Effect of respiratory syncytial virus infection on binding of Neisseria meningitidis and Haemophilus influenzae type b to a human epithelial cell line (HEp-2).

It has been suggested that individuals might be more readily colonized with bacteria that cause meningitis through enhanced binding of the bacteria to virus-infected epithelial cells. As respiratory syncytial virus (RSV) affects infants and children in the age group also susceptible to bacterial meningitis, we tested the hypothesis that infection of HEp-2 cells by RSV might enhance binding of Neisseria meningitidis or Haemophilus influenzae type b (Hib). Attachment of fluorescein-labelled bacteria to HEp-2 cells was measured by flow cytometry, and RSV-infected cells bound significantly more meningococci (P < 0.001) and Hib (P < 0.01) than uninfected cells. Although the isolates expressed different antigenic characteristics (3 meningococci and 5 Hib), all showed a similar pattern of binding. The results are discussed with reference to the methods used for detection of bacterial binding and to interactions that might explain the increased binding to RSV-infected cells.