The autoantigenic epitopes carried by the platelet glycoprotein in patients with idiopathic thrombocytopenic purpura (ITP) have been observed to localize on the specific regions of glycoprotein. There is a limited number of autoantigenic epitopes on the respective glycoproteins. The clonal B-cell and/or T cell expansion have been detected in some patients with ITP, and the autoantibodies is clonally derived. This research is of clinical importance since identification of clonally derived autoantibodies not only may help to discover the pathogenesis of ITP but also lead to less toxic and more specific therapies. In this review, the clonal limitation of autoantibody and clonal expansion of B-lymphocyte is ITP, clonal characteristics of T-lymphocyte in ITP, and significance of research on clones in ITP were discussed and summarized.
Autoantibodies ; immunology ; B-Lymphocytes ; immunology ; Epitopes ; Humans ; Purpura, Thrombocytopenic, Idiopathic ; etiology ; immunology ; T-Lymphocytes ; immunology

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

The Notch signaling pathway is conserved from Drosophila to mammals and is critically involved in developmental processes. In the immune system, it has been established that Notch signaling regulates multiple steps of T and B cell development in both central and peripheral lymphoid organs. Relative to the well documented role of Notch signaling in lymphocyte development, less is known about its role in regulating myeloid lineage development and function, especially in the context of acute and chronic inflammation. In this review article, we will describe the evidence accumulated during the recent years to support a key regulatory role of the Notch pathway in innate immune and inflammatory responses and discuss the potential implications of such regulation for pathogenesis and therapy of inflammatory disorders.
Animals ; B-Lymphocytes ; immunology ; pathology ; Humans ; Inflammation ; immunology ; pathology ; Receptors, Notch ; immunology ; Signal Transduction ; immunology ; T-Lymphocytes ; immunology ; pathology

B cell activated co-receptor plays important roles in linkage of innate and acquired humoral immune responses. CD21 molecule in the co-receptor complex is a receptor for C3dg and CD19 molecule enhances BCR signal transduction. CD21 also expresses on the surface of follicular dendritic cells, which mediates the long-term maintenance of antigens and is indispensable for maintaining the memory of B cells. B cell activated co-receptor also has an effect on the negative selection of B cells reactive to autoantigens.
Animals ; Antigens, CD19 ; immunology ; Autoantigens ; immunology ; B-Lymphocytes ; immunology ; Humans ; Receptors, Complement 3d ; immunology ; Receptors, Immunologic

Epitopes, T-Lymphocyte ; immunology ; HLA Antigens ; immunology ; Hepatitis B virus ; immunology ; Humans ; T-Lymphocytes, Cytotoxic ; immunology

T cell immunity and phagocytic activity were studied in the blood of patients with IgA nephropathy in order to clarify their roles in the pathogenesis of IgA nephropathy. The percentages of total T lymphocytes, helper T cell and suppressor T cells were significantly reduced in patients. A significantly elevated helper T cell/suppressor T cell ratio in patients showed a predominant reduction in suppressor T cells. There was a significant relationship between histologic findings and helper T cell/suppressor T cell ratio in patients. Natural Killer (NK) cell activity was significantly reduced but the lymphocyte response after phytohemagglutinin (PHA) stimulation was not in patients. ConA-induced suppressor cell activity was not depressed despite of a decrease in suppressor T cells in patients. Phagocytic activity of polymorphonuclear leucocytes (PMNs) ingesting yeasts was significantly reduced in patients. Also an inverse correlation was found between serum IgA levels and phagocytic activity of PMN. It is concluded that suppressor T cell defects, depressed phagocytic activity and impaired NK cell activity may play a role in the pathogenesis of IgA nephropathy.
B-Lymphocytes/immunology ; Glomerulonephritis, IGA/*immunology/pathology ; Humans ; Killer Cells, Natural/immunology ; Neutrophils/immunology ; *Phagocytosis ; T-Lymphocytes/*immunology ; T-Lymphocytes, Regulatory/immunology

Autoimmune postpartum thyroiditis (PPT) has been thought of as one of the organ-specific autoimmune diseases. The present study was designed to investigate whether the immunological changes during the postpartum period might induce this disease, by comparing the circulating lymphocyte subsets and antibody-dependent cell-mediated cytotoxicity (ADCC) between normal postpartum women and PPT patients. The results were as follows: 1) No significant differences in the circulating total T lymphocyte population, or suppressor T lymphocyte subsets, or in Th/Ts ratio were found among 25 PPT patients, 11 normal postpartum women and 11 normal non-pregnant women. 2) In PPT patients, helper T lymphocyte subsets were fewer in proportion than those of normal postpartum or non-pregnant women. However, B lymphocyte population (19.7 +/- 7.8%) and ADCC activity (.41 +/- 13) in PPT patients were comparable to those in normal postpartum women (18.3 +/- 4.8%, .42 +/- .11), although they were significantly greater than those in normal normal non-pregnant women (13.3 +/- 5.9%, .29 +/- .07). In conclusion, the enhancement of immune activities observed in PPT patients was comparable to that in normal postpartum women, suggesting that some other causative or triggering factors might be responsible for the occurrence of this disease.
Adult ; Antibody-Dependent Cell Cytotoxicity ; B-Lymphocytes/immunology ; Female ; Human ; Pregnancy ; Puerperal Disorders/immunology* ; T-Lymphocytes/immunology ; Thyroiditis, Autoimmune/immunology*

B cell activating factor (BAFF) is one of the TNF family member, regulates the survival and maturation of B lymphocyte. BAFF binds to three receptors: BCMA, TACI and BAFF-R. In recent years, studies have revealed important roles of BAFF and its receptors in immune regulation of antibody isotype switching, germinal center maintenance, and T cell co-stimulation, that may provide new drugs in the future for the treatment of autoimmune disorders, lymphoma and B cell immunodeficiencies. Therefore, the structure, expression, receptors, biological function and clinical application of BAFF are briefly summarized in this review.
B-Cell Activating Factor ; immunology ; B-Cell Activation Factor Receptor ; immunology ; B-Cell Maturation Antigen ; immunology ; B-Lymphocytes ; immunology ; Humans ; Immunity ; Transmembrane Activator and CAML Interactor Protein ; immunology

Hepatitis B Core Antigens ; immunology ; Hepatitis B virus ; genetics ; immunology ; Hepatitis B, Chronic ; virology ; Humans ; T-Lymphocytes, Cytotoxic ; immunology

CD8-Positive T-Lymphocytes ; immunology ; Dendritic Cells ; immunology ; Hepatitis B ; immunology ; therapy ; Hepatitis B Surface Antigens ; immunology ; Humans