Maternal antibodies enhance systemic and local immune responses after early mucosal immunization in a porcine model

Abstract

Event Abstract Back to Event Maternal antibodies enhance systemic and local immune responses after early mucosal immunization in a porcine model Edgar R. Guzman-Bautista1, Carlos E. Garcia-Ruiz2, Alicia L. Gama2, Carmen Ramirez-Estudillo1, Oscar I. Rojas1 and Marco A. Vega-Lopez1* 1 CINVESTAV-IPN, Infectomics and Molecular Pathogenesis, Mexico 2 Universidad Nacional Autonoma de Mexico, Facultad de Estudios Superiores Cuautitlan, Mexico In newborn mammals, maternal antibodies (MatAb) confer protection against antigenic challenges, although it has been also reported a suppressive effect on neonatal immune response to immunization (1, 2). We evaluated the immune response to ovoalbumin (OVA) after mucosal immunization on 7 and 14 days (7d, 14d) old SPF Vietnamese minipigs from negative (OVA-) or previously immunized (OVA+) sows. Sows were intramuscularly immunized to OVA 30 days before farrowing. Maternal anti-OVA IgG and IgA were detected in colostrum and serum and were intestinally absorbed by the offspring during the first three days of life. These antibodies were detected in piglets’ serum, but not in mucosal secretions (saliva, nasal secretion). The own systemic (serum) anti-OVA IgG and IgA responses were significantly higher in piglets immunized at 7d of life, from OVA+ sows, compared with piglets from OVA- sows (figure 1A) and similar to piglets immunized at 14d of age. Also the own anti-OVA IgA response in nasal secretion was higher in OVA+ 7d piglets (figure 1B) and in saliva of OVA+ 14d piglets (not shown). This specific immune response lasted far beyond MatAb halflife. In our hands, the systemic suppressive effect of MatAb, reported by others at early immunization, was not detected. On the contrary, a stimulating effect was found with MatAb in one week old immunized piglets, both in systemic and mucosal compartments and this effect disappeared in 14d old immunized piglets. Ag specific maternal factors (anti-Id Ab?) (3) may positively favor the immune response in immature young animals. These results open the possibility to induce effective early systemic and mucosal immune responses in the young through immunization, even in the presence of MatAb. Figure 1. Serum IgG (A) and nasal IgA (B) anti-ovoalbumin (OVA) antibodies in piglets immunized at 7 days old receiving maternal antibodies (black squares, OVA+ sow) or not (white squares, OVA- sow). Piglets were subcutaneously (SC) immunized twice (days 0 and 10) and intranasally boosted (days 20 and 55) with OVA. Each point is the average of 6 (OVA+) or 5 (OVA-) pigs +/- SEM. Unpaired t-test *P<0.05, **P<0.01, ***P<0.001. Scales graphs have different units. Figure 1 Acknowledgements Supported by grants from CONACyT (234097) and ICyTDF (323/09), Mexico. Thanks to DVM Manuel Flores and Daniel Cortes for technical assistance. References