Induction of CD4+ T-Cell-Independent Immunoglobulin Responses by Inactivated Influenza Virus

AUTOR(ES)

Sha, Zhiyi

FONTE

American Society for Microbiology

RESUMO

Through cognate interaction between antigen-specific B-cell and CD4+ αβ T cells, the CD4+ αβ T cells secrete cytokines that initiate immunoglobulin (Ig) class switching from IgM to IgG. In this study, we show that formalin-inactivated influenza PR8 virus induces virus-specific IgM and IgG responses in the absence of CD4+ T cells and that all four subclasses of IgG are produced. The immunized CD4-deficient mice were also found to be completely protected against lethal infection with live, pathogenic influenza virus. The ability of CD4+ T-cell-deficient mice to generate these IgG responses was not found to be impaired when these mice were depleted of CD8+ T cells with an anti-CD8 monoclonal antibody. In contrast, αβ T-cell-deficient mice (TCRβ−/−) were not found to produce significant amounts of IgG upon immunization with formalin-inactivated PR8 virus. These results suggest that CD4− CD8− double-negative αβ T cells are playing a role in regulating Ig class switching in the absence of CD4+ T cells.

Documentos Relacionados

• T-cell-independent elimination of Borrelia turicatae.
• T-Cell-Independent Immunoglobulin G Responses In Vivo Are Elicited by Live-Virus Infection but Not by Immunization with Viral Proteins or Virus-Like Particles
• T-cell-independent and T-cell-dependent B-cell responses to exposed variant surface glycoprotein epitopes in trypanosome-infected mice.
• T-Cell-Independent Responses to Borrelia burgdorferi Are Critical for Protective Immunity and Resolution of Lyme Disease
• Human CD4+ T-cell repertoire of responses to influenza A virus hemagglutinin after recent natural infection.