RESUMO
The Human Leukocyte Antigen G (HLA-G) is an immunoregulatory molecule with a critical role in pregnancy success. HLA-G alleles are associated with differential susceptibility to multiple conditions, including gestational problems, infectious diseases, and viral persistence. Of note, both herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) can impair HLA-G expression, interfering with HLA-G-associated immunoregulation. On the other hand, the impacts of HLA-G alleles on susceptibility to Herpesviridae infection is a neglected issue. Therefore, this study evaluated HLA-G allele frequencies and their associations with placental Herpesviridae infection in women from southern Brazil. Placenta samples were collected soon after delivery, and detection of viral DNA of HSV-1, HSV-2 and human cytomegalovirus (HCMV) was performed by polymerase chain reaction (PCR). A fragment of HLA-G (exons 2-4) was amplified by PCR, sequenced, and analyzed to allele determination. One hundred and seventy women had their alleles determined. Overall, 25 HLA-G alleles were found, distributed into 56 different genotypes. The most frequent alleles were G* 01:01:01 and G* 01:01:02, found in 37.9 % and 16.5 % of samples, respectively. Among the 170 women, 89 (52.4 %) tested positive for Herpesviridae DNA in the placenta, 55 (32.3 %) tested negative, 3 (1.8 %) were negative for HSV-1 and HSV-2 (with absent HCMV data), and 23 (13.5 %) were undetermined. The G* 01:01:01 allele was significantly associated with an increased risk of placental HSV-1 infection (p = 0.0151; OR=1.837; IC=1.108-3.045). This study describes new information concerning placental HLA-G alleles in women from southern Brazil and helps explain how genetic background can modify susceptibility to placental infections.
Assuntos
Herpes Simples , Herpesvirus Humano 1 , Gravidez , Feminino , Humanos , Herpesvirus Humano 1/genética , Alelos , Antígenos HLA-G/genética , Brasil/epidemiologia , Placenta , Herpesvirus Humano 2/genética , CitomegalovirusRESUMO
Transitional carcinoma (TC) is the most common neoplasm of the bladder (80%). The immune checkpoint (IC) Human leukocyte antigen G (HLA-G) expression has been demonstrated within numerous types of cancer and correlates with the degree of malignancy. This study aims for HLA-G expression in the bladder TC in a public hospital in Argentina linking its malignancy grade with the survival of the patients. We study thirty TC samples, in which we determine the invasion level and the HLA-G expression by immunohistochemistry. From all analyzed cases, 23 correspond to high-grade TC, of whom 91% presented HLA-G immunostaining and 83% compromised the muscularis propria layer of the bladder. Four patients in this group have not exceeded 5 years of survival. This data confirms that HLA-G expression in the bladder TC is associated with greater aggressiveness. Therefore, adding this immunostaining to the immunohistochemical panel used in the routine diagnosis of this neoplasm would be very useful.
Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Antígenos HLA-G , Bexiga Urinária/metabolismo , Bexiga Urinária/patologia , Argentina , Estadiamento de Neoplasias , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/patologia , Hospitais Públicos , PrognósticoRESUMO
RESUMEN El trasplante de órganos sólidos se ha considerado el fin último para algunas enfermedades crónicas en estadio terminal, sin embargo, las incompatibilidades del HLA entre el donante y el receptor pueden permitir que la alorespuesta se convierta en nociva para el órgano trasplantado, respuesta que puede ser tanto innata como adaptativa. Se ha identificado el HLA-G como una molécula natural inductora de tolerancia (28) principalmente en el embarazo y se considera una molécula del HLA clase I no clásico, sin embargo, comparte algunas características estructurales con el HLA clásico. Los genes HLA-G se caracterizan por tener un limitado polimorfismo y una distribución celular y tisular restringida al trofoblasto fetal y células del epitelio tímico entre otras. La búsqueda persistente de la tolerancia en los trasplantes de órganos ha permitido un estudio específico del HLA-G, como posibilidad terapéutica para aumentar la sobrevida tanto de los injertos como de los pacientes trasplantados, es por tal motivo que se realiza una revisión en dicha molécula para estimular la investigación y entendimiento de sus funciones.
ABSTRACT Solid organ transplantation has been considered the ultimate goal for some end-stage chronic diseases, however, HLA incompatibilities between the donor and the recipient may allow the alloresponse to become deleterious for the transplanted organ, a response that can be both innate and adaptive. HLA-G has been identified as a natural tolerance-inducing molecule (28) mainly in pregnancy and is considered a non-classical HLA class I molecule; however, it shares some structural characteristics with classic HLA. HLA-G genes are characterized by having a limited polymorphism and a cellular and tissue distribution restricted to the fetal trophoblast and thymic epithelial cells, among others. The persistent search for tolerance in organ transplants has allowed a specific study of HLA-G, as a therapeutic possibility to increase grafts and transplant patient's survival; for this reason we carried out a review ofthis molecule to stimulate research and understanding of its functions.
RESUMO
Chronic hepatitis C virus (HCV) infection induces liver damage and the HCV/Human Immunodeficiency Virus (HIV)-coinfection may further contribute to its progression. The HLA-G molecule inhibits innate and adaptive immunity and may be deleterious for chronically virus-infected cells. Thus we studied 204 HCV-mono-infected patients, 142 HCV/HIV-coinfected patients, 104 HIV-mono-infected patients and 163 healthy subjects. HLA-G liver expression was similarly induced in HCV and HCV/HIV specimens, increasing with advanced fibrosis and necroinflammatory activity, and with increased levels of liver function-related enzymes. Plasma soluble HLA-G (sHLA-G) levels were higher in HCV/HIV patients compared to HCV, HIV and to healthy individuals. sHLA-G continued to be higher in coinfected patients even after stratification of samples according to degree of liver fibrosis and necroinflammatory activity when compared to mono-infected patients. Some HLA-G gene haplotypes differentiated patient groups and presented few associations with liver and plasma HLA-G expression. HLA-G thus may help to distinguish patient groups.
Assuntos
Infecções por HIV/imunologia , Antígenos HLA-G/genética , Antígenos HLA-G/metabolismo , Hepatite C Crônica/imunologia , Fígado/metabolismo , Adulto , Coinfecção , Feminino , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , HIV-1/imunologia , Haplótipos/genética , Hepacivirus/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Estudos RetrospectivosRESUMO
Hematopoietic stem-cell transplantation is widely performed for the treatment of hematologic diseases and is increasingly being used for the experimental treatment of various autoimmune diseases. Despite the rapid evolution of this therapy, the mortality rate of patients undergoing this procedure is still high, mainly due to the development of graft versus host disease (GvHD). Even with the administration of immunosuppressive therapy, some patients manifest the chronic form of the disease. For these cases, infusion of mesenchymal stem cells (MSCs) was proposed as a therapeutic strategy, considering the immunosuppressive potential of these cells. This review describes the main results obtained in cell therapy with MSCs for the treatment of GvHD. Despite the encouraging results found, some points differed among the studies. Although the factors that influence the different results are uncertain, some investigators have suggested that variations in immunosuppressive molecules are responsible for these divergences. We highlight the key role of the HLA-G gene in modulating the immune response, and the importance of the polymorphisms and alleles of this gene associated with the outcome of the transplants. We suggest that the HLA-G gene and its polymorphisms be analyzed as a factor in selecting the MSCs to be used in treating GvHD, given its strong immunosuppressive role.
Assuntos
Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/terapia , Antígenos HLA-G/genética , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Polimorfismo Genético , Humanos , Terapia de ImunossupressãoRESUMO
Objective: This study evaluated human leucocyte antigen-G gene polymorphisms in patients with periodontitis and healthy controls.Material and methods: The insertion/deletion polymorphism of 14 bp and a single nucleotide polymorphism (SNP) C > G on the position +3142 of the 3' untranslated region of the gene were analyzed in chronic periodontitis (n = 62), aggressive periodontitis (n = 24) patients and healthy individuals (n = 47).Results: Considering the 14 bp insertion/deletion, a significant deviation from Hardy-Weinberg expectations in the chronic periodontitis group was observed, but not in the other groups. No significant deviations were observed in patients and control groups considering the +3142 C > G SNP. A significant increased frequency of homozygotes for the 14 bp deletion allele was observed in the chronic periodontitis group as compared to controls. This group also presented a higher frequency of the deletion allele, which was marginally not significant. Concerning this polymorphism, no significant differences were observed between the aggressive periodontitis and healthy control groups. In addition, no significant differences were seen amongst patients and controls when considering the +3142 C > G frequencies.Conclusion: No differences were found amongst patients and controls when considering the +3142 C > G SNP haplotypes frequencies, but a significant increased frequency of homozygotes for the 14 bp deletion allele was observed in chronic periodontitis patients compared to healthy controls, suggesting a susceptibility role of this polymorphism in the pathogenesis of this condition.
Assuntos
Periodontite Agressiva , Periodontite Crônica , Antígenos HLA-G , Polimorfismo de Nucleotídeo Único , Periodontite Agressiva/genética , Alelos , Estudos de Casos e Controles , Periodontite Crônica/genética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Antígenos HLA , Antígenos HLA-G/genética , HumanosRESUMO
Human leukocyte antigen-G (HLA-G) is a nonclassical Major Histocompatibility Complex (MHC) molecule with immunomodulatory function and restricted tissue expression. The genetic diversity of HLA-G has been extensively studied in several populations, however, the segment located upstream -1406 has not yet been evaluated. We characterized the nucleotide variation and haplotype structure of an extended distal region (-2635), all exons and the 3'UTR segment of HLA-G by next-generation sequencing (NGS) in a sample of 335 Brazilian individuals. We detected 29 variants at the HLA-G distal promoter region, arranged into 19 haplotypes, among which we identified sites that may influence transcription factor targeting. Although the variation pattern in the distal region resembled the one observed in the conventional promoter segment, molecular signature for balancing selection was observed in the promoter segment from -1406 to -1 (Tajima's Dâ¯=â¯2.315, Pâ¯=â¯0.017), but not in this distal segment (Dâ¯=â¯1.049, Pâ¯=â¯0.118). Furthermore, the ancestry composition of this Brazilian population sample was determined by the analysis of SNPforID 34-plex ancestry informative marker (AIM) SNP panel. The distribution of HLA-G haplotypes was ancestry-dependent, corroborating previous findings and emphasizing the importance of considering the ancestry information in association studies.
Assuntos
Variação Genética , Genética Populacional , Antígenos HLA-G/genética , Regiões 3' não Traduzidas , Brasil , Biologia Computacional/métodos , Etnicidade/genética , Regulação da Expressão Gênica , Antígenos HLA-G/imunologia , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Seleção Genética , Transcrição GênicaRESUMO
Human leukocyte antigen-G (HLA-G) presents inhibitory functions in immune cells and is located in a chromosomal region associated with systemic lupus erythematosus (SLE) susceptibility. Polymorphisms in 3' untranslated region (3'UTR) of HLA-G gene may influence protein expression. To date, no study analyzing HLA-G polymorphism and expression in childhood-onset systemic lupus erythematosus (cSLE) has been conducted. Therefore, we investigated the influence of HLA-G 3'UTR polymorphisms in 50 cSLE patients and 144 healthy controls. For the expression analysis, the control group included 26 healthy individuals. No significant difference in allele, genotype, and haplotype frequencies was observed between patients and control group. However, both the 14 bp deletion allele (odds ratio [OR] = 2.76, 95% confidence interval [CI] = 1.17-6.52, P = .028) and the 14 bp deletion-deletion genotype (OR = 8.00, 95% CI = 1.57-40.65, P = .006) showed an association with lupus nephritis. After Bonferroni correction, none P-value remained statistically significant. Regarding HLA-G expression, no significant difference was observed between plasma levels of cSLE patients (56.02 U/mL, interquartile range [IQR] = 37.54-75.41) and control group (49.2 U/mL, IQR = 27.84-154.4, P = .952). However, when the patients were stratified according to clinical manifestations, patients with hematological manifestations showed a lower plasma concentration of soluble HLA-G (sHLA-G) (47.08 U/mL, IQR = 34.15-61.56) than patients with no hematological manifestations (65.26 U/mL, IQR = 47.69-102.60, P = .013). These results suggest that HLA-G polymorphism has small effect on cSLE susceptibility and that sHLA-G may be involved in the pathogenesis of the disease.
Assuntos
Regiões 3' não Traduzidas , Sequência de Bases , Antígenos HLA-G/genética , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Deleção de Sequência , Adolescente , Idade de Início , Alelos , Estudos de Casos e Controles , Criança , Feminino , Expressão Gênica , Frequência do Gene , Antígenos HLA-G/sangue , Antígenos HLA-G/imunologia , Haplótipos , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Masculino , Projetos PilotoRESUMO
BACKGROUND: The main function of the HLA-G molecule in its membrane-bound and soluble forms is to inhibit the immune response by acting on CD4+ T cells, cytotoxic T cells, NK cells and dendritic cells. Lung cancer is a leading cause of death worldwide, and annual incidence is high in both women and men. Some studies have reported an increase of HLA-G serum levels in lung cancer, probably generated by tumor cells escaping the antitumor immune response. In this study the concentration of soluble HLA-G in bronchoalveolar lavage (BAL) in patients with primary and metastatic lung cancer was measured to determine its relation with tumor histological type and overall patient status according to the Karnofsky scale. METHODS: Thirty-one lung cancer patients were included. A tumor biopsy was obtained by bronchoscopy and the tumor type was determined by hematoxylin and eosin staining. BAL samples were obtained to measure soluble HLA-G concentrations in an ELISA sandwich assay. RESULTS: The average value of soluble HLA-G was 49.04ng/mL. No correlation between soluble HLA-G levels and age, gender or smoking was observed. A highly significant difference was observed in the levels of soluble HLA-G in BAL from patients with different histological types of lung cancer, especially in metastatic tumors. The Karnofsky index showed a significant and inverse correlation with soluble HLA-G levels in BAL. CONCLUSIONS: Soluble HLA-G protein is significantly associated with metastatic tumors and patients with lower Karnofsky index and may be useful as a prognostic marker in lung cancer.
Assuntos
Adenocarcinoma/imunologia , Biomarcadores Tumorais/análise , Líquido da Lavagem Broncoalveolar/química , Antígenos HLA-G/análise , Neoplasias Pulmonares/imunologia , Adenocarcinoma/química , Adenocarcinoma/patologia , Idoso , Carcinoma de Células Pequenas/química , Carcinoma de Células Pequenas/imunologia , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Avaliação de Estado de Karnofsky , Pulmão/química , Neoplasias Pulmonares/química , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Fumar/metabolismo , SolubilidadeRESUMO
This study aims to comprehensively analyze human leucocyte antigen (HLA)-G polymorphisms association with susceptibility to systemic lupus erythematosus (SLE) development and clinical manifestations. The HLA-G 5' upstream regulatory region (URR), 3' untranslated region (UTR) and a cytosine deletion at exon 3 (ΔC, HLA-G*0105N allele) were analyzed in 114 SLE patients and 128 healthy controls from North East Brazil. The +3003T>C (rs1707) C allele and the HG010101c extended HLA-G allele were significantly more frequent in SLE patients than healthy controls (+3003C allele frequency: 12% in SLE patients vs 6% in controls; odds ratio (OR), 2.10, 95% confidence interval (CI), 1.06-4.28, P = 0.026; HG010101c frequency: 11.8% in SLE patients and 6.3% in controls; OR, 2.14, 95% CI, 1.01-4.51, P = 0.046) and were associated with susceptibility for disease development. Other polymorphisms were associated with different clinical manifestations. Although HLA-G role in SLE disease is far from being elucidated yet, our association study results along with a systematic review and meta-analysis suggest that HLA-G might be able to slightly modulate the complex SLE phenotype (pooled OR, 1.14, 95% CI, 1.02-1.27, P = 0.021).
Assuntos
Antígenos HLA-G/genética , Lúpus Eritematoso Sistêmico/genética , Regiões 3' não Traduzidas/genética , Regiões 5' não Traduzidas/genética , Adulto , Alelos , Autoanticorpos/sangue , Brasil , Feminino , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA-G/fisiologia , Haplótipos/genética , Humanos , Mutação INDEL , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Avaliação de SintomasRESUMO
We analyzed the possible association between human leukocyte antigen-G (HLA-G) genetic variants, supposed to regulate HLA-G expression, and the susceptibility to develop rheumatoid arthritis (RA) as well as its clinical manifestations. The 5'upstream regulatory region (5'URR) and 3'untranslated region (3'UTR) regions of the HLA-G gene were screened in 127 RA patients and 128 controls: 10 5'URR and 3 3'UTR HLA-G polymorphisms as well as two haplotypes were associated with risk for RA development, while a polymorphism in the 5'URR showed an association with the degree of disease activity. These findings, although the number of cases analyzed is limited and the P-values are modest, indicate a possible association between HLA-G gene polymorphisms and susceptibility to develop RA disease and its severity.
Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Antígenos HLA-G/genética , Regiões 3' não Traduzidas/genética , Região 5'-Flanqueadora/genética , Idoso , Brasil , Análise Mutacional de DNA , Progressão da Doença , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , RiscoRESUMO
In this study, we sought to investigate the genetic influence of two HLA-G 3'-untranslated region (3'-UTR) polymorphisms - 14 bp (rs66554220) and +3142C>G (rs1063320) and their compounding haplotypes in susceptibility to rheumatoid arthritis (RA) in a two-region Brazilian study comprising of 539 patients and 489 controls. All subjects were polymerase chain reaction (PCR) genotyped for the referred polymorphisms and logistic regression models controlling for sex, city and age were performed. Homozygozity for the +3142G allele was associated with an increased risk of RA [odds ratio (OR) = 1.45, 95% confidence interval (CI) = 1.075-1.959, P(Bonf) = 0.030], whereas no association was observed for the 14 bp polymorphism. Haplotype comparisons between patients and controls showed a decreased frequency of the delC haplotype in patients (OR = 0.70, 95% CI = 0.521-0.946, P(Bonf) = 0.040), which remained significant in the rheumatoid factor (RF)-positive group (OR = 0.66, 95% CI = 0.482-0.900, P(Bonf) = 0.018), but not in the RF-negative group. These results corroborate the hypothesis of an involvement of HLA-G in the susceptibility of RA. The +3142G allele is associated with haplotype lineages that share high identity and are regarded as low producers. The presence of the G allele in homozygosis could be responsible for a low HLA-G expression profile that could favor the triggering of RA.