Alterations in Apoptosis of Cord and Adult Peripheral Blood Mononuclear Cells Induced by In Vitro Infection with Respiratory Syncytial Virus

Respiratory syncytial virus (RSV), a major cause of morbidity in children, results in severe lower respiratory tract infections. With an in vitro infection system of isolated cord or adult peripheral blood mononuclear cells, addition of virus to cell cultures resulted in significant reductions in cell deaths, as measured by 2 independent assays: quantitation of cells with subdiploid levels of DNA and cells with DNA strand breaks. Decreased cell death was observed in lymphocytes and monocytes of cord and adult samples, with more dramatic effects evident in cells from cord blood. This may be linked to the increased virulence observed in infants with RSV infection. These data suggest that RSV may be equipped with some mechanism to prevent apoptosis, which is a major component of the host defense system used to eliminate virally infected cells.