DIFFERENTIAL EXPRESSION OF THE ESTROGEN-REGULATED PROTOONCOGENES C-FOS, C-JUN, AND BCL-2 AND OF THE TUMOR-SUPPRESSOR P53 GENE IN THE MALE-MOUSE CHRONICALLY INFECTED WITH TAENIA-CRASSICEPS CYSTICERCI

Chronic infection with Taenia crassiceps cysticerci produces a 200-fol d increase in serum estradiol levels in male mice. The aim of this stu dy was to investigate the expression pattern of c-fos and c-jun, two e stradiol-regulated genes, as well as that of p53 and bcl2 in the teste s, spleen, and thymus of male mice infected with T. crassiceps cystice rci. In parasitized animals the c-fos mRNA content was significantly i ncreased in all tissues studied, whereas the c-jun mRNA content was in creased only in the thymus. The p53 mRNA content was markedly reduced in all tissues of the parasitized animals analyzed, whereas bcl-2 gene expression was abolished in the thymus. On the other hand, thymic cel l analysis performed by flow cytometry showed a diminution in the cont ent of CD3(+), CD4(+), and CD8(+) subpopulations in the parasitized mi ce. Our results suggest that the increase in estradiol levels of the h ost should change the expression pattern of several genes that partici pate in apoptosis regulation in the thymus of male mice during chronic infection with T. crassiceps cysticerci.