HUMAN B CELLS: A NEWLY DESCRIBED TARGET OF INFECTION BY OLD AND NEW WORLD HANTAVIRUSES

MALEKI K; SASIAIN M DEL C; SCHIERLOH P; CARLES SOLA RIERA; GRUPTA S; KLINGSTRÖM J; GARCÍA, MARINA; IGLESIAS A; MARTINEZ V

Mar del Plata

Congreso; LXVI Reunión anual de la Sociedad Argentina de Inmunología; 2018

Hantavirus are enveloped RNA viruses that belong to the Hantaviridae family. Old World hantaviruses cause Haemorrhagic Fever with Renal Syndrome (HFRS), whereas New World hantaviruses are responsible for Hantavirus Pulmonary Syndrome (HPS). The main target of infection are microvascular endothelial cells. In previousstudies, we observed a massive polyclonal activation of circulating B cells in HPS patients from Argentina and an increased risk for B cell lymphoma after HFRS in Sweden, which prompted the question whether these cells may constitute an alternative target for hantavirus infection.To test this hypothesis, a B cell line (BJAB) and purified B cells from healthy blood donors (n=4) were exposed to HTNV -Old World- and ANDV -New World- species (MOI 1) or UV-inactivated virus, as negative controls. Supernatants and cells were collected at subsequent time points (6-96h). To asses for infection, the presence of nucleocapsid protein (NP) in fixed cells (confocal microscopy) or cell lysates (western blot) was determined. Genomic RNA S-segment was quantified by qRT-PCR to measure viral replication. For production of progeny virus, supernatants were assessed by a focus forming unit assay.NP from both species was detected by WB in both BJAB and purified B cells, as well as by microscopy in BJAB, confirming that human B cells are indeed susceptible to infection by both hantaviruses. Furthermore, both species replicated in the two cell types, confirmed by increasing copy number (ΔΔCt) over time (p