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INTRODUCTION: SARS-CoV-2 infection in Mexico has caused ~2.7 million confirmed cases; around 20%-25% of health workers will be infected by the virus at their workplace, with approximately 4.4% of mortality. High infectivity of SARS-CoV-2 is related with cell entry mechanism, through the ACE receptor. SARS-CoV-2 requires transmembrane protease serine 2 to cleave its spike glycoprotein and ensure fusion of host cell and virus membrane. We propose studying prophylactic treatment with hydroxychloroquine (HCQ) and bromhexine (BHH), which have been shown to be effective in preventing SARS-CoV-2 infection progression when administered in early stages. The aim of this study is to assess the efficacy of HCQ and BHH as prophylactic treatments for SARS-CoV-2 infection in healthy health workers exposed to the virus. METHODS AND ANALYSIS: Double-blind randomised clinical trial, with parallel allocation at a 1:1 ratio with placebo, of low doses of HCQ plus BHH, for 60 days. Study groups will be defined as follows: (1) HCQ 200 mg/day+BHH 8 mg/8 hours versus (2) HCQ placebo plus BHH placebo. Primary endpoint will be efficacy of both interventions for the prevention of SARS-CoV-2 infection, determined by the risk ratio of infected personnel and the absolute risk. At least a 16% reduction in absolute risk is expected between the intervention and placebo groups; a minimum of 20% infection is expected in the placebo group. The sample size calculation estimated a total of 214 patients assigned: two groups of 107 participants each. ETHICS AND DISSEMINATION: This protocol has been approved by the local Medical Ethics Committee (National Institute of Rehabilitation 'Luis Guillermo Ibarra Ibarra', approval number INRLGII/25/20) and by the Federal Commission for Protection against Sanitary Risks (COFEPRIS, approval number 203 300 410A0058/2020). The results of the study will be submitted for publication in peer-reviewed journals and disseminated through conferences. TRIAL REGISTRATION NUMBER: NCT04340349.
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Bromoexina , Tratamento Farmacológico da COVID-19 , Método Duplo-Cego , Humanos , Hidroxicloroquina/uso terapêutico , México , SARS-CoV-2 , Resultado do TratamentoRESUMO
[This corrects the article DOI: 10.1155/2019/6357256.].
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BACKGROUND: Complex meniscal lesions often require meniscectomy with favorable results in the short term but a high risk of early osteoarthritis subsequently. Partial meniscectomy treated with meniscal substitutes may delay articular cartilage degeneration. PURPOSE: To evaluate the status of articular cartilage by T2 mapping after meniscal substitution with polyurethane scaffolds enriched with mesenchymal stem cells (MSC) and comparison with acellular scaffolds at 12 months. METHODS: Seventeen patients (18-50 years) with past meniscectomies were enrolled in 2 groups: (1) acellular polyurethane scaffold (APS) or (2) polyurethane scaffold enriched with MSC (MPS). Patients in the MPS group received filgrastim to stimulate MSC production, and CD90+ cells were obtained and cultured in the polyurethane scaffold. The scaffolds were implanted arthroscopically into partial meniscus defects. Concomitant injuries (articular cartilage lesions or cartilage lesions) were treated during the same procedure. Changes in the quality of articular cartilage were evaluated with T2 mapping in femur and tibia at 12 months. RESULTS: In tibial T2 mapping, values for the MPS group increased slightly at 9 months but returned to initial values at 12 months (P > 0.05). In the APS group, a clear decrease from 3 months to 12 months was observed (P > 0.05). This difference tended to be significantly lower in the APS group compared with the MPS group at the final time point (P = 0.18). In the femur, a slight increase in the MPS group (47.8 ± 3.4) compared with the APS group (45.3 ± 4.9) was observed (P > 0.05). CONCLUSION: Meniscal substitution with polyurethane scaffold maintains normal T2 mapping values in adjacent cartilage at 12 months. The addition of MSC did not show any advantage in the protection of articular cartilage over acellular scaffolds (P > 0.05).
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Cartilagem Articular , Traumatismos do Joelho/cirurgia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Osteoartrite do Joelho , Poliuretanos/química , Lesões do Menisco Tibial/terapia , Alicerces Teciduais , Adolescente , Adulto , Cartilagem Articular/cirurgia , Cartilagem Articular/transplante , Feminino , Humanos , Masculino , Meniscectomia , Menisco/cirurgia , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Engenharia Tecidual , Resultado do Tratamento , Adulto JovemAssuntos
Anti-Inflamatórios/administração & dosagem , Antivirais/administração & dosagem , Tratamento Farmacológico da COVID-19 , Anti-Inflamatórios/farmacologia , Antivirais/farmacologia , COVID-19/virologia , Reposicionamento de Medicamentos , Quimioterapia Combinada , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: Human mesenchymal stem cells (hMSCs) are a promising source for regenerative medicine, especially mesodermal lineages. Clinical applications require an understanding of the mechanisms for transcriptional control to maintain the desired cell type. The aim of this study was to identify novel markers for differentiation of hMSCs into bone or cartilage with the use of Kartogenin, by RNA analysis using microarray technology, and explore the role of RhoA-Rho associated protein kinase (ROCK) inhibition in these. METHODS: Commercial human bone marrow derived primary mesenchymal stem cells were purchased from ATCC. Cells were differentiated in vitro in 2-dimensional cultures using Kartogenin as the main cartilage inducer and bone morphogenetic protein 2 for bone differentiation; cells were cultured with and without ROCK inhibitor Y-27632. After 21 days of culture, whole RNA was extracted and analyzed via Affimetrix microarrays. The most significant hits were validated by quantitative polymerase chain reaction. RESULTS: We found a total of 1,757 genes that were either up- or downregulated on differentiation, when compared to P1 hMSC (control) at day 0 of differentiation. Two members of the Serpin superfamily, SERPINA9 and SERPINB2, were significantly upregulated in the cartilage groups, whereas they were unchanged in the bone groups with and without ROCK inhibition. CONCLUSIONS: SERPINA9 and SERPINB2 are novel differentiation markers, and molecular regulator candidates for hMSC lineage commitment toward bone and cartilage, providing a new tool for regenerative medicine. Our study highlights the roles of these 2 genes, with significant upregulation of both in cell cultures stimulated with Kartogenin.
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Antígenos de Diferenciação/genética , Cartilagem/citologia , Linhagem da Célula/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células-Tronco Mesenquimais/citologia , Proteínas de Neoplasias/metabolismo , Serpinas/metabolismo , Anilidas , Proteína Morfogenética Óssea 2 , Diferenciação Celular/genética , Células Cultivadas , Humanos , Ácidos Ftálicos , RNA/isolamento & purificação , Regulação para Cima/genéticaRESUMO
Hyper-IgE syndrome (HIES) is a rare primary immunodeficiency characterized by elevated levels of immunoglobulin E (IgE), eczematous dermatitis, cold abscesses, and recurrent infections of the lung and skin caused by Staphylococcus aureus. The dominant form is characterized by nonimmunologic features including skeletal, connective tissue, and pulmonary abnormalities in addition to recurrent infections and eczema. Omalizumab is a humanized recombinant monoclonal antibody against IgE. Several studies reported clinical improvement with omalizumab in patients with severe atopic eczema with high serum IgE level. We present the case of a 37-year-old male with HIES and cutaneous manifestations, treated with humanized recombinant monoclonal antibodies efalizumab and omalizumab. After therapy for 4 years, we observed diminished eczema and serum IgE levels.
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BACKGROUND: Colostrum is the primary source of maternal immunoglobulin A (IgA) for the newborn. IgA participates in protection and regulation mechanisms of the immune response at the neonate's mucosa. Several studies have evaluated infectious diseases and vaccine protocols effects during pregnancy on maternal milk IgA levels, with the aim to understand lactation protecting effect on newborn. However, most of their results demonstrated that there were no differences in the total IgA levels. In humans, IgA has two subclasses (IgA1 and IgA2), they have an anatomical distribution among mucosal compartments, their levels vary after antigen stimulation and are also seen to describe differential affinities in colostrum. Although there are differences between IgA subclasses in several compartments, these studies have excluded specific colostrum IgA1 and IgA2 determination. METHODS: We analyzed data from 900 women in Mexico City. With Pearson correlation, we compared the number of infectious episodes during their pregnancy that was associated with mucosal compartments (skin, respiratory and gastrointestinal tracts) and colostrum IgA subclasses. RESULTS: We show a correlation between increased colostrum IgA1 levels and the number of infectious episodes at respiratory tract and the skin. In contrast, infections at the gastrointestinal tract correlated with increased IgA2 amounts. CONCLUSIONS: Infections present during pregnancy at certain mucosal site increase specific IgA subclasses levels in human colostrum. These results will help in understanding infections and immunizations effects on maternal IgA at the mammary gland, and their impact on the development and protection of the newborn.
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Purpose: The objective of this study was to determine whether a comorbidity index could be used to predict mortality in pediatric patients with chemotherapy-treated solid tumors. Methods: Pediatric patients who underwent chemotherapy treatment for solid tumors were included, and demographic, clinical, and comorbidity data were obtained from patient electronic records. Results: A total of 196 pediatric patients with embryonic solid tumors were included. Metastatic tumors were the most frequently observed (n = 103, 52.6%). The most common comorbidities encountered for the Charlson comorbidity index (CCI) were cellulitis (n = 24, 12.2%) and acute renal failure (n = 15, 7.7%). For the Pediatric Comorbidity Index (PCI), the most frequent comorbidities were pneumonia and sepsis, with n = 64 (32.7%) for each. We evaluated established the prognostic values for both indexes using Kaplan-Meier curves, finding that the CCI and PCI could predict mortality with p < 0.0001. Conclusion: Using the PCI, we observed 100% survival in patients without comorbidities, 70% survival in patients with a low degree of comorbidity, and 20% survival in patients with a high degree of comorbidity. Greater discrimination of probability of survival could be achieved using degrees of comorbidity on the PCI than using degrees of comorbidity on the CCI. The application of the PCI for assessing the hospitalized pediatric population may be of importance for improving clinical evaluation.
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OBJECTIVE: To evaluate cardiac function by conventional echocardiography and tissue Doppler imaging in fetuses with left congenital diaphragmatic hernia (CDH). METHODS: Conventional echocardiography (myocardial performance index, ventricular filling velocities, and E/A ratios) and tissue Doppler imaging (annular myocardial peak velocities, E/E' and E'/A' ratios) in mitral, septal, and tricuspid annulus were evaluated in a cohort of 31 left-sided CDH fetuses and compared with 75 controls matched for gestational age 2:1. RESULTS: In comparison to controls, CDH fetuses had prolonged isovolumetric time periods (isovolumetric contraction time 35 ms vs 28 ms, P < .001), with higher myocardial performance index (0.49 vs 0.42, P < .001) and tricuspid E/A ratios (0.77 vs 0.72, P = .033). Longitudinal function assessed by tissue Doppler showed signs of impaired relaxation (mitral lateral A' 8.0 vs 10.1 cm/s, P < .001 and an increased mitral lateral E'/A' ratio 0.93 vs 0.78, P < .001) in the CDH fetuses as compared with controls, with preserved systolic function. CONCLUSION: Left CDH fetuses show echocardiographic signs of diastolic dysfunction, probably secondary to fetal heart compression, maintaining a preserved systolic function.
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Coração Fetal/fisiopatologia , Hérnias Diafragmáticas Congênitas/fisiopatologia , Adulto , Estudos de Casos e Controles , Ecocardiografia , Feminino , Coração Fetal/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Humanos , Gravidez , Estudos Prospectivos , Ultrassonografia Pré-NatalRESUMO
Only select tissues and organs are able to spontaneously regenerate after disease or trauma, and this regenerative capacity diminishes over time. Human stem cell research explores therapeutic regenerative approaches to treat various conditions. Mesenchymal stem cells (MSCs) are derived from adult stem cells; they are multipotent and exert anti-inflammatory and immunomodulatory effects. They can differentiate into multiple cell types of the mesenchyme, for example, endothelial cells, osteoblasts, chondrocytes, fibroblasts, tenocytes, vascular smooth muscle cells, and sarcomere muscular cells. MSCs are easily obtained and can be cultivated and expanded in vitro; thus, they represent a promising and encouraging treatment approach in orthopedic surgery. Here, we review the application of MSCs to various orthopedic conditions, namely, orthopedic trauma; muscle injury; articular cartilage defects and osteoarthritis; meniscal injuries; bone disease; nerve, tendon, and ligament injuries; spinal cord injuries; intervertebral disc problems; pediatrics; and rotator cuff repair. The use of MSCs in orthopedics may transition the practice in the field from predominately surgical replacement and reconstruction to bioregeneration and prevention. However, additional research is necessary to explore the safety and effectiveness of MSC treatment in orthopedics, as well as applications in other medical specialties.
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[This corrects the article DOI: 10.1155/2016/1472567.].
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In the classification of primary immunodeficiencies, hyper-IgE syndrome, identified with OMIM code # 147060 in the Online Mendelian Inheritance in Man catalog, belongs to the group of syndromes associated with combined immunodeficiencies. It is characterized by elevated levels of IgE, eosinophilia, recurrent skin abscesses, pneumonia, lung parenchyma lesions, recurrent infections, rashes in newborns, eczema, sinusitis, otitis, and mucocutaneous candidiasis. Hyper-IgE syndrome can be transmitted by autosomal dominant or autosomal recessive modes of inheritance. Hyper-IgE syndrome in its dominant form includes non-immunological manifestations like characteristic facies, pathological dentition, scoliosis, bone disorders, and joint hyperextensibility. The reported cause of the dominant form is the loss of function of the signal transducer and activator of transcription 3 (STAT-3, with MIM # 102582). Mutations in dedicator of cytokines 8 (DOCK-8) is the most common cause of the autosomal recessive form of hyper-IgE syndrome.
En la Clasificación de las Inmunodeficiencias Primarias, el síndrome hiper-IgE, identificado con el código OMIM #147060 en el Catálogo Online Mendelian Inheritance in Man, pertenece al grupo de las inmunodeficiencias combinadas asociadas a síndromes. Se caracteriza por elevación de la concentración de IgE, eosinofilia, abscesos recurrentes en piel, neumonías, lesiones en parénquima pulmonar, infecciones recurrentes, erupciones en el recién nacido, eccema, sinusitis, otitis y candidiasis mucocutáneas. El síndrome hiper-IgE puede ser transmitido hereditariamente en forma autosómica dominante o autosómica recesiva. El síndrome hiper-IgE en su forma dominante incluye manifestaciones no inmunológicas como facies característica, dentición patológica, escoliosis, alteraciones óseas e hiperextensibilidad articular. La causa identificada en la forma dominante es la pérdida de la función del transductor de señales y activador de la transcripción 3 (STAT-3, MIM #102582). Las mutaciones en la proteína dedicada a la citocinesis 8 (DOCK-8) representan la mayoría de las causas de la forma autosómica recesiva del síndrome hiper-IgE.
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Fatores de Troca do Nucleotídeo Guanina/genética , Síndrome de Job/genética , Mutação , Fator de Transcrição STAT3/genética , Humanos , Síndromes de Imunodeficiência/classificação , Síndrome de Job/classificação , Síndrome de Job/complicaçõesRESUMO
Osteoarthritis is characterized by the presence of proinflammatory cytokines and reactive oxygen species. We aimed to clarify the role of prooxidant enzyme content at the synovial membrane level and how it correlates with the inflammatory process in patients with knee osteoarthritis (KOA). In synovial membranes from KOA patients and control group, we analyzed the protein content of prooxidant enzymes such as Nox2, xanthine oxidase (XO), and prolidase as well as the proinflammatory NALP3. Results show that protein content of prolidase and Nox2 increased 4.8- and 8.4-fold, respectively, and XO showed an increasing trend, while the NALP3 inflammasome increased 5.4-fold with respect to control group. Levels of prolidase and XO had a positive correlation between the levels of NALP3 and Nox2. By principal component analysis the protein expression pattern by study groups was evaluated. Three clusters were identified; protein expression patterns were higher for clusters two (prolidase) and three (XO and Nox2) between KOA patients and controls. Data suggest that prooxidant enzymes increase in synovial membrane of KOA patients and may contribute to the inflammatory state and degradation of the articular cartilage.
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Dipeptidases/metabolismo , Inflamassomos/metabolismo , Glicoproteínas de Membrana/metabolismo , NADPH Oxidases/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Osteoartrite do Joelho/patologia , Membrana Sinovial/metabolismo , Adulto , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Análise por Conglomerados , Citocinas/metabolismo , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , NADPH Oxidase 2 , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Osteoartrite do Joelho/metabolismo , Análise de Componente Principal , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos , Xantina Oxidase/metabolismoRESUMO
Hyper IgE syndrome (HIES) is characterized by recurrent skin abscesses, eczema, pneumonia, and high levels of serum IgE. Nonimmunologic manifestations of HIES include a characteristic face, pathologic dentition, scoliosis, bone alterations, hyperextensible joints, and vascular abnormalities. Somatic mosaicism is defined by the presence of two or more populations of cells with different genotypes in one individual. In this report, we describe one patient with classical HIES and another patient with a mild phenotype, both harboring the same genetic mutation. The patient with a mild phenotype did not present the characteristic face, had normal production of IL-17A by T CD4+ cells, but had low phosphorylation of STAT-3 in B cells. Interestingly, the mutation found in B cells was absent in other cell types analyzed, in agreement with the presence of a somatic mosaic genotype. The clinical and functional differences observed between these patients justify the use of complementary tools for a better definition of the cases. These approaches allow for a better understanding of complex phenotypes associated with somatic mosaicisms, and present the possibility to analyze the role of B lymphocytes in the pathophysiology of this disease. This knowledge has an impact on not only the treatment but also the provision of appropriate genetic counseling.
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Linfócitos B/fisiologia , Síndrome de Job/imunologia , Mosaicismo , Mutação/genética , Fator de Transcrição STAT3/genética , Células Th17/fisiologia , Adulto , Células Cultivadas , Feminino , Aconselhamento Genético , Genótipo , Humanos , Imunoglobulina E/metabolismo , Memória Imunológica , Interleucina-17/metabolismo , Síndrome de Job/diagnóstico , Masculino , Especificidade de Órgãos , Fenótipo , Fosforilação/genética , Fator de Transcrição STAT3/metabolismo , Adulto JovemRESUMO
Signal transducer and activator of transcription 3 (STAT3) deficiency is a primary immunodeficiency characterized by eczema, complicated recurrent infections, elevated serum immunoglobulin E (IgE), osteopenia, and minimal trauma fractures. Zoledronic acid (ZA) is a long-acting bisphosphonate that has been successfully used in children with secondary osteoporosis and osteogenesis imperfecta. We describe the case of a 7-year-old male with STAT3 deficiency and minimal trauma fractures, who also developed osteonecrosis of the hip. He responded well to intravenous ZA every 6 months for 18 months. Three years later, he walks independently and unaided, and has not suffered any other fractures. Although more studies are needed, ZA might help reduce minimal trauma fractures in patients with STAT3 deficiency.
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Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Fraturas Ósseas/tratamento farmacológico , Quadril/patologia , Imidazóis/uso terapêutico , Osteonecrose/tratamento farmacológico , Fator de Transcrição STAT3/deficiência , Criança , Fraturas Ósseas/etiologia , Humanos , Masculino , Ácido ZoledrônicoRESUMO
Mobilized peripheral blood (MPB) bone marrow cells possess the potential to differentiate into a variety of mesenchymal tissue types and offer a source of easy access for obtaining stem cells for the development of experimental models with applications in tissue engineering. In the present work, we aimed to isolate by magnetic activated cell sorting CD90+ cells from MPB by means of the administration of Granulocyte-Colony Stimulating Factor and to evaluate cell proliferation capacity, after thawing of the in vitro culture of this population of mesenchymal stem cells (MSCs) in sheep. We obtained a median of 8.2 ± 0.6 million of CD90+ cells from the 20-mL MPB sample. After thawing, at day 15 under in vitro culture, the mean CD90+ cells determined by flow cytometry was 92.92 ± 1.29 % and cell duplication time determined by crystal violet staining was 47.59 h. This study describes for the first time the isolation, characterization, and post-in vitro culture thawing of CD90+ MSCs from mobilized peripheral blood in sheep. This population can be considered as a source of MSCs for experimental models in tissue engineering research.
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Criopreservação/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco de Sangue Periférico/citologia , Antígenos Thy-1/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Separação Celular , Forma Celular , Citometria de Fluxo , Imunofluorescência , Imunofenotipagem , Masculino , OvinosRESUMO
NF-κB essential modulator (NEMO) is a component of the IKK complex, which participates in the activation of the NF-κB pathway. Hypomorphic mutations in the IKBKG gene result in different forms of anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID) in males without affecting carrier females. Here, we describe a hypomorphic and missense mutation, designated c.916G>A (p.D306N), which affects our patient, his mother, and his sister. This mutation did not affect NEMO expression; however, an immunoprecipitation assay revealed reduced ubiquitylation upon CD40-stimulation in the patient's cells. Functional studies have demonstrated reduced phosphorylation and degradation of IκBα, affecting NF-κB recruitment into the nucleus. The patient presented with clinical features of ectodermal dysplasia, immunodeficiency, and immune thrombocytopenic purpura, the latter of which has not been previously reported in a patient with NEMO deficiency. His mother and sister displayed incontinentia pigmenti indicating that, in addition to amorphic mutations, hypomorphic mutations in NEMO can affect females.
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Displasia Ectodérmica/genética , Família , Quinase I-kappa B/genética , Síndromes de Imunodeficiência/genética , Incontinência Pigmentar/genética , Púrpura Trombocitopênica Idiopática/genética , Ubiquitinação/genética , Adolescente , Adulto , Displasia Ectodérmica/imunologia , Feminino , Heterozigoto , Humanos , Quinase I-kappa B/imunologia , Síndromes de Imunodeficiência/imunologia , Incontinência Pigmentar/imunologia , Masculino , Mutação de Sentido Incorreto , Púrpura Trombocitopênica Idiopática/imunologia , Ubiquitinação/imunologiaRESUMO
Hodgkin lymphoma (HL) is a rare neoplasm of the lymphatic system, in which inflammation and allelic variants in cytokines have been proposed as etiological factors. Epstein-Barr virus infection is often associated as a risk factor in HL and since cytokines are involved in the humoral response to viral infection. Our aim was to study the association between single nucleotide polymorphisms (SNPs) located in the tumor necrosis factor (TNF) gene (- 376G> A, - 238G> A and 581G> A) in a sample of Mexican patients (56 cases) and their susceptibility to develop HL, comparing these SNPs among healthy individuals (127 controls). Frequencies for TNF - 238G> A and TNF 581G> A showed no significant differences between cases and controls. However, the proportion of cases with the GA genotype of - 376 SNP showed a significant difference as compared to controls, odds ratio = 4.41 (95% confidence interval: 1.21-16.6), p = 0.02. We found that in this group of patients from Mexico the SNP - 376G> A in TNF shows an association with higher risk for HL.
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Predisposição Genética para Doença , Doença de Hodgkin/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/epidemiologia , Humanos , Masculino , México , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Polimorfismo de Nucleotídeo Único , Adulto JovemRESUMO
Major histocompatibility complex (MHC) genes are highly polymorphic and informative in disease association, transplantation, and population genetics studies with particular importance in the understanding of human population diversity and evolution. The aim of this study was to describe the HLA diversity in Mexican admixed individuals. We studied the polymorphism of MHC class I (HLA-A, -B, -C), and class II (HLA-DRB1, -DQB1) genes using high-resolution sequence based typing (SBT) method and we structured the blocks and conserved extended haplotypes (CEHs) in 234 non-related admixed Mexican individuals (468 haplotypes) by a maximum likelihood method. We found that HLA blocks and CEHs are primarily from Amerindian and Caucasian origin, with smaller participation of African and recent Asian ancestry, demonstrating a great diversity of HLA blocks and CEHs in Mexicans from the central area of Mexico. We also analyzed the degree of admixture in this group using short tandem repeats (STRs) and HLA-B that correlated with the frequency of most probable ancestral HLA-C/-B and -DRB1/-DQB1 blocks and CEHs. Our results contribute to the analysis of the diversity and ancestral contribution of HLA class I and HLA class II alleles and haplotypes of Mexican admixed individuals from Mexico City. This work will help as a reference to improve future studies in Mexicans regarding allotransplantation, immune responses and disease associations.
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Pool Gênico , Variação Genética , Haplótipos/genética , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Adulto , Alelos , Sequência Conservada/genética , Feminino , Frequência do Gene/genética , Genética Populacional , Humanos , Masculino , México , Análise de Componente Principal , População Branca/genéticaRESUMO
Intravenous drug use has become the principal route of hepatitis C virus (HCV) transmission due to the sharing of infected needles. In this study, we analyzed the distribution of HLA-KIR genotypes among 160 Puerto Rican intravenous drug users (IDUs) with HCV infection and 92 HCV-negative Puerto Rican IDUs. We found a significant association between the presence of different combinations of KIR inhibitory receptor genes (KIR2DL2 and/or KIR2DL3, pC=0.01, OR=0.07; KIR2DL2 and/or KIR2DL3+KIR2DS4, pC=0.01, OR=0.39) and HLA-C1 homozygous genotypes (HLA-C1+KIR2DS4, pC=0.02, OR=0.43; HLA-C1+KIR2DL2+KIR2DS4, pC=0.02, OR=0.40) together with the activating receptor KIR2DS4 (HLA-C1+KIR2DS4+KIR2DL3 and/or KIR2DL2, pC=0.004, OR=0.38) with protection from HCV infection. Our findings in HCV-infected and non-infected IDUs suggest an important role for KIRs (KIR2DL2 and KIR2DL3) with group HLA-C1 molecules, in the presence of activating KIR2DS4, in protection from HCV infection. These results support the hypothesis that activator signaling, mediated by KIR2DS4, plays a determinant role in the regulation of NK cell antiviral-activity.