RESUMO
Tumor necrosis factor alpha (TNFalpha) plays a key role in orchestrating the complex events involved in inflammation and immune response. The presence of single nucleotide polymorphisms (SNPs) within the promoter region of the TNFa gene has been associated with a number of diseases. The aim of this study was to investigate the distribution of polymorphisms at positions -238 (G/A) and -308 (G/A) at the TNFalpha promoter, and its association to the outcome of different clinical forms of leprosy. Furthermore, the bacteriological index (BI) was evaluated among genotyped multibacillary (MB) patients in order to investigate the possible influence of each polymorphism on the bacterial load. This study included a total of 631 leprosy patients being 401 MB and 230 paucibacillary (PB), that was further separated according to its ethnicity (Afro- and Euro-Brazilians). The combination of SNPs in haplotypes generated three different arrangements: TNFG-G, TNFG-A and TNFA-G. In spite of the marked differences observed in the frequency of the haplotypes along the ethnic groups, no statistical differences were observed in haplotype frequencies between MB and PB patients. The BI analyses showed a lower bacteriological index among the -308 carriers, while the BI of the -238 carriers was higher. Although no significance has been achieved in this analysis regarding the influence of the polymorphisms to the development of the clinical outcome, it seems that in a different stage (among the MB patients) the polymorphisms could contribute to the degree of severity observed.
Assuntos
Hanseníase/genética , Mycobacterium leprae/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , População Negra , Brasil , DNA/química , DNA/genética , Feminino , Haplótipos , Humanos , Hanseníase/imunologia , Hanseníase/microbiologia , Masculino , Regiões Promotoras Genéticas , Análise de Regressão , Fator de Necrose Tumoral alfa/imunologia , População BrancaRESUMO
A técnica de inoculação no coxim plantar de camundongos (técnica de Shepard) possibilita a verificação da resistência aos quimioterápicos e a viabilidade do M. Leprae. O objetivo era avaliar por meio da técnica de Shepard a viabilidade do M. leprae em material de biópsia cutânea proveniente de pacientes hansenianos multibacilares. Biópsias cutâneas e esfregaços de linfas cutâneas em 21 pacientes hansenianos multibacilares após 24 doses do esquema poliquimioterápico (PQT/OMS). A comparação dos resultados dos índices baciloscópico e morfológico entre as duas amostras demonstrou valores significativamente maiores nos índices baciloscópicos das biópsias cutâneas. A concentração do M.Leprae 12 meses após a inoculação mostrou valores inferiores ao referido como padrão de multiplicação, sugerindo que a população bacilar nas biópsias cutâneas de pacientes hansenianos multibacilares após 24 doses da PQT/OMS pode ser considerada não viável
