Conceptos básicos en inmunología de la reproducción: revisión narrativa de la bibliografía / Basic concepts in reproductive immunology: a narrative review of the literature

Resumen: ANTECEDENTES: La inmunología de la reproducción no es un área nueva: siempre ha estado relacionada con el aborto recurrente y con la falla repetida en la implantación, sobre todo en el contexto de una fertilización in vitro. Recientemente emergieron nuevos conceptos importantes que los ginecoobstetras deben considerar. OBJETIVO: Interrelacionar los conceptos básicos de inmunología, embriología y reproducción asistida para comprender mejor lo que la primera puede resolver y lo que no. METODOLOGÍA: Estudio retrospectivo efectuado con base en la búsqueda electrónica, llevada a cabo en febrero de 2020 en las bases de datos: PubMed y Google Scholar con los siguientes términos (MeSH): abortion, spontaneous/immunology; embryo implantation/immunology; HLA-c antigens/immunology; immune tolerance/immunology; immunity, maternally-acquired/immunology; uterus/immunology; killer cells, natural/immunology; placentation/immunology; receptors, kir/immunology; antigen presentation/genetics; antigen presentation/immunology; maternal-fetal exchange/genetics; maternal-fetal exchange/immunology. RESULTADOS: Se reunieron 289 artículos y se eliminaron 248 por no cumplir con los criterios de inclusión; solo se analizaron 41. Los artículos identificados sirvieron de base para actualizar la situación de la inmunología en el contexto de la medicina de la reproducción. Durante el proceso se revisaron otros artículos que sirvieran de soporte bibliográfico a los conceptos descritos en esta revisión. CONCLUSIONES: Debido al destacado interés en el estudio de la genética de los embriones, la medicina de la reproducción se enfocó más en ella y dejó de lado a la inmunología. Sin embargo, como la genética sigue sin poder explicar de manera adecuada las fallas en la implantación, la inmunología de la reproducción vuelve a cobrar impulso.

Abstract: BACKGROUND: Reproductive immunology is not a new area in reproductive medicine, it has always been related to recurrent miscarriage and repeated implantation failure, especially in the context of IVF. Recently, new concepts have emerged that are important for OBGYN specialists to keep in mind. OBJECTIVE: Interrelating the basic concepts of immunology, embryology and assisted reproduction to better understand what the former can and cannot solve. METHODOLOGY: Retrospective study based on the electronic search, carried out in February 2020, in the databases: PubMed and Google Scholar with the following terms (MeSH) The following MeSH terms were used: Abortion, Spontaneous/immunology; Embryo Implantation/immunology; HLA-C Antigens/immunology; Immune Tolerance/immunology; Immunity, Maternally-Acquired/immunology; Uterus/immunology; Killer Cells, Natural/immunology; Placentation/immunology; Receptors, KIR/immunology; Antigen Presentation/genetics; Antigen Presentation/immunology; Maternal-Fetal Exchange/genetics; Maternal-Fetal Exchange/immunology. RESULTS: 289 articles were collected, and 248 articles were deleted because they did not meet the inclusion criteria; only 41 were analyzed. The articles identified served as a basis for updating the status of immunology in the context of reproductive medicine. During the process, other articles were reviewed to serve as bibliographic support for the concepts described in this review. CONCLUSIONS: Due to the outstanding interest in the study of embryo genetics, reproductive medicine focused more on it and left immunology aside. However, since genetics still cannot adequately explain implantation failures, reproductive immunology is gaining momentum again.

The role of KIR2DL3/HLA-C*0802 in Brazilian patients with rheumatoid vasculitis

OBJECTIVES: Rheumatoid arthritis is a polygenically controlled systemic autoimmune disease. Rheumatoid vasculitis is an important extra-articular phenotype of rheumatoid arthritis that can result in deep cutaneous ulcers. The objective of this study was to establish a correlation between the frequency of major histocompatibility complex class I/II alleles and killer immunoglobulin-like receptor genotypes in patients with cutaneous rheumatoid vasculitis. METHODS: Using the Scott & Bacon 1984 criteria to diagnose rheumatoid vasculitis and after excluding any other causes such as diabetes, atherosclerosis, adverse drug reactions, infection, and smoking, patients who met the criteria were selected. All of the selected rheumatoid vasculitis patients presented deep cutaneous ulcers. Identification of the major histocompatibility complex class I/II and killer immunoglobulin-like receptor genotypes was performed by polymerase chain reaction assays of samples collected from the 23 rheumatoid vasculitis patients as well as from 80 controls (40 non-rheumatoid vasculitis RA control patients and 40 healthy volunteers). RESULTS: An association between the presence of the HLA-DRB1*1402 and HLA-DRB1*0101 alleles and cutaneous lesions in rheumatoid vasculitis patients and a correlation between the inhibitor KIR2DL3 and the HLA-C*0802 ligand in rheumatoid vasculitis patients were found. CONCLUSION: An association was found between the presence of the HLA-DRB1*1402 and HLA-DRB1*0101 alleles and the development of cutaneous lesions in rheumatoid vasculitis patients. Additionally, the HLA-C*0802 ligand protects these individuals from developing cutaneous lesions. .

The genetic study on a rare inter-allelic recombination of HLA-C locus in a Chinese Han family / 中华检验医学杂志

Objective To study the inter-allelic recombination event occurring in the HLA-C locus in a family of Chinese Han nationality, and to evaluate the molecular genetic background of the new HLA allele.Methods Peripheral blood samples were collected from a Chinese leukemia woman patient, as well as her healthy parents and two brothers.HLA-A, C, B, DRB1 and DQB1 alleles were typed by high-resolution PCR-sequence-based typing (SBT) method using Atria Genetic AlleleSEQR HLA SBT kits.The Protrans S4 HLA-C single allele-specific sequencing strategy was used to separate the two HLA-C alleles and to determine novelty of the allele.The full length sequences of HLA-C alleles of the patient and her parents were further analyzed using cloning and haplotype sequencing method. The HLA five loci linked haplotypes and the recombination site were analyzed by family study, meanwhile the full length sequences of the five HLA-C alleles were compared with the IMGT/HLA database by the program BLAST.Results The two haplotypes of the father and mother were a:A*0207-C*010201-B*550201-DRB1*090102-DRQ1*030302 and b:A*240201-C*120202-B*5201-DRB1*1502-DRQ1*0601, c:A*300101-C*060201-B*130201-DRB1*0405-DRQ1*0401 and d:A*110101-C*070201-B*4001-DRB1*080302-DRQ1*0601,respectively.The two brothers inherited their parent′s haplotypes a, d and b, c respectively.The two haplotypes of the patient were the maternal c and paternal recombinant a/b haplotype.The recombinant a/b haplotype A*240201-C*new-B*550201-DRB1*090102-DRQ1*030302, A*240201 came from the paternal haplotype b,while B*550201-DRB1*090102-DRQ1*030302 came from the other paternal haplotype a.When comparing the full length sequences of the HLA-C new allele with the father′s allele C*010201 and C*120202, it could deduce that the recombinant a/b haplotype derived from a recombination event occurring between the paternal chromosome 6 during meiosis.The crossover site was between genomic nt273 and nt330 of HLA-C alleles, which created a HLA-C new allele and the fifth haplotype of the family, and inherited it to the patient.The full length sequences of the new allele had been submitted to Genbank, and officially named C*0121 by WHO nomenclature committee.Conclusion This study demonstrates a rare inter-allelic recombination event occurring in the HLA-C locus within a Chinese Han family and illustrates the process of novel allele and haplotype, and provides direct theory for further studying the mechanisms of gene recombination and HLA polymorphism.

Sequencing analysis of exons 1,5, 6, 7 of HLA-Cw gene located outside of the routine testing region and its application in clinical matching / 中华检验医学杂志

Objective To study the molecular genetic polymorphism of exons 1,5, 6, 7 of HLA-C gene in Chinese population and evaluate the significance of additional sequencing based typing at exons 1,5, 6, 7 of HLA-Cw gene in clinical HLA matching, Methods A total of 324 individuals were typed at exons 2,3, 4 of HLA-C gene by sequence-based typing. If ambiguities appeared outside of exons 2 -4, we designed a total of 5 in-house sequencing primers and optimized the sequencing reaction, additional sequencing based typing at exons 1,5, 6, 7 was performed to solove the emerging ambiguities. Results In the three hundred and twenty-four samples typed by PCR-SBT at exons 2, 3 and 4 of HLA-Cw gene, 23.8 % (77/324) of the typed samples were assigned the conclusive genotype in four digital level 76. 2% (247/324) of the typed samples were given with the ambiguous allele combination results, in which 73 kinds of ambiguous allele combinations were detected. Increasing the additional sequencing analysis at exons 1, 5, 6, 7 of HIA-C gene, ten frequent ambiguities including Cw* 030201/030202, Cw* 070201/0750, Cw* 040101/0409N/0430, Cw* 0403/0409N/0430, Cw* 080101/0822 could be distinguished. ConclusionsIncreasing the sequencing anlysis at exons 1, 5, 6 and 7 of HLA-Cw gene will help to make clear the ambiguous SBT results and also improve the accuracy of HLA-Cw typing. It shows important significance in clinical histoeompatibility matching.

Analysis of hlgh-resolution human leukocyte antigen matching status for the unrelated donor-receipt pairs matched at low-resolution for HLA-A, HLA-B and HLA-DRB1 / 中华检验医学杂志

le full matching for unrelated donor-receipt pairs. However, HLA-Cw mismatching at antigen level could no longer be ignored. The results indieated that HLA-Cw genotyping should be incorporated into future CMDP unrelated marrow donor routine HLA test.