Submitted by KEREN BASTOS VALEZI null (keren.valezi@hotmail.com) on 2017-12-18T18:47:58Z No. of bitstreams: 1 Dissertação de Mestrado Keren Valezi.pdf: 1447594 bytes, checksum: 988c2b1fc1fbd371daf1230457df1fa9 (MD5) / Approved for entry into archive by Luciana Pizzani null (luciana@btu.unesp.br) on 2017-12-19T14:03:37Z (GMT) No. of bitstreams: 1 valezi_kb_me-int.pdf: 1447594 bytes, checksum: 988c2b1fc1fbd371daf1230457df1fa9 (MD5) / Made available in DSpace on 2017-12-19T14:03:37Z (GMT). No. of bitstreams: 1 valezi_kb_me-int.pdf: 1447594 bytes, checksum: 988c2b1fc1fbd371daf1230457df1fa9 (MD5) Previous issue date: 2017-11-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A leishmaniose é uma doença antropozoonótica causada pelo protozoário do gênero Leishmania. Ele apresenta três formas clínicas, conhecidas como leishmaniose visceral, leishmaniose cutânea e leishmaniose mucocutânea. A leishmaniose visceral afeta dois milhões de indivíduos anualmente no mundo. Os fato res genéticos envolvidos na interação hospedeiro - parasita foram associados ao desfecho clínico da doença. Este estudo investigou pela primeira vez a associação de polimorfismos nos genes candidatos IL10, NOD2 e TLR1 com leishmaniose visceral na população b rasileira. Para isso, escolhemos três marcadores anteriormente associados a infecções causadas por parasitas intracelulares na população brasileira. Nós genotipificamos 135 pacientes e 380 controles saudáveis. A presença do alelo G do rs4833095 no gene TLR 1 foi fortemente associada à susceptibilidade a esta doença: análise do alelo G (OR 2.04; IC 1.22 - 3.39; p - value 0.0061); Análise do genótipo GG (OR 3,87; 95 %IC 1,85 - 8,08, p - valor 0,0003); Análise de portadores de G (OR 2,5; 95 %IC 1,33 - 5,00; valor p 0,0047) . Para o gene NOD2, também encontramos uma associação para o genótipo AA (OR 2.07 95 %IC 1.05 - 4.05, p - value 0.0335) do polimorfismo rs8057341. Finalmente, poderíamos confirmar a associação do marcador rs1800871 na região promotora do gene IL10 com susceptib ilidade à leishmaniose visceral, para o genótipo TT (OR 2,34; CI 95 %IC 1,11 - 4,94 p - value 0,0245). Conclusão. Nossos dados demonstram pela primeira vez a associação desses genes candidatos com leishmaniose visceral na população brasileira, colocando esses ma rcadores como candidatos fortes na composição de futuros painéis genéticos para prever o risco de infecções na população brasileira e para estudos de meta - análise em visceral leishmaniose / 193614-1

Tuberculosis remains a major public health problem and one of the leading causes of death worldwide. Human genetic factors determine susceptibility to M. tuberculosis (M. tb) infection and predispose to clinical TB. Genome-wide association studies (GWAS) aim to discover human genes associated with susceptibility to TB. Recently, a GWAS conducted by our lab identified a new TB-associated gene ASAP1 that encodes an Arf GTPase-activating protein (GAP). ASAP1 is known to be involved in regulation of actin and membrane remodeling. My Ph.D. included three projects. In my first project, I used RNAi and CRISPR-Cas9 technologies to study the role of ASAP1 in dendritic cells and macrophages, cells that play critical roles during mycobacterial infection. I demonstrated that in these cells ASAP1 is essential for migration and phagocytosis of mycobacteria. I characterized proteins that ASAP1 interacts with during mycobacterial infection. Finally, I found that the ASAP1-mediated pathway regulates expression of a large number of the immune response genes. These findings emphasize the important role of ASAP1 in mycobacterial infection and explain its involvement in TB pathogenesis. In my second project, I was involved in a large study conducted by our laboratory that characterized transcriptional responses to M. tb infection in macrophages from a cohort of 144 healthy subjects. We used RNA-Seq to study transcriptomes of the infected and non-infected macrophages and identified differentially expressed genes. We also genotyped DNA polymorphisms of these subjects and studied the association between genetic variants and levels of gene expression, which allows us to identify expression quantitative trait loci (eQTLs), i.e., DNA polymorphism that affect gene expression. In particular, we identified an eQTL located in the TLR10-TLR1-TLR6 gene cluster. In non-infected macrophages, a group of polymorphisms in this region was associated in cis with the level of expression of TLR1, but not of the other two TLR genes. In M. tb-infected macrophages the same polymorphisms were associated in trans with levels of expression of 37 genes. This network includes essential immune response proteins, including multiple cytokines and chemokines. The discovery of this TLR1-driven network will help to better understand mechanisms of macrophage responses to mycobacterial infection. Our study also identified a DNA polymorphism located upstream of the ARHGAP27 gene, regulating its expression in infected and non-infected macrophages. In our GWAS this polymorphism was associated with TB risk, which implicated ARHGAP27 in TB pathogenesis. The ARHGAP27 protein is a Rho-GAP involved in the endocytic pathway. In my third project, I used CRISPR technology to establish the ARHGAP27-knockout macrophage cell model and characterized the function of ARHGAP27, showing that it is involved in cell migration and phagocytosis of mycobacteria. Taken together, my studies highlighted functional mechanisms implicating TB-associated GAP proteins ASAP1 and ARHGAP27 in mycobacterial infection and TB pathogenesis.