Study On Homogeneity And Differentia Of Toxoplasma Gondii Isolates From China, RH Strain And Its Mutants

Toxoplasma gondii (T. gondii) is a widespread protozoan parasite which can invade almost any nucleated cell in a broad host range, including human, animals. Although normally nonpathogenic in adults infected with T.gondii, however, during pregnancy T.gondi is a cause of congenital toxoplasmosis resulting in premature delivery, abortion, death in foetus, and abnormality or amentality of newborns. Especially in the immunocompromised hosts such as with tumor, transplanted organs, AIDS etc., T. gondii as an opportunistic pathogen, can over-grow and cause a potentially fatal illness lead to death of these patients. Now infection of T.gondii or toxoplasmosis has become a severe problem of agricultural economy and public health problem.At present, all T. gondii isolated from human or animals considers as one species, and be divided into murine virulent and avirulent, or three clonal lineages groups (Type I,Type II and Type III). However previous typing studies cannot completely account for difference of biological characterization including virulence, antigen kinds, host immune reaction, ...etc. among different isolates. Therefore, to understand homogeneity and differentia of isolates remain to be a problem.