Mobilization of Hematopoietic Stem and Progenitor Cells during Dengue Virus Infection.

Hematopoietic stem and progenitor cells (HSPCs) mobilization is the movement of HSPCs from the bone marrow to the peripheral blood or tissue induced by stress. HSPC mobilization is a well-known response to protect the host during infection through urgent differentiation of HSPCs to immune cells. Dengue virus (DENV) infection is known to cause stress in infected humans and the mobilizing capacity of HSPCs during DENV infection in affected patients has not been fully investigated. Here, we investigated whether DENV infection can induce HSPC mobilization and if the mobilized HSPCs are permissive to DENV infection. White blood cells (WBCs) were collected from dengue patients (DENV+) and healthy donors and analyzed by flow cytometry and plaque assay. Elevated HSPCs levels were found in the WBCs of the DENV+ group when compared to the healthy group. Mobilization of HSPCs and homing markers (skin and gut) expression decreased as the patients proceeded from dengue without symptoms (DWoWS) to severe dengue (SD). Mobilizing HSPCs were not only permissive to DENV infection, but infectious DENV could be recovered after coculture. Our results highlight the need for further investigation into HSPC mobilization or alterations of hematopoiesis during viral infections such as DENV in order to develop appropriate countermeasures.