- Expression of interleukin-4 by recombinant respiratory syncytial virus is associated with accelerated inflammation and a nonfunctional cytotoxic T-lymphocyte response following primary infection but not following challenge with wild-type virus. Bukreyev, A., Belyakov, I.M., Prince, G.A., Yim, K.C., Harris, K.K., Berzofsky, J.A., Collins, P.L. J. Virol. (2005)