Human haematopoietic progenitor cells infected with dengue virus

Dengue virus (DEN) inhibits proliferation and differentiation of all cell lineages of hematopoietic progenitor cells from bone marrow. We infected these human hematopoietic progenitor cells from healthy donors with DEN-2(16681, Thailand DBF strain} at multiplicity of infection (MOI}=0.1. After 3-4 weeks, we found that the number of colonies for all cell lineages was reduced, in particular the number of BFU-E colonies. Our preliminary data showed that the control sample had 303 BFU-E colonies, 350 CFU-GM colonies, and 87 CFU-GEMM colonies. In contrast, the dengue-infected sample had only 50 BFU-E colonies, 310 CFU-GM colonies, and 40 CFU-GEMM colonies. Moreover, the DEN-2 infected CFU-GM cells were abnormally large with increased size and number of vacuoles. These observations of the reduction in colony number of all hematopoietic progenitor cell lineages can be best explained by assuming that the growth factors for these cells are insufficient or deficient. In addition, there may be some inhibitors which suppress or inhibit colony formation of the hematopoietic progenitor cells. In conclusion, dengue virus may persistently infect a few hematopoietic progenitor cell lineages with little production of their progeny virions while the cells reside in the bone marrow mi croen vi ronment.