CD4(+)CD25(+)CD127(dim/-) regulatory T cells (Tregs) have been implicated in suppressing T cell immune responses to hepatitis B virus (HBV), but the inhibition mechanism has not being clear yet. This study investigated the effects of soluble FGL2 (sFGL2) secreted by Tregs on immune suppression in chronic HBV-infected patients. We verified that sFGL2 protein and mRNA were highly expressed in Tregs. The separated Tregs by using magnetic beads from peripheral blood mononuclear cells (PBMCs) in 20 patients with chronic hepatitis B were co-cultured with PBMCs at a ratio of 1:3 with anti-CD3 stimulating antibody or FGL2 blocking antibody. The proliferation index of CD8(+)T cells after blocking FGL2 was higher than that in blank group (3.58±0.18 vs. 3.28±0.17, P=0.034) in 18 of 20 samples, and lower than that in CD3 stimulation group (3.82±0.19, P=0.026) in 16 of 20 samples. The IFN-γ secreted in the mixed culture in the absence of Tregs was higher than that in the culture in the presence of Tregs, but it could be abolished by FGL2 blocking antibody. These results suggest that sFGL2 protein secreted by Tregs suppresses the proliferation and function of CD8(+) T cells in chronic hepatitis B.
CD8-Positive T-Lymphocytes ; immunology ; metabolism ; Cells, Cultured ; Fibrinogen ; immunology ; metabolism ; Hepatitis B, Chronic ; immunology ; metabolism ; Humans ; T-Lymphocytes, Regulatory ; immunology ; metabolism

Animals ; Antigens, CD ; immunology ; Cytokines ; metabolism ; Hepacivirus ; immunology ; Hepatitis C ; immunology ; prevention & control ; virology ; Hepatitis C Antibodies ; biosynthesis ; immunology ; Hepatitis C Antigens ; immunology ; Humans ; Killer Cells, Natural ; immunology ; T-Lymphocytes ; immunology ; metabolism ; T-Lymphocytes, Regulatory ; immunology ; metabolism ; Viral Proteins ; immunology

T-cell receptor (TCR)-engineered T cells are a novel option for adoptive cell therapy used for the treatment of several advanced forms of cancer. Work using TCR-engineered T cells began more than two decades ago, with numerous preclinical studies showing that such cells could mediate tumor lysis and eradication. The success of these trials provided the foundation for clinical trials, including recent clinical successes using TCR-engineered T cells to target New York esophageal squamous cell carcinoma (NY-ESO-1). These successes demonstrate the potential of this approach to treat cancer. In this review, we provide a perspective on the current and future applications of TCR-engineered T cells for the treatment of cancer. Our summary focuses on TCR activation and both pre-clinical and clinical applications of TCR-engineered T cells. We also discuss how to enhance the function of TCR-engineered T cells and prolong their longevity in the tumor microenvironment.
Animals ; Antigens, Neoplasm ; immunology ; metabolism ; Humans ; Neoplasms ; immunology ; metabolism ; Receptors, Antigen, T-Cell ; genetics ; metabolism ; T-Lymphocytes ; immunology ; metabolism

T cell recognition of foreign peptide antigen and tolerance to self peptides is key to the proper function of the immune system. Usually, in the thymus T cells that recognize self MHC + self peptides are deleted and those with the potential to recognize self MHC + foreign peptides are selected to mature. However there are exceptions to these rules. Autoimmunity and allergy are two of the most common immune diseases that can be related to recognition of self. Many genes work together to lead to autoimmunity. Of those, particular MHC alleles are the most strongly associated, reflecting the key importance of MHC presentation of self peptides in autoimmunity. T cells specific for combinations of self MHC and self peptides may escape thymus deletion, and thus be able to drive autoimmunity, for several reasons: the relevant self peptide may be presented at low abundance in the thymus but at high level in particular peripheral tissues; the relevant self peptide may bind to MHC in an unusual register, not present in the thymus but apparent elsewhere; finally the relevant self peptide may be post translationally modified in a tissue specific fashion. In some types of allergy, the peptide + MHC combination may also be fully derived from self. However the combination in question may be modified by the presence of other ligands, such as small drug molecules or metal ions. Thus these types of allergies may act like the post translationally modified peptides involved some types of autoimmunity.
Animals ; Autoantigens ; immunology ; Autoimmunity ; HLA Antigens ; immunology ; Humans ; Hypersensitivity ; immunology ; Receptors, Antigen, T-Cell ; metabolism ; T-Lymphocytes ; immunology ; metabolism

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

Crystallography, X-Ray ; Receptors, Antigen, T-Cell ; chemistry ; immunology ; metabolism ; T-Lymphocytes ; immunology ; metabolism

BACKGROUNDPrevious studies indicate that CD43 plays a role in regulating the adhesion of lymphocytes, cell mutation and activation, however, little is known about its effect on systemic lupus erythematosus (SLE). This study was designed to explore the clinical significance of CD43 in SLE patients.

METHODSWe used microarray and real-time PCR to detect the mRNA and protein expression of magnetic bead sorted T cells and B cells from peripheral blood mononuclear cells (PBMCs) of SLE patients, and analyzed the relationship between CD43 and the clinical indexes.

RESULTSBoth microarray and real-time PCR results showed that CD43 mRNA was significantly decreased in PBMCs of SLE patients compared with healthy controls (P < 0.001). There were no significant differences between lupus nephritis and non-lupus nephritis patients, and neuropsychiatric and non-neuropsychiatric patients. CD43 mRNA expression was significantly reduced in T cells but not in B-cells in SLE patients compared to healthy controls (P < 0.01). Compared with healthy controls, the percentage of CD43(+) cells in the PBMCs of SLE was significantly decreased (P = 0.004), and the CD43 fluorescence intensity in CD3(+)/CD43(+) cells and CD19(+)/CD43(+) cells was also significantly weaker than in healthy controls (P = 0.039 and 0.003). There was no significant difference in the percentage of CD3(+)/CD43(+) cells, CD19(+)/CD43(+) cells between the two groups. The CD43 fluorescence intensity in CD3(+)/CD43(+) cells was inversely correlated with the levels of IgG and IgM (r = -0.8 and -0.6).

CONCLUSIONSCompared to healthy controls, both CD43 mRNA and protein expressions were reduced in T cells from patients with SLE, and were inversely correlated with IgG.

B-Lymphocytes ; immunology ; metabolism ; Humans ; Leukocytes, Mononuclear ; Leukosialin ; genetics ; metabolism ; Lupus Erythematosus, Systemic ; immunology ; metabolism ; Oligonucleotide Array Sequence Analysis ; Real-Time Polymerase Chain Reaction ; T-Lymphocytes ; immunology ; metabolism

The study was aimed to establish a new method of preparation of human placenta factor (PF) and to determine its physic-chemical properties, as well as effects on lymphocytes in vitro. PF was prepared by ultrafiltration. The contents and molecular weight of all constitutions were determined by Bradford method and SDS-PAGE, respectively. Cyclosporin A (CsA) was served as positive control, normal saline (NS) was used as negative control. PHA-stimulated lymphocyte proliferation and mixed lymphocyte reaction (MLR) were detected with MTT assay. The expression of CD69 on T cells was analyzed by flow cytometry. Cytotoxicity of natural killer (NK) cells against K562 tumor cells was examined with LDH release assay. The results indicated that PF was determined to be a group of low molecular weight polypeptides, consisting of two major components whose molecular weight were 9.187 and 4.794 kD respectively. The contents of PF were 5.7 - 6.9 mg/g fresh placenta. PF had similar suppressive effects on PHA-stimulated lymphocyte proliferation and MLR in vitro as compared with CsA (P > 0.05). Both PF and CsA could downregulate the expression of CD69 on T cells which had been stimulated by PMA plus ionomycin (PF vs CsA, P > 0.05). The cytotoxicity of NK cells against K562 cells in PF group was slightly higher or equivalent as compared with that in NS group (P > 0.05), but the cytotoxicity in CsA group was much lower than that in NS group (P < 0.05). It is concluded that a new method of preparation of PF has been established. This study first demonstrates that PF has strong immunosuppressive effects on T cell in vitro, and suppresses T cell proliferation and activation induced by mitogen and alloantigen. This study indicats that PF has no any inhibitory effects, but even enhances the cytotoxicity of NK cells against K562 tumor cells. These results suggest that PF may have suppressive effects on graft-versus-host disease (GVHD) without diminishing graft-versus-tumor (GVT) effects. Therefore, PF may probably be an ideal and promising agent against GVHD.
Cyclosporine ; pharmacology ; Ferritins ; immunology ; isolation & purification ; Graft vs Host Disease ; metabolism ; prevention & control ; Humans ; Immunosuppressive Agents ; immunology ; K562 Cells ; Killer Cells, Natural ; immunology ; Lymphocytes ; immunology ; T-Lymphocytes ; immunology

UNLABELLEDTo investigate the effect of immune response mediated by the T cells stimulated with the specific antigen (oxidized low-density lipoprotein, oxLDL) on plaque stability in coronary heart disease.

METHODSThis study involved 20 patients with acute myocardial infarction (AMI), 34 with unstable angina pectoris (UAP), 27 with stable angina pectoris (SAP) and 22 healthy control subjects. With MTS/PMS colorimetric assay, the T cells from all the subjects were tested for proliferative response to stimulation by 5 microg/ml oxLDL and 5 microg/ml low-density lipoprotein (LDL). Interferon-gamma (IFN-gamma) concentration in the proliferative response of the T cells was measured with enzyme-linked immunosorbent assay (ELISA).

RESULTSThe proliferative response of the T cells elicited by 5 microg/ml oxLDL stimulation was significantly higher in the AMI and UAP groups than in the SAP and control groups (P<0.05). Similarly, IFN-gamma concentration in the proliferative response of the T cells to 5 microg/ml oxLDL stimulation was significantly higher in the former two groups (P<0.05). In the AMI and UAP groups, 5 microg

CONCLUSIONThe immune response mediated by the T cells to specific antigen stimulation, especially the immune response mediated by T helper type 1 (Th1) cells secreting IFN-gamma, may play an important role in the plaque instability and the occurrence of acute coronary syndrome.

Aged ; Coronary Disease ; immunology ; Female ; Humans ; Interferon-gamma ; secretion ; Lipoproteins, LDL ; immunology ; Male ; Middle Aged ; T-Lymphocytes ; immunology ; metabolism ; T-Lymphocytes, Helper-Inducer ; immunology ; metabolism

PURPOSE: Forkhead box p3 (Foxp3) positive T regulatory cells (Tregs) have a functionally immunosuppressive property that prevents effector cells from acting against self in autoimmune diseases or a tumor. It is known that Tregs may be highly relevant in cancer progression. Dendritic cells (DCs) induce cutaneous immune response, however several studies have suggested that DCs are involved in immunosuppression. The aim of this study is to evaluate the prevalence of Tregs and DCs infiltration in cutaneous premalignant and malignant squamous lesions. MATERIALS AND METHODS: We evaluated Tregs and DCs in skin tissue samples obtained from 83 patients with actinic keratosis, Bowen's disease or squamous cell carcinoma by immunohistochemistry. RESULTS: The prevalence of Tregs and DCs was significantly higher in squamous cell carcinoma and Bowen's disease than in actinic keratosis. In addition, the number of DCs was closely correlated with the prevalence of Tregs, and DCs were also located in direct proximity to Tregs. CONCLUSION: Tregs is related to cutaneous squamous tumor progression.
Bowen's Disease/immunology/metabolism/pathology ; Carcinoma, Squamous Cell/immunology/metabolism/pathology ; Dendritic Cells/immunology/metabolism/pathology ; Forkhead Transcription Factors/immunology/*metabolism ; Humans ; Immune Tolerance ; Keratosis, Actinic/immunology/metabolism/pathology ; Skin Neoplasms/*immunology/metabolism/pathology ; T-Lymphocytes, Regulatory/*immunology/metabolism/pathology