KIR2DL2, KIR2DL5A and KIR2DL5B Genes Induce Susceptibility to Dengue Virus Infection, while KIR3DL3 and KIR2DS5 Confer Protection.

Background and Objectives: Dengue fever (DF), an emerging and re-emerging viral disease, is a major public health problem. The aim of this study was to investigate the influence of KIRs genes polymorphism and KIRs genotypes in susceptibility to dengue virus infection and disease severity in a population from Burkina Faso through a case-control study. Methods: KIRs genes determination was performed using PCR-SSP in 50 patients infected by dengue virus (DENV) and 54 Healthy controls (HC) subjects who had never been infected. Results: Data analysis showed significant association between frequencies of three KIR genes and dengue virus infection (DF): KIR2DL2 (OR: 7.32; IC: 2.87-18.65; P < 0.001); KIR2DL5A (OR: 15.00, IC: 5.68-39.59; P < 0.001) and KIR2DL5B (OR: 11.43; IC: 4.42-29; P < 0.001). While, KIR3DL3 (OR: 0.13, IC: 0.052-0.32; P < 0.001) and KIR2DS5 (OR: 0.12; IC: 0.04-0.30; P < 0.001) were associated with protection against DF. KIR2DL4 (OR: 9.75; IC95%: 1.33-70.97; p: 0.03) and KIRD3DL1 (OR: 12.00; IC95%: 1.60-90.13; p: 0.02) were associated with an increased risk in the development of secondary dengue infection (SDI). Conclusion: The results suggest a contribution of KIR2DL2, KIR2DL5A, and KIR2DL5B genes in the susceptibility of DF development. In contrast, KIR3DL3 and KIR2DS5 were associated with protection against DF development by enhancing both innate and acquired immune responses.

KIR2DL5B and HLA DRB1*12 alleles seems to be associated with protection against HIV-1 in serodiscordant couples in Burkina Faso.

The human immunodeficiency virus (HIV) belongs to the Retroviridae family and remains a public health problem in sub-Saharan Africa. Recent reports from WHO have shown that 33 million people died from HIV infections. HIV is one of the most serious fatal human diseases of the 20th and 21st centuries. However, variations in genetic and immunological factors are associated with protection against HIV infection in uninfected people exposed to HIV. This is the case with naturals killers which play an important role in the progression or regression of HIV infection. The objective of this study is to characterize certain HLA (human leukocyte antigen) class II genes and KIR genes in HIV-1 serodiscordant couples in Burkina Faso. This study was carried out at Burkina Faso among nineteen (19) HIV-1 serodiscordant couples. Classical multiplex PCR (SSP-PCR) was used to characterize the presence or absence of the KIR genes and certain class II HLAs (DRB1*11 and DRB1*12). The characterization of the KIR and HLA genes DRB1*11, DRB1*12 in this study demonstrated that the inhibitor KIR2DL5B, would confer protection against HIV-1 infection in seronegative partners (odd ratio [OR] = 0.13 [0.02-0.72] and p = 0.029), and the HLA DRB1*12 allele was associated with protection against HIV-1 infection in seronegative partners (OR = 0.16 [0.03-0.77] and p = 0.038). AA and Bx haplotypes were not found to be associated with HIV-1 infection in serodiscordant couples. This study confirms the involvement of the KIR genes in viral pathologies such as HIV-1 infection. Future larger-scale studies may provide a better understanding of the molecular mechanism by which the KIR haplotype and combination of KIR/HLA are associated with protection against HIV infection.

Major Polymorphisms of Genes Involved in Homocysteine Metabolism in Malaria Patients in Ouagadougou, Burkina Faso.

This study analyzed the four main polymorphisms of the genes in homocysteine metabolism in malaria patients. Forty-two randomly selected subjects, diagnosed positive for Plasmodium falciparum, were included. The four genotypes were detected by real-time PCR using the MTHFR 677C>T, MTHFR 1298A>C, MTR 2756A>G, and MTRR 66A>G detection kit (Sacace Biotechnologies REF: T01002-96-S). The results revealed frequencies of 90% 677CC, 10% 677CT, and 00% 677TT for MTHFR C677T; 78.6% 1298AA, 19% 1298AC, and 2.4% 1298CC for MTHFR A1298C; 61.9% 2756AA, 33.3% 2756AG, and 4.8% 2756GG for MTR A2756G; and 50% of 66AA, 45% of 66AG, and 5% of 66GG for MTRR A66G. Correlations were found between A2756G MTR genotypes and parasitaemia (P = 0.02), MTRR A66G and hemoglobin genotypes (P = 0.009), and MTHFR A1298C and sex (P = 0.01). This study demonstrated for the first time an association between the A2756G MTR alleles and Plasmodium falciparum malaria in Burkina Faso and gave an overview of the genotypic distribution of the major SNPs influencing the metabolism of homocysteine.