Hepatitis B virus ; Hepatitis B, Chronic ; immunology ; virology ; Humans ; T-Lymphocytes ; immunology

Progressive multifocal leukoencephalopathy (PML) is a rare and lethal central nervous demyelinating disease caused by JC polyomavirus (JCV), particularly in patients with impaired immune system. The variation of JCV plays an important role in the pathogenesis of PML, including the recombination of non-coding regulatory region (NCCR), which is closely related to binding sites of transcription factors and affect the level of gene transcription. Nucleotide mutations in VP1 region determine the antigenicity and receptor specificity of JCV, play an important role in cell adsorption, immune-mediation and pathogenicity. In addition, immune cells are also involved in the pathogenesis of PML. T lymphocytes can recognize virus antigens, clear JCV, which are directly related to the prognosis of PML. B lymphocytes can serve as latent sites of JCV, and participate in viral transmission, replication, and coordination of the expression of transcription factors. This paper summarizes the roles of JCV variation and immune cells in pathogenesis of PML.
B-Lymphocytes ; immunology ; virology ; Capsid Proteins ; genetics ; immunology ; Humans ; JC Virus ; immunology ; Leukoencephalopathy, Progressive Multifocal ; pathology ; virology ; Mutation ; T-Lymphocytes ; immunology ; virology

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

This study was aimed to explore the method for induction and expansion of EB virus specific cytotoxic T lymphocytes (EBV-CTL) in vitro, and to detect their killing effect. Peripheral blood mononuclear cells (PBMNC) were collected from 6 EBV seropositive healthy donors, and EBV-transformed B lymphoblastoid cells (BLCL)were used as the antigen-presenting cells and antigen stimulant which was irradiated by 40 Gy (60)Co irradiator. The autologous PBMNC and irradiated BLCL were cultured to induce and expand the EBV-CTL, and the immunophenotype was identified by the flow cytometry. The killing effect of the EBV-CTL against the autologous BLCL (autoBLCL), the autologous PHA cultured B lymphoblastoid cells( PHA-BLCL), the allogeneic BLCL (alloBLCL) and the K562 cells were measured with LDH release assay under different effector-to-target ratio. The results showed that the 6 cell lines of EBV-CTL were induced and expanded from the EBV seropositive healthy donors, the overall increase in cell numbers varied from 18.6 to 55.0 times. After 10 stimulations, the specific killing efficiency of the EBV-CTL for the autoBLCL were 59.4%, 43.2% and 29.0% under the effector-to-target ratio of 20: 1, 10: 1 and 5: 1. The nonspecific killing efficiency for the PHA-blast, alloBLCL and K562 cells were 7.1%, 9.4% and 10.3% (P < 0.05) under the 20: 1 ratio; 6.6%, 8.3% and 8.1% (P < 0.05) under 10: 1; 5.4%, 7.3% and 6.3% (P < 0.05) under 5: 1, respectively. It is concluded that the EBV-CTL can be successfully induced and expanded ex vivo for specific killing of HLA matched BLCL and may become a potential treatment for EBV related post-transplant lymphoproliferative disorders.
B-Lymphocytes ; immunology ; Cell Line, Transformed ; Herpesvirus 4, Human ; immunology ; Humans ; K562 Cells ; Leukocytes, Mononuclear ; immunology ; virology ; T-Lymphocytes, Cytotoxic ; cytology ; immunology ; virology

<b>OBJECTIVEb>To explore whether hepatitis B virus (HBV) S gene-modified dendritic cells (DCs) might induce a specific cytotoxic T lymphocyte (CTL) response.

<b>METHODSb>The recombinant adenoviruses carrying HBsAg genes were prepared and used to transfect DCs generated from cord blood. The efficacy of transfection was observed through the expression of enhanced green fluorescent protein (EGFP) in DCs and the expression of HBsAg was detected by ELISA. HBV S gene-modified DCs were co-cultured with T cells from cord blood and T cells stimulating activities were detected using mixed lymphocyte reaction (MLR). The CTL assay was carried out to assess the ability of CTL lines to lyse target cells of HepG(2)22.1.5 by measuring lactate dehydrogenase (LDH) release.

<b>RESULTSb>The results showed that HBV S genes were expressed in DCs with high efficacy by recombinant adenoviral vector. DCs had a normal shape after transfection. The result of MLR showed that HBV S gene-modified DCs could effectively stimulate naive T cells to proliferate. The induced specific CTL lines could lyse target cells of HepG(2)22.1.5.

<b>CONCLUSIONSb>HBV S gene-modified DCs enhanced the function to induce a specific CTL effect, showing its promise for developing anti-viral vaccine in future.

Cell Line ; Cells, Cultured ; Cytotoxicity, Immunologic ; Dendritic Cells ; immunology ; virology ; Hepatitis B ; immunology ; virology ; Hepatitis B Surface Antigens ; genetics ; immunology ; Hepatitis B virus ; genetics ; immunology ; Humans ; Lymphocyte Culture Test, Mixed ; T-Lymphocytes, Cytotoxic ; immunology

<b>OBJECTIVEb>To establish a method for efficient induction and expansion of Epstein Barr virus (EBV)-specific cytotoxic T lymphocytes (CTL) in vitro and evaluate the possibility of using this strategy for treatment of nasopharyngeal carcinoma (NPC).

<b>METHODSb>EBV-transformed B lymphoblastoid cells (BLCLs) were used as the antigen stimuli and antigen-presenting cells. EBV-specific CTL was induced by co-culture of the autologous peripheral blood mononuclear cells (PBMCs) and the irradiated BLCLs, and expanded with a cocktail method consisting of OKT-3, irradiated homologous PBMC, and IL-2. The specific activity of the CTL against the NPC cells was measured with MTT assay.

<b>RESULTSb>EBV-specific CTL was successfully induced and expanded by 600 folds. The killing efficiency of the CTL was 76% for autologous BLCLs, 13% for homologous BLCLs, 51% for autologous NPC cells, and 27% for homologous CNE cell line, and after expansion, the corresponding killing efficiencies were 63%, 25%, 49%, and 33%, respectively. The non-specific killing only slightly increased after the expansion.

<b>CONCLUSIONb>EBV-specific CTL can be successfully induced and expanded in vitro for specific killing of autologous NPC cells, suggesting the potential of this strategy in the treatment of NPC.

Antigen-Presenting Cells ; cytology ; immunology ; Antigens, Viral ; immunology ; B-Lymphocytes ; cytology ; immunology ; virology ; Cells, Cultured ; Coculture Techniques ; Herpesvirus 4, Human ; immunology ; Humans ; Immunotherapy, Adoptive ; Nasopharyngeal Neoplasms ; immunology ; pathology ; therapy ; T-Lymphocytes, Cytotoxic ; cytology ; immunology ; virology ; Tumor Cells, Cultured

BACKGROUNDS/AIMS: Hepatitis B virus(HBV) specific cytotoxic T lymphocyte (CTL) response is believed to play a major role in virus control and liver damage in chronic hepatitis B(CHB). We performed this study to evaluate whether HBV specific CTL could be visualized directly by tetrameric HLA-A2/core 18-27 complex(T c18-27) in the peripheral blood and liver of patients with CHB. On the basis of our results we clarified patients intrahepatic compartmentalization and correlation with HBV specific CTL and viral replication or liver damage. METHODS: We stained peripheral blood mononuclear cells of 33 HLA-A2 + and 8 HLA-A2 patients with CHB with cychrome conjugated anti-CD8 mAb and phycoerythrin conjugated T c18-27. Among these we analysed intrahepatic lymphocyte of 11 HLA-A2 + patients. We compared the frequency of T c18-27 specific CD8+ cells with serum HBV-DNA levels or alanine aminotransferase(ALT) levels. RESULTS: The frequency of circulating T c18-27 specific CD8+ cell was higher(9-101 cells per 50,000 CD8+ cells) than background level in 14 among 33 patients. The frequency of intrahepatic T c18-27 specific CD8+ cells was 12-2100 cells per 50,000 CD8+ cells in 8 out of 11 patients whose liver was obtained This was 17.4-150 times higher than circulating T c18-27 specific CD8+ cells. The frequency of circulating T c18-27 specific CD8+ cells was increased in 10 out of 18 patients with serum HBV DNA level <0.5 pg/mL and ALT < 40 IU/L. It was increased in just 4 out of 15 patients with HBV DNA level > 800 pg/mL and ALT >70 IU/L. The frequency of intrahepatic T c18-27 CTL tended to be lower in high levels of serum HBV DNA and was not correlated with liver inflammation. CONCLUSION: This study provess that if HBV-specific CTLs are barely detectable in the peripheral blood of CHB, much more HBV-specific CTLs are in the liver and most HBV-specific CTLs are infiltrated in the liver. Also, in the presence of an effective HBV specific CD8 response the inhibition of viral replication can be independent of liver damage.
CD8-Positive T-Lymphocytes/immunology ; DNA, Viral/analysis ; English Abstract ; HLA-A2 Antigen/analysis/*immunology ; Hepatitis B Virus/genetics/*immunology ; Hepatitis B, Chronic/*immunology/virology ; Human ; T-Lymphocytes, Cytotoxic/*immunology ; Viral Core Proteins/*immunology

<b>OBJECTIVEb>To explore the role played by HBV antigen specific cytotoxic lymphocytes (CTLs) in severe hepatitis B patients.

<b>METHODSb>Three kinds of HBV specific CD8+ T cells responding to HBV core 18-27, polymerase 575-583 and envelope 335-343 specific CD8+ T cells were searched with major histocompatibility complex (MHC)-peptide tetramer flow cytometry in the patients we studied. The cytokines produced by these specific CTLs such as IFNgamma, TNFalpha, IL-4, IL-10 were detected using ELISPOT assays. Their ability to lyse target cells was analyzed using a CytoTox96 Non-Radioactive Cytotoxicity Assay kit (Promega).

<b>RESULTSb>The number of HBV core 18-27 specific CD8+ T cells was significantly higher in the peripheral blood of acute severe hepatitis B group patients than that in chronic severe hepatitis group (P less than 0.05), but lower than that in the acute hepatitis B patients. The IFNgamma and TNFalpha levels of acute severe hepatitis B patients were both significantly higher than those in the chronic severe hepatitis group (P less than 0.05). The ability to lyse target cells of HBV core 18-27 CTLs was also significantly higher in the acute severe hepatitis B group than that in the chronic severe hepatitis B group (P less than 0.05).

<b>CONCLUSIONb>The response to antigen stimulation was much higher in acute severe hepatitis B than in chronic severe hepatitis B patients. The specific CTLs persisted among the peripheral blood mononuclear cells in acute severe hepatitis B, which may be related to the viral clearance.

Adolescent ; Adult ; Aged ; Female ; Flow Cytometry ; Hepatitis B ; immunology ; virology ; Hepatitis B virus ; immunology ; Humans ; Male ; Middle Aged ; T-Lymphocytes, Cytotoxic ; immunology ; Young Adult

<b>OBJECTIVEb>To investigate the effect of HBV antigens and pathological mechanism of chronic HBV infection by analyzing the cellular immune function of peripheral blood mononuclear cells (PBMCs) from HBsAg carriers.

<b>METHODSb>PBMCs were prepared from individuals with chronic asymptomatic HBV infection and cultured in the presence of different antigens and/ or cytokines. The levels of cytokines in culture supernatants were detected by ELISA method. The phenotype of the cells was detected by FACS.

<b>RESULTSb>The levels of IFN y secreted by PBMCs from HBsAg carriers were (48.3+/-19.8) pg/ml, significantly lower than that from healthy controls (t = 3.023, P less than 0.05); The IFN y produced by PBMCs from HBeAg positive patients due to HBsAg and HBcAg stimulation were (50.4+/-51.6) pg/ml and (63.2+/-36.9) pg/ml, significantly lower than that of HBeAg negative patients (t = 2.468 and 3.184, P less than 0.05, respectively). The IL-12p70 secreted by PBMCs from HBeAg positive patients was also significantly lower than that of HBeAg negative patients (P less than 0.05); Exogenous IL-12 promoted significantly PBMCs to secrete IFN y (P less than 0.01) and IL-12 combined with HBV antigens activated CD8+CD45RA+CCR7+ and CD8+CD45RA-CD62L+ cells. IL-12 secreted by PBMCs decreased in HBeAg positive patients, which may be the crucial reason of viral persistence in chronic HBV carriers. Exogenous IL-12 combined with specific HBV antigen could promote the central memory CD8+ T cells to produce IFN y.

Adolescent ; Adult ; Carrier State ; blood ; immunology ; virology ; Case-Control Studies ; Hepatitis B ; blood ; immunology ; Hepatitis B Antigens ; blood ; Hepatitis B virus ; immunology ; Humans ; Interferon-gamma ; blood ; Interleukin-12 ; blood ; immunology ; Leukocytes, Mononuclear ; immunology ; T-Lymphocytes ; immunology ; Young Adult

<b>OBJECTIVEb>To study the clinicopathologic features of intravascular large B-cell lymphoma (IVLBCL).

<b>METHODSb>Two autopsy cases of IVLBCL were retrieved from the archival file. The clinicopathologic features, immunohistochemistry and molecular findings were studied.

<b>RESULTSb>The deceased were 70-year-old and 50-year-old males. Both of them had complained of a sudden onset of weakness and numbness of lower extremities. The clinical course deteriorated rapidly, with multi-organ failure. They died 85 days and 44 days after the presentation, respectively. Post-mortem examination did not reveal any mass lesion, except the presence of multiple skin and epicardium nodules, ranging from 0.5 cm to 2.5 cm in diameter, in the first patient. Pericardial effusion, ascites and pleural effusion were also observed. Histologically, neoplastic lymphoid cells filled up the small vessel lumina in many organs, including brain, hypophysis, spinal cord, spinal nerve roots, heart, lungs, kidneys, liver, spleen, digestive tract, pancreas, adrenal, thyroid, testes and lymph nodes. The tumor cells were relatively monotonous and of medium to large in size with round vesicular nuclei and 1 to 3 small basophilic nucleoli. Immunohistochemical study showed that the lymphoma cells expressed B-cell markers CD20 and CD79a, occasionally positive for CD5 and bcl-2 but negative for CD3, bcl-6, CD10, CD30, myeloperoxidase and cytokeratin. In-situ hybridization for Epstein-Barr virus-encoded RNA was negative. The proliferative index, as demonstrated by Ki-67 staining, was about 80%. Molecular study showed the presence of immunoglobulin heavy chain gene rearrangement in both cases, T-cell receptor-gamma gene rearrangement was not found.

<b>CONCLUSIONSb>IVLBCL may present as neurological disturbance and carries distinctive morphologic characteristics, immunophenotype and molecular findings. The prognosis of this disease is often dismal.

Aged ; Antigens, CD20 ; analysis ; Autopsy ; B-Lymphocytes ; pathology ; virology ; CD79 Antigens ; analysis ; Herpesvirus 4, Human ; isolation & purification ; Humans ; Immunohistochemistry ; Lymphoma, B-Cell ; immunology ; pathology ; virology ; Lymphoma, Large B-Cell, Diffuse ; immunology ; pathology ; virology ; Male