In endemic areas of Asia, Oceania, Central and South America and in the horn of Africa P. vivax malaria is a major cause of morbidity with 35 million cases annually. In Brazil, the Amazon region concentrates almost all cases and infections registered countrywide, with more than three hundred thousand cases per year. Several evidences suggest that an exacerbated inflammatory response associated to density parasite is likely to aggravate the malaria symptoms. We assessed the haematological and immunological aspects, genetic alterations related to CNVs that could lead to phenotypic alterations, conferring resistance or susceptibility to malaria, as well the presence of polymorphisms in cytokine genes and their association with the infection in patients living in a gold-mining area in a gold-mining in the Brazilian Amazon Region, establishing patterns of immune response characteristic of primary malaria, recurrent malaria and endemic control. Six SNPs (TNFA-308G/A, IFNG+874T/A, IL6-174G/C, IL10-1082G/A, -819C/T, -592C/A) in four genes were determined; blood cell count was conducted on automatic analyzer; plasmatic cytokines IL-6, IL-10, TNF-α and IFN-γ were quantified by flow cytometry and density parasite was estimated by thick blood films with confirmation by nested-PCR; the CNV was estimated by aCGH and association between copy number and phenotypes (parasite load, mean number of clinical infections of malaria and gender) was assessed. The statistical analyzes were performed by Graph-pad prism 6.0 and Bioestat 5.0. No significant association was found between SNPs and malaria infection; cytokine levels were higher in malaria group when compared to endemic control; production of IL-10 was higher in the presence of GCC/GCC haplotype; IFN-γ levels were correlated with previous malaria episodes; malaria patients showed lower platelet numbers, reduction on white blood cells count and an increased monocyte percentage; significant increase in the IL-6 and IL-10 plasmatic levels in both malaria groups; the primary malaria patients displayed the highest significant plasmatic IFN-γ levels; recurrent malaria patients displayed the highest significant plasmatic TNF-α; malaria infection demonstrated correlation between parasite density and TNF-α, IL-6 and IL-10 levels; a total of 112 amplified genes and 12 deleted genes were observed and the CNVs found did not include any gene related to receptors or vivax malaria resistance factors. There were no statistically significant correlations between the clinical and pathological data (parasite load, mean number of clinical infections of malaria and gender) and the presence of CNVs in the patients studied. This study provides additional data on Plasmodium-host immune response and describes the quantitative changes in the human genome in P. vivax infection in an endemic area of garimpo.
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