A 23-kDa recombinant antigen of Cryptosporidium parvum induces a cellular immune response on in vitro stimulated spleen and mesenteric lymph node cells from infected mice

In the present study, we focused on a 23-kDa antigen, Cp23, which has been shown to be a major target of humoral immune responses in Cryptosporidium p arvum infections and is present in both the sporozoite and merozoite stages . Recombinant Cp23 antigen was shown to stimulate a specific proliferative response by splenocytes and mesenteric lymph node cells from infected inter feron gamma knockout BALB/c mice. Cp23 stimulation also induced TNF-alpha, IL-2, and IL-5 mRNA production by spleen cells from infected animals. Tn co ntrast, IL-12 mRNA was decreased by Cp23 stimulation compared with unstimul ated splenocytes. These data suggest that, as with humoral responses, Cp23 is an important target of cellular immune responses in experimental C. parv um infections. The potential role of this antigen in conferring protective immunity is also discussed, (C) 2000 Academic Press.