Detection of RSV F-specific human mucosal IgA antibody titers utilizing a sensitive electrochemiluminescence platform (67.8)

Abstract

Abstract It has been previously shown that mucosal immune responses play a significant role in mediating protection against respiratory viral infections. Respiratory Syncytial Virus (RSV) is a persistent respiratory virus which infects humans throughout life and can cause severe lower respiratory tract infections, particularly in the elderly. Establishing key biomarkers of vaccine-induced immune response is essential to the development of a successful vaccine. In this study, thirty healthy human donors separated into two age cohorts were evaluated: Young Adult (20 to 30 yrs, n=10) and Elderly (65 to 85 yrs, n=20). Plasma samples from the 30 donors were evaluated for neutralizing antibody titers against wild-type (wt) RSV A2 using a micro-neutralization assay and results showed an average titer of ~10.5+2.2 log2 in both age cohorts. In an effort to investigate additional biomarkers, we evaluated nasal wash samples from these donors for wt RSV A2 and RSV-F specific IgA antibody titers. We utilized both a conventional ELISA and a novel Electrochemiluminescence technology to detect the antigen-specific IgA titers. Results from these studies identified the Electrochemiluminescence platform as being a highly sensitive and powerful technology with a wide enough dynamic range to discern subtle differences in mucosal IgA antibody titers. Utilizing such an approach to detect critical biomarkers in dilute nasal wash samples should benefit clinical vaccine development.