Systemic and mucosal antibody response to N SRS administered intra-nasally.

<p>BALB/c mice were administred 10 µg N SRS and/or 5 µg LT(R192G) twice i.n. at two weeks interval. Individual sera were collected at day 0, 14 and 28 and individual BAL supernatants at day 28. (A) Total Ig, (B) IgG1 (white bars) and IgG2a (black bars) anti N antibodies in serum. (C) total Ig (white bars) and IgA (black bars) in BAL. Titers were determined in an endpoint dilution ELISA assay on plates coated with N SRS. Each bar represents the mean and SEM of 5–6 mice. Titers are shown with logarithmic scale (data from one out of three experiments with similar results). (D) Systemic and mucosal antibodies raised against N SRS recognize RSV-A2. Total Ig, IgG1, IgG2a and IgA in BAL or serum were titrated by ELISA on plates coated with RSV infected HEp-2 versus non infected HEp-2 cells. Data shown are ODx1000 at dilution 270 for sera samples and dilution 27 for BAL samples, after subtracting OD value of non infected HEp2. Each bar represents the mean and SEM of 5–6 mice (Data from one out of two experiments with similar results).