B cell linker (BLNK) is a key linker protein of B cell receptor (BCR) signaling pathway. BLNK participates in the regulation of PLC-γactivity and the activation of Ras pathway through its typical structure and interaction network with other proteins, and is thus widely involved in the regulation of B cell proliferation, differentiation, apoptosis and signal transduction. Furthermore, it is closely related to anaphylactic diseases, multiple sclerosis, chromosomal aneuploidy, aneuglobulinemia, B lymphocytic leukemia and lymphoma. Herein we review the structure and biological function of BLNK and its role in B cell-related diseases. BLNK can cooperate with a series of effective proteins to activate BCR signaling pathway, thereby regulating the development, maturation and function of B cells. The functional mutation of BLNK can destroy the homeostasis of B cells and affect the development and maturation of B cells, which leads to the occurrence of B cell related diseases. A comprehensive understanding of the biological functions of BLNK not only provides insights into the pathogenesis of B cell-related diseases, but also inspires new ideas and helps to find breakthroughs for the treatment of these diseases with BLNK as the therapeutic target.
Adaptor Proteins, Signal Transducing ; chemistry ; genetics ; physiology ; Apoptosis ; B-Lymphocytes ; cytology ; physiology ; Cell Differentiation ; Cell Proliferation ; Humans ; Mutation ; Receptors, Antigen, B-Cell ; chemistry ; physiology ; Signal Transduction ; Structure-Activity Relationship

Theileria annulata is a tick-borne intracellular protozoan parasite that causes tropical theileriosis, a fatal bovine lymphoproliferative disease. The parasite predominantly invades bovine B lymphocytes and macrophages and induces host cell transformation by a mechanism that is not fully comprehended. Analysis of signaling pathways by quantitative real-time PCR (qPCR) could be a highly efficient means to understand this transformation mechanism. However, accurate analysis of qPCR data relies on selection of appropriate reference genes for normalization, yet few papers on T. annulata contain evidence of reference gene validation. We therefore used the geNorm and NormFinder programs to evaluate the stability of 5 candidate reference genes; 18S rRNA, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ACTB (β-actin), PRKG1 (protein kinase cGMP-dependent, type I) and TATA box binding protein (TBP). The results showed that 18S rRNA was the reference gene most stably expressed in bovine PBMCs transformed and non-transformed with T. annulata, followed by GAPDH and TBP. While 18S rRNA and GAPDH were the best combination, these 2 genes were chosen as references to study signaling pathways involved in the transformation mechanism of T. annulata.
Animals ; B-Lymphocytes/parasitology ; Cattle ; Cell Line ; Cells/*parasitology ; Cells, Cultured ; Gene Expression Profiling ; Host-Parasite Interactions/*genetics ; Real-Time Polymerase Chain Reaction/*veterinary ; Reproducibility of Results ; Signal Transduction/*genetics ; Theileria annulata/physiology ; Theileriasis/*physiopathology

The complement system is part of the innate immune response and as such defends against invading pathogens, removes immune complexes and damaged self-cells, aids organ regeneration, confers neuroprotection, and engages with the adaptive immune response via T and B cells. Complement activation can either benefit or harm the host organism; thus, the complement system must maintain a balance between activation on foreign or modified self surfaces and inhibition on intact host cells. Complement regulators are essential for maintaining this balance and are classified as soluble regulators, such as factor H, and membrane-bound regulators. Defective complement regulators can damage the host cell and result in the accumulation of immunological debris. Moreover, defective regulators are associated with several autoimmune diseases such as atypical hemolytic uremic syndrome, dense deposit disease, age-related macular degeneration, and systemic lupus erythematosus. Therefore, understanding the molecular mechanisms by which the complement system is regulated is important for the development of novel therapies for complement-associated diseases.
Adaptive Immunity ; Antigen-Antibody Complex ; Autoimmune Diseases ; Autoimmunity ; B-Lymphocytes ; Complement Activation ; Complement Factor H ; Complement System Proteins* ; Glomerulonephritis, Membranoproliferative ; Hemolytic-Uremic Syndrome ; Immunity, Innate ; Lupus Erythematosus, Systemic ; Macular Degeneration ; Physiology* ; Regeneration

<b>OBJECTIVEb>To inhibit the proliferation and metastasis of colon cancer cells by increasing the expression level of B-cell translocation gene-2 (BTG2).

<b>METHODSb>Western blot assay was used to detect the expression level of BTG2 protein in the normal intestinal epithelial HIEC cells and three colon cancer cell lines SW620, HT-29 and LS174T. The expression of BTG2 protein in normal colonic epithelial tissue, colon adenoma and colon cancer tissue was detected by immunohistochemistry. The plasmid with BTG2 gene full-length sequence was transfected into colon cancer SW620 cells, and the expression of BTG2 protein was detected by Western blot. The cell growth curve was drawn by MTT test. The Ki-67-positive rate was calculated using immunofluorescence staining. The cell migration of colon cancer cells was detected by scratch test and Transwell double chamber culture system, and the pseudopodia growth of tumor cells was detected by Matrigel 3D culture system.

<b>RESULTSb>Western blot results showed that BTG2 relative expression levels were 0.83 ± 0.12, 0.18 ± 0.04, 0.20 ± 0.05 and 0.36 ± 0.07 in normal human intestinal epithelial cells HIEC, and human colon cancer cell line SW620, HT-29 and LS174T, respectively. The results of immunohistochemistry showed that the positive expression of BTG2 protein in normal colorectal tissue, colorectal adenoma and colorectal carcinoma tissues were 82.5% (33/40), 77.5%(31/40) and 17.5% (7/40), respectively, with a significant difference between two groups (P < 0.05). Immunofluorescence results showed that the positive rate of Ki-67 in the control group, empty vector group and BTG2 transfection group was (76.2 ± 8.0)%, (81.4 ± 9.7)% and (50.1 ± 7.1)%, respectively, showing a significant difference between two groups (P < 0.05). The scratch test results showed that in the control group, empty vector group and BTG2 transfection group, the distance of SW620 cells between two sides was (79.27 ± 11.24) µm, (80.65 ± 12.17) µm and (124.77 ± 19.63) µm, respectively, with a significant difference between two groups (P < 0.05). Transwell results showed that in the control group, empty plasmid group and BTG2 transfection group, the SW620 cell migration rate was (78.5 ± 13.1)%, (73.2 ± 12.9)% and (47.4 ± 9.1)%, respectively, showing a significant difference between two groups (P < 0.05). The number of neurospheres of BTG2 transfection group was decreased SW620, which had poor ductility.

<b>CONCLUSIONSb>BTG2 gene is involved in colon cancer cell proliferation and metastasis, and effectively restores the function of BTG2 protein. Therefore, it may be expected to become a new option in gene therapy for colon cancer.

B-Lymphocytes ; physiology ; Cell Cycle ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; genetics ; Colonic Neoplasms ; Genetic Vectors ; Humans ; Immediate-Early Proteins ; genetics ; Immunohistochemistry ; Plasmids ; Transfection ; Tumor Suppressor Proteins ; genetics

Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, affecting >90% of the adult population. EBV targets B-lymphocytes and achieves latent infection in a circular episomal form. Different latency patterns are recognized based on latent gene expression pattern. Latent membrane protein-1 (LMP-1) mimics CD40 and, when self-aggregated, provides a proliferation signal via activating the nuclear factor-kappa B, Janus kinase/signal transducer and activator of transcription, phosphoinositide 3-kinase/Akt (PI3K/Akt) and mitogen-activated protein kinase pathways to promote cellular proliferation. LMP-1 also induces BCL-2 to escape from apoptosis and gives a signal for cell cycle progression by enhancing cyclin-dependent kinase 2 and phosphorylation of retinoblastoma (Rb) protein and by inhibiting p16 and p27. LMP-2A blocks the surface immunoglobulin-mediated lytic cycle reactivation. It also activates the Ras/PI3K/Akt pathway and induces Bcl-xL expression to promote B-cell survival. Recent studies have shown that ebv-microRNAs can provide extra signals for cellular proliferation, cell cycle progression and anti-apoptosis. EBV is well known for association with various types of B-lymphocyte, T-lymphocyte, epithelial cell and mesenchymal cell neoplasms. B-cell lymphoproliferative disorders encompass a broad spectrum of diseases, from benign to malignant. Here we review our current understanding of EBV-induced lymphomagenesis and focus on biology, diagnosis and management of EBV-associated B-cell lymphoproliferative disorders.
B-Lymphocytes/*pathology/*virology ; Diagnosis, Differential ; Disease Management ; Epstein-Barr Virus Infections/*complications ; Herpesvirus 4, Human/*physiology ; Humans ; Lymphoproliferative Disorders/*diagnosis/*etiology/therapy

<b>OBJECTIVEb>To explore changes of B and T lymphocyte attenuator (BTLA), superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAOC), reactive oxygen species (ROS), reactive nitrogen species (RNS), malondialdehyde (MDA) in ankylosing spondylitis (AS) patients, and the effect of Xinfeng Capsule (XFC) on them.

<b>METHODSb>Totally 120 AS patients were assigned to two groups according to random digit table method, the XFC group (3 XFC pills each time, 3 times a day) and the SASP group (4 SASP tablets each time, twice a day), 60 in each group. All patients were treated for 3 months. Another 60 healthy subjects were recruited as a healthy control group. The expression frequency and activation levels of BTLA were detected using flow cytometry. Serum oxidative stress indices (such as SOD and CAT, TAOC, ROS, RNS, MDA) and contents of cytokines [tumor necrosis factor α (TNF-α), IL-1β, IL-4, and IL-10] were detected using enzyme-linked immunoassay (ELISA). Erythrocyte sedimentation rate (ESR) was detected using Westergren method. High-sensitivity C-reactive protein (Hs-CRP) was detected using HITACHI 7060 type automatic biochemical analyzer. Clinical efficacies of ASAS 20 and BASDAI50 were assessed using VAS. Correlation analysis between scoring for quality of life and BTLA expression frequency was performed.

<b>RESULTSb>(1) Clinical efficacies of ASAS 20 and BASDAI50 were significantly better in the XFC group than in the SASP group (P < 0.01). (2) Compared with the healthy control group, BTLA expressions in the peripheral blood of AS patients decreased significantly (P <0. 05); SOD, CAT, and TAOC values significantly decreased (P < 0.01, P < 0.05); ROS, RNS, and MDA values significantly increased (P < 0.01, P < 0.05); TNF-α, IL-1β, ESR, and Hs-CRP values significantly increased (P < 0.01); IL-4 and IL-10 values decreased significantly (P < 0.01, P < 0.05). (3) Compared with pre-treatment in the same group, BTLA/CD19 + B, BTLA/CD24 + B, SOD, TAOC, IL-4, SF-36 [physical functioning (PF), social functioning (SF), role limitation due to physical problems (RP), role limitation due to emotional problems (RE), body pain (BP), mental health (MH), vitality (VT), general health (GH)] were significantly elevated; ROS, MDA, TNF-α, ESR, Hs- CRP, VAS, BASDAI and BASFI, BAS-G were significantly lower in the peripheral blood of the two groups after treatment (P < 0.01, P < 0.05). Better effect was shown in the XFC group in elevating BTLA/CD19+ B, BTLA/CD24 + B, SOD, TAOC, IL-10, BP, MH, VT, and SF; and lowering ROS, IL-1β, MDA, TNF-α, ESR, Hs-CRP, VAS, BASDAI, BASFI, and BAS-G (P < 0.01, P < 0.05). (4) Pearson correlation analysis showed, BTLA/CD19 + B expression of the peripheral blood was positively correlated with SOD, CAT, TAOC, IL-4, IL-10, GH, RP, BP, and SF (r = 0.431, 0.325, 0.318, 0.316, 0.348, 0.314, 0.358, 0.318, 0.326, respectively, P < 0.05, P < 0.01), while it was negative correlated with ROS, MDA, TNF-α, IL-1β, ESR, VAS, and BASDAI (r = -0.342, -0.368, -0.334, -0.354, -0.324, -0.372, -0.342, respectively, P < 0.05, P < 0.01). BTLA/CD24 B expression of the peripheral blood was positively correlated with SOD, TAOC, IL-4, IL-10, GH, RP, BP, SF, RE, MH, VT (r = 0.358, 0.352, 0.372, 0.436, 0.435, 0.326, 0.352, 0.345, 0.326, 0.343, 0.332, respectively, P < 0.05, P < 0.01), while it was negative correlated with ROS, RNS, MDA, ESR, Hs-CRP, VAS, BASDAI, and BASFI (r = -0.447, -0.336, -0.405, -0. 395, -0. 358, -0.436, -0.338, -0.425, respectively, P < 0.05, P < 0.01).

<b>CONCLUSIONb>XFC could improve BTLA expression in the peripheral blood of AS patients, negatively regulate activation and proliferation of B cells, and reduce abnormal immune responses and oxidative stress injury, thereby effectively alleviating joint stiffness and pain.

B-Lymphocytes ; physiology ; Blood Sedimentation ; C-Reactive Protein ; metabolism ; Capsules ; Catalase ; metabolism ; Cytokines ; Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Flow Cytometry ; Humans ; Interleukin-10 ; metabolism ; Interleukin-1beta ; metabolism ; Interleukin-4 ; metabolism ; Malondialdehyde ; metabolism ; Oxidative Stress ; Quality of Life ; Reactive Oxygen Species ; Spondylitis, Ankylosing ; drug therapy ; Superoxide Dismutase ; metabolism ; T-Lymphocytes ; physiology ; Tumor Necrosis Factor-alpha ; metabolism

Epstein-Barr virus (EBV) is a human herpesvirus associated with important human diseases, including infectious mononucleosis syndrome, malignant lymphoma, and nasopharyngeal carcinoma. The mechanism of EBV entry into host cells remains a subject of intensive research. After decades of study, researchers have identified several key proteins and different patterns of EBV intrusion into host cells. The viral surface glycoproteins, gp350/220, gp42, gB, gH, and gL, are involved in interactions with the CR2 receptor on the surface of B lymphocytes during viral entry. However, the majority of epithelial cells lack CR2 receptor expression, which makes viral invasion much more complex than in B lymphocytes. Three different models have been proposed to explain how EBV enters epithelial cells: (1) "transfer of infection", mediated by B lymphocytes or Langerhans cells; (2) EBV utilizes its own proteins during the process of fusion with the cell membrane; and (3) progeny virions arising from EBV-infected epithelial cells cross lateral membranes into adjacent epithelial cells. This review will discuss the relevant mechanism of viral entry into B lymphocytes and epithelial cells during EBV infection.
Animals ; B-Lymphocytes ; virology ; Epithelial Cells ; virology ; Epstein-Barr Virus Infections ; virology ; Herpesvirus 4, Human ; genetics ; physiology ; Humans ; Viral Proteins ; genetics ; metabolism ; Virus Internalization

<b>OBJECTIVEb>To investigate the effect of protein transduction domain-hepatitis B virus core antigen (CTP-HBcAg18-27)-Tapasin fusion protein-induced specific cytotoxic T lymphocyte (CTL) response on hepatitis B virus (HBV) replication in HBV transgenic mice.

<b>METHODSb>Twenty HBV-transgenic mice were randomly divided into two groups for a 3-week course of once weekly subcutaneous immunizations with either CTP-HBcAg18-27-Tapasin fusion protein or CTP-HBcAg18-27. Mice administered isotonic saline served as blank controls. Expressions of cytokines in splenocytes were analyzed by flow cytometry. Serum levels of hepatitis B surface antigen (HBsAg) and HBV DNA were determined by microparticle enzyme immunoassay and real-time fluorescent PCR assay, respectively. Expression of HBsAg in hepatic tissues was detected by immunohistochemistry.

<b>RESULTSb>Immunization with 100 mug of CTP-HBcAg18-27-Tapasin fusion protein led to a significant increase in proportions of CTLs in spleen (2.70%+/-0.20% vs. 50 mug of CTP-HBcAg18-27-Tapasin: 1.66%+/-0.53%, 50 mug of CTP-HBcAg18-27: 1.26%+/-0.56%, and blank controls: 0.75%+/-0.71%; F = 741.45, P = 0.000) and up-regulation of inflammatory cells in hepatic tissue. In addition, both immunizations of CTP-HBcAg18-27-Tapasin led to significant decreases in serum HBsAg and HBV DNA levels compared to those in the CTP-HBcAg18-27 group.

<b>CONCLUSIONb>HBV-related modification of the expression of the molecular chaperone Tapasin may affect its interaction with intracellular antigen peptides, thereby leading to increases the number of specific CTLs in the spleen, decreases in serum HBsAg and HBV DNA levels, and down-regulation of HBsAg expression in hepatic tissue. These results obtained in HBV-transgenic mice suggest that the CTP-HBcAg18-27-Tapasin fusion protein has anti-HBV activity.

Animals ; DNA, Viral ; blood ; Female ; Hepatitis B ; immunology ; Hepatitis B Core Antigens ; genetics ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; physiology ; Male ; Membrane Transport Proteins ; genetics ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Recombinant Fusion Proteins ; genetics ; immunology ; T-Lymphocytes, Cytotoxic ; immunology ; Transfection ; Virus Replication

PURPOSE: The function of regulatory B lymphocytes is known to be abnormal in inflammatory diseases. However, a recent study indicates that IL-10+ B cells seem to be expanded in rheumatoid arthritis (RA). Therefore, the state of IL-10+ B cells in the peripheral blood from RA patients and healthy controls were investigated. MATERIALS AND METHODS: CD19+ cells in peripheral blood mononuclear cells were purified from blood samples of RA patients and age and gender-matched healthy controls, and stimulated with CD40 ligand and CpG for 48 hours. Then, intracellular IL-10 in CD19+ cells was analyzed using flow cytometry. RESULTS: There was no significant difference in the proportion of IL-10+ B cells between 10 RA patients and 10 healthy controls (RA, 0.300+/-0.07 vs. healthy control 0.459+/-0.07, p=0.114). The proportion of induced IL-10+ B cells to total B cells in RA patients was significantly higher than those in controls (RA, 4.44+/-3.44% vs. healthy control 2.44+/-1.64%, p=0.033). However, the proportion of IL-10+ B cells to total B cells correlated negatively with disease activity in RA patients (r=-0.398, p=0.040). Erythrocyte sedimentation rate or C-reactive protein or medication was not associated with the proportion of IL-10+ B cells. CONCLUSION: The proportion of induced IL-10+ B cell increased in RA patients compared to healthy control, however, negatively correlated with disease activity in RA.
Adult ; Aged ; Antigens, CD19/metabolism ; Arthritis, Rheumatoid/blood/*immunology/pathology ; B-Lymphocytes, Regulatory/metabolism/*physiology ; Biological Markers/blood ; Female ; Humans ; Interleukin-10/metabolism ; Male ; Middle Aged ; Severity of Illness Index

Cell death and survival are tightly controlled through the highly coordinated activation/inhibition of diverse signal transduction pathways to insure normal development and physiology. Imbalance between cell death and survival often leads to autoimmune diseases and cancer. Death receptors sense extracellular signals to induce caspase-mediated apoptosis. Acting upstream of CED-3 family proteases, such as caspase-3, Bcl-2 prevents apoptosis. Using short hairpin RNAs (shRNAs), we suppressed Bcl-2 expression in Jurkat T cells, and this increased TCR-triggered AICD and enhanced TNFR gene expression. Also, knockdown of Bcl-2 in Jurkat T cells suppressed the gene expression of FLIP, TNF receptor-associated factors 3 (TRAF3) and TRAF4. Furthermore, suppressed Bcl-2 expression increased caspase-3 and diminished nuclear factor kappa B (NF-kappaB) translocation.
Apoptosis ; Autoimmune Diseases ; Caspase 3 ; Cell Death* ; Gene Expression ; Humans ; NF-kappa B ; Peptide Hydrolases ; Physiology ; Receptors, Death Domain ; RNA, Small Interfering ; Signal Transduction ; T-Lymphocytes* ; TNF Receptor-Associated Factor 4 ; Tumor Necrosis Factor Receptor-Associated Peptides and Proteins