Experimental studies on effects of Th1 response in the early phase of Plasmodium yoelii primary infection against reinfection

Aim To investigate the effects of Th1 response in the early phase of plasmodium infection on reinfection Methods Some mice,infected intraperitoneally by P yoelii,were treated with Artemether Tablet in early phase of infection All of mice,including treated and untreated mice,were reinfected with P yoelii or P berghei;both parasitemias were observed by microscopy on Giemsa′s-stained thin blood smears;the levels of cytokines in culture supernatants of splenocytes and antibodies in sera were measured with ELISA Results In nature recovery mice,parasitemia was not found after reinfection with P yoelii,but lower parasitemia was observed after infection with P berghei;comparing with control group,there was lower parasitemia in the mice treated with Artemether Tablet after reinfection with P yoelii or P berghei IFN-γ levels in culture supernatants of splenocytes went up gradually in the early phase of primary infection,but they became higher than that of primary infection after reinfection with P yoelii Conclusion The effects of Th1 response in the early phase of plasmodium infection are very important to resist plasmodium reinfection;the morbidities of reinfection by homologous and heterologous plasmodium or the development of disease are closely related to the parasitemia level of primary infection