Caracterização genética e biológica de isolados de Toxoplasma gondii (Nicolle e Manceaux, 1909) de animais e humano na região Nordeste do Brasil

Abstract

Toxoplasma gondii is an obligate intracellular coccidian, tissue cyst forming, which causes toxoplasmosis, zoonotic disease of great impact in public health. Three studies were conducted and divided into chapters, which address T. gondii infection in human, farm and wild animals. The first study aimed to isolate and characterize T. gondii strains from tissues of farm animals slaughtered for human consumption on Fernando de Noronha Archipelago, Pernambuco. Two T. gondii isolates were obtained, onde from sheep and one from pig, both isolates were characterized as genotype ToxoDB #146. This is the first report of this genotype in pig and sheep worldwide. The isolates showed different phenotypic and molecular profiles. The second study reported a case of severe congenital toxoplasmosis in newborn baby from Alagoas, that involved the atypical genotype ToxoDB #162, isolated from umbilical cord blood. Genotype result of ROP5 and ROP18 genes could predict the high virulence of the isolate in mice. The third study investigated the presence of apicomplexan protozoans in heart tissue from 39 common marmoset (Callithrix jacchus) from Pernambuco by sequencing a fragment of 18S rDNA gene, by which T. gondii DNA was detected in seven animals (7/39 - 17,9%). Results obtained in the present study contribute to biological and genetic information of T. gondii in animals and human from Alagoas and Pernambuco state.