Mesenchymal stem cells (MSCs) can inhibit T cell proliferation, the effects of MSCs on various T cell subsets have showed different immune regulatory reactions, and their mechanisms mainly include cell-cell contact and mediation by cytokines secreted from MSCs. Encouragingly, recent studies have showed that the effects of MSCs on T-cell response to pathogens is not significant, but can obviously suppress T cell response to allogeneic antigens. In addition, MSCs can regulate the proliferation, survival, antibody secretion and differentiation of B cells, inhibit the production, proliferation, migration and antigen-presentation of DCs, and modulate the differentiation and maturation of DCs, and regulate the proliferation, cell toxicity and cytokine secretion of NK cells. In this review, the research advances on immunomodulatory effects of MSCs on various immune cells including T-lymphocytes, B-lymphocytes, NK cells and DCs are summarized with emphasis on the immunoregulatory effects of MSCs on T-lymphocytes.
B-Lymphocytes ; immunology ; Dendritic Cells ; immunology ; Humans ; Killer Cells, Natural ; immunology ; Mesenchymal Stromal Cells ; cytology ; immunology ; T-Lymphocytes ; immunology

In an attempt to study the immunoregulatory effect of osteoblasts derived from mesenchymal stem cells (MSC), MSC was induced to differentiate into osteoblasts for one week. The growth pattern and the phenotype were evaluated by MTT and flow cytometry respectively. The immunoregulatory effect was tested by the inhibitory effect on T cell proliferation. The result showed that during the differentiation cells grew fast and there was no significant change in the phenotypes but keeping CD73, CD105, CD44, CD29 positive and CD34, CD45, HLA-DR, CD86 negative. Osteocyte derived from MSC also showed immunosuppressive effect on T cell proliferation in adose-dependent manner. It is concluded that osteoblasts derived from MSC also harbored immunoregulatory effect.
Bone Marrow Cells ; cytology ; immunology ; Cell Differentiation ; immunology ; Cell Lineage ; Cell Proliferation ; Cells, Cultured ; Humans ; Mesenchymal Stromal Cells ; cytology ; immunology ; Osteoblasts ; cytology ; immunology ; T-Lymphocytes ; 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

OBJECTIVETo explore the specific anti-leukemia immune response of CD8+ cytotoxic T lymphocyte (CTL) derived from cord blood (CB) ex vivo and evaluate the feasibilities and values of the CTL for specific immunotherapy.

METHODSDendritic cells (DC) were induced from mononuclear cells (MNC) by combination cytokines in 10 CB samples. Loading U937 cell lysate antigen on the mature DC, they could stimulate the lymphocytes of the same origin to generate CTL. MidiMACS was used to isolate CD8+ CTL. Analysis of DC was performed by inverted microscopy, scanning electron microscopy and flow cytometry. Methyl thiazolyl tetrazolium (MTT) assay was used to evaluate the cytotoxicity of the CTL.

RESULTSCocultured with GM-CSF, IL-4, TNF-alpha and PGE2, CB-MNC could be induced into functional DC with typical morphology. The mean cytotoxicity of CD8+ CTL to U937 cells was significant stronger than that of CD8- CTL and TL at the same E: T ratios. The mean cytotoxicity rate of CD8+ CTL to U937 cells was higher than that to K562 cells [(66.36 +/- 12.43)% vs (41.97 +/- 14.24)%] at E: T ratio of 40: 1 (P < 0.05). The cytotoxicity of CD8- CTL to K562 cells showed no difference from that to U937 cells (P > 0.05).

CONCLUSIONMature CB-DC loading U937 cell antigens could induce CB-T lymphocytes to generate leukemia-specific CD8+ CTL. The cytotoxicity of the CD8+ CTL is specific against U937 cells and is more potent than that of CD8- CTL.

CD8-Positive T-Lymphocytes ; cytology ; immunology ; Dendritic Cells ; cytology ; immunology ; Fetal Blood ; cytology ; immunology ; Humans ; In Vitro Techniques ; K562 Cells ; T-Lymphocytes, Cytotoxic ; immunology ; U937 Cells

Dendritic cells (DCs) are important immune cells linking innate and adaptive immune responses. DCs encounter various self and non-self antigens present in the environment and induce different types of antigen specific adaptive immune responses. DCs can be classified into lymphoid tissue-resident DCs, migratory DCs, non-lymphoid resident DCs, and monocyte derived DCs (moDCs). Recent work has also established that DCs consist of developmentally and functionally distinct subsets that differentially regulate T lymphocyte function. The development of different DC subsets has been found to be regulated by a network of different cytokines and transcriptional factors. Moreover, the response of DC is tightly regulated to maintain the homeostasis of immune system. MicroRNAs (miRNAs) are an important class of cellular regulators that modulate gene expression and thereby influence cell fate and function. In the immune system, miRNAs act at checkpoints during hematopoietic development and cell subset differentiation, they modulate effector cell function, and are implicated in the maintenance of homeostasis. DCs are also regulated by miRNAs. In the past decade, much progress has been made to understand the role of miRNAs in regulating the development and function of DCs. In this review, we summarize the origin and distribution of different mouse DC subsets in both lymphoid and non-lymphoid tissues. The DC subsets identified in human are also described. Recent progress on the function of miRNAs in the development and activation of DCs and their functional relevance to autoimmune diseases are discussed.
Animals ; Autoimmune Diseases ; immunology ; Cell Differentiation ; immunology ; Dendritic Cells ; cytology ; immunology ; Humans ; MicroRNAs ; immunology ; Monocytes ; cytology ; immunology ; T-Lymphocytes ; cytology ; immunology

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

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

The myelodysplastic syndromes (MDS) comprises a heterogeneous group of clonal hematopoietic stem cell disorders, while immunological abnormalities are frequently observed in such patients. T-cell mediated suppression of hematopoietic precursors contributes to the cytopenia and is related to the initiation and development of myelodysplastic syndromes (MDS). In this review, current knowledge concerning the feature of T-cell clonal expansion in MDS based on the analysis of T-cell receptor repertoire is summarized, including following issues: autoimmunity in MDS patients associated with T-cell mediated suppression of hematopoiesis, characteristics of T-cell clonal expansion in MDS patients, change of T-cell repertoire and recent thymus output function in MDS patients, efficiency of immunosuppressive treatment associated with T-cell clonal expansion in MDS patients and significance of T-cell clonal analysis in clinical application.
Clone Cells ; Humans ; Myelodysplastic Syndromes ; immunology ; Receptors, Antigen, T-Cell ; immunology ; T-Lymphocytes ; cytology ; immunology

The study was purposed to explore the quantity, morphology and immunophenotype of dendritic cells (DC) acquired by co-cultivated system with 3 types of cytokines and sodium selenite (Se) from peripheral blood mononuclear cells (PBMNCs), and to investigate the effects of Se on inducing the cytotoxic T lymphocyte (CTL) to get specific anti-leukemic activity in vitro by DC pulsed with K562 cell frozen-thawed antigen (antigen cell loading). PBMNCs isolated from healthy donors were cultured in RPMI 1640 medium contained 10% FBS supplied with 3 cytokines (rhGM-CSF, rhIL-4, TNF-alpha) for 4 days, DCs harvested were divided into 4 groups, DCI: DC alone; DCII: DC + Se (adding 0.5 micromol/L of Se); DCIII: DC + K562 (pulsed with lysed K562 cells); DCIV: DC + Se + K562. Morphology of DCs was observed under microscope at day 7. The CD1a, CD40, CD83, and CD86 were detected by FCM. Cytotoxicity of T cells induced by DC were measured with LDH release test at day 12. The level of IL-12 in supernatant of cultured DCs were determined with ELISA. The results indicated that at 7th day DC in 4 groups showed characteristic morphology, the colony numbers of 4 groups were all higher than those before cultivation. There were no obvious differences of morphology and colony counts between DCI group and DCII group. The colony numbers of DCIII group and DCIV group increased, as well as the ratio of suspended cells enhanced. The expressions of CD1a, CD40, CD83 and CD86 in 4 groups of DC were significantly higher than those in PBMNC group (p < 0.01), the expressions of CD1a and CD40 in 4 groups of DC did not display significant difference (p > 0.05), the expressions of CD83 and CD86 in both DCIII group and DCIV group were all higher than those in DCI group and DCII group (p < 0.01), but their expressions of CD83 and CD86 in DCI and DCII were not significantly different (p > 0.05), as well as those in DCIII group and DCIV group. With the ratio of 25:1 between E:T, killing rate of CTL on K562 cells in 4 DC groups were 15.3 +/- 2.3%, 26.3 +/- 3.7%, 28.2 +/- 4.5% and 36.2 +/- 3.7% respectively, all obviously higher than those of T cell group without being sensitized by DCs (5.9 +/- 2.4%) (p < 0.01), The CTL effect in DCIV group was the highest, which was higher than those in other 3 DC groups (p < 0.01); the effects in both DCII and DCIII group were also higher than that in DCI group (p < 0.01), but their difference between DCII and DCIII groups did not show significance (p > 0.05). The levels of IL-12 in supernatant of DCI, DCII, DCIII and DCIV groups were 257.0 +/- 64.2, 328.1 +/- 43.9, 323.0 +/- 53.5 and 353.9 +/- 46.2 pg/ml respectively, all significantly higher than that in supernatant of T cell alone group without being sensitized by DCs (35.27 +/- 27.1 pg/ml) (p < 0.01), The levels in DCII, DCIII and DCIV groups were all higher than that in DCI group (p < 0.01), but their levels between DCII, DCIII and DCIV groups were not of significant difference (p > 0.05). It is concluded that matured DCs can be successfully obtained from PBMNCs by a culture system contained rhGM-CSF, rhIL-4 and TNF-alpha with or without low-dose of Se (0.5 micromol/L) in vitro. Using K562 cell frozen-thawed antigen, DC express more adhesive molecules and co-stimulating molecules (CD83, CD86), and increase the secretion of IL-12, as well as the killing effects of CTL on special target cells. Low dose of Se did not showed effects on quantity and morphology of matured DC harvested, as well as their expression of mature phenotypes, it raised levels of IL-12 secreted by DCs, reaching the same level as using K562 cell frozen-thawed antigen, and it showed synergistic effect on induction of CTL with K562 cell frozen-thawed antigen.
Cells, Cultured ; Cytokines ; pharmacology ; Dendritic Cells ; cytology ; immunology ; Humans ; K562 Cells ; Leukocytes, Mononuclear ; cytology ; Sodium Selenite ; pharmacology ; T-Lymphocytes ; immunology ; T-Lymphocytes, Cytotoxic ; cytology ; immunology

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