gene Expression Omnibus(GEO)database,and the expression levels of CDKN3 mRNA in HPV16-positive cervical cancer tissues(43 samples)and normal cervical tissues(12 samples)were compared.Immunohistochemical method was used to detect the expression of CDKN3 in 12 ca-ses of HPV16-positive cervical cancer,12 cases of HPV16-positive cervical precancerous lesions,10 cases of HPV16-positive chronic cervicitis and 7 cases of HPV-negative normal cervical samples collected from the Af-filiated Hospital of Guizhou Medical University.SiHa(HPV16-positive),HeLa(HPV18-positive)and HCC94(HPV-negative)cervical cancer cell lines were selected,and their CDKN3 expression were detected by West-ern blot.Results The GEPIA platform analysis showed that CDKN3 was highly expressed in pan-cancer,and the expression level of CDKN3 in cervical cancer tissue was significantly higher than that in normal cervical tissue(P<0.05).The GEO dataset reflected a significantly increased CDKN3 mRNA expression level in HPV16-positive cervical cancer compared to normal cervical tissue(P<0.001).Immunohistochemical verifi-cation showed that the positive expression rates of CDKN3 in HPV16-positive cervical cancer,HPV16-positive cervical precancerous lesion,HPV16-positive chronic cervicitis and HPV-negative normal cervical tissues were 91.7%,58.3%,0 and 0,respectively.Western blot analysis of cervical cancer cells showed that the expression level of CDKN3 in SiHa(HPV16-positive)cells was significantly higher than that in HeLa(HPV18-positive)and HCC94(HPV-negative)cells(P<0.05).Conclusion CDKN3 is a new oncogene of HPV16-positive cer-vical cancer,which may be used as a marker of cervical precancerous lesions and cervical cancer screening,and may provide a theoretical basis for subsequent mechanism research and targeted therapy.

Application of gelatin methacryloyl as a three-dimensional cell culture scaffold in bone tissue engineering / 中国组织工程研究

BACKGROUND:The treatment of bone defects has always been a pressing clinical challenge for medical practitioners.The use of gelatin methacryloyl for three-dimensional extracellular cultivation offers a promising direction for the treatment of extensive bone defects. OBJECTIVE:To review the research progress of gelatin methacryloyl as a three-dimensional cell culture scaffold in bone tissue engineering,aiming to provide further references for clinical bone defect repair. METHODS:Computerized searches were conducted on the CNKI and PubMed databases for articles published from January 1986 to August 2023.The search terms in Chinese and English were"bone defect,bone tissue engineering,biomaterial scaffold,hydrogel,photocrosslinked hydrogel,gelatin methacryloyl,three-dimensional culture,cell culture"and"bone defect,bone tissue engineering,biomaterial scaffold,hydrogel,gelatin methacryloyl,three-dimensional culture,cell culture",respectively.Finally,68 articles were included for review and analysis. RESULTS AND CONCLUSION:(1)When compared to two-dimensional culture techniques,three-dimensional culture can construct a three-dimensional space under aseptic conditions,more effectively simulating the in vivo environment.It provides cells with the appropriate temperature,pH,and sufficient nutrients,allowing cells to grow and proliferate normally outside the body while maintaining their regular structure and function,offering unique advantages.(2)In the realm of bone tissue engineering,hydrogels stand out as the preferred choice for biomaterial scaffolds.Their excellent biocompatibility,degradability,and inherent three-dimensional network structure make them invaluable in bone regeneration studies.(3)The physical and biological properties of gelatin methacryloyl are influenced by factors such as concentration,light exposure duration,type of photoinitiator,and the overall reaction system.These properties can affect cell adhesion,growth,and proliferation,and even the morphology and function of cells.(4)Gelatin methacryloyl,recognized for its excellent biocompatibility,tunable physical properties,injectability,and photosensitivity,has been extensively used in three-dimensional cell encapsulation,three-dimensional bioprinting,and stereolithography techniques based on digital light processing in three-dimensional cell culture systems.(5)Utilizing a range of composite gelatin methacryloyl in three-dimensional cell culture can significantly promote vascularization and bone regeneration,paving the way for enhanced clinical solutions to bone defects.(6)At present,there is a noticeable gap in standardized guidelines concerning the sources,synthesis methods,and safety of gelatin methacryloyl.It is crucial to intensify research efforts to optimize gelatin methacryloyl's application in the three-dimensional cell culture field.

Discussion on Management Experience of Public Cell Culture Platform in Laboratory Animal Center of Shanghai Jiao Tong University / 实验动物与比较医学

Public cell culture platform is an important facility in laboratory animal facilities, providing essential support for scientific research such as the development of animal tumor disease models and transgenic animals. By establishing a public cell culture experimental platform, laboratory animal centers can effectively integrate experimental animals and cell culture resources, optimizing the allocation of scientific research resources to facilitate better research outcomes. The majority of cells cultured in these platforms are used for animal experiments. Contamination or quality issues in these cells not only affect experimental results but also jeopardize the health of experimental animals, potentially leading to microbial infections and contamination of entire animal facilities. Therefore, public cell culture laboratories within experimental animal facilities impose stricter quality control measures than conventional cell culture rooms. This study takes the public cell culture platform at the Laboratory Animal Center of Shanghai Jiao Tong University as a case study to discuss management experiences, focusing on facility maintenance and management, personnel management and quality control of cell biological risk. The aim is to provide useful reference for the management of public cell culture laboratories in experimental animal facilities and other institutions.

Research advances in liver cancer organoids / 临床肝胆病杂志

Organoids are a novel disease model that is self-assembled from stem cells or malignant tumors and is used in clinical research. They are similar to tissues and organs in the body and have partially functional 3D cell structures. There are two types of traditional models for liver cancer research， i.e.， in vivo models （animal models of liver cancer established by induction） and in vitro cell experiments using corresponding cell lines. Organoids have the advantages of the two types of traditional models and show unique advantages in tumor research. Traditional models cannot fully reflect the microenvironment of cells， which often leads to the inconsistency with clinical research findings， and the emergence of new research models provides a new direction for the research on liver cancer. This article reviews the research advances in liver cancer organoids， in order to provide a new perspective for future research on liver cancer.

Development and verification of multiplex fluorescent quantitative PCR for detection of bacteria and fungi in cell culture medium / 中国生物制品学杂志

@#Objective To develop and verify a multiplex fluorescent quantitative PCR method for detection of common bacterial and fungal contaminants in cell culture medium.Methods According to NUC gene of Staphylococcus aureus,COLA gene of Clostridium spore,ITS-2 segment sequence of Candida albicans,a set of primers and probes were designed for each respectively,and using UBI3 gene of capsicum introduced as external standard gene,a triple reaction system of Staphylococcus aureus,Clostridium spore and external standard gene and a double reaction system of Candida albicans and external standard gene were established.The primer specificity,linear range,limit of detection,specificity,anti-interference performance and precision of the method were verified.Finally,100 samples of 293T cell culture medium were detected by using the developed method,which was compared with the common PCR method.Results Three pairs of primers all amplified about 100 bp specific gene bands corresponding to the three strains at different annealing temperatures(56,57,58 and59 ℃),and the size was consistent with the expected.In the range of 5.80 × 10~6 — 5.80 × 10~2 copies/μL,the standard plasmids of the three strains showed a good linear relationship with the Ct values.The standard curve equations were:Y=-3.373 X+37.48,Y=-3.557X+36.59 and Y=-3.536 X+39.78,each R~2> 0.99,respectively,and the amplification efficiency was in the range of 90%—110%.All the limits of detection of the three strains were 10~1 CFU/mL.The primers and probes of the three strains showed no specific amplification on the genomic DNA of six kinds of cells that were prone to cross-reaction.The genomic DNA of 293T cells,Yeast,Escherichia coli and Mycoplasma sp.had no effect on the detection.The CVs of repeatability and intermediate precision verification were both less than 15%.Among 100 cell culture medium samples,14 positive and 86 negative samples were detected,and the results of common PCR method for three positive and two negative samples randomly selected were consistent with the developed method.Conclusion The multiplex fluorescent quantitative PCR method developed in this study for the detection of bacteria and fungi in cell culture medium has good specificity,anti-interference performance and precision,and is simple to operate with low cost and high sensitivity,which can quickly detect the contaminants during cell culture.

Culture of rabbit corneal stromal cells on thermo-sensitive materials by the radiation polymerization / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To explore the synthesis of thermo-sensitive poly N-isopropylacry-lamide(PNIPAAm)and the petri dish grafted with PNIPAAm hydrogels by the electron accelerator, as well as the growth conditions and the biological characteristics of rabbit corneal stromal cells on thermo-sensitive PNIPAAm hydrogels, and the cell sheets obtained from the PNIPAAm hydrogels.METHODS: NIPAAm monomer was dissolved in 2-propanol at concentrations of 55% with 0.5% N,N'-Methylenebisacry-lamide(MBA). Solution(70 μL)was added and spread uniformly over 35 mm petri dish. These dishes were immediately subjected to irradiation. After follow-up treatment, rabbit corneal stromal cells were cultured on thermo-sensitive petri dish in vitro.RESULTS: According to the monomer formula and radiation synthesis scheme in this experiment, PNIPAAm can be synthesized on the surface of the petri dish. Rabbit corneal stromal cells grew well in the thermo- sensitive surface and can be separated into sheets.CONCLUSION: The single and multilayer carrier-free cell sheets can be obtained from the use of thermo-sensitive petri dish.

Construction strategies of skin organoids: a review / 中华创伤杂志

Large skin defect caused by severe trauma is a common clinical problem with high incidence, great harm, difficult treatment and poor prognosis, which not only seriously affects the quality of patients′ life, but also threatens their lives. Large skin defects are difficult to heal by themselves and the main treatment is skin transplantation. However, the source of the autologous flap is limited and may cause secondary damage to patients. The artificial skin has poor mechanical integrity that cannot be integrated, causing formation of scars, and also has the risk of immune rejection. Skin organoid technology can extremely simulate the human skin tissue and its functions. Thus, it can overcome the shortcomings of the current skin wound treatment to a certain extent and provide a new treatment for the patients with large skin defects. At present, the construction methods of skin organoids are relatively mature, but each method has its advantages and disadvantages, and the best method has not been determined yet. Moreover, the structure and function of skin organoids are relatively simple, so there is still a relatively big gap between skin organoids and real human skin. Hence, the authors reviewed the research progress in skin organoid construction strategies from organoids′ skin organoid technology, and construction methods of skin organoids, hoping to provide a reference for the construction of skin organoids with more complex structures and functions in the future.

Characteristic analysis of fibracel carriers for animal cell culture / 中国生物制品学杂志

@#Objective To investigate the surface properties of different fibracel carriers and their culture effects on different cells.Methods Three fibracel carriers(A,B,C)were selected to analyze the chemical element composition of their materials,and the contact angles of the carriers before and after pretreatment with 0. 1 mol/L NaOH solution were tested. By measuring the adhesion effect and glucose consumption of Vero,MDCK and MRC-5 cells on the carrier,and observing the cell growth state by fluorescent staining,the cell adhesion efficiency and culture effect of the three carriers were compared and analyzed.Results The three carriers were mainly composed of C,H,O,and contained a small amount of N and S elements. Before pretreatment,the contact angle of carrier B was 0°,which was significantly lower than that of A[(109 ± 3. 13)°]and C[(121 ± 6. 82)°]（each F = 709. 1,each P < 0. 000 1）,and the hydrophilicity was stronger. Carriers A and C had poor hydrophilicity. After pretreatment,the contact angles of the surfaces of the three carriers A,B,and C were all 0°,with no significant difference(F = 0. 069 4,P > 0. 05),all of which were hydrophilic. The adherence rates of the three types of carriers within 3 h of cell culture were all above 80%. The cells were dense and evenly grown on the carrier fibers,the glucose consumption curves tended to“S”type,and the continuous cell culture effect was good. The total glucose consumption of carrier A and carrier C was basically the same,and carrier B was lower than carrier A and carrier C.Conclusion The chemical element composition and the relationship between the hydrophilic and hydrophobic properties of the three fibracel carriers were analyzed,and the adhesion rate and culture effect of Vero,MDCK and MRC-5 cells were evaluated,which provide reference for the subsequent research and production application of fibracel carriers.

Comparison of techniques for corneal epithelium cell culture for the collection of conditioned medium / Comparação das técnicas de cultivo de células epiteliais da córnea para a coleta de meio condicionado

ABSTRACT Purposes: To determine the best protocol in obtaining the higher yield of conditioned culture medium to be used for the bone marrow mesenchymal stem cell differentiation into corneal epithelial cells, five techniques for the primary culture of human corneal epithelial cells were evaluated. Methods: The studied culture techniques of corneal epithelial cells were: explants in culture flasks with and without hydrophilic surface treatment, on amniotic membrane, with enzymatic digestion, and by corneal scraping. The conditioned culture medium collected from these cultures was used to differentiate human bone marrow mesenchymal stem cells into corneal epithelial cells, which were characterized using flow cytometry with pan-cytokeratin and the corneal-specific markers, cytokeratin 3 and cytokeratin 12. Results: The culture technique using flasks with hydrophilic surface treatment resulted in the highest yield of conditioned culture medium. Flasks without surface treatment resulted to a very low success rate. Enzymatic digestion and corneal scraping showed contamination with corneal fibroblasts. The culture on amniotic membranes only allowed the collection of culture medium during the 1st cell confluence. The effectiveness of cell differentiation was confirmed by cytometry analysis using the collected conditioned culture medium, as demonstrated by the expressions of cytokeratin 3 (95.3%), cytokeratin 12 (93.4%), and pan-cytokeratin (95.3%). Conclusion: The culture of corneal epithelial cell explants in flasks with hydrophilic surface treatment is the best technique for collecting a higher yield of conditioned culture medium to be used to differentiate mesenchymal stem cells.

RESUMO Objetivos: Foram estudadas cinco técnicas de cultivo primário de células epiteliais de córnea humana para se determinar o melhor protocolo para a obtenção do maior rendimento de meio de cultivo condicionado para ser utilizado na diferenciação de células tronco mesenquimais para células epiteliais de córnea. Métodos: As técnicas de cultivo estudadas foram: explantes em frascos de cultivo com e sem tratamento hidrofílico de superfície, sobre membrana amniótica, com digestão enzimática e por raspado de córnea. O meio de cultivo condicionado foi coletado e as células tronco mesenquimais induzidas a se diferenciarem em células epiteliais da córnea utilizando o meio de cultivo condicionado. As células foram caracterizadas por citometria de fluxo com pan-citoqueratina e com os marcadores específicos da córnea, citoqueratina 3 e citoqueratina 12. Resultados: A técnica utilizando frascos com o tratamento de superfície apresentou o maior rendimento de meio de cultivo condicionado. Os frascos sem tratamento de superfície levaram a uma taxa de sucesso muito baixa. A digestão enzimática e a raspagem da córnea mostraram contaminação das culturas com fibroblastos de córnea. A cultura sobre membranas amnióticas só permitiu a coleta do meio de cultivo condicionado durante a 1ª confluência celular. A análise de citometria de fluxo confirmou o sucesso da diferenciação celular utilizando o meio de cultivo condicionado coletado, demonstrada pela expressão de citoqueratina 3 (95,3%), citoqueratina 12 (93,4%) e pan-citoqueratina (95,3%). Conclusão: O cultivo de explantes de células tronco mesenquimais em frascos com tratamento hidrofílico de superfície é a melhor técnica para a obtenção de um alto rendimento de meio de cultivo condicionado.

SARS-CoV-2 shedding, infectivity, and evolution in an immunocompromised adult patient

ABSTRACT This study aimed to provide further insight into the evolutionary dynamics of SARS-CoV-2 by analyzing the case of a 40-year-old man who had previously undergone autologous hematopoietic stem cell transplantation due to a diffuse large B-cell lymphoma. He developed a persistent SARS-CoV-2 infection lasting at least 218 days and did not manifest a humoral immune response to the virus during this follow-up period. Whole-genome sequencing and viral cultures confirmed a persistent infection with a replication-positive virus that had undergone genetic variation for at least 196 days after symptom onset.

Effects of rosmarinic acid and doxorubicine on an ovarian adenocarsinoma cell line (OVCAR3) via the EGFR pathway

Purpose: We aimed to reveal the effects of rosmarinic acid (RA), which has come to the forefront with its antitumor and antioxidant properties in many studies recently in the ovarian adenocarcinoma cell line, on the epidermal growth factor receptor (EFGR) signaling pathway in the presence of doxorubicin (DOX). Methods: Ovarian adenocarcinoma cell line (OVCAR3) and human skin keratinocyte cell line human skin keratinocyte cell line (HaCaT) were used as control. (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was applied to determine the effect of RA and DOX on the proliferation of OVCAR3 and HaCaT cells. Bcl2 expression and epidermal growth factor receptor (EGFR) and western blot analysis were performed to determine the expression levels of the markers. Results: It was determined that RA (IC50 = 437.6 µM) and DOX (IC50 = 0.08 µM) have the ability to inhibit the proliferation of OVCAR3 cells and induce apoptosis in a 72-hour time and dose-dependent manner. Western blot showed that the expression level of Bcl-2 and EGFR in OVCAR3 cells was down-regulated by RA and DOX. Conclusions: Apoptosis in OVCAR3 cells can potentially be induced by RA via the EGFR pathway, and RA may be a potent agent for cancer therapy.

Adult human neural cells in culture following traumatic brain injury

Objective: The present study aims to evaluate the viability of adult human neural cells in culture obtained from traumatized brain tissues collected in emergency surgery procedures. Methods: Exploratory, descriptive, quantitative and cross-sectional study evaluating samples obtained from patients who underwent traumatic brain injury with extrusion of brain tissue submitted to cell culture in a standardized medium, being preserved during 168h. After observation under phase contrast microscopy and immunohistochemical processing for neuronal (MAP-2) and glial (GFAP) markers, morphometric parameters of neural cells (cell body area, dendritic field length and fractal dimension) were evaluated using ImageJ software, with data obtained after 24, 72 and 168h being compared using non-parametric Kruskal Wallis test, followed by Dunn's post hoc test. Results: The explant of the nervous tissue revealed a consolidated pattern of cell migration into the culture medium. Cell proliferation, upon reaching confluence, presented an aspect of cellular distribution juxtaposed along the culture medium at all time points analyzed. Both neurons and glial cells remained viable after 168h in culture, with their morphologies not varying significantly throughout the time points evaluated. Immunohistochemistry for MAP-2 showed a relatively well-preserved cytoskeletal organization. GFAP immunoreactivity revealed activated astrocytes especially at the later time point. Conclusions: Our results point out the viability of cell culture from traumatized human nervous tissue, opening up perspectives for the use of substances of natural origin that may contribute neuroprotectively to neuronal maintenance in culture, allowing future translational approach.

Desarrollo y validación de un método de suspensión basado en células Vero para la detección del virus Zika / Development and validation of a vero cell-based suspension method for the detection of Zika virus

Objetivo . Desarrollar y validar un método de suspensión celular utilizando células Vero 76 para el cultivo del virus Zika (ZIKV) basado en la infección de células recién sembradas no adheridas. Material y métodos . Se utilizaron tres multiplicidades de infección diferentes del ZIKV para desarrollar y comparar este novedoso método con el método estándar de monocapa de células confluentes. Además, validamos preliminarmente el método de suspensión utilizando muestras clínicas caracterizadas como positivas o negativas para el ZIKV. El método estándar de monocapa se utilizó como método de referencia, y el aislamiento viral se confirmó mediante un RT-PCR específico del ZIKV. Se estimó la sensibilidad e intervalos de confianza del 95% para el método de suspensión. Asimismo, se realizó una comparación técnica del método de suspensión contra el método de monocapa. Resultados . Nuestros hallazgos sugieren que tanto la carga viral como la replicación del ZIKV fueron comparables entre los métodos de infección en monocapa y en suspensión. Aunque ambos métodos fueron adecuados para cultivar y aislar el ZIKV, el método de suspensión se caracterizó por ser más fácil, barato y rápido, así como una técnica de aislamiento sensible. En comparación con el método de monocapa, el método de suspensión fue cuatro veces más sensible en la detección del ZIKV en casos inconclusos por RT-PCR. Conclusiones . El método de suspensión tiene el potencial de ser un método eficaz para cultivar y aislar el ZIKV y su uso es potencialmente útil tanto en la investigación como en entornos clínicos.

Objective. To develop and validate a cell suspension method using Vero 76 cells for culturing Zika virus (ZIKV) based on infection of detached freshly seeded cells. Material and methods. Three different multiplicities of infection of ZIKV were used to develop and compare this novel method to the standard confluent cell monolayer method. In addition, we preliminary validated the cell suspension method using well-characterized ZIKV positive and negative clinical samples. The standard confluent cell monolayer method was used as the reference method, and viral isolation was confirmed by a ZIKV-specific RT-PCR. The sensitivity and its 95% confidence intervals for the cell suspension method were estimated. Also, a technical comparison of the cell suspension method against the cell monolayer method was performed. Results. Our findings suggested that both the viral load and replication of ZIKV were comparable between both monolayer- and suspension-infection methods. Although both methods were suitable for culturing and isolating ZIKV, the cell suspension method was easier, cheaper, and quicker as well as a sensitive isolation technique. The cell suspension method was significantly more sensitive in detecting Zika in inconclusive cases by RT-PCR, with a fourfold increase compared to the confluent cell monolayer method. Conclusion. The cell suspension method has the potential to be an effective method for cultivating and isolating ZIKV and its application is potentially useful in both research and clinical settings.

Isolation and identification of primary brain microvascular endothelial cells of rat using thin-layer cell culture method / 神经解剖学杂志

Objective:To extract rat brain microvascular endothelial cells(BMECs)using thin-layer cell culture method.Methods:The brain cortex of four-week-old SD rats was obtained,which was chopped,sieved,and digested with type II collagenase to obtain microvascular segments.The amount of culture medium was strictly controlled,and it was inoculated into culture flasks for primary culture.The target cells were morphologically observed by using an invert-ed phase contrast microscope,and the factor Ⅷ related antigen(FⅧRag)was identified by using immunocytochemi-cal staining.Results:The target cells cultured in the inverted phase contrast microscope showed typical endothelial-like monolayer cobble stone-like mosaic growth;FⅧRag positive cells accounted for more than 99％of the total cells.Conclusion:Thin-layer cell culture method can successfully isolate and cultivate high-purity rat BMECs.

Types and control methods of black dot⁃like contaminants in cell cultures / 安徽医科大学学报

Objective @#To explore the type and control measure of black dot⁃like contaminants in cell cultures.@*Methods@#The growth state of bacteria was investigated under an inverted microscope ; Their morphological characteristics were analyzed by Gram and auramine O staining as well as electron microscopy; 16S rDNA gene sequencing was used to analyze bacterial species ; Drug sensitivity test was used to screen antibiotics against the bacteria;Cryopreserved SH⁃SY5Y cells were resuscitated by cell culture supernatant of RAW264 cells.@*Results@#Inverted microscopic real⁃time observations showed that black dot⁃like substances had two growth states : static and moving.They were negative for Gram staining while positive for auramine O staining. Electron microscopy revealed that they were short rod⁃shaped bacteria with a polar flagellum during moving phase. 16S rDNA gene sequencing showed that these bacteria were phenylobacterium zucineum HLK1. Ceftriaxone , carboxycillin and imipenem were screened by drug sensitivity test to have inhibitory effects on the bacteria , but cell culture experiments showed that they could not remove the bacteria from SH⁃SY5Y cells. Contaminated cells could not be cryopreserved for a long time , but resuscitation with RAW264. 7 cell culture supernatant significantly improved the survival rate of cells.@*Conclusion@#The black dot⁃like contaminants in cell cultures are a special type of oligotrophic bacterium with strong viability that can invade the cells and cannot be cleared with antibiotic treatment. RAW264. 7 cell culture supernatant seems contain some substances against bacteria , and resuscitating frozen cells with RAW264. 7 cell culture supernatant may significantly improve the survival rate of cells.

Opportunities,challenges and suggestions for development of cell culture media industry in China / 中国生物制品学杂志

@#Cell culture medium is one of the essential raw materials in the field of life and health.In recent years,the performance and quality of domestic cell culture media have been improving,and the market share of domestic vendors has steadily increased from 19.2% in 2017 to 33.7% in 2021.However,there are also some problems and shortcomings in industrial development,mainly including:technology and process accumulation need to be strengthened;product quality need to be improved;lack of industry standards and norms.Based on literature research,special topic discussion and expert interview,this paper reviews the development history of cell culture medium,deeply analyzes and systematically combs the opportunities and challenges faced by the industry development from the basic situation,current situation and trend of the development of cell culture medium industry in China,and puts forward relevant countermeasures and suggestions.

Progress on three-dimensional cell culture technology and their application / 生物医学工程学杂志

Three-dimensional (3D) cell culture model is a system that co-culture carriers with 3D structural materials and different types of cells in vitro to simulate the microenvironment in vivo. This novel cell culture model has been proved to be close to the natural system in vivo. In the process of cell attachment, migration, mitosis and apoptosis, it could produce biological reactions different from that of monolayer cell culture. Therefore, it can be used as an ideal model to evaluate the dynamic pharmacological effects of active substances and the metastasis process of cancer cells. This paper compared and analyzed the different characteristics of cell growth and development under two-dimensional (2D) and 3D model culture and introduced the establishment method of 3D cell model. The application progress of 3D cell culture technology in tumor model and intestinal absorption model was summarized. Finally, the application prospect of 3D cell model in the evaluation and screening of active substance was revealed. This review is expected to provide reference for the development and application of new 3D cell culture models.

Chronic exposure to lipopolysaccharides as an in vitro model to simulate the impaired odontogenic potential of dental pulp cells under pulpitis conditions

Abstract Simulating a bacterial-induced pulpitis environment in vitro may contribute to exploring mechanisms and bioactive molecules to counteract these adverse effects. Objective To investigate the chronic exposure of human dental pulp cells (HDPCs) to lipopolysaccharides (LPS) aiming to establish a cell culture protocol to simulate the impaired odontogenic potential under pulpitis conditions. Methodology HDPCs were isolated from four healthy molars of different donors and seeded in culture plates in a growth medium. After 24 h, the medium was changed to an odontogenic differentiation medium (DM) supplemented or not with E. coli LPS (0 - control, 0.1, 1, or 10 µg/mL) (n=8). The medium was renewed every two days for up to seven days, then replaced with LPS-free DM for up to 21 days. The activation of NF-κB and F-actin expression were assessed (immunofluorescence) after one and seven days. On day 7, cells were evaluated for both the gene expression (RT-qPCR) of odontogenic markers (COL1A1, ALPL, DSPP, and DMP1) and cytokines (TNF, IL1B, IL8, and IL6) and the production of reactive nitrogen (Griess) and oxygen species (Carboxy-H2DCFDA). Cell viability (alamarBlue) was evaluated weekly, and mineralization was assessed (Alizarin Red) at 14 and 21 days. Data were analyzed with ANOVA and post-hoc tests (α=5%). Results After one and seven days of exposure to LPS, NF-κB was activated in a dose-dependent fashion. LPS at 1 and 10 µg/mL concentrations down-regulated the gene expression of odontogenic markers and up-regulated cytokines. LPS at 10 µg/mL increased both the production of reactive nitrogen and oxygen species. LPS decreased cell viability seven days after the end of exposure. LPS at 1 and 10 µg/mL decreased hDPCs mineralization in a dose-dependent fashion. Conclusion The exposure to 10 µg/mL LPS for seven days creates an inflammatory environment that is able to impair by more than half the odontogenic potential of HDPCs in vitro, simulating a pulpitis-like condition.