RESUMO
Present study was aimed to investigate the immunological activities of the 47 kDa glycoprotein antigen from Treponema pallidum and conducted on 24 patients with syphilis, (early, late, spontaneously healed, congenital and treated patients) and on 17 normal healthy controls. Two opposite lymphoproliferative manifestations to the 47 kDa antigen were observed in syphilis patients by H-thymidine incorporation assay. Ten responders (stimulation index [Sl] >4) showed a 3-fold-higher proliferation than the nonresponders, and four of those responders were spontaneously healed patients. Furthermore, analysis by flow cytometry indicated a preferential expansion of CD4' T lymphocytes by the 47 kDa antigen in the spontaneously healed syphilis patients. Stimulation of PBMCs of spontaneously healed syphilis patients with the 47 kDa antigen for greater than 72 hrs resulted in piogressive augmentation of IFN-r, IL-2Ra and IL-2 mRNA measured by RT-PCR, but considerably reduced IL-4 and IL-10 mRNA expression. However, patients with late latent syphilis exhibited more increased IL-4 and IL-10 mRNA expressions in response to the 47 kDa antigen than spontaneously healed syphilis group. In contrast to other groups, when cultured with the 47 kDa antigen very low IFN-#y, IL-2Ra and IL-2 mRNA expressions were shown in early syphilis group. These data suggest that the Th1-predominant cellular responses induced by the 47 kDa antigen may be involved in the clinical outcome of syphilis and provide the immunologic basis for further functional studies regarding the role of the 47 kDa in the immunopathogenesis of syphilis.