Elevated levels of circulating galectin-9, a novel immune-modulator, in acute dengue virus Infection reflects disease severity (170.18)

Abstract

Abstract Following a dramatic rise in incidence in recent decades, Dengue virus infection (DENV) is now a significant burden of disease in the tropics and major international public health concern. Currently no treatment or effective vaccine exists. The β-Galactoside-binding lectin, Galectin-9 (Gal-9), functions as pro-apoptotic agent and inducer of pro-inflammatory cytokines from T cells. Here, we sought to evaluate the role of Gal-9 in the pathogenesis of acute DENV in patients presenting with self-limiting dengue fever (DF) and more serious life-threatening dengue hemorrhagic fever (DHF). Blood samples were obtained from 65 patients (mean age: 23±4yrs) hospitalized with DENV from the San Lazaro Hospital, Manila, Philippines in 2010. Plasma Gal-9 was measured by an ELISA method at the critical phase (day4-5) and recovery phase (day7-8) of infection. Our results show that during the critical phase, Gal-9 levels were markedly elevated in DF (1758±1047pg/ml) and DHF(2730±1848pg/ml) compared to uninfected (363±280pg/ml) (p<0.05) controls. These levels of Gal-9 were the highest ever observed in humans. During the recovery phase, Gal-9 levels significantly declined (1170pg/ml and 1140pg/ml) (p<0.05) from peak levels in DF and DHF, respectively, but not to levels observed in uninfected donors. The above findings suggest that Gal-9 levels tracks disease severity during acute DEN, potentially mediate immuno-pathology associated with DHF, and may serve as an indicator of recovery from DENV.