T lymphocyte responses to heterologous secondary dengue virus infections.

Center for Infectious Disease and Vaccine Research, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
Annals of the New York Academy of Sciences (Impact Factor: 4.38). 09/2009; 1171 Suppl 1:E36-41. DOI: 10.1111/j.1749-6632.2009.05055.x
Source: PubMed

ABSTRACT The available evidence suggests that plasma leakage in dengue hemorrhagic fever is caused by the action of circulating mediators on the vascular endothelium, and that the host immune response is a critical determinant of this response. We have been exploring the role of dengue virus-specific T lymphocytes in the immunopathogenesis of plasma leakage. Memory dengue virus-specific T cells induced during a primary dengue virus infection are reactivated by the heterologous viral serotype during a secondary infection to expand to high levels and produce a skewed cytokine profile. Investigations are underway to identify the immunologic profiles associated with increased or decreased risk for severe disease.

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