Dengue virus inhibits human hematopoietic progenitor growth in vitro

Dengue disease, whether it be classical dengue fever (DF), dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS), is frequently associated with hematologic disorders. The underlying cause of these abnormalities is unknown. To determine if an inhibitory effect on human hematopoietic progenitor growth can be observed, normal cord blood mononuclear cells were exposed to low-passaged clinical isolates from DF, DHF, and DSS patients and to the prototype strain of dengue-3 virus (H-87). In primary methylcellulose cultures, there was no inhibition of colony formation. After an initial 8-day liquid culture, inhibition was observed with the isolates, but strain H-87 had no effect. Furthermore, isolates from patients with DSS showed a more potent inhibitory effect. These data represent the first documented study of in vitro impaired progenitor cell growth by dengue virus and suggest that this inhibition could be dependent upon the isolate tested.