de Sá NBR, Ribeiro-Alves M, da Silva TP, et al. - Given the lack of data regarding the risk factors for immune reconstitution inflammatory syndrome (IRIS), a pathological inflammatory reaction observed in some tuberculosis (TB)-HIV co-infected individuals treated for both diseases simultaneously, researchers here examined the relation of HLA-B, HLA-C, and KIR genotypes with TB, HIV-1 infection, and IRIS onset. Participants were categorized into four groups: Group 1- TB+/HIV+ (n = 88; 11 of them with IRIS), Group 2- HIV+ (n = 24), Group 3- TB+ (n = 24) and Group 4- healthy volunteers (n = 26). Among the individuals with TB as the outcome, heightened risk for TB onset was observed in correlation with KIR2DS2, whereas the protective effect of HLA-B*08 and female gender was observed against TB onset. Among HIV-infected patients, not carrying KIR2DL3 and carrying HLA-C*07 were connected with protection against TB onset. They observed an increased risk for IRIS onset to be linked with having a CD8 count ≤ 500 cells/mm³; carrying the KIR2DS2 gene, the HLA-B*41 allele, the KIR2DS1 + HLA-C2 pair; and not carrying the KIR2DL3 + HLA-C1/C2 pair, and the KIR2DL1 + HLA-C1/C2 pair. These findings support that KIR, HLA-B, and HLA-C genes are related to the immunopathogenic mechanisms related to the clinical conditions studied here. They identified this work as one of the first studies illustrating significant correlations of the HLA-B*41 allele, the KIR activating receptor gene KIR2DS2, and a combination of KIR/HLA-C pairs with increased risk of IRIS onset among TB-HIV co-infected individuals.