Quantitative effects of palivizumab and donor-derived T cells on chronic respiratory syncytial virus infection, lung disease, and fusion glycoprotein amino acid sequences in a patient before and after bone marrow transplantation.

A patient with respiratory syncytial virus (RSV) infection and severe combined immunodeficiency was studied during a 3-month period of bone marrow transplantation and palivizumab infusion. No RSV isolates with palivizumab escape mutations were identified. Donor lymphocytes, including CD8 cells, appeared to markedly reduce the RSV load but increased the pulmonary symptoms. Immunosuppressive therapy ameliorated lung disease but allowed the RSV load to rebound.