RESUMO
Background: Human cytomegalovirus (HCMV) is a leading cause of virally induced congenital disorders and morbidities in immunocompromised individuals, ie, transplant, cancer, or acquired immune deficiency syndrome patients. Human cytomegalovirus infects virtually all cell types through the envelope glycoprotein complex gH/gL/gO with or without a contribution of the pentameric gH/gL/pUL128L. Together with gH/gL, the HCMV envelope glycoprotein B (gB) contributes to the viral fusion machinery. Methods: We previously showed that gB is a ligand for the C-type lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) contributing to HCMV attachment to and infection of DC-SIGN-expressing cells. However, the features of the DC-SIGN/gB interaction remain unclear. To address this point, the role of glycans on gB and the consequences of mutagenesis and antibody-mediated blockades on both partners were examined in this study. Results: We identified DC-SIGN amino acid residues involved in this interaction through an extensive mutagenesis study. We also showed the importance of high-mannose N-glycans decorating the asparagine residue at position 208, demonstrating that the antigenic domain 5 on gB is involved in the interaction with DC-SIGN. Finally, antibody-mediated blockades allowed us to identify DC-SIGN as a major HCMV attachment receptor on monocyte-derived dendritic cells. Conclusions: Taken together, these results have permitted us to fine-map the interaction between DC-SIGN and HCMV gB.
Assuntos
Moléculas de Adesão Celular/metabolismo , Citomegalovirus/fisiologia , Células Dendríticas/virologia , Interações Hospedeiro-Patógeno , Lectinas Tipo C/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Moléculas de Adesão Celular/genética , Células Cultivadas , Análise Mutacional de DNA , Humanos , Lectinas Tipo C/genética , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Polissacarídeos/metabolismo , Ligação Proteica , Mapeamento de Interação de Proteínas , Receptores de Superfície Celular/genética , Receptores Virais/genética , Proteínas do Envelope Viral/genética , Ligação ViralAssuntos
Complexo Antígeno-Anticorpo/imunologia , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Interleucina-17/imunologia , Idoso , Idoso de 80 Anos ou mais , Complexo Antígeno-Anticorpo/metabolismo , Artrite Reumatoide/fisiopatologia , Biomarcadores/metabolismo , Estudos de Casos e Controles , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-17/metabolismo , Masculino , Valor Preditivo dos Testes , Valores de Referência , Medição de Risco , Índice de Gravidade de DoençaRESUMO
Dogs with lymphoma are established as good model for human non-Hodgkin lymphoma studies. Canine cell lines derived from lymphomas may be valuable tools for testing new therapeutic drugs. In this context, we established a canine T-cell line, PER-VAS, from a primary aggressive T-cell lymphoma with large granular morphology. Flow cytometric analysis revealed a stable immunophenotype: PER-VAS cells were positively labelled for CD5, CD45, MHC II and TLR3, and were negative for CD3, CD4 and CD8 expression. Although unstable along the culture process, IL-17 and MMP12 proteins were detectable as late as at passages 280 and 325i.e. respectively 24 and 29 months post isolation. At passage 325, PER-VAS cells maintained the expression of IL-17, CD3, CD56, IFNγ and TNFα mRNAs as shown by RT-PCR analysis. Stable rearrangement of the TCRγ gene has been evidenced by PCR. PER-VAS cells have a high proliferation index with a doubling time of 16.5h and were tumorigenic in Nude mice. Compared to the canine cell lines already reported, PER-VAS cells display an original expression pattern, close to NKT cells, which makes them valuable tools for in vitro comparative research on lymphomas.