A subtype-specific peptide-based enzyme immunoassay for detection of antibodies to the G protein of human respiratory syncytial virus is more sensitive than routine serological tests.

Peptides deduced from the central conserved region (residues 158 to 189) of protein G of human respiratory syncytial virus (HRSV) subtypes A and B were used as antigens in subtype-specific enzyme-linked immunosorbent assays (G-peptide ELISAs). These G-peptide ELISAs were compared with seven other serological assays to detect HRSV infection: ELISAs based on complete protein G, on fusion protein F, and on nucleoprotein N; a complement fixation assay; a virus neutralization test; and ELISAs for the detection of immunoglobulin A (IgA) or IgM antibodies specific for HRSV. In paired serum samples from patients with HRSV infection, more infections were diagnosed by the G-peptide ELISA (67%) than by all other serological tests combined (48%). Furthermore, for 16 of 18 patients (89%), the G-peptide ELISAs were able to differentiate between antibodies against HRSV subtypes A and B. This study shows that peptides corresponding to the central conserved region of the attachment protein G of HRSV can successfully be used as antigens in immunoassays. The G-peptide ELISA appeared to be more sensitive than conventional tests for the detection of HRSV antibody titer rises.