Background: Major Human Histocompatibility complex (MHC or HLA in humans) has been associated to autoimmune diseases. However, only statistical phenomenological and no pathogenetic description has been reached after decades. This shows that MHC single locus association studies are probably useless for HLA/diseases association.
View Article and Find Full Text PDFGastric cancer ranks fifth in both world prevalence and lethality, with a 5-year survival of less than 30%. HLA-G, a non-classical class I HLA gene, has emerged as a potential marker for cancer susceptibility and prognosis due to its immunomodulatory properties. Its level of expression is regulated by polymorphisms in the 3' untranslated region (3'UTR) polymorphisms, which form various combined haplotypes (UTR-1 to -9).
View Article and Find Full Text PDFThe Human Leukocyte Antigen (HLA) system contains a set of genes involved at many levels in the innate and adaptive immune response. Among the non-classical HLA class I genes, HLA-G stands out for the numerous studies about its pivotal role in regulating/modulating immune responses. Also, its involvement in extravillous cytotrophoblast function, viral infections, autoimmunity, and cancer has been extensively documented.
View Article and Find Full Text PDFThe relationship between microbiota and the immune system is complex and characterized by the ways in which microbiota directs immune function interactions, both innate and acquired and also keeps activating the immune system throughout an individual's life. In this respect, the human Major Histocompatibility Complex (MHC, referred to as HLA in humans) plays a crucial role and is also established in self-defense against microbes by presenting microbial-derived peptides to the immune cells. However, this assumption has some unclear aspects that should be investigated.
View Article and Find Full Text PDFHLA studies in Crete show that this population is related to North Africans and also Iberians. This may be a reflection of a common prehistoric first Europeans relationships with North Africans and drying Saharan emigration after 10,000 years BC; it may be specifically represented by a primitive and early cult to the bull in both Cretan (Minoan) and Iberian populations. In the present study, unrelated Cretans representing different Island parts have been studied for class II HLA-DRB1 and -DQB1 alleles.
View Article and Find Full Text PDFYazd City (1,200,000 inhabitants) is placed in the middle of its Iran desert province and it was constructed on a oasis in ancient times.However,it was a central point on the Silk Road and merchants from both Asia and Mediterranean/European areas crossed through Yazd City.We have studied HLA-A,-B,-DRB1 and DQB1 alleles in Yazd population.
View Article and Find Full Text PDFNahua population (also named Aztec or Mexica) was studied for HLA class II genes in a Mexican rural city (Santo Domingo Ocotitlan, Morelos State) belonging to the nowadays Náhuatl speaking areas in Mexico. The most frequent HLA class II alleles were typical Amerindian (HLA-DRB1*04:07, DQB1*03:01 DRB1*04:03 or DRB1*04:04) and also were some calculated extended haplotypes (HLA-DRB1*04:07-DQB1*03:02,DRB1*08:02-DQB1*04:02, or DRB1*10:01-DQB1*05:01 among others). When using HLA-DRB1 Neís genetic distances, our isolated Nahua population was found to be close to other Central America Amerindians like the ancient-established Mayans or Mixe.
View Article and Find Full Text PDFThe presence of cells with regulatory functions in patients with cancer is one of the mechanisms whereby the immune system cannot confront tumor growth. We sought to determine the prevalence of immunoregulatory T-cell subpopulations, expressing the latency TGFβ-associated peptide (LAP), in patients with gastric adenocarcinoma. T cells were enriched from blood or gastric tissue (tumoral, TT or tumor-free, TF) samples from 22 patients, 6 with early (EGC) and 16 with advanced gastric cancer (AGC).
View Article and Find Full Text PDFClassical HLA (Human Leukocyte Antigen) is the Major Histocompatibility Complex (MHC) in man. HLA genes and disease association has been studied at least since 1967 and no firm pathogenic mechanisms have been established yet. HLA-G immune modulation gene (and also -E and -F) are starting the same arduous way: statistics and allele association are the trending subjects with the same few results obtained by HLA classical genes, i.
View Article and Find Full Text PDFAzeri people are at present day mainly living in an area which comprises North (Azerbaijan) and South (Azeri Iran provinces) parts, living the biggest population in Azeri Iran provinces with about 17-20 million people. They were studied HLA-A, -B, -DRB1 and -DQB1 allele and extended haplotype frequencies in unrelated Iranian Tabriz Azeris from a rural area close to Tabriz City. The HLA extended haplotypes with highest frequencies are: 1) HLA- A*24:02-B*35:01-DRB1*11:01-DQB1*03:01, shared with Mediterraneans and southern Russians (Chuvash, which also show Mediterranean characters); and 2) HLA-A*01:02-B*08:01-DRB1*03:01-DQB1*02:01, found also in Chuvash and other Azeri samples from Tabriz.
View Article and Find Full Text PDFHLA-G is a non-classical HLA class I molecule with immunomodulatory properties. It was initially described at the maternal-fetal interface, and it was later found that this molecule was constitutively expressed on certain immuneprivileged tissues, such as cornea, endothelial and erythroid precursors, and thymus. The immunosuppressive effect of HLA-G is exerted through the interaction with its cognate receptors, expressed on immunocompetent cells, like ILT2, expressed on NK, B, T cells and APCs; ILT4, on APCs; KIR, found on the surface of NK cells; and finally, the co-receptor CD8.
View Article and Find Full Text PDFHLA-G is a non-classical class I HLA molecule that induces tolerance by acting on receptors of both innate and adaptive immune cells. When overexpressed in tumors, limits surveillance by the immune system. The gene shows several polymorphisms involved in mRNA and protein levels.
View Article and Find Full Text PDFWe have applied two PCR techniques, differential PCR (diffPCR) and qPCR for the identification of HER2 gene amplifications in genomic DNA of tumor and distal gastric samples from patients with gastric cancer. The diffPCR technique consists of the simultaneous amplification of the HER2 gene and a housekeeping gene by conventional PCR and the densitometric analysis of the bands obtained. We established a cut-off point based on the mean and standard deviation analyzing the DNA of 30 gastric tissues from patients undergoing non-cancer gastrectomy.
View Article and Find Full Text PDFTGF-β1 is involved in tumour growth. Four TGFB1 SNPs and TGF-β1 production by stimulated PBMC were determined in seventy-eight gastric adenocarcinoma patients. In addition, TGF-β1 levels were measured in the plasma of further thirty patients.
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