Comparison of the immune response to Ars-BGG in germfree or conventional piglets

Neonatal germfree (GF) colostrum-deprived and conventional (CV) colostrum-fed piglets were immunized IP with p-azo-phenyl-arsonate-bovine gamma globulin (Ars-BGG) in Freund's adjuvant to study the development of the immune response in the absence or presence of maternal antibodies and environmental antigens. Overall, the immune response varied greatly within each group but did not differ in GF from CV piglets statistically. Affinity immunoblot analysis suggested that anti-Ars antibody was more restricted in GF than CV piglets and clonotype shifts occurred more in GF than CV piglets after each antigenic stimulation. In contrast, the clonotype pattern of the anti-BGG antibody was similarly heterogeneous in the two groups. Based on the affinity immunoblot data the antibodies generated to the Ars-haptenic group in CV piglets are more heterogeneous than GF piglets and suggest that clonotype generation is influenced by maternal antibodies and environmental antigens.