A MODEL TO STUDY CYTOKINE PROFILES IN PRIMARY AND HETEROLOGOUSLY SECONDARY DENGUE-2 VIRUS-INFECTIONS

Roles of cytokines in primary and secondary Dengue virus (DV) infectio ns are not completely understood. In this study, we challenged mononuc lear leukocytes (MNLs) obtained from non-immune and DV-1-infected dono rs with DV-2 in vitro to mimic primary and heterologously secondary DV -2 infections, respectively. We found that MNLs in response to DV-2 co uld release a large amount of interleukin-1 (IL-1 beta) and tumor necr osis factor alpha (TNF alpha). However, IL-1 beta and TNF alpha releas ed by MNLs with primary or heterologously secondary exposure to DV-2 w ere not significantly different. In contrast, MNLs with heterologously secondary DV-2 infections produced significantly higher amount of int erferon gamma (IFN gamma) than those with primary DV-2 infections. The se results suggest that IFN gamma, but not TNF alpha or IL-1 beta, may in part participate in the pathogenesis of Dengue shock syndrome (DSS ) frequently found in heterologously secondary DV-2 infections.