Therefore, the present study aimed to verify the role of the recombinant enzymes of S. mansoni, HGPRT and PNP, during experimental schistosomiasis in mice in the phase of early maturity of adult worms and egg laying, since the drug PZQ does not affect these stages of development of the parasite, as a possible immunotherapy candidate for patients in endemic areas. This evidence concerns the gene PNP and schistosomiasis.