EVIHVR: A platform for analysis of expression, variation and identification of human virus receptors

Motivation:Virus receptors are presented on the cell surfaces of a host and are key for viral infection of host cells.However,no unified resource for the study of viral receptors is currently available.Results:To address this problem,we built EVIHVR,a platform for analyzing the expression and variation,and for the identification of human virus receptors.EVIHVR provides three functions:(1)Receptor expression function for browsing and analyzing the expression of human virus receptors in various human tissues/cells;(2)Receptor gene polymorphism function for analyzing the genetic polymorphism of human virus receptors in different human populations and human tissues;and(3)Predict receptor function for identifying potential virus receptors based on differential expression analysis.EVIHVR can become a useful tool for the analysis and identification of human virus receptors.

Expression of Coxsackievirus and Adenovirus Receptor in Human Lung Cancer： Possible Clinical Significance

OBJECTIVE To explore the relationship between CAR and the development of human lung cancer, as well as to provide the basis for the clinical treatment of lung cancer using an adenovirus vector-based gene therapy. METHODS CAR expression was assessed immunohisto- chemically in tumoral, paraneoplastic and normal samples from 112 lung cancer patients. At the same time, the mRNA and protein expression of CAR in 32 cases were determined by RT-PCR and Western blot. The relationship between CAR expression and clinicopathologic parameters was statistically analyzed. RESULTS There was no expression of CAR in normal lung tissue but a little in paraneoplastic tissue. The positive rate was 43% in squamous cell carcinoma, and 70% in adenocarcinoma. Both were much significantly higher than that in paraneoplastic tissue. The CAR expression level in adenocarcinoma was higher than that in squamous cell cancer, mRNA expression by RT-PCR and protein expression by Western blot were consistent with immunohistochemistry results. CONCLUSION CAR is overexpressed in human lung cancer, especially in adenocarcinoma. This data offer the reliable basis for adenovirus-mediated gene therapy of lung cancer; more important, CAR may take part in the formation or development of lung cancer; this may be exploitable for the development of antibody-directed therapy in human lung cancer.

Tim-3 promotes cell aggressiveness and paclitaxel resistance through NF-κB/STAT3 signalling pathway in breast cancer cells

Objective:Although T-cell immunoglobulin and mucin-domain containing molecule-3(Tim-3)has been recognized as a promising target for cancer immunotherapy,its exact role in breast cancer has not been fully elucidated.Methods:Tim-3 gene expression in breast cancer and its prognostic significance were analyzed.Associated mechanisms were then explored in vitro by establishing Tim-3-overexpressing breast cancer cells.Results:In a pooled analysis of The Cancer Genome Atlas(TCGA)database,Tim-3 gene expression levels were significantly higher(P<0.001)in breast cancer tissue,compared with normal tissues.Tim-3 was a prognosis indicator in breast cancer patients[relapse-free survival(RFS),P=0.004;overall survival(OS),P=0.099].Tim-3 overexpression in Tim-3 low breast cancer cells promoted aggressiveness of breast cancer cells,as evidenced by enhanced proliferation,migration,invasion,tight junction deterioration and tumor-associated tubal formation.Tim-3 also enhanced cellular resistance to paclitaxel.Furthermore,Tim-3 exerted its function by activating the NF-κB/STAT3 signalling pathway and by regulating gene expression[cyclin D1(CCND1),C-Myc,matrix metalloproteinase-1(MMP1),TWIST,vascular endothelial growth factor(VEGF)upregulation,concomitant with Ecadherin downregulation).Lastly,Tim-3 downregulated tight junction-associated molecules zona occludens(ZO)-2,ZO-1 and occludin,which may further facilitate tumor progression.Conclusions:Tim-3 plays an oncogenic role in breast cancer and may represent a potential target for antitumor therapy.

DC-SIGN: binding receptors for hepatitis C virus

Objective To review the recent developments in and research into binding receptors of hepatitis C virus (HCV) and especially the role of dendritic cell-specitic adhesion receptor (DC-SIGN) in HCV.Data sources Both Chinese- and English-languge literature was searched using MEDLINE (2000-2003) and the databank of Chinese-language literature (2000-2003).Study selection Relevant articles on DC-SIGN and HCV binding receptors in recent domestic and foreign literature were selected.Data extraction Data were mainly extracted from 40 articles which are listed in the references section of this review. Results DC-SIGN, a dendritic cell-specific adhesion receptor and a type Ⅱ transmembrane mannose-binding C-type lectin, is very important in the function of dendritic cells (DC), both in mediating nave T cell interactions through ICAM-3 and as a rolling receptor that mediates the DC-specific ICAM-2-dependent migration processes. It can be used by HCV and other viral and bacterial pathogens including human immunodeficiency virus (HIV), Ebola virus, CMV and Mycobacterium tuberculosis to facilitate infection. Both DC-SIGN and DC-SIGNR can act either in cis, by concentrating virus on target cells, or in trans, by transmission of bound virus to a target cell expressing appropriate entry receptors. Recent report showed that DC-SIGN not only plays a role in entry into DC, HCV E2 interaction with DC-SIGN might also be detrimental to the interaction of DC with T cells during antigen presentation. Conclusions DC-SIGNs are high-affinity binding receptors for HCV.The clinical strategies that target DC-SIGN may be successful in restricting HCV dissemination and pathogenesis as well as directing the migration of DCs to manipulate appropriate immune responses in autoimmunity and tumorigenic situations.

Crosslinking-mediated activation of the FcεRI:Does it need antigen for success?

Mast cells(MCs),hematopoietic cells of the myeloid lineage,are well-known for their pro-inflammatory nature contributing to the development of various allergic and autoimmune diseases.One of the characteristic receptors on MCs,the high-affinity receptor for IgE(FcεRI),is activated in its IgE-bound state via binding and crosslinking by polyvalent antigen.This results in its phosphorylation by the SRC family kinase LYN,initiating differential signaling pathways,eventually triggering immunological effector functions,such as degranulation and cytokine production.Few publications have reported on FcεRI-dependent but antigen-independent MC activation by antibody-mediated crosslinking of membrane molecules(e.g.,transmembrane proteins and glycosphingolipids)that are both localized in membrane rafts and in close vicinity to the FcεRI.In this Viewpoint we will briefly introduce FcεRI-mediated MC stimulation,cite examples of FcεRI-proximal molecules,the crosslinking of which can cause FcεRI-dependent MC activation,and discuss the potential of certain viruses as well as auto-antibodies to act as indirect FcεRI-crosslinking agents.In latter cases,antigen-independent FcεRI-mediated pro-inflammatory MC activation could contribute to the development of detrimental cytokine storms.

Study on PRRSV Receptor Genes Differential Expression in Lung Tissues in Different Breeds of Pigs after Infecting with HP-PRRSV

[ Objective] In order to study the susceptibility molecular mechanism of highly pathogenic porcine reproductive and respiratory syndrome virus （ HP- PRRSV） JXA1 isolate on Tibetan pig, Zangmei pig and Yorkshire pig. [ Method ] In the study, real-time quantitative RT-PCR method was established to compare and analyze the differential expression of five porcine reproductive and respiratory syndrome virus （PRRSV） receptor genes （HSPG2, SIGLEC1, CD163, VIM and NMMHC-H A） in lung tissues in Tibetan pig, Zangmei pig and Yorkshire pig before the challenge and at the 4th ,7th and 14th days after the challenge with JXAI isolate. [ Results ] HSPG2 expression in Tibetan pig lung tissues increased significantly at the 4th and 14th days after the challenge with JXAI （ P 〈 0.05 ）, while decreased significantly at the 7th day after the challenge （P 〈 0.05 ）, HSPG2 expression in Zangmei pig lung tissues increased significantly at the 14th day after the challenge （P〈0.05）. SIGLECl expression in Tibetan pig lung tissues increased significantly at the 4th and 14th days after the infection（P 〈 0.05 ）, while SIGLEC 1 expression in Yorkshire pig decreased significantly at the 4th, 7th and 14th days after the challenge （P 〈0. 05 ）. CD163 expression in lung tissues of Tibetan pig and Zangmei pig both increased significantly at the 14th day after the challenge （P 〈 0.05 ）, while CD163 expression in lung tissues of Yorkshire pig decreased significantly at the 7th and 14th days after the challenge （ P 〈 0. 05 ）. VIM expression in lung tissues of Tibetan pig increased significantly at the 7th day after the challenge （ P 〈 0. 05 ）, while which of Yorkshire pig at the 7th day after the challenge decreased significantly （ P 〈 0. 05 ）. NMMHC-II A expression in lung tissues of Zangmei pig increased significantly at the 4th day after the challenge （ P 〈 0. 05 ）, and which of Yorkshire pig increased significantly at the 4th and 14th days after the challenge （P 〈 0. 05 ）. [ Conclusion] SIGLEC1 and VIM genes might be the potential key genes affecting the susceptibility of JXA1 isolate on Tibetan pig, Zangrnei pig and Yorkshire pig. Key words JXA1 isolate; Tibetan pig; Zangmei pig; Yorkshire pig; Porcine reproductive and respiratory syndrome virus receptor genes; Differential expression

Responses of the Toll-like receptor and melanoma differentiation-associated protein 5 signaling pathways to avian infectious bronchitis virus infection in chicks

Avian infectious bronchitis virus(IBV) is a Gammacoronavirus in the family Coronaviridae and causes highly contagious respiratory disease in chickens. Innate immunity plays significant roles in host defense against IBV. Here, we explored the interaction between IBV and the host innate immune system. Severe histopathological lesions were observed in the tracheal mucosa at 3–5days post inoculation(dpi) and in the kidney at 8 dpi, with heavy viral loads at 1–11 and 1–28 dpi,respectively. The expression of m RNAs encoding Toll-like receptor(TLR) 3 and TLR7 were upregulated at 3–8 dpi, and that of TIR-domain-containing adapter-inducing interferon(IFN) β(TRIF) was upregulated at 21 dpi in the trachea and kidney. Myeloid differentiation primary response protein 88(My D88) was upregulated in the trachea during early infection. Tumor necrosis factor receptor-associated factor(TRAF) 3 and TRAF6 were upregulated expression in both tissues.Moreover, melanoma differentiation-associated protein 5(MDA5), laboratory of genetics and physiology 2(LGP2), stimulator of IFN genes(STING), and mitochondrial antiviral signaling protein(MAVS), as well as TANK binding kinase 1(TBK1), inhibitor of kappa B kinase(IKK) ?, IKKα, IKKβ,IFN regulatory factor(IRF) 7, nuclear factor of kappa B(NF-κB), IFN-α, IFN-β, various interleukins(ILs), and macrophage inflammatory protein-1β(MIP-1β) were significantly upregulated in the trachea and downregulated in the kidney. These results suggested that the TLR and MDA5 signaling pathways and innate immune cytokine were induced after IBV infection. Additionally,consistent responses to IBV infection were observed during early infection, with differential and complicated responses in the kidney.

Features of intestinal T-cell lymphomas in Chinese population without evidence of celiac disease and their close association with Epstein-Barr virus infection

Background Intestinal T-cell lymphoma （ITCL） is a heterogeneous lymphoid neoplastic group with variable clinical and pathological features. ITCL in oriental countries is different from enteropathy-type intestinal T-cell lymphoma （ETCL） in relation to celiac disease and Epstein-Barr virus （EBV）. The objective of this study was to investigate the clinicopathological features, immunophenotype, expression of cytotoxic molecule （TIA-1）, T-cell receptor （TCR）-γ gene rearrangement, and Epstein-Barr virus （EBV） latent infection in primary ITCL without celiac disease in Chinese. Methods The clinical data of 42 patients were analyzed, and the patients were followed up. Compared with human reactive lymphoid tissues, in situ hybridization for EBER1/2, polymerase chain reaction for TCR-~/gene rearrangement, and immunohistochemical staining for immunophenotypes, TIA-1 and EBV latent membrane proteins （LMP-1） were investigated. Survival curves of different clinicopathological features, immunophenotypes, expression of LMPI , TCR-γ/gene rearrangement and therapy were analyzed. Results Three fourths of the patients suffered from ITCL in China were men with a peak age incidence in the 4th decade. Common presenting features included fever and hemotochezia. The prognosis was poor with a median survival of 3.0 months. The lesions were mostly localized in the ileocecum and colon. About 38/42 （90. 5% ） patients demonstrated pleomorphic medium-sized on large seen. All 42 patients with ITCL revealed CD45RO cells. Histological features of celiac disease were rarely positive. Neoplastic cells partially expressed T-cell differentiated antigens （CD3ε, CD4, CD8） and NK cell associated antigen （CD56）. The positive frequency of CD3e, CIM, CD8 and CD56 was 28/42 （66.7%） 7/42 （16.7%）, 10/42 （23.8%） and 12/42 （28.6%） respectively. Thirty-nine cells （92. 9% ） expressed TIA-1, but none expressed CD20 and CD68. More than half of the patients （64. 3% , 64.3% and 59.5% ） revealed TCR-γ primers respectively. EBER1/2 was detected in 41 （97.6%） of LMP-1 was 38. 1% （16/42）. gene rearrangement by three different TCR-γ the 42 patients. The expression frequency ofConclusions Primary ITCL without celiac disease in Chinese is a special highly EBV-associated clinicopathological entity. There are few similarities in patients with celiac disease in western countries. A small proportion of primary ITCLs in Chinese and extranodal NK/T-eell lymphoma of nasal type belong to the same speetrum.

Comparison of lentiviruses pseudotyped with S proteins from coronaviruses and cell tropisms of porcine coronaviruses

The surface glycoproteins of coronaviruses play an important role in receptor binding and cell entry. Different coronaviruses interact with their specific receptors to enter host cells. Lentiviruses pseudotyped with their spike proteins(S) were compared to analyze the entry efficiency of various coronaviruses. Our results indicated that S proteins from different coronaviruses displayed varied abilities to mediate pseudotyped virus infection. Furthermore, the cell tropisms of porcine epidemic diarrhea virus(PEDV) and transmissible gastroenteritis virus(TGEV) have been characterized by live and pseudotyped viruses. Both live and pseudoviruses could infected VeroCCL-81(monkey kidney), Huh-7(human liver), and PK-15(pig kidney) cells efficiently. CCL94(cat kidney) cells could be infected efficiently by TGEV but not PEDV. Overall, our study provides new insights into the mechanisms of viral entry and forms a basis for antiviral drug screening.

A possible receptor forβ2 glycoprotein I on the membrane of hepatoma cell line smmc7721

Objectives To study the interaction of beta-2-glycoprotein I (β2GP I ) with the membrane of hepatocytes and determine whether β2GP I participates in HBV infection.Methods Ligand blotting, fluorescence microscopy, and fluorescence activated cell sorter (FACS) analysis were used to detect the specific interaction of β2GP I with the hepatoma cell line smmc7721, the gastric carcinoma cell line SGC7901, and the lymphoma cell line HL-60.Results A specific 40 kDa β2GP I band was observed by ligand blotting in the case of smmc7721 cells. No such band was observed in SGC7901 or HL-60 cells. Fluorescence microscopy also revealed specific binding of FITC-β2GP I to smmc7721 cells, but neither to SGC7901 nor HL-60 cells. FACS analysis demonstrated that the binding rate of FITC-β2GP I to smmc7721 cells was significantly higher than these in SGC7901 and HL-60 cells (P<0. 01). The binding rate to smmc7721 cells did not increase with increasing amounts of FITC-β2GP I .Conclusions There is a specificβ2GP I -binding protein on the membrane of hepatoma cells in cell line smmc7721 which as the β2 GP I receptor may participate in HBV infection of hepatocytes.