Bone Marrow Cells ; Cell Line ; Cell Proliferation ; Humans ; Mesenchymal Stromal Cells ; cytology ; T-Lymphocytes ; cytology ; T-Lymphocytes, Regulatory ; cytology

To evaluate the separation of T lymphocyte subsets by immunomagnetic beads and to find optimization of strategy for specific binding of antibody-coated beads to cells, two strategies to isolate enriched T lymphocyte subpopulation CD4+ T cells and CD8+ T cells from small volumes (< 5 ml) of peripheral blood by using immunomagnetic beads or complement cytotoxicity method were compared. The purity and activity of CD4+ T cells and CD8+ T cells were measured by using flow cytometry, trypan-blue dye exclusion test, etc. The results showed that the yields of CD4+ T lymphocytes and CD8+ T lymphocytes by using immunomagnetic beads were (94.2 +/- 1.4)% and (93.8 +/- 3.0)% respectively, higher than those of control group and the group of using completement cytotoxicity method (P < 0.05). At the same time, the yields of CD4+ T lymphocytes and CD8+ T lymphocytes by using complement cytotoxicity method were (76.0 +/- 2.8)% and (77.0 +/- 3.0)% respectively, higher than those of unenriched group (P < 0.05). The trypan-blue dye exclusion test confirmed that there were no influences on activity of CD4+ T cells and CD8+ T cells when immunomagnetic beads were used for separation of these cells from peripheral blood. It is concluded that the immunomagnetic bead method has a higher efficiency for separation of CD4+ T cells and CD8+ T cells from peripheral blood than complement cytotoxic method, especially for small sample. This method has no influence on activity and proliferation of T lymphocyte subpopulations, and would be expected to establish conditions for research of biological characteristics of CD4+ T cells and CD8+ T cells in future.
CD4-Positive T-Lymphocytes ; cytology ; CD8-Positive T-Lymphocytes ; cytology ; Flow Cytometry ; Humans ; Immunomagnetic Separation ; methods ; Leukocytes, Mononuclear ; cytology ; immunology

BACKGROUND: The usefulness of the CytoDiff flow cytometric system (Beckman Coulter, USA) has been studied in various conditions, but its performance including rapidity in detecting and counting blasts, the most significant abnormal cells in the peripheral blood, has not been well evaluated. The objective of this study was to evaluate the performance of the CytoDiff differential counting method in challenging samples with blasts. METHODS: In total, 815 blood samples were analyzed. Samples flagged as "blasts" or "variant lymphocytes" and showing <10% blasts by manual counts were included. In total, 322 samples showed blasts on manual counts, ranging from 0.5% to 99%. The CytoDiff method was performed by flow cytometry (FC500; Beckman Coulter, USA) with a pre-mixed CytoDiff reagent and analyzing software (CytoDiff CXP 2.0; Beckman Coulter). RESULTS: The average time required to analyze 20 samples was approximately 60 min for manual counts, and the hands-on time for the CytoDiff method was 15 min. The correlation between the CytoDiff and manual counts was good (r>0.8) for neutrophils and lymphocytes but poor (r<0.8) for other cells. When the cutoff value of the CytoDiff blast count was set at 1%, the sensitivity was 94.4% (95% CI; 91.2-96.6) and specificity was 91.9% (95% CI; 89.0-94.1). The positive predictive value was 88.4% (95% CI; 84.4-91.5) (304/344 cases) and negative predictive value was 96.2% (95% CI; 93.9-97.7) (453/471 cases). The CytoDiff blast counts correlated well to the manual counts (r=0.9223). CONCLUSIONS: The CytoDiff method is a specific, sensitive, and rapid method for counting blasts. A cutoff value of 1% of at least 1 type of blast is recommended for positive CytoDiff blast counts.
Adult ; Female ; Flow Cytometry/*instrumentation ; Humans ; Leukocyte Count ; Leukocytes/*cytology ; Lymphocytes/cytology ; Male ; Neutrophils/cytology

The anatomical location of lymphocyte ontogeny in the developing mouse embryo remains controversial. To define the site that can generate lymphocytes de novo, the intraembryonic splanchnopleura (SP) and extraembryonic yolk sac (YS) at 8.5 days postcoitum, when systemic circulation is not established, were investigated. The results indicated that in standard colony forming assay, the cells from both splanchnopleura and yolk sac formed typical myeloerythroid colonies, but their types were distinct. When cocultured with the OP9, the splanchnopleura produced B cells expressing B220, CD19 and surface IgM. Using a three-step culture protocols with the OP9 expressing Delta-like 1 as feeders, the splanchnopleura produced immature T precursor cells (CD44-/CD25+) and more mature single positive T cells (CD4+/CD8-) after 16 days of incubation. However, the yolk sac failed to generate B and T lymphocytes under identical conditions. It is concluded that prior to linked embryonic circulation, the splanchnopleura other than the yolk sac had robust lymphoid potential in vitro. In the future, more reliable evidence from novel model animals will ultimately delineate the embryonic origin of lymphocytes in vivo.
Animals ; B-Lymphocytes ; cytology ; Cell Differentiation ; Coculture Techniques ; Female ; Hematopoietic Stem Cells ; cytology ; Mice ; Mice, Inbred C57BL ; Pregnancy ; T-Lymphocytes ; cytology ; Yolk Sac ; cytology

There has been a history of 30 years in the study of CD4(+)CD25(+) T regulatory cells (Treg) which primarily play a role of immune suppression in vivo. Many autoimmune diseases are related to the decrease and the disorder of these cells, such as multiple sclerosis, non-obese diabet (NOD) and lupus erythematosus. In the field of transplantation tolerance, the role played by Treg is also very important. All of these features have drawn the attention to the prevention of autoimmune diseases and the rejection of transplantation. However, the low frequency of Treg in vivo affected their use and study. Currently, many techniques about expansion of Treg in vitro have been established so as to overcome the problem of their limited cell numbers in vivo. Recent studies suggest that antigen-specific T regulator cells (sTreg) expanded by dentritic cells (DC) showed a superior immunosuppression in comparison with polyclonal Treg expanded by anti-CD3/CD28Ab, which is the focus of current studies. This article mainly reviews and compares the expansion techniques and the mechanism of regulatory T cells.
Cell Culture Techniques ; Humans ; Immunosuppression ; T-Lymphocytes, Regulatory ; cytology ; immunology

BACKGROUND: We investigated the characteristics of the mononuclear cells remaining in the leukoreduction system (LRS) chambers of Trima Accel(R) in comparison with those of standard buffy coat cells, and evaluated their potential for differentiation into dendritic cells. METHODS: Twenty-six LRS chambers of Trima Accel(R) were collected after platelet pheresis from healthy adults. Flow cytometric analysis for T, B, NK, and CD14+ cells was performed and the number of CD34+ cells was counted. Differentiation and maturation into dendritic cells were induced using CD14+ cells seperated via Magnetic cell sorting (MACS(R)) Seperation (Miltenyi Biotec Inc., USA). RESULTS: Total white blood cell (WBC) count in LRS chambers was 10.8x108 (range 7.7-18.0x108). The median values (range) of proportions of each cells were CD4+ T cell 29.6% (18.7-37.6), CD8+ T cell 27.7% (19.2-40.0), B cell 5.5% (2.2-12.1), NK cell 15.7% (13.7-19.9), and CD14+ cells 12.4% (8.6-32.3) respectively. Although total WBC count was significantly higher in the buffy coat (whole blood of 400 mL) than the LRS chambers, the numbers of lymphocytes and monocytes were not statistically different. The numbers of B cells and CD4+ cells were significantly higher in the buffy coat than the LRS chambers (P<0.05). The median value (range) of CD34+ cells obtained from the LRS chambers was 0.9x10(6) (0.2-2.6x10(6)). After 7 days of cytokine-supplemented culture, the CD14+ cells were successfully differentiated into dendritic cells. CONCLUSIONS: The mononuclear cells in LRS chambers of Trima Accel(R) are an excellent alternative source of viable and functional human blood cells, which can be used for research purposes.
Adult ; B-Lymphocytes/cytology/immunology ; CD4-Positive T-Lymphocytes/cytology/immunology ; CD8-Positive T-Lymphocytes/cytology/immunology ; Cell Differentiation ; Dendritic Cells/*cytology/immunology ; Flow Cytometry ; Humans ; Killer Cells, Natural/cytology/immunology ; Plateletpheresis/*instrumentation

In order to study the influence of different gelatin concentrations, and lymphocyte isolation liquid on primary culture of umbilical cord blood-derived adhesive cells (hCBACs), the red blood cells of umbilical cord blood was separated by 3% and 6 % gelatin for detecting the effectiveness of sedimentation, then the adhesion rate at 48 hours, the day of initial expansion and the rate of culture success were detected for hCBACs cultured with CD34(+) cells after the mononuclear cells were separated by 6% gelatin followed by Ficoll and Percoll, and the morphological characteristics and growth status were observed by invert microscopy. Cytochemistry stain for nonspecific esterase stain (NSE), peroxidase (POX), periodic acid Schiff reaction (PAS) and alkali phosphatase (ALP) and immunocytochemistry labeling for CD31, CD45, CD68 and fibronectin (Fn) were detected. The results showed that 6 % gelatin was better than that 3% gelatin for red blood sedimentation. The Percoll was predominant over Ficoll in adhesion rate at 48 hours, the day of initial expansion, the time of initial formation of adhesive cell colony units, the time of maximal numbers of adhesive cell colony units, the the cell fusion time and ratio of culture success. 60% fibroblast-liked cells, 36% macrophage liked cells and 4% small-round cells were observed in cells isolated by both isolated methods. The cytochemistry stain for NSE, POX, PAS and ALP was similar in two groups, the difference was not statistically significant between these two groups. The immunocytochemistry labeling for CD31, CD45, CD68 and Fn was also similar in both groups and the difference was also not statistically significant between these two groups. It is concluded that the combination of 6% gelatin with Percoll is an ideal separation method for primary culture of hCBACs, which provides basic information for clinical application.
Cell Separation ; methods ; Cells, Cultured ; Fetal Blood ; cytology ; Gelatin ; administration & dosage ; pharmacology ; Humans ; Lymphocytes ; cytology

OBJECTIVE: To study cellular immune function of palatine tonsil B lymph cell. METHOD: The phenotype of palatine tonsil cells (PTC) and that of peripheral blood mononuclear cell (PBMC) were compared using fluorescence staining and flow cytometry (FCM) analysis, then immunomagnetic beads were used to separate CD3- cell in PTC and PBMC. The proliferation function of CD3- lymph cell of PTC and PBMC was tested after stimulated by CD20mAb. RESULT: FCM analysis founding that 71.2% PTC express CD20 with higher mean fluorescence intensity, MFI, compared to the 15.5% in PBMC. There's no significant difference between the proliferation of PTC and PBMC B lymph cell. CONCLUSION CD20 expression is different in PTC and PBMC, but corresponding function is still unknown.
Adult ; Antigens, CD20 ; metabolism ; B-Lymphocytes ; cytology ; immunology ; metabolism ; Flow Cytometry ; Humans ; Palatine Tonsil ; cytology ; immunology

OBJECTIVETo compare the biological characteristics and immunosuppressive activity between human amniotic mesenchymal stem cells (hAMSC) and human bone marrow mesenchymal stem cells (hBMMSC).

METHODSMSC from human amnion and bone marrow were isolated using enzymatic digestion and Ficoll-Hypaque density gradients, respectively. Their biological characteristics were compared by morphology, cell growth curves, cell cycle profile analysis, immunophenotype and immunofluorescence assay. Their immunosuppressive activities were studied on total activated T-cells with phytohemagglutinin (PHA-PBMSC). An in vitro co-culture was performed to compared the lymphocyte proliferation and the supernatant level of IFN-γ were measured by CCK-8 method and ELISA, respectively.

RESULTSBoth hAMSC and hBMMSC demonstrated fibroblast-like morphology. The hAMSC were able to be amplified for at least 15 passages, while the hBMMSC only for 6-7 passages. There was no significant difference in the proportion of G2/M phase cells of the 2 cells types (P>0.05). By FACS analysis for immunophenotype, both MSC were shown to be positive for CD105, CD90, CD73 and negative for CD34, CD45, CD11b, CD19, HLA-DR, but hAMSC were positive for Oct-3/4, which was in contrast to hBMMSC. Both of them expressed vimentin. Both the cells exhibited a inhibitory role on the lymphocyte proliferation induced by PHA in co-culture conditions, that was increased with the increase MSC proportion and both the suppressing effecs were enhanced. The supernatant IFN-γ levels of hAMSC co-cultured with lymphocyte at a ratio of 1:1 after 72 hours were measured by ELISA, and the level of IFN-γ was significantly lower than that in the same co-culture system of hBMMSC. In contrast to the IFN-γ in the PHA-stimulated group, the IFN-γ level in both co-culture groups was significantly lower.

CONCLUSIONMSC from amnion displayed a higher proliferative capacity and stem cell properties, compared with hBMMSC. Both MSC can inhibit lymphocyte proliferation and suppress IFN-γ secretion induced by PHA in vitro.

Amnion ; cytology ; Bone Marrow Cells ; cytology ; Cell Proliferation ; Cells, Cultured ; Coculture Techniques ; Hematopoietic Stem Cells ; cytology ; Humans ; Immunophenotyping ; Immunosuppression ; Lymphocyte Activation ; Mesenchymal Stromal Cells ; cytology ; T-Lymphocytes ; cytology

This study was aimed to investigate the immunomodulatory ability of human umbilical cord mesenchymal stem cells (UB-MSC) along with prolonging of culture time and increasing of passages in vitro. Mesenchymal stem cells (MSC) were isolated from human umbilical cord and cultured in vitro. The morphological changes and nucleocytoplasmic ratio of MSC were observed using Giemsa staining. MSC of the 5th passage were selected as control group, and MSC of the 13th passage were taken as senile group. The degree of cell senescence was detected by aging cells in situ test kit. Cell Counting Kit-WST-8 was used to determine the proliferation of lymphocytes in mixed lymphocytes coculture system with different passages of MSC. The expression of immunomodulation-related genes was detected by RT-PCR. The results showed that the length-breadth ratio of MSC increased and nucleocytoplasmic ratio decreased along with the increasing of passages. The senium degree of cells of the 13th passage was higher than that of the 5th passage cells. The capacity of suppressing lymphocyte proliferation of the 13th passage MSC was enhanced, compared with the 5th passage. Moreover, the expression of immunosuppression-related genes of senile MSC increased and the expression of most anti-inflammation associated genes declined as compared with young MSC by RT-PCR. It is concluded that the degree of MSC senescence gradually develops with increasing of culture passage, but the immunosuppressive ability of MSC strengthens with continuous culture.
Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Cellular Senescence ; Humans ; Lymphocytes ; cytology ; immunology ; Mesenchymal Stromal Cells ; cytology ; immunology ; Umbilical Cord ; cytology