B cell receptor (BCR) is a key molecule involved in B cell specific recognition and the binding of antigens to produce adaptive humoral immune response. Gene rearrangement and high frequency mutation during B cell differentiation are the main mechanisms of BCR diversification. The enormous diversity and unique molecular structure of BCR determine the diversity and specificity of antigen recognition, shaping complex B cell repertoire with extensive collections of antigen specificities. Therefore, BCR antigen-specific information is vital to understanding the adaptive immune characteristics of different diseases. Our ability to connect BCR repertoire and antigen specificity has been enhanced with the development of B cell related research technologies, such as single cell sorting techniques, high-throughput sequencing (HTS), linking B cell receptor to antigen specificity through sequencing (LIBRA-seq). It could help researchers to better understand humoral immune responses, identify disease pathogenesis, monitor disease progression, design vaccines, and develop therapeutic antibodies and drugs. We summarizes recent studies on antigen-specific BCR of infections, vaccinations, autoimmune diseases and cancer. By analyzing autoantibody sequences of SLE as a case, the identification of autoantigens has become potentially possible due to this characterization.
Receptors, Antigen, B-Cell/metabolism* ; B-Lymphocytes/metabolism* ; Lymphocyte Activation ; High-Throughput Nucleotide Sequencing/methods*

B lymphocyte cell senses and acquires foreign antigens through clonal distributed B cell receptors (BCRs) expressed on the surface of plasma membrane. The presentation formats of antigens are quite diverse. Based on their Brownian diffusion mobility, there are three forms: free mobile soluble antigens, lateral mobile membrane bound antigens, and fixed immobile antigens. Here, using high resolution high speed live cell imaging approaches, we provide evidence that BCR microclusters are formed on the surface of B cells shortly after B cell's encountering of antigens with each format of motion features. Through high speed live cell imaging, we determine that these BCR microclusters show dynamic growth feature and by doing so function as the basic platforms for B cells to acquire the antigens. We propose that the formation and dynamic growth of BCR microcluster is a universal mechanism for B cell to response to antigens with diverse motion features.
Adaptive Immunity ; Animals ; Antigens ; immunology ; metabolism ; B-Lymphocytes ; immunology ; metabolism ; Cell Membrane ; metabolism ; Cells, Cultured ; Humans ; Mice ; Mice, Transgenic ; Microscopy, Fluorescence ; Protein Transport ; immunology ; Receptors, Antigen, B-Cell ; metabolism ; Single-Cell Analysis ; Time-Lapse Imaging

BACKGROUND/AIMS: The protective role of HBV-specific CD8+ cells is dependent on their ability to efficiently migrate to the infected liver, where they may exert an effector function. The migratory behavior of CD8+ cells is influenced by their expression of different chemokine receptors. This study was intended to analyse the pattern of chemokine receptor expression of HBV specific CD 8+ cells in chronic B viral infection. METHODS: We analysed the CCR5 and CCR3 profile of HBV-specific CD8+ cells isolated from the blood and liver of patients with different patterns of HBV infection. Purified T cells were stained directly ex vivo, or after antigen-specific stimulation, using HBV peptide-specific HLA tetramers and monoclonal antibodies to CD8, CCR5 and CCR3, with analysis by flow cytometry. RESULTS: In patients with chronic hepatitis B characterised by low levels of virus (serum HBV DNA <0.5pg/mL) and minimal liver inflammation, analysis of circulating and intrahepatic CD8+ cells demonstrated that liver infiltrating Tc18-27-specific cells were preferentially CCR5+ (up to 80% of HBV-specific CD8+ cells), in contrast to cells of the same specificity within the circulating compartment (up to 35% of HBV-specific CD8+ cells). Furthermore, CCR3 was expressed by about 10% of Tc18-27+ cells infiltrating the liver, but was absent from circulating cells. Following HBV-specific stimulation in vitro the CCR5 expression of circulating Tc18-27-specific cells was up-regulated, to levels found in liver infiltrating cells, whereas CCR3 expression was unchanged. CONCLUSIONS: The chemokine receptor profile of HBV-specific CD8+ cells is influenced by the anatomical site of these cells, and the clinical pattern of disease. The ability of circulating HBV-specific CD8+ cells of patients with low replicating virus to upregulate CCR5 suggests that these cells may respond to increases in virus replication by efficiently migrating into the infected liver.
CD8-Positive T-Lymphocytes/immunology/*metabolism ; English Abstract ; Hepatitis B Virus/immunology ; Hepatitis B, Chronic/*immunology/pathology ; Human ; Liver/pathology ; Receptors, CCR5/metabolism ; Receptors, Chemokine/*metabolism ; T-Cell Antigen Receptor Specificity

<b>OBJECTIVEb>To identify the immunohistochemical patterns of follicular dendritic cell (FDC) meshwork and Ki-67 labeling index in small B-cell lymphomas (SBLs) and their significance in differential diagnosis.

<b>METHODSb>Sixty-eight cases of SBLs were included collected from November 2008 to June 2012. The patterns of FDCs and Ki-67 expression were studied on paraffin sections by CD21, CD23 and Ki-67 immunohistochemistry. The characteristic staining patterns of FDCs and Ki-67 expression among different SBLs were analyzed statistically.

<b>RESULTSb>The age of SBL patients ranged from 28 to 85 years with a mean of 55.2 years. The male to female ratio was 1.2:1. Fifty-five cases involved only lymph nodes (80.9%), and the remaining cases involved multiple extra-nodal sites. Histological classification of the cases was made according to the 2008 WHO lymphoma classification criteria: 22 were low-grade follicular lymphomas (FLs, including grade 1 and grade 2), 19 marginal zone lymphomas (MZLs), 17 mantle cell lymphomas (MCLs), and 10 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLLs). FDC meshwork limited to the central part of neoplastic follicles was characteristic for FL (90.9%, 20/22). The germinal center FDC meshwork was destroyed primarily at periphery in MZL (14/19). The absence or scattered FDC clusters were typical of SLL/ CLL. Irregular FDC was seen in 7/17 of MCL, while 7/17 MCL displayed FDC pattern similar to that of CLL/SLLs. The pattern of FDCs was a significantly diagnostic feature in distinguishing the four types of SBLs (P < 0.01). Ki-67 was also a statistically significant parameter (P < 0.05) with decreasing labeling index as the following: MCL, FL, SLL and MZL. Ki-67 showed scattered pattern in germinal centers with loss of polarity in FLs. MZL presented uniformly scattered positive pattern in interfollicullar areas. Ki-67 staining was uniform in MCL, but its labeling index varied from 5% to 90%. The Ki-67 index was higher in the morphological "proliferation centers" of all CLL/SLLs.

<b>CONCLUSIONb>Immunohistochemical staining patterns of FDC meshworks and Ki-67 labeling index offer a significant discriminatory power in the differential diagnoses among SBLs.

Adult ; Aged ; Aged, 80 and over ; Antigens, CD20 ; metabolism ; Dendritic Cells, Follicular ; pathology ; Diagnosis, Differential ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Leukemia, Lymphocytic, Chronic, B-Cell ; metabolism ; pathology ; Lymphoma, B-Cell ; classification ; metabolism ; pathology ; Lymphoma, B-Cell, Marginal Zone ; metabolism ; pathology ; Lymphoma, Follicular ; metabolism ; pathology ; Lymphoma, Mantle-Cell ; metabolism ; pathology ; Lymphoma, Non-Hodgkin ; metabolism ; pathology ; Male ; Middle Aged ; Receptors, Complement 3d ; metabolism ; Receptors, IgE ; metabolism ; Retrospective Studies

<b>OBJECTIVEb>To investigate the rate of dual rearrangements of lymphocytic antigen receptor genes in non-Hodgkin lymphomas (NHL) and its pathogenesis and pathologic significance.

<b>METHODSb>PCR analysis of monoclonal, polyclonal and dual rearrangements of IgH and TCR gamma, TCR beta genes was carried out in 125 cases of NHL to evaluate the rate of dual rearrangements, immunohistochemistry was performed for a Ki67 protein expression in 117 cases and the proliferation index was calculated. The relationship between antigen receptor gene rearrangements and proliferation index was analyzed.

<b>RESULTSb>Combination of the two pairs of IgH gene primers with the multiplex PCR for TCR gamma and TCR beta gene revealed dual rearrangements in 8% (8/96) of B-NHL, 17% (5/29) of T-NHL. In B cell NHL, IgH gene monoclonal, dural and polyclonal rearrangements were identified in 65, 8 and 15 cases respectively, while in T-cell NHL, they were in 15, 5 and 9 cases, respectively. There was no significant difference between proliferation index and monoclonal, dual, polyclonal rearrangements in both B-NHL and T-NHL by One-way test.

<b>CONCLUSIONb>Dual rearrangements in NHL are not rare and have no relationship with proliferation index.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Carrier Proteins ; genetics ; Cell Proliferation ; Child ; Female ; Gene Rearrangement ; Genes, T-Cell Receptor gamma ; genetics ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Lymphoma, B-Cell ; genetics ; metabolism ; pathology ; Lymphoma, Non-Hodgkin ; genetics ; metabolism ; pathology ; Lymphoma, T-Cell ; genetics ; metabolism ; pathology ; Male ; Middle Aged ; Polymerase Chain Reaction ; Receptors, Antigen ; genetics ; Young Adult

<b>BACKGROUNDb>Sam68 plays an important role as a multiple functional RNA binding nuclear protein in cell cycle progress, RNA usage, signal transduction, and tyrosine phosphorylation by Src during mitosis. However, its precise impact on these essential cellular functions remains unclear. The purpose of this study is to further elucidate Sam68 functions in RNA metabolism, signal transduction regulation of cell growth and cell proliferation in DT40 cell line.

<b>METHODSb>By using gene targeting method, we isolated a mutation form of Sam68 in DT40 cells and described its effect on cell growth process and signal transduction. Southern, Northern, and Western blot, phosphorylation and flow-cytometric analyses were performed to investigate the Sam68 functions.

<b>RESULTSb>A slower growth rate (2.1 hours growth elongation) and longer S phase (1.7 hours elongation) was observed in the Sam68 mutant cells. Serum depletion resulted in increased amounts of dead cells, and expansion of S phase in mutant cells. Upon B cell cross-linking, the maximal level of tyrosine phosphorylation on BLNK was observed to be significantly lower in mutant cells.

<b>CONCLUSIONSb>The proline rich domain of Sam68 is involved in cell growth control by modulating the function of mRNAs in S phase or earlier and the functions as an adaptor molecule in B cell signal transduction pathways.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; physiology ; Animals ; B-Lymphocytes ; cytology ; immunology ; physiology ; Binding Sites ; genetics ; Blotting, Western ; Cell Cycle ; physiology ; Cell Death ; physiology ; Cell Growth Processes ; drug effects ; physiology ; Cell Line, Tumor ; Culture Media, Serum-Free ; pharmacology ; Mutation ; genetics ; Phosphorylation ; Proline ; genetics ; RNA-Binding Proteins ; genetics ; metabolism ; physiology ; Receptors, Antigen, B-Cell ; immunology ; physiology ; Signal Transduction ; drug effects ; physiology ; Tyrosine ; metabolism

<b>OBJECTIVEb>To compare the expression differences of breast cancer resistance protein(BCRP/ABCG2) and P-glycoprotein(P-gp) in breast cancer tissue before chemotherapy and in residual breast cancer tissue, and to explore its correlation with breast cancer stem cells.

<b>METHODSb>Immunohistochemistry was used to detect the expression of ABCG2, P-gp, and breast cancer stem cells(BCSCs) markers(CD44 and CD24) in breast cancer tissue before chemotherapy and residual breast cancer tissue after chemotherapy. Immunofluorescence was applied for determination of the CD44 and CD24 protein expressions of BCSCs microspheres cells. The monoclone-forming ability of BCSCs microspheres cells was detected by limited dilution assay. The expressions of ABCG2, P-gp, CD44, and CD24 proteins were detected by Western blot.

<b>RESULTSb>Compared with those in breast cancer tissue before chemotherapy, the expression levels of ABCG2 and P-gp were positively correlated with the expression level of CD44 protein(Χ(2)=41.34, r=0.83;Χ(2)=22.81, r=0.61) in residual breast cancer tissue after chemotherapy;meanwhile, they were negatively correlated with the expression of CD24 protein(Χ(2)=-21.25, r=0.72;Χ(2)=-17.26, r=0.65) (all P<0.05) .The diameter of BCSCs microspheres were increased significantly after chemotherapy.The content of BCSCs increased by about 2.5 times after chemotherapy.The expressions of ABCG2, P-gp and CD44 proteins significantly increased and that of CD24 protein significantly declined(P<0.05) .

<b>CONCLUSIONb>Chemotherapy endows residual breast cancer tissue with cancer stem cells-like features, leading to multidrug resistance of breast cancer.

ATP Binding Cassette Transporter, Sub-Family B ; ATP Binding Cassette Transporter, Sub-Family G, Member 2 ; ATP-Binding Cassette Transporters ; metabolism ; ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Adult ; Aged ; Breast Neoplasms ; drug therapy ; metabolism ; CD24 Antigen ; metabolism ; Cell Culture Techniques ; Drug Resistance, Neoplasm ; Female ; Humans ; Hyaluronan Receptors ; metabolism ; Middle Aged ; Neoplasm Proteins ; metabolism ; Neoplasm, Residual ; Neoplastic Stem Cells ; cytology ; metabolism

This study aimed at constructing a draft genome of the adult female worm Toxocara canis using next-generation sequencing (NGS) and de novo assembly, as well as to find new genes after annotation using functional genomics tools. Using an NGS machine, we produced DNA read data of T. canis. The de novo assembly of the read data was performed using SOAPdenovo. RNA read data were assembled using Trinity. Structural annotation, homology search, functional annotation, classification of protein domains, and KEGG pathway analysis were carried out. Besides them, recently developed tools such as MAKER, PASA, Evidence Modeler, and Blast2GO were used. The scaffold DNA was obtained, the N50 was 108,950 bp, and the overall length was 341,776,187 bp. The N50 of the transcriptome was 940 bp, and its length was 53,046,952 bp. The GC content of the entire genome was 39.3%. The total number of genes was 20,178, and the total number of protein sequences was 22,358. Of the 22,358 protein sequences, 4,992 were newly observed in T. canis. Following proteins previously unknown were found: E3 ubiquitin-protein ligase cbl-b and antigen T-cell receptor, zeta chain for T-cell and B-cell regulation; endoprotease bli-4 for cuticle metabolism; mucin 12Ea and polymorphic mucin variant C6/1/40r2.1 for mucin production; tropomodulin-family protein and ryanodine receptor calcium release channels for muscle movement. We were able to find new hypothetical polypeptides sequences unique to T. canis, and the findings of this study are capable of serving as a basis for extending our biological understanding of T. canis.
Adult ; B-Lymphocytes ; Base Composition ; Classification ; DNA ; Female ; Genome* ; Genomics ; Humans ; Larva Migrans, Visceral* ; Metabolism ; Mucins ; Peptides ; Protein Structure, Tertiary ; Receptors, Antigen, T-Cell ; RNA ; Ryanodine Receptor Calcium Release Channel ; T-Lymphocytes ; Toxocara canis* ; Toxocara* ; Transcriptome ; Ubiquitin-Protein Ligases

<b>OBJECTIVEb>To establish an accurate and efficient method for detecting recent thymic output function and analyze the content of T-cell receptor (TCR) rearrangement excision circles (TRECs) within peripheral blood mononuclear cells (PBMCs).

<b>METHODSb>According to the specific sequence of TCRdelta, the primers and the fluorescent probe (TaqMan) were designed and synthesized. The standard quantitative template was constructed by T/A cloning. The method for detecting TRECs was established after optimization of reaction condition, then its specificity, sensitivity and stability were tested. Quantitative detection of TRECs in DNA of PBMCs from normal individuals and patients of chronic hepatitis B were preformed by real-time PCR using TaqMan technique.

<b>RESULTSb>Detection of TRECs was quick and accurate by real-time fluorescence quantitative PCR. The CV value of Ct was 1.06%, the product was specific which was confirmed by electrophoresis and sequencing and the method showed high sensitivity. The mean value of TRECs from normal individuals was (7767.4 +/- 2369.5) copies/10(6)PBMCs in healthy controls at age 21.45 but (28,374.4 +/- 7820.4) copies/10(6)PBMCs in those at age 16.20 (P < 0.05). The mean value of TRECs from patients with chronic hepatitis B was (6480.9 +/- 2031.2) copies/10(6) PBMCs in those at age 21.45, which was statistically significant as compared with normal individuals at age 21.45.

<b>CONCLUSIONb>Real-time fluorescence quantitative PCR for detecting the TRECs is an accurate, efficient and stable method and the recent thymic output function might decrease in patients with chronic hepatitis B.

Adult ; DNA Primers ; Female ; Gene Rearrangement, T-Lymphocyte ; Hepatitis B, Chronic ; blood ; genetics ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; methods ; Receptors, Antigen, T-Cell, gamma-delta ; genetics ; Reproducibility of Results ; Thymus Gland ; immunology ; metabolism ; Young Adult

Hematopoietic neoplasm coexpressing CD4 and CD56 includes a subset of acute myeloid leukemia with myelomonocytic differentiation, plasmacytoid monocyte tumor, and other immature hematopoietic neoplasms of undefined origin. Herein, we report a CD4+CD56+CD68+ hematopoietic tumor that was thought to be a tumor of plasmacytoid monocytes. This case is unique in the absence of accompanying myelomonocytic leukemia and the faint expression of cCD3 on the tumor cells. The patient was a 22-yr old man presented with multiple lymphadenopathy and an involvement of the bone marrow. Tumor cells were large and monomorphic with an angulated eosinophilic cytoplasm of moderate amount. Nuclei of most tumor cells were eccentric and round with one or two prominent nucleoli. Rough endoplasmic reticulum was prominent in electron microscopic examination. Tumor cells expressed CD4, CD7, CD10, CD45RB, CD56, CD68, and HLA-DR and were negative for CD1a, CD2, sCD3, CD5, CD13, CD14, CD20, CD33, CD34, CD43, CD45RA, TIA-1, S-100, and TdT. cCD3 was not detected in the immunostaining using paraffin tissue, but was faintly expressed in flow cytometry and immunostaining using a touch imprint slide. T-cell receptor gene rearrangement analysis and EBV in situ hybridization showed negative results. Cytochemically, myeloperoxidase, Sudan black B, and alpha naphthyl butyrate esterase were all negative.
Adult ; Antigens, CD/*biosynthesis ; Antigens, CD3/*biosynthesis ; Antigens, CD4/*biosynthesis ; Antigens, CD45/biosynthesis ; Antigens, CD56/*biosynthesis ; Antigens, Differentiation, Myelomonocytic/*biosynthesis ; Bone Marrow Cells/pathology ; Cell Nucleus/pathology ; Eosinophils/metabolism ; Flow Cytometry ; Gene Rearrangement ; Humans ; Immunohistochemistry ; In Situ Hybridization ; Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis/*metabolism ; Lymph Nodes/pathology ; Male ; Microscopy, Electron ; Monocytes/*metabolism ; Receptors, Antigen, T-Cell/metabolism