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 study the association between hepatitis B virus (HBV) mutants and the pathogenesis of severe hepatitis B by full-length HBV genome.

<b>METHODSb>Serum samples from 10 severe hepatitis B patients were collected in our hospital. Serum HBV DNAs were extracted using DNA mini Kit, and amplified by LA Taq DNA polymerase to yield full-length HBV DNA. PCR products were isolated and cloned into vector pUCm-T, then transfected into DH-5 alpha cells. Positive clones were selected and checked by digestion, and full-length HBV DNAs were sequenced.

<b>RESULTSb>4 cases were cloned into vector pUCm-T successfully and completed the full-length sequencing. Among them, 3 cases had a G to A mutation at nucleotide 1896 in pre-C region and 1 had a double mutation of T1762-A1764 in the core promoter region. Some amino acid changes occurred within the known CTL, B or T cell epitopes of the PrS2 and C regions.

<b>CONCLUSIONSb>This method could serve to study the relationship between HBV genome and the pathogenesis of severe hepatitis B.

Adult ; B-Lymphocytes ; metabolism ; Cloning, Molecular ; Epitopes ; genetics ; Genome, Viral ; genetics ; Hepatitis B ; etiology ; virology ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B virus ; genetics ; Humans ; Male ; Middle Aged ; Mutation ; Protein Precursors ; genetics ; Sequence Analysis ; T-Lymphocytes, Cytotoxic ; metabolism

The aim of this study is to investigate the effect of hyperin on the cccDNA of duck hepatitis B virus and its immunological regulation. Duck hepatitis B virus (DHBV) infection model and normal mouse spleen lymphocyte were used to evaluate the anti-HBV and immunoregulation effects. The DHBV-DNA of serum was detected at different time points by using serum DOT-BLOT hybridization. Polymerase chain reaction (PCR) was used for the determination of nuclear covalent closed circular DNA (cccDNA). Cytokine secretion was determined by ELISA method. DHBV-DNA were inhibited by hyperin (25 or 50 mg x kg(-1)), while cccDNA of liver could be eliminated efficiently by hyperin (25 or 50 mg x kg(-1), P < 0.05, P < 0.01). The T helper 1 effector cytokine was markedly enhanced by hyperin (25 or 50 microg x mL(-1), P < 0.01). In conclusion, hyperin has anti-HBV activity via multiple targets and pathways, and cccDNA may be one of the important targets.
Animals ; Antiviral Agents ; pharmacology ; DNA, Circular ; metabolism ; DNA, Viral ; metabolism ; Hepadnaviridae Infections ; virology ; Hepatitis B Virus, Duck ; genetics ; Hepatitis, Viral, Animal ; virology ; Interferon-gamma ; secretion ; Interleukin-12 ; secretion ; Liver ; virology ; Lymphocytes ; secretion ; Mice ; Quercetin ; analogs & derivatives ; pharmacology ; Spleen ; pathology ; virology

We report the case of a patient who presented with cystic lymphoid hyperplasia of the right parotid gland as the index diagnosis of HIV infection. Histological examination of the excised parotid gland revealed a solid-cystic lymphoepithelial lesion with a non-keratinous squamous epithelium, which grew into the lymphoid component via anastomosing cords and islands. These anastomosing cords and islands contained variably abundant B cells, several subepithelial multinucleated histiocytes, salivary ducts infiltrated by small lymphocytes, and a dense lymphoid infiltrate containing lymphoid follicles with enlarged, irregular germinal centres.
Adult ; B-Lymphocytes ; cytology ; Biopsy ; Epithelial Cells ; cytology ; Epithelium ; metabolism ; HIV Infections ; diagnosis ; Humans ; Hyperplasia ; pathology ; virology ; Immunohistochemistry ; Lymphocytes ; cytology ; Male ; Parotid Gland ; pathology ; virology ; Salivary Glands ; pathology ; Tomography, X-Ray Computed

Human T cell leukemia virus type 1 (HTLV-1), an etiological factor that causes adult T cell leukemia and lymphoma (ATL), infects over 20 million people worldwide. About 1 million of HTLV-1-infected patients develop ATL, a highly aggressive non-Hodgkin's lymphoma without an effective therapy. The pX region of the HTLV-1 viral genome encodes an oncogenic protein, Tax, which plays a central role in transforming CD4+ T lymphocytes by deregulating oncogenic signaling pathways and promoting cell cycle progression. Expression of Tax following viral entry is critical for promoting survival and proliferation of human T cells and is required for initiation of oncogenesis. Tax exhibits diverse functions in host cells, and this oncoprotein primarily targets IκB kinase complex in the cytoplasm, resulting in persistent activation of NF-κB and upregulation of its responsive gene expressions that are crucial for T cell survival and cell cycle progression. We here review recent advances for the pathological roles of Tax in modulating IκB kinase activity. We also discuss our recent observation that Tax connects the IκB kinase complex to autophagy pathways. Understanding Tax-mediated pathogenesis will provide insights into development of new therapeutics in controlling HTLV-1-associated diseases.
Autophagy ; CD4-Positive T-Lymphocytes ; metabolism ; virology ; Cell Cycle ; Cell Transformation, Neoplastic ; genetics ; Gene Expression Regulation, Neoplastic ; Gene Products, tax ; genetics ; metabolism ; Human T-lymphotropic virus 1 ; physiology ; Humans ; I-kappa B Kinase ; genetics ; metabolism ; Leukemia-Lymphoma, Adult T-Cell ; genetics ; metabolism ; virology ; Membrane Microdomains ; metabolism ; virology ; NF-kappa B ; genetics ; metabolism ; Protein Binding ; Signal Transduction ; genetics

<b>OBJECTIVEb>To establish immortalized B-lymphoblastoid cell lines of keloid pedigree transformed with Epstein-Barr (EB) virus and conduct karyotype analysis of the cells.

<b>METHODSb>Immortalized B-lymphoblastoid cell lines were established by EB virus transformation of the peripheral blood B lymphocytes from the members of keloid pedigree. Karyotype analysis was performed for the cultured cells of passages 10, 20, 30, and 35 to evaluate their genetic stability.

<b>RESULTSb>Altogether 27 immortalized lymphoblastoid cell lines with stable chromosome were obtained successfully from the keloid pedigree. No chromosomal abnormalities were found in the cultured cells until passages 30 and 35, in which variation in chromosome number and structure are detected.

<b>CONCLUSIONb>The cell lines of the keloid pedigree established in this study can be useful in future studies, and genetic analysis is conducted preferably with cells of early passages.

B-Lymphocytes ; cytology ; metabolism ; virology ; Cell Line, Transformed ; Cell Lineage ; Cell Transformation, Viral ; Female ; Herpesvirus 4, Human ; physiology ; Humans ; Karyotyping ; Keloid ; genetics ; pathology ; Male

Interferon regulatory factor 7 (IRF7) is one of the transcriptional factors for the activation of type I Interferon (IFN) genes. It is known that IRF7 and the latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) are highly expressed in EBV type III latency cells, and LMP1 induces mRNA expression of IRF7. In this study, the expression pattern of endogenous IRF7 was observed in several B cell lines with or without EBV infection by immunofluorescence staining. IRF7 was localized in the cytoplasm of EBV-negative B cells and EBV type I latency B cell lines. However, IRF7 was located both in the cytoplasm and nucleus of EBV type III latency cell lines. In the Jijoye cell (type III latency cell), IRF7 was colocalized with LMP1 in the cytoplasm in a capping configuration, and their interaction was confirmed by co-immunoprecipitation of LMP1 and IRF7. This colocalization was confirmed by co-transfection of IRF7 and LMP1 plasmids in EBV-negative B cells. These results suggest that the IRF7 and LMP1 interact with each other, and this may relate to the mechanism whereby LMP1 exerts functional effects in B-lymphocytes.
Viral Matrix Proteins/*biosynthesis/metabolism ; Trans-Activation (Genetics) ; Signal Transduction ; RNA, Messenger/metabolism ; Plasmids/metabolism ; Microscopy, Fluorescence ; Interferon Regulatory Factor-7/*biosynthesis ; Immunoprecipitation ; Humans ; Herpesvirus 4, Human/metabolism ; *Gene Expression Regulation ; Cytoplasm/metabolism ; Cell Line, Tumor ; B-Lymphocytes/metabolism/virology

To screen the interactive proteins with IBDV Gt VP2 protein from cDNA library of B Lymphoid cells of the bursa of Fabricius. The expression cDNA library plasmids was transformed to the yeast competent cells, which have the bait plasmid-Gt VP2. After testing for growth in synthetic complete medium lacking histidine and uracil and for production of beta-galactosidase (X-gal), we obtained 16 positive clones. We searched the gene sequences of positive clones in the NCBI website. The blast results showed that five positive clones were the gallus sequences. They were Gallus gallus breed mitochondrial DNA, O_G1cNAc transferase, Tumor protein p53 binding protein, Stathmin and Chondroitin sulfate Ga1NAcT-2, respectively. This study is helpful for the further identifying the receptors of IBDV in B Lymphoid cells of the bursa of Fabricius.
Animals ; B-Lymphocytes ; metabolism ; virology ; Bursa of Fabricius ; metabolism ; Chickens ; DNA, Mitochondrial ; metabolism ; Gene Library ; Infectious bursal disease virus ; Protein Binding ; Protein Interaction Mapping ; Receptors, Virus ; metabolism ; Tumor Suppressor Protein p53 ; metabolism ; Two-Hybrid System Techniques ; Viral Structural Proteins ; genetics ; metabolism

Adult ; Alanine Transaminase ; blood ; CD4-Positive T-Lymphocytes ; immunology ; metabolism ; CD8-Positive T-Lymphocytes ; immunology ; metabolism ; Carrier State ; immunology ; virology ; DNA, Viral ; blood ; Female ; Flow Cytometry ; Hepatitis B ; immunology ; virology ; Hepatitis B virus ; immunology ; Humans ; Immunologic Memory ; Interleukin-7 Receptor alpha Subunit ; immunology ; metabolism ; Male

Immune-mediated inflammatory injury is an important feature of the disease aggravation of hepatitis B virus-related acute-on-chronic liver failure (ACLF). Toll-like receptors (TLRs) have been shown previously to play a pivotal role in the activation of innate immunity. The purpose of this study was to characterize the TLR4 expression in peripheral blood mononuclear cells (PBMCs) of ACLF patients and its possible role in the disease aggravation. Twelve healthy subjects, 15 chronic HBV-infected (CHB) patients and 15 ACLF patients were enrolled in this study. The TLR4 expression in PBMCs and T cells of all subjects was examined by real-time PCR and flow cytometry. The correlation of TLR4 expression on T cells with the markers of disease aggravation was evaluated in ACLF patients. The ability of TLR4 ligands stimulation to induce inflammatory cytokine production in ACLF patients was analyzed by flow cytometry. The results showed that TLR4 mRNA level was upregulated in PBMCs of ACLF patients compared to that in the healthy subjects and the CHB patients. Specifically, the expression of TLR4 on CD4(+) and CD8(+) T cells of PBMCs was significantly increased in ACLF patients. The TLR4 levels on CD4(+) and CD8(+) T cells were positively correlated with serum total bilirubin (TBIL), direct bilirubin (DBIL), international normalized ratio (INR) levels and white blood cells (WBCs), and negatively correlated with serum albumin (ALB) levels in the HBV-infected patients, indicating TLR4 pathway may play a role in the disease aggravation of ACLF. In vitro TLR4 ligand stimulation on PBMCs of ACLF patients induced a strong TNF-α production by CD4(+) T cells, which was also positively correlated with the serum markers for liver injury severity. It was concluded that TLR4 expression is upregulated on T cells in PBMCs, which is associated with the aggravation of ACLF.
Adult ; End Stage Liver Disease ; metabolism ; virology ; Female ; Hepatitis B virus ; pathogenicity ; Humans ; Male ; Middle Aged ; Monocytes ; metabolism ; RNA, Messenger ; genetics ; T-Lymphocytes ; metabolism ; Toll-Like Receptor 4 ; genetics ; metabolism ; Up-Regulation