Hla-C genetic diversity and evolutionary insights in two samples from Brazil and Benin.

Human leukocyte antigen-C (HLA-C) is a classical HLA class I molecule that binds and presents peptides to cytotoxic T lymphocytes in the cell surface. HLA-C has a dual function because it also interacts with Killer-cell immunoglobulin-like receptors (KIR) receptors expressed in natural killer and T cells, modulating their activity. The structure and diversity of the HLA-C regulatory regions, as well as the relationship among variants along the HLA-C locus, are poorly addressed, and few population-based studies explored the HLA-C variability in the entire gene in different population samples.

HLA-A promoter, coding, and 3'UTR sequences in a Brazilian cohort, and their evolutionary aspects.

HLA-A is the second most polymorphic locus of the human leucocyte antigen (HLA) complex encoding a key molecule for antigen presentation and NK cell modulation. Many studies have evaluated HLA-A variability in worldwide populations, focusing mainly on exons, but the regulatory segments have been poorly characterized. HLA-A variability is particularly high in the segment encoding the peptide-binding groove (exons 2 and 3), which is related to the antigen presentation function and the balancing selection in these segments.

HLA-G variability and haplotypes detected by massively parallel sequencing procedures in the geographicaly distinct population samples of Brazil and Cyprus.

The HLA-G molecule presents immunomodulatory properties that might inhibit immune responses when interacting with specific Natural Killer and T cell receptors, such as KIR2DL4, ILT2 and ILT4. Thus, HLA-G might influence the outcome of situations in which fine immune system modulation is required, such as autoimmune diseases, transplants, cancer and pregnancy. The majority of the studies regarding the HLA-G gene variability so far was restricted to a specific gene segment (i.

HLA-E coding and 3' untranslated region variability determined by next-generation sequencing in two West-African population samples.

HLA-E is a non-classical Human Leucocyte Antigen class I gene with immunomodulatory properties. Whereas HLA-E expression usually occurs at low levels, it is widely distributed amongst human tissues, has the ability to bind self and non-self antigens and to interact with NK cells and T lymphocytes, being important for immunosurveillance and also for fighting against infections. HLA-E is usually the most conserved locus among all class I genes.

MicroRNAs targeting the immunomodulatory HLA-G gene: a new survey searching for microRNAs with potential to regulate HLA-G.

The HLA-G gene is a non-classical class I MHC, responsible for modulating immune responses by inhibiting Natural Killer and cytotoxic T cells, presenting a crucial role in maternal tolerance to the fetus. In non-pathological conditions, its expression is restricted to certain tissues such as cornea and placenta. The HLA-G 3' untranslated region (3'UTR) has been reported to play an important role in the control of mRNA and protein levels, and polymorphisms in this region may influence mRNA stability and microRNA binding.

Insights into HLA-G Genetics Provided by Worldwide Haplotype Diversity.

Human leukocyte antigen G (HLA-G) belongs to the family of non-classical HLA class I genes, located within the major histocompatibility complex (MHC). HLA-G has been the target of most recent research regarding the function of class I non-classical genes. The main features that distinguish HLA-G from classical class I genes are (a) limited protein variability, (b) alternative splicing generating several membrane bound and soluble isoforms, (c) short cytoplasmic tail, (d) modulation of immune response (immune tolerance), and (e) restricted expression to certain tissues.