Plasmodium Yoelii: Influence Of Antimalarial Treatment On Acquisition Of Immunity In Balb/C And Dba/2 Mice

The effect of antimalarial drugs on immune responses to the malaria infection is evaluated in vivo using two experimental self-cured rodent models. BALB/c and DBA/2 mice were infected by Plasmodium yoelii 17XNL and 17XL strains, respectively, and then treated with different doses of antimalarial drugs: chloroquine (228 mg/kg or 114 mg/kg of the body weight) or artesunate (78 mg/kg or 39 mg/kg). The effect of antimalarial drugs on host immune responses was evaluated by parasitemia, splenocyte IFN-gamma production level, and parasite-specific IgG level in the serum, however,, no significant differences were observed between drug-treated and untreated groups. Moreover, most of the infected mice of all groups showed the ability to resist homologous reinfection (challenged on day 60 post-infection), only a few mice experienced transient, low parasitemia. The rechallenged mice were accompanied by high level of parasite-specific IgG. Therefore, this research implicated that, for BALB/c and DBA/2 mice, chloroquine or artesunate treatment of blood-stage P. yoelii infections does not compromise acquired immunity to malaria in either primary infection or upon rechallenge. (c) 2007 Elsevier Inc. All rights reserved.