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The Organ Procurement and Transplantation Network (OPTN) Kidney Allocation System provides a priority to sensitized candidates based on the calculated panel reactive antibody (CPRA) value. The human leukocyte antigen (HLA) haplotype reference panel used for calculation of the CPRA by the United Network for Organ Sharing (UNOS), the OPTN contractor, has limitations. We derived a novel panel from the National Marrow Donor Program HLA haplotype data set and compared the accuracy of CPRA values generated with this panel (NMDP-CPRA) to those generated from the UNOS panel (UNOS-CPRA), using predicted and actual deceased donor kidney offers for a cohort of 24 282 candidates. The overall accuracy for kidney offers was similar using NMDP-CPRA and UNOS-CPRA. Accuracy was slightly higher for NMDP-CPRA than UNOS-CPRA for candidates in several highly sensitized CPRA categories, with deviations in linkage disequilibrium for Caucasians and the smaller size of the UNOS panel as contributing factors. HLA data derived from stem cell donors yields CPRA values that are comparable to those derived from deceased kidney donors while improving upon several problems with the current reference panel. Consideration should be given to using stem cell donors as the reference panel for calculation of CPRA to improve equity in kidney transplant allocation.
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Isoanticorpos , Obtenção de Tecidos e Órgãos , Antígenos HLA , Teste de Histocompatibilidade , Humanos , Rim , Células-Tronco , Doadores de TecidosRESUMO
BACKGROUND & OBJECTIVES: : Celiac disease (CD) can exist in various forms in type 1 diabetes (T1D) patients and can remain undetected, leading to severe complications. This study was aimed to evaluate five commercially available anti-tissue transglutaminase (tTG) ELISA kits with distinct formats for the detection of CD and potential CD in T1D patients. Clinical and demographic profiles of the patients with different disease subsets were also studied. METHODS: : Fifty T1D patients with classical and non-classical symptoms of CD and 100 T1D patients without any symptoms of CD were included in this study. Anti-tTG autoantibody levels were estimated by five ELISA kits followed by histological examination of duodenal biopsy. HLA DQ2-DQ8 and DRB1-DQB1 typing was done, and serum levels for transforming growth factor (TGF)-ß1 were also estimated. RESULTS: : Assay format detecting anti-tTG IgA antibodies against recombinant antigens along with neopeptides of gliadin was most efficient in the detection of CD in symptomatic patients, and assay format detecting IgA+IgG helped in the detection of potential CD in asymptomatic T1D patients. These findings were supported by histological examination and human leucocyte antigen analysis. Patients with potential CD were found to have markedly deranged glycaemic control parameters and also had significantly raised serum levels of TGF-ß1, (P <0.05) compared to T1D patients. INTERPRETATION & CONCLUSIONS: : Potential CD can be frequently seen in T1D patients. This can be attributed to the dietary patterns prevalent in the subcontinent and the genetic basis of the disease. Anti-tTG IgA+IgG antibodies can be useful in the detection of these potential CD cases in T1D patients. Early intervention with gluten-free diet can be considered in these patients for better disease management.
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Doença Celíaca/sangue , Diabetes Mellitus Tipo 1/sangue , Transglutaminases/isolamento & purificação , Adolescente , Adulto , Anticorpos Anti-Idiotípicos/imunologia , Autoanticorpos/imunologia , Doença Celíaca/complicações , Doença Celíaca/dietoterapia , Doença Celíaca/imunologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 1/imunologia , Dieta Livre de Glúten , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta1/sangue , Transglutaminases/imunologia , Adulto JovemRESUMO
BACKGROUND: A complex interplay between genetic and environmental factors contributes to disease etiology of most of the autoimmune disorders. Type 1 diabetes mellitus (T1DM) and celiac disease (CD) are polygenic autoimmune diseases that have high propensity to coexist due to shared etiological factors like genetics and clinico-pathological overlaps. SUMMARY: The mean prevalence rate for coexistence of these diseases is 8%, and this value is a gross underestimation as reported from biopsy-proven symptomatic cases. The prevalence rate will rise when studies will excavate bottom layers of the "celiac iceberg" to detect potential and silent celiac cases. The concomitant presence of both these disorders is a complex situation immunologically as well as clinically. There is an accentuated breakdown of tolerance and proinflammatory cytokine storm that leads to the progression of organ-specific autoimmunity to systemic. No immunomodulating drugs are advocated as exogenous insulin supplementation and gluten exclusion are recommended for T1DM and CD respectively. Nevertheless, these pose certain challenges to both the clinicians and the patients, as gluten free diet (GFD) has been described to have an impact on glycemic control, bone health, and vascular complications. Also intermittent gluten intake by these patients due to non-compliance with GFD also stimulates the autoreactive immune cells that result in an augmented immune response. Key Messages: Large public health studies are needed to estimate the prevalence of all forms of CD in T1DM patients. Strict global guidelines need to be formulated for the disease management and prognosis, and there is also a need for an extensive research on each front to thoroughly understand the co-occurrence of these diseases.
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Doença Celíaca/complicações , Doença Celíaca/terapia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/terapia , Doença Celíaca/epidemiologia , Doença Celíaca/genética , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Humanos , Resultado do TratamentoRESUMO
Background: Immunosuppression therapy (IST) is required for allograft survival but can cause significant adverse effects. Donor-derived cell-free DNA (dd-cfDNA) is a validated noninvasive biomarker for active rejection in kidney transplant (KTx). Evidence supporting dd-cfDNA testing use in IST management is limited. Methods: In this single-center observational study, dd-cfDNA testing was performed in 21 KTx patients considered good candidates for mycophenolic acid (MPA) reduction. Patients with dd-cfDNA <1% at the first visit (enrollment) had their MPA dosage reduced; those with dd-cfDNA ≥1% had their MPA dosage maintained. Patients were monitored with dd-cfDNA for 6 additional visits. Results: Of 21 patients enrolled in the study, 17 were considered low risk for rejection by dd-cfDNA and underwent MPA reduction; 4 patients were considered high risk for rejection by dd-cfDNA and had their initial MPA dosage maintained. Of the 4 patients considered high risk for rejection by dd-cfDNA, 1 experienced chronic allograft nephropathy and graft loss, and another received an indication biopsy that showed no evidence of rejection. Of the 17 patients considered low risk for rejection by dd-cfDNA, none experienced allograft rejection. dd-cfDNA was used for surveillance in a 6-mo period following MPA reduction; no untoward results were noted. Conclusions: This proof-of-concept study reports the use of dd-cfDNA to directly inform IST management in a cohort of KTx who were candidates for IST reduction.
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AIM: This study was undertaken to explicate the shared and distinctive genetic susceptibility and immune dysfunction in patients with T1D alone and T1D with CD (T1D + CD). METHODS: A total of 100 T1D, 50 T1D + CD and 150 healthy controls were recruited. HLA-DRB1/DQB1 alleles were determined by PCR-sequence-specific primer method, SNP genotyping for CTLA-4 and PTPN22 was done by simple probe-based SNP-array and genotyping for INS-23 Hph1 A/T was done by RFLP. Autoantibodies and cytokine estimation was done by ELISA. Immune-regulation was analysed by flow-cytometry. Clustering of autoantigen epitopes was done by epitope cluster analytical tool. RESULTS: Both T1D alone and T1D + CD had a shared association of DRB1*03:01, DRB1*04, DRB3*01:07/15 and DQB1*02. DRB3*01:07/15 confers the highest risk for T1D with relative risk of 11.32 (5.74-22.31). Non-HLA gene polymorphisms PTPN22 and INS could discriminate between T1D and T1D + CD. T1D + CD have significantly higher titers of autoantibodies, expression of costimulatory molecules on CD4 and CD8 cells, and cytokine IL-17A and TGF-ß1 levels compared to T1D patients. Epitopes from immunodominant regions of autoantigens of T1D and CD clustered together with 40% homology. CONCLUSION: Same HLA genes provide susceptibility for both T1D and CD. Non-HLA genes CTLA4, PTPN22 and INS provide further susceptibility while different polymorphisms in PTPN22 and INS can discriminate between T1D and T1D + CD. Epitope homology between autoantigens of two diseases further encourages the two diseases to occur together. The T1D + CD being more common in females along with co-existence of thyroid autoimmunity, and have more immune dysregulated state than T1D alone.
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Autoantígenos , Doença Celíaca , Diabetes Mellitus Tipo 1 , Predisposição Genética para Doença , Proteína Tirosina Fosfatase não Receptora Tipo 22 , Humanos , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Índia/epidemiologia , Doença Celíaca/genética , Doença Celíaca/imunologia , Feminino , Masculino , Autoantígenos/imunologia , Autoantígenos/genética , Criança , Adolescente , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Adulto , Cadeias beta de HLA-DQ/genética , Autoanticorpos/imunologia , Autoanticorpos/sangue , Cadeias HLA-DRB1/genética , Adulto Jovem , Polimorfismo de Nucleotídeo Único , Pré-Escolar , Antígeno CTLA-4/genética , Genótipo , Estudos de Casos e ControlesRESUMO
BACKGROUND: Standard-of-care biomarkers for renal allograft rejection are lagging indicators, signaling existing organ injury. This precludes early intervention, when immunological cascades leading to rejection are most susceptible. Donor-derived cell-free DNA (dd-cfDNA) shows promise as an early indicator of rejection, allowing earlier and possibly more effective treatment. This analysis was designed to assess this promise using real-world dd-cfDNA testing evidence. METHODS: This retrospective analysis of the prospective, observational ProActive registry study (NCT04091984) assessed dd-cfDNA and serum creatinine levels before biopsy in 424 patients with ≥1 dd-cfDNA test (nâ =â 1013) in the 6 mo before biopsy. RESULTS: Of 4667 enrolled patients, 1631 patients had ≥18 mo of follow-up data, of which 424 had a biopsy and were included in this analysis. Twenty-six biopsies showed antibody-mediated rejection (ABMR), 62 showed T cell-mediated rejection, and 336 showed nonrejection; each from a unique patient. dd-cfDNA fractions were significantly elevated 5 mo before ABMR biopsies, and 2 mo before T cell-mediated rejection biopsies, compared with nonrejection biopsies. In contrast, serum creatinine did not discriminate between rejection and nonrejection in advance, or concurrent with biopsy. Among patients with nonrejection biopsies, estimated glomerular filtration rate was significantly lower in cases with ≥2 increased dd-cfDNA results (≥1%), compared with those with 0 or 1 increased dd-cfDNA result. CONCLUSIONS: These data indicate that dd-cfDNA is an early indicator of biopsy-proven rejection, especially ABMR, suggesting a greater role for dd-cfDNA in surveillance to identify patients at high risk of ongoing or future rejection, thus requiring closer monitoring, biopsy, or other management changes.
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Biomarcadores , Ácidos Nucleicos Livres , Rejeição de Enxerto , Transplante de Rim , Doadores de Tecidos , Humanos , Transplante de Rim/efeitos adversos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/sangue , Rejeição de Enxerto/diagnóstico , Ácidos Nucleicos Livres/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Biópsia , Biomarcadores/sangue , Adulto , Rim/patologia , Rim/imunologia , Sistema de Registros , Creatinina/sangue , Idoso , Fatores de Tempo , Valor Preditivo dos Testes , Estudos ProspectivosRESUMO
BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for SARS-CoV-2. It plays critical roles in both the transmission and the pathogenesis of COVID-19. Comprehensive profiling of ACE2 expression patterns could reveal risk factors of severe COVID-19 illness. While the expression of ACE2 in healthy human tissues has been well characterized, it is not known which diseases and drugs might be associated with ACE2 expression. RESULTS: We develop GENEVA (GENe Expression Variance Analysis), a semi-automated framework for exploring massive amounts of RNA-seq datasets. We apply GENEVA to 286,650 publicly available RNA-seq samples to identify any previously studied experimental conditions that could be directly or indirectly associated with ACE2 expression. We identify multiple drugs, genetic perturbations, and diseases that are associated with the expression of ACE2, including cardiomyopathy, HNF1A overexpression, and drug treatments with RAD140 and itraconazole. Our joint analysis of seven datasets confirms ACE2 upregulation in all cardiomyopathy categories. Using electronic health records data from 3936 COVID-19 patients, we demonstrate that patients with pre-existing cardiomyopathy have an increased mortality risk than age-matched patients with other cardiovascular conditions. GENEVA is applicable to any genes of interest and is freely accessible at http://genevatool.org . CONCLUSIONS: This study identifies multiple diseases and drugs that are associated with the expression of ACE2. The effect of these conditions should be carefully studied in COVID-19 patients. In particular, our analysis identifies cardiomyopathy patients as a high-risk group, with increased ACE2 expression in the heart and increased mortality after SARS-COV-2 infection.
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Enzima de Conversão de Angiotensina 2/isolamento & purificação , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/mortalidade , Cardiomiopatias/metabolismo , Doenças Cardiovasculares , Adulto , Idoso , Enzima de Conversão de Angiotensina 2/genética , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , RNA-Seq , Fatores de Risco , SARS-CoV-2RESUMO
Background: The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection causes coronavirus disease-2019 (COVID-19) in some individuals, while the majority remain asymptomatic. Natural killer (NK) cells play an essential role in antiviral defense. NK cell maturation and function are regulated mainly by highly polymorphic killer cell immunoglobulin-like receptors (KIR) and cognate HLA class I ligands. Herein, we tested our hypothesis that the individualized KIR and HLA class I ligand combinations that control NK cell function determine the outcome of SARS-CoV-2 infection. Methods: We characterized KIR and HLA genes in 200 patients hospitalized for COVID-19 and 195 healthy general population controls. Results: The KIR3DL1+HLA-Bw4+ [Odds ratio (OR) = 0.65, p = 0.03] and KIR3DL2+HLA-A3/11+ (OR = 0.6, p = 0.02) combinations were encountered at significantly lower frequency in COVID-19 patients than in the controls. Notably, 40% of the patients lacked both of these KIR+HLA+ combinations compared to 24.6% of the controls (OR = 2.04, p = 0.001). Additionally, activating receptors KIR2DS1+KIR2DS5+ are more frequent in patients with severe COVID-19 than patients with mild disease (OR = 1.8, p = 0.05). Individuals carrying KIR2DS1+KIR2DS5+ genes but missing either KIR3DL1+HLA-Bw4+ combination (OR = 1.73, p = 0.04) or KIR3DL2+HLA-A3/11+ combination (OR = 1.75, p = 0.02) or both KIR3DL1+HLA-Bw4+ and KIR2DL2+HLA-A3/11+ combinations (OR = 1.63, p = 0.03) were more frequent in the COVID-19 cohort compared to controls. Conclusions: The absence of KIR3DL1+HLA-Bw4+ and KIR3DL2+HLA-A3/11+ combinations presumably yields inadequate NK cell maturation and reduces anti-SARS-CoV-2 defense, causing COVID-19. An increased frequency of KIR2DS1+KIR2DS5+ in severe COVID-19 patients suggests vigorous NK cell response triggered via these activating receptors and subsequent production of exuberant inflammatory cytokines responsible for severe COVID-19. Our results demonstrate that specific KIR-HLA combinations that control NK cell maturation and function are underlying immunogenetic variables that determine the dual role of NK cells in mediating beneficial antiviral and detrimental pathologic action. These findings offer a framework for developing potential host genetic biomarkers to distinguish individuals prone to COVID-19.
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BACKGROUND: Endomyocardial biopsy (EMB), the reference surveillance test for acute rejection (AR) in heart transplant (HTx) recipients, is invasive, costly, and shows significant interobserver variability. Recent studies indicate that donor-derived cell-free DNA (dd-cfDNA), obtained non-invasively from blood, is associated with AR and could reduce the frequency of EMB surveillance. The aim of this study was to examine the performance characteristics of a novel test for detecting AR in adult HTx recipients. METHODS: Plasma samples with contemporaneous EMBs were obtained from HTx recipients. A clinically available SNP-based massively multiplexed-PCR dd-cfDNA assay was used to measure dd-cfDNA fraction. dd-cfDNA fractions were compared with EMB-defined rejection status and test performance was assessed by constructing ROC curves and calculating accuracy measures. RESULTS: A total of 811 samples from 223 patients with dd-cfDNA testing and contemporaneous EMB were eligible for the study. dd-cfDNA fraction was significantly higher in AR (median 0.58%, IQR, 0.13%-1.68%) compared to non-AR (median 0.04%, IQR, 0.01%-0.11%, pc < 0.001). ROC analysis produced an area under the curve (AUC-ROC) of 0.86 (95% CI, 0.77-0.96). Defining samples with dd-cfDNA fraction ≥0.15% as AR yielded 78.5% sensitivity (95% CI, 60.7%-96.3%) and 76.9% specificity (95% CI, 71.1%-82.7%). Positive and negative predictive values were 25.1% (95% CI, 18.8%-31.5%) and 97.3% (95% CI, 95.1%-99.5%) respectively, calculated using the cohort AR prevalence of 9.0% (95% CI, 5.3%-12.8%) with adjustment for repeat samples. CONCLUSIONS: This novel dd-cfDNA test detects AR in HTx recipients with good accuracy and holds promise as a noninvasive test for AR in HTx recipients.
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Ácidos Nucleicos Livres , Transplante de Coração , Adulto , Biomarcadores , Rejeição de Enxerto/genética , Humanos , Doadores de TecidosRESUMO
BACKGROUND: Donor-derived cell-free DNA (dd-cfDNA) fraction and quantity have both been shown to be associated with allograft rejection. The present study compared the relative predictive power of each of these variables to the combination of the two, and developed an algorithm incorporating both variables to detect active rejection in renal allograft biopsies. METHODS: The first 426 sequential indication biopsy samples collected from the Trifecta study ( ClinicalTrials.gov # NCT04239703) with microarray-derived gene expression and dd-cfDNA results were included. After exclusions to simulate intended clinical use, 367 samples were analyzed. Biopsies were assessed using the molecular microscope diagnostic system and histology (Banff 2019). Logistic regression analysis examined whether combining dd-cfDNA fraction and quantity adds predictive value to either alone. The first 149 sequential samples were used to develop a two-threshold algorithm and the next 218 to validate the algorithm. RESULTS: In regression, the combination of dd-cfDNA fraction and quantity was found to be significantly more predictive than either variable alone ( P = 0.009 and P < 0.0001). In the test set, the area under the receiver operating characteristic curve of the two-variable system was 0.88, and performance of the two-threshold algorithm showed a sensitivity of 83.1% and specificity of 81.0% for molecular diagnoses and a sensitivity of 73.5% and specificity of 80.8% for histology diagnoses. CONCLUSIONS: This prospective, biopsy-matched, multisite dd-cfDNA study in kidney transplant patients found that the combination of dd-cfDNA fraction and quantity was more powerful than either dd-cfDNA fraction or quantity alone and validated a novel two-threshold algorithm incorporating both variables.
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Ácidos Nucleicos Livres , Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Ácidos Nucleicos Livres/genética , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/genética , Estudos Prospectivos , Biomarcadores/análise , Doadores de Tecidos , Complicações Pós-OperatóriasRESUMO
BACKGROUND: Pancreas graft status in simultaneous pancreas-kidney transplant (SPKTx) is currently assessed by nonspecific biochemical markers, typically amylase or lipase. Identifying a noninvasive biomarker with good sensitivity in detecting early pancreas graft rejection could improve SPKTx management. METHODS: Here, we developed a pilot study to explore donor-derived cell-free DNA (dd-cfDNA) performance in predicting biopsy-proven acute rejection (P-BPAR) of the pancreas graft in a cohort of 36 SPKTx recipients with biopsy-matched plasma samples. dd-cfDNA was measured using the Prospera test (Natera, Inc.) and reported both as a fraction of the total cfDNA (fraction; %) and as concentration in the recipient's plasma (quantity; copies/mL). RESULTS: In the absence of P-BPAR, dd-cfDNA was significantly higher in samples collected within the first 45 d after SPKTx compared with those measured afterward (median, 1.00% versus 0.30%; median, 128.2 versus 35.3 cp/mL, respectively with both; P = 0.001). In samples obtained beyond day 45, P-BPAR samples presented a significantly higher dd-cfDNA fraction (0.83 versus 0.30%; P = 0.006) and quantity (81.3 versus 35.3 cp/mL; P = 0.001) than stable samples. Incorporating dd-cfDNA quantity along with dd-cfDNA fraction outperformed dd-cfDNA fraction alone to detect active rejection. Notably, when using a quantity cutoff of 70 cp/mL, dd-cfDNA detected P-BPAR with a sensitivity of 85.7% and a specificity of 93.7%, which was more accurate than current biomarkers (area under curve of 0.89 for dd-cfDNA (cp/ml) compared with 0.74 of lipase and 0.46 for amylase). CONCLUSIONS: dd-cfDNA measurement through a simple noninvasive blood test could be incorporated into clinical practice to help inform graft management in SPKTx patients.
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Ácidos Nucleicos Livres , Rejeição de Enxerto , Transplante de Rim , Transplante de Pâncreas , Biomarcadores , Ácidos Nucleicos Livres/genética , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/genética , Humanos , Transplante de Rim/efeitos adversos , Transplante de Pâncreas/efeitos adversos , Projetos Piloto , Complicações Pós-Operatórias , Doadores de TecidosRESUMO
A huge array of data in nephrology is collected through patient registries, large epidemiological studies, electronic health records, administrative claims, clinical trial repositories, mobile health devices and molecular databases. Application of these big data, particularly using machine-learning algorithms, provides a unique opportunity to obtain novel insights into kidney diseases, facilitate personalized medicine and improve patient care. Efforts to make large volumes of data freely accessible to the scientific community, increased awareness of the importance of data sharing and the availability of advanced computing algorithms will facilitate the use of big data in nephrology. However, challenges exist in accessing, harmonizing and integrating datasets in different formats from disparate sources, improving data quality and ensuring that data are secure and the rights and privacy of patients and research participants are protected. In addition, the optimism for data-driven breakthroughs in medicine is tempered by scepticism about the accuracy of calibration and prediction from in silico techniques. Machine-learning algorithms designed to study kidney health and diseases must be able to handle the nuances of this specialty, must adapt as medical practice continually evolves, and must have global and prospective applicability for external and future datasets.
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Big Data , Nefropatias , Nefrologia , Pesquisa Biomédica , Humanos , Nefropatias/diagnóstico , Nefropatias/terapiaRESUMO
AIM: Antineutrophil cytoplasmic antibody-associated vasculitis (AAV) is an autoimmune disease characterized by necrotizing small vessel vasculitis that can affect various organs and present multiple symptoms. Susceptibility to AAV is multifactorial and most likely caused by an amalgamation of genetic and environmental factors. The aim of the present study was to explore the distribution of human leukocyte antigen (HLA)-DRB1/DQB1, protein tyrosine phosphatase non-receptor type 22 (PTPN22) and cytotoxic T-Lymphocyte-associated protein 4 (CTLA-4) polymorphisms in North Indian AAV patients and their associations with clinical and pathological characteristics associated with the disease. METHODS: A total of 150 AAV patients and 150 healthy controls were recruited. The clinical classification showed 128 as granulomatosis with polyangiitis (GPA) and 21 as microscopic polyangiitis. Only 1 case of eosinophilic granulomatosis with polyangiitis was encountered, which was excluded from analysis. HLA-DRB1/DQB1 alleles were determined by polymerase chain reaction-sequence-specific primer (PCR-SSP) method and single nucleotide variant genotyping for CTLA-4 and PTPN22 was done by simple probe-based SNP arrays. RESULTS: A significant predispositional association of DRB1*03 and DQB1*02 alleles, were confirmed in proteinase 3 (PR3)-AAV patients, whereas DRB1*10, DRB1*14 and DQB1*05 were protective alleles in AAV, PR3-AAV and GPA patients. GG genotype of CTLA-4 + 49A/G was increased in patients as compared to controls and showed an association with AAV, PR3-AAV and GPA patients. CONCLUSION: The study indicated strong genetic associations were linked with PR3 antineutrophil cytoplasmic antibody specificity and it appears that PR3-AAV and MPO-AAV have distinct genetic backgrounds.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/genética , Antígeno CTLA-4/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Adulto , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Anticorpos Anticitoplasma de Neutrófilos/sangue , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Mieloblastina/imunologia , Peroxidase/imunologia , FenótipoRESUMO
Virtual crossmatch (VXM) compares a transplant candidate's unacceptable antigens to the HLA typing of the donor before an organ offer is accepted and, in selected cases, supplant a prospective physical crossmatch. However, deceased donor typing can be ambiguous, leading to uncertainty in compatibility prediction. We have developed a prototype web application that utilizes ambiguous HLA molecular typing data to predict which unacceptable antigens are present in the donor HLA genotype as donor-specific antibodies (DSA). The application compares a candidate's listed unacceptable antigens to computed probabilities of all possible two-field donor HLA alleles and UNOS antigens. The VIrtual CrossmaTch for mOleculaR HLA typing (VICTOR) tool can be accessed at http://www.transplanttoolbox.org/victor. We reanalyzed historical VXM cases where a transplant center's manual interpretation of molecular typing results influenced offer evaluation. We found that interpretation of ambiguous donor molecular typing data using imputation could one day influence VXM decisions if the DSA predictions were rigorously validated. Standardized interpretation of molecular typing data, if applied to the match run, could also change which offers are made. HLA typing ambiguity has been an underappreciated source of immunological risk in organ transplantation. The VICTOR tool can serve as a testbed for development of allocation policies with the aim of decreasing offers refused due to HLA incompatibility.
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Antígenos HLA/imunologia , Teste de Histocompatibilidade/métodos , Internet , Transplante de Órgãos , Software , Humanos , Seleção de PacientesRESUMO
Staphylococcus aureus isolated from the cervix of an infertile woman was found to cause complete immobilization of human spermatozoa in vitro. Only the cell culture and cell-free supernatant showed immobilization activity, indicating that the sperm immobilization factor might be released extracellularly by the organism because no activity was observed with the washed cells. Heat treatment of the supernatant at 60 degrees C for 10 min waived its immobilizing activity, indicating that the active component may be a protein. The bioactive molecule from the supernatant was purified to homogeneity by ammonium sulfate precipitation, gel permeation chromatography, and ion exchange chromatography. Sperm immobilization factor (SIF) was found to be an approximately 20 kDa protein. SIF at a concentration of 10 microg/mL was required to cause 100% immobilization of human spermatozoa after 30 min of incubation at 37 degrees C, whereas a concentration of 150 microg/mL caused immediate immobilization, and a concentration of 200 microg/mL resulted in instant loss of viability of human spermatozoa, observed by eosin-nigrosin staining. Scanning electron microscopy showed that the treatment of human spermatozoa with SIF caused multiple defects in the head, midpiece, neck, and tail region of human spermatozoa.
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Proteínas de Bactérias/isolamento & purificação , Imobilizantes dos Espermatozoides/isolamento & purificação , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Staphylococcus aureus/química , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , Humanos , Masculino , Peso Molecular , Imobilizantes dos Espermatozoides/química , Imobilizantes dos Espermatozoides/farmacologia , Espermatozoides/fisiologiaRESUMO
BACKGROUND: Histocompatibility labs must convert molecular HLA typing data to antigen equivalencies for entry into the United Network for Organ Sharing (UNOS) UNet system. While an Organ Procurement and Transplantation Network (OPTN) policy document provides general guidelines for conversion, the process is complex because no antigen mapping table is available. We present a UNOS antigen equivalency table for all IPD-IMGT/HLA alleles at the A, B, C, DRB1, DRB3/4/5, DQA1, and DQB1 loci. METHODS: An automated script was developed to generate a UNOS antigen equivalency table. Data sources used in the conversion algorithm included the World Marrow Donor Association (WMDA) antigen table, the HLA Dictionary, and UNOS-provided tables. To validate antigen mappings, we converted National Marrow Donor Program (NMDP) high resolution allele frequencies to antigen equivalents and compared with the UNOS Calculated Panel Reactive Antibodies (CPRA) reference panel. RESULTS: Normalized frequency similarity scores between independent NMDP and UNOS panels for 4 US population categories (Caucasian, Hispanic, African American and Asian/Pacific Islander) ranged from 0.85 to 0.97, indicating correct antigen mapping. An open source web application (ALLele to ANtigen ("ALLAN")) and web services were also developed to map unambiguous and ambiguous HLA typing data to UNOS antigen equivalents based on NMDP population-specific allele frequencies (http://www.transplanttoolbox.org). CONCLUSIONS: Computer-assisted interpretation of molecular HLA data may aid in reducing typing discrepancies in UNet. This work also sets a foundation for molecular typing data to be utilized directly in the UNet match run as well as the virtual crossmatch process at transplant centers.
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Mapeamento Cromossômico , Antígenos HLA/genética , Teste de Histocompatibilidade , Alelos , Biologia Computacional/métodos , Frequência do Gene , Antígenos HLA/imunologia , Teste de Histocompatibilidade/métodos , Humanos , Software , Estados Unidos , NavegadorRESUMO
There is wide variation in the prevalence of pancreatic and other major autoantibodies in different patient populations of Type 1 diabetes (T1D) across continents and even within countries. The data on frequency of associated autoimmunity Indian children with T1D is limited. A retrospective record review of 310 children aged 7.28±3.3 y (range 0.7-15 y) with recently diagnosed T1D attending our Pediatric Diabetes Clinic between April 2004 to September 2014, showed positivity for anti-GAD65, anti-IA2b, anti-TPO and anti-tTGA of 50% (64/128), 16% (12/72), 18.7% (23/123) and 22% (47/212) respectively. The male:female ratio in patients with anti-GAD, anti-TPO and anti-tTG positivity was 1.3, 0.7 and 0.6 respectively. In conclusion, our patient cohort exhibited a moderate prevalence of anti-GAD 65, low prevalence of anti-TPO and high prevalence of anti-tTGA autoantibodies as compared to previous reports. Male preponderance was noted in children with GAD65 positivity.
RESUMO
BACKGROUND: Autoimmune hepatitis is a polygenic disorder of unknown etiology, where genetic factors affect the occurrence and clinical phenotype of the disease. It has been reported as a rare disease entity in the Indian subcontinent. This study was undertaken to investigate the association of HLA alleles with autoimmune hepatitis type 1 and type 2 in north Indian population and to analyze if distinct human leukocyte antigen (HLA) alleles help in characterization of the subtypes of autoimmune hepatitis. METHODS: Sixty-eight patients with autoimmune hepatitis and 128 healthy controls were recruited in the study. Out of 68 patients, 55 were diagnosed with autoimmune hepatitis type 1 and 13 with autoimmune hepatitis type 2. The patients and the controls were typed for HLA class II alleles by PCR-SSP method. RESULTS: HLA DRB1*04 and DRB1*08 were found to be significantly associated with autoimmune hepatitis type 1 in north Indian population. It was also observed that DRB1*04, DRB1*13 were significantly associated with pediatric autoimmune hepatitis type 1 and DRB1*08 was significantly associated with adult autoimmune hepatitis type 1. DRB1*14 was significantly associated with autoimmune hepatitis type 2. CONCLUSION: The study indicates that autoimmune hepatitis in north Indian population is associated with HLA alleles that may help to discriminate the subtypes as autoimmune hepatitis type 1 and type 2. The study also highlights the ethnic variations in the Indian subcontinent in context to the genetic association of HLA with autoimmune diseases.
RESUMO
PURPOSE: This study describes the clinical, histological, and genetic profile of AMA-M2 positive liver disease in north India. METHODS: Over 13.5 years, 11,221 patients suspected of AiLD (autoimmune liver disease) and negative for viral markers were screened for autoantibodies, ANA, ASMA, AMA, and LKM, by indirect immunofluorescence. Of these patients, 135 were AMA positive and 132 AMA-M2 positive. Clinical presentation of most of these patients was neither typical of AIH nor PBC. Sera of these patients were further tested for gp 210 and Sp 100. Fifty consecutive consenting patients were typed for HLA class II alleles DR and DQ and their clinical, biochemical, histology and genetic profiles were reviewed to characterize the disease spectrum in north India. RESULTS: Only 22 of 50 patients had liver histology reports, and could be categorized on the basis of the criteria by Chazouillers et al. Of these 22, 13 had overlap syndrome, eight had classical PBC, whereas one had probable PBC. The remaining 28 could not be suitably categorized due to lack of liver histology. HLA DRB1*03 was found to be significantly associated with the disease in North Indian population. CONCLUSION: This 13.5-year study demonstrates a definite rising annual incidence of AMA-M2-positive liver disease in north India. Complete evaluation of 50 patients indicated that a hepatitic variant of PBC (PBC-AIH), which is significantly associated with DRB1*03, predominates in north India.