Antimalarial antibodies of the immunoglobulin G2a isotype modulate parasitemias in mice infected with Plasmodium yoelii.

摘要: Previous studies have demonstrated the importance of antibodies in mediating immunity to malaria, but relative contribution different immunoglobulin isotypes has not been assessed. In this study, hyperimmune plasma was generated against Plasmodium yoelii and separated by protein A-Sepharose chromatography into fractions containing G1 (IgG1), IgG2a, IgG2b, or IgG3 remaining nonbinding proteins, including IgM. Following concentration, antimalarial titer each isotypic fraction approximately equivalent corresponding isotype plasma. The were passively transferred BALB/c outbred ICR mice prior challenge with virulent P. 17XL CBA/CaJ challenged avirulent 17XNL. Only receiving IgG2a experienced an altered course infection. Immunoprecipitation showed that all four IgG appear recognize a similar set antigens. These results suggest play dominant role modulating parasitemias.