MONOCLONAL-ANTIBODIES INHIBITING INVASION OF CULTURED-CELLS BY EIMERIA-TENELLA SPOROZOITES

Monoclonal antibodies (MoAbs) secreted by 12 hybridomas and reactive w ith the surface antigens of E. tenella sporozoites were produced. Thes e MoAbs designated as KC-1 to KC-12 were characterized as IgG(3) kappa . In Western blot analysis, these MoAbs reacted with only one polypept ide band of sporozoite antigens having a molecular mass of 25 kDa. All the MoAbs were reactive with sporozoites, trophozoites, immature and mature first generation schizonts, first generation merozoites, and th e interior structure of sporulating oocysts of E. tenella, however, no t with any of the methanol-fixed sporozoites of E. acervulina, E. miti s, E. maxima, E. brunetti, E. necatrix and E. praecox. Invasion of pri mary culture of chicken kidney cells by E. tenella sporozoites was sig nificantly inhibited by several of the MoAbs. These results suggest th at these MoAbs recognizing the E. tenella-specific surface molecule ar e involved in the invasion of sporozoites into host cells.