RESUMO
INTRODUCTION: Chagas disease (CD), caused by Trypanosoma cruzi, is a major public health issue worldwide affecting 6-7 million people, mainly in Latin America. The complement system plays a crucial role in host immune defense against T. cruzi infection and during the chronic phase of CD; however, the role of the MBL-associated serine protease 1 (MASP1) gene encoding MASP-1, MASP-3, and MAp44 complement proteins has not yet been reported in CD. This study investigated the possible association between MASP1 gene polymorphisms and MASP-3 protein serum levels in chronic CD and its clinical forms. METHODS: Five polymorphisms of MASP1 gene regulatory regions were genotyped in 214 patients with CD and 197 healthy controls (rs7609662 G>A, rs13064994 C>T, rs72549262 C>G, rs1109452 C>T and rs850314 G>A). MASP-3 serum levels were assessed in 70 patients and 66 healthy controls. Clinical data, serum levels of complement proteins (ficolin-2, ficolin-3 and MBL) and inflammatory markers (pentraxin-3 and hsCRP) were also included in the analyses. RESULTS: A significant association of the MASP1 GC_CCA haplotype with CD (padj= 0.002; OR 3.17 [1.19-8.39]) and chronic chagasic cardiomyopathy (CCC) (padj= 0.013; OR 4.57 [1.37-15.16] was observed. MASP-3 and pentraxin-3 levels were positively correlated in the patients (rho = 0.62; p = 0.0001). MASP-3 levels were not associated with MASP1 polymorphisms or CD and its clinical forms. Furthermore, no correlation was observed between MASP-3 levels and that of ficolin-2, ficolin-3, MBL and hsCRP. CONCLUSION: Our findings suggest a possible role for the MASP1 GC_CCA haplotype in susceptibility to chronic CD and CCC clinical forms.
Assuntos
Doença de Chagas , Serina Proteases Associadas a Proteína de Ligação a Manose , Proteína C-Reativa , Doença de Chagas/genética , Proteínas do Sistema Complemento , Humanos , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Polimorfismo GenéticoRESUMO
The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.
Assuntos
Primers do DNA/genética , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Insetos Vetores/parasitologia , Leishmania infantum/genética , Psychodidae/parasitologia , Animais , Feminino , Marcadores Genéticos , Insetos Vetores/classificação , Leishmania infantum/isolamento & purificação , Reação em Cadeia da Polimerase , Psychodidae/classificação , Sensibilidade e EspecificidadeRESUMO
The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.
