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Made available in DSpace on 2018-11-26T16:48:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-07-19 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Para State Research Support Foundation (Fundacao de Amparo a Pesquisa do Estado do Para) CAPPES Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Background: The immune response against Plasmodium vivax immunogenic epitopes is regulated by pro-and anti-inflammatory cytokines that determine antibody levels and class switching. Cytokine gene polymorphisms may be responsible for changes in the humoral immune response against malaria. The aim of this study was to evaluate whether polymorphisms in the TNFA, IFNG and IL10 genes would alter the levels of anti-PvAMA1, PvDBP and -PvMSP-1(19) IgG antibodies in patients with vivax malaria. Methods: Samples from 90 vivax malaria-infected and 51 uninfected subjects from an endemic area of the Brazilian Amazon were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to identify polymorphisms of the genes TNFA (-1031T > C, -308G > A, -238G > A), IFNG (+874T > A) and IL10 (-819C > T, -592C > A). The levels of total IgG against PvAMA1, PvDBP and -PvMSP-1(19) were determined using an enzyme-linked immunosorbent assay (ELISA). Associations between the polymorphisms and the antibody response were assessed by means of logistic regression models. Results: No significant differences were found in the levels of IgG antibodies against the PvAMA-1, PvDBP or PvMSP-1(19) proteins in relation to the studied polymorphisms. Conclusions: Although no associations were found among the evaluated genotypes and alleles and anti-merozoite IgG class P. vivax antibody levels, this study helps elucidate the immunogenic profile involved in the humoral immune response in malaria. Sao Jose Rio Preto Med Sch, Dept Dermatol Infect & Parasit Dis, Sao Jose Do Rio Preto, SP, Brazil Sao Paulo State Univ, Dept Biol, Sao Jose Do Rio Preto, SP, Brazil Univ Fed Sergipe, Dept Biol, Lab Mol Genet & Biotechnol, Sao Cristovao, SE, Brazil Univ Fed Para, UFPA, Inst Biol Sci, Lab Microbiol & Immunol, Belem, Para, Brazil Univ Estadual Campinas, Lab Trop Dis, Dept Genet Evolut & Bioagents, Campinas, SP, Brazil Evandro Chagas Inst, Sect Parasitol, Lab Basic Res Malaria, Belem, PA, Brazil Sao Paulo State Univ, Dept Biol, Sao Jose Do Rio Preto, SP, Brazil CNPq: 472135/2012

S?o Paulo State University. Department of Biology. S?o Jos? do Rio Preto, SP, Brazil / S?o Jos? do Rio Preto Medical School. Department of Skin. Infectious and Parasitic Diseases. S?o Jos? do Rio Preto, SP, Brazil. S?o Jos? do Rio Preto Medical School. Department of Skin. Infectious and Parasitic Diseases. S?o Jos? do Rio Preto, SP, Brazil. S?o Jos? do Rio Preto Medical School. Department of Skin. Infectious and Parasitic Diseases. S?o Jos? do Rio Preto, SP, Brazil / S?o Paulo State University. Department of Biology. S?o Jos? do Rio Preto, SP, Brazil. Federal University of Sergipe. Department of Biology. S?o Crist?v?o, SE, Brazil. Oswaldo Cruz Foundation. Le?nidas and Maria Deane Institute. Manaus, AM, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Pesquisa B?sica de Mal?ria. Bel?m, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Pesquisa B?sica de Mal?ria. Bel?m, PA, Brasil. Oswaldo Cruz Foundation. Le?nidas and Maria Deane Institute. Manaus, AM, Brazil. S?o Paulo State University. Department of Biology. S?o Jos? do Rio Preto, SP, Brazil / S?o Jos? do Rio Preto Medical School. Department of Skin. Infectious and Parasitic Diseases. S?o Jos? do Rio Preto, SP, Brazil / Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Pesquisa B?sica de Mal?ria. Bel?m, PA, Brasil. Background: Humoral immune responses against proteins of asexual blood-stage malaria parasites have been associated with clinical immunity. However, variations in the antibody-driven responses may be associated with a genetic component of the human host. The objective of the present study was to evaluate the influence of co-stimulatory molecule gene polymorphisms of the immune system on the magnitude of the humoral immune response against a Plasmodium vivax vaccine candidate antigen. Methods: Polymorphisms in the CD28, CTLA4, ICOS, CD40, CD86 and BLYS genes of 178 subjects infected with P. vivax in an endemic area of the Brazilian Amazon were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The levels of IgM, total IgG and IgG subclasses specific for ICB2-5, i.e., the N-terminal portion of P. vivax merozoite surface protein 1 (PvMSP-1), were determined by enzyme-linked immuno assay. The associations between the polymorphisms and the antibody response were assessed by means of logistic regression models. Results: After correcting for multiple testing, the IgG1 levels were significantly higher in individuals recessive for the single nucleotide polymorphism rs3116496 in CD28 (p = 0.00004). Furthermore, the interaction between CD28 rs35593994 and BLYS rs9514828 had an influence on the IgM levels (p = 0.0009). Conclusions: The results of the present study support the hypothesis that polymorphisms in the genes of co-stimulatory components of the immune system can contribute to a natural antibody-driven response against P. vivax antigens.

Made available in DSpace on 2018-11-26T17:13:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Polymorphisms in cytokine genes can alter the production of these proteins and consequently affect the immune response. The trihybrid heterogeneity of the Brazilian population is characterized as a condition for the use of ancestry informative markers. The objective of this study was to evaluate the frequency of -1031T>C, -308G>A and -238G>A TNFA, +874 A>T IFNG and -819C>T, and -592C>A IL10 gene polymorphisms and their association with malaria vivax and genomic ancestry. Samples from 90 vivax malaria-infected individuals and 51 noninfected individuals from northern Brazil were evaluated. Genotyping was carried out by using ASO-PCR or PCR/RFLP. The genomic ancestry of the individuals was classified using 48 insertion/deletion polymorphism biallelic markers. There were no differences in the proportions of African, European, and Native American ancestry between men and women. No significant association was observed for the allele and genotype frequencies of the 6 SNPs between malaria-infected and noninfected individuals. However, there was a trend toward decreasing the frequency of individuals carrying the TNF-308A allele with the increasing proportion of European ancestry. No ethnic-specific SNPs were identified, and there was no allelic or genotype association with susceptibility or resistance to vivax malaria. Understanding the genomic mechanisms by which ancestry influences this association is critical and requires further study. Coll Med Sao Jose do Rio Preto, Dept Dermatol Infect & Parasit Dis, Sao Jose Do Rio Preto, SP, Brazil UNIRP, Univ Ctr Rio Preto, Sao Jose Do Rio Preto, SP, Brazil Univ Estadual Campinas, Dept Genet Evolut & Bioagents, Lab Trop Dis Prof Luiz Jacintho da Silva, Campinas, SP, Brazil Sao Paulo State Univ, Dept Biol, Sao Jose Do Rio Preto, SP, Brazil Fed Univ Para, Lab Human & Med Genet, Belem, PA, Brazil Evandro Chagas Inst, Sect Parasitol, Lab Basic Res Malaria, Belem, PA, Brazil Sao Paulo State Univ, Dept Biol, Sao Jose Do Rio Preto, SP, Brazil CNPq: 472135/2012-0

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:02:06Z No. of bitstreams: 1 WOS000253461100001.pdf: 320225 bytes, checksum: 79cd3fc7912611494a290ce14e98c923 (MD5) Made available in DSpace on 2014-02-26T17:02:06Z (GMT). No. of bitstreams: 1 WOS000253461100001.pdf: 320225 bytes, checksum: 79cd3fc7912611494a290ce14e98c923 (MD5) Previous issue date: 2007-12-19 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:19:25Z No. of bitstreams: 1 WOS000253461100001.pdf: 320225 bytes, checksum: 79cd3fc7912611494a290ce14e98c923 (MD5) Made available in DSpace on 2014-05-20T15:19:25Z (GMT). No. of bitstreams: 1 WOS000253461100001.pdf: 320225 bytes, checksum: 79cd3fc7912611494a290ce14e98c923 (MD5) Previous issue date: 2007-12-19 Background: Duffy blood group polymorphisms are important in areas where Plasmodium vivax predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in P. vivax malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria.Methods: the P. vivax identification was determined by non-genotypic and genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP in 330 blood donors and 312 malaria patients from four Brazilian Amazon areas. In order to assess the variables significance and to obtain independence among the proportions, the Fisher's exact test was used.Results: the data show a high frequency of the FYA/FYB genotype, followed by FYB/FYB, FYA/FYA, FYA/FYB-33 and FYB/FYB-33. Low frequencies were detected for the FYA/FY(X), FYB/FY(X), FYX/FY(X) and FYB-33/FYB-33 genotypes. Negative Duffy genotype (FYB-33/FYB-33) was found in both groups: individuals infected and non-infected (blood donors). No individual carried the FY(X)/FYB-33 genotype. Some of the Duffy genotypes frequencies showed significant differences between donors and malaria patients.Conclusion: the obtained data suggest that individuals with the FYA/FYB genotype have higher susceptibility to malaria. The presence of the FYB-33 allele may be a selective advantage in the population, reducing the rate of infection by P. vivax in this region. Additional efforts may contribute to better elucidate the physiopathologic differences in this parasite/host relationship in regions endemic for P. vivax malaria, in particular the Brazilian Amazon region. Ctr Invest Microorganismos, Fac Med Sao Jose Rio Preto, BR-15090000 Sao Jose Dos Campos, Brazil Fac Med Sao Jose Rio Preto, Imunogenet Lab, Sao Jose Dos Campos, SP, Brazil SEAMA Fac, Macapa, Amapa State, Brazil Evandro Chagas Inst, Malaria Program, Belem, Para, Brazil UNESP, IBILCE, Hemoglobin Dis Lab, Sao Jose Dos Campos, SP, Brazil Univ Estadual Campinas, Campinas, SP, Brazil UNESP, IBILCE, Hemoglobin Dis Lab, Sao Jose Dos Campos, SP, Brazil