METHODS: Anti-retroviral therapy (ART) naïve HIV-seropositive individuals (progressors, n=16) and long-term non-progressors (LTNPs, n=10) were recruited for this study. We employed multi-color flow cytometry on frozen peripheral blood mononuclear cells (PBMCs) to determine iNKT subset frequencies, the levels of co-inhibitory 2B4 expression, and intracellular IFN-γ production. CD1d tetramer was used to characterize iNKT cells.

RESULTS: We report significantly lower level of 2B4 expression on bulk LTNPs iNKT cells as well as on their CD4 subsets compared to HIV progressors. Furthermore, the iNKT cells from LTNPs produced higher amount of IFN-γ than HIV progressors as detected by intracellular cytokine staining. Interestingly, the frequency of 2B4iNKT cells of progressors but not LTNPs significantly correlates with CD4 T cell count, HIV viral load and IFNγ production by iNKT cells.

METHOD: Targeted sequencing of fourteen genes panel was performed to identify the mutations in 29 OI patients with type I, III, IV and V disease. The mutations were determined using Ion Torrent Suite software version 5 and variant annotation was conducted using ANNOVAR. The identified mutations were confirmed using Sanger sequencing and in silico analysis was performed to evaluate the effects of the candidate mutations at protein level.

RESULTS: Majority of patients had mutations in collagen genes, 48% (n = 14) in COL1A1 and 14% (n = 4) in COL1A2. Type I OI was caused by quantitative mutations in COL1A1 whereas most of type III and IV were due to qualitative mutations in both of the collagen genes. Those with quantitative mutations had milder clinical severity compared to qualitative mutations in terms of dentinogenesis imperfecta (DI), bone deformity and the ability to walk with aid. Furthermore, a few patients (28%, n = 8) had mutations in IFITM5, BMP1, P3H1 and SERPINF1.