Role of Monocytes in the Pathogenesis of Dengue

Diseases caused by dengue virus (DENV) are a major public health problem worldwide, considered one of the infections with more prevalence in tropical and subtropical zones of the world. Despite the intense research in the pathogenesis of DENV, this feature is not well understood. One of the main target cells for DENV infection is monocytes; these phagocytes can play a dual role, since they are essential to control viremia, but they also participate in the induction of tissue damage during DENV infection. Monocytes produce different pro-inflammatory cytokines and chemokines in response to infection, and also mediate endothelial damage. In peripheral blood, monocytes can be divided into three different subpopulations, namely classical, intermediate and non-classical, which differ in frequency, cytokine production, among others. Studies in the last years suggest that non-classical monocytes have higher affinity for microvasculature endothelium compared to other type of monocytes, which implies that they could be more involved in the increase of endothelial permeability observed during DENV infection. This review provides a general view of the role of monocytes and their subpopulations in DENV pathogenesis and its effect in viral replication. Finally, the potential contribution of these phagocytes in the alterations of endothelial permeability is discussed.