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Malaria impairs T cell clustering and immune priming despite normal signal 1 from dendritic cells.

ABSTRACT: Interactions between antigen-presenting dendritic cells (DCs) and T cells are essential for the induction of an immune response. However, during malaria infection, DC function is compromised and immune responses against parasite and heterologous antigens are reduced. Here, we demonstrate that malaria infection or the parasite pigment hemozoin inhibits T cell and DC interactions both in vitro and in vivo, while signal 1 intensity remains unaltered. This altered cellular behaviour is associated with the suppression of DC costimulatory activity and functional T cell responses, potentially explaining why immunity is reduced during malaria infection.

SUBMITTER: Millington OR

PROVIDER: S-EPMC2014797 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Malaria impairs T cell clustering and immune priming despite normal signal 1 from dendritic cells.

Millington Owain R OR Gibson Vivienne B VB Rush Catherine M CM Zinselmeyer Bernd H BH Phillips R Stephen RS Garside Paul P Brewer James M JM

PLoS pathogens 20071001 10

Interactions between antigen-presenting dendritic cells (DCs) and T cells are essential for the induction of an immune response. However, during malaria infection, DC function is compromised and immune responses against parasite and heterologous antigens are reduced. Here, we demonstrate that malaria infection or the parasite pigment hemozoin inhibits T cell and DC interactions both in vitro and in vivo, while signal 1 intensity remains unaltered. This altered cellular behaviour is associated wi ...[more]

PMID: 17937497

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