RESUMO
BACKGROUND: This study was undertaken in order to analyze the genetic incidence of human lymphocyte antigen diabetic retinopathy (HLA-DR) and its influence in proliferative diabetic retinopathy (PDR). METHODS: We designed a case-control study in which 127 mestizo Mexican patients with DM II and diabetic retinopathy were studied. DNA was extracted and HLA-DR regions were amplified using PCR. Alleles were determined by DNA hybridization. Diagnosis was assessed clinically and by fluorescein angiography. Incidence of HLA-DR alleles in patients was compared with an ethnically matched control group of healthy subjects (n = 98). Statistical significance was established with non-parametric tests. RESULTS: Patients with diabetic retinopathy showed less frequency of HLA-D11 compared with the control group (p = 0.043). NPDR patients with 10 or more years of DM II showed an increase of HLA-DR7 (p = 0.01). CONCLUSIONS: Our results suggest that the presence of HLA-DR7 protects against the development of proliferative disease in the diabetic Mexican population.
Assuntos
Diabetes Mellitus Tipo 2/genética , Retinopatia Diabética/genética , Antígeno HLA-DR7/fisiologia , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/imunologia , Retinopatia Diabética/imunologia , Progressão da Doença , Feminino , Frequência do Gene , Antígeno HLA-DR7/genética , Antígeno HLA-DR7/imunologia , Humanos , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , México , Pessoa de Meia-IdadeRESUMO
We studied IgG and IgM anticardiolipin antibodies (aCL) by an ELISA method in 80 Mexican systemic lupus erythematosus (SLE) patients and 378 of their first degree relatives. Sixty five percent of SLE patients and 16% of their relatives were positive for aCL. We also determined allele and haplotype frequencies of Major Histocompatibility Complex (MHC) genes (classes I, II and III) in both patients and relatives. MHC allele and haplotype frequencies of aCL positive and negative individuals were compared to those of normal ethnically matched controls. SLE patients with aCL had statistically significant increased corrected frequencies of HLA-DR3 (pC = 0.04, RR = 2.78); DR7 (pC = 0.005), RR = 3.42) and DQ2 (pC = 0.003, RR = 2.58) antigens. Their first degree relatives positive for aCL also had increased frequency of HLA-DR7 but it did not remain significant after correcting the P value. On the other hand, SLE patients negative for aCL had a moderate increased frequency of DR3 and DQ2 but not of DR7. These results suggest that DR7 associates with the presence of aCL. The distribution of MHC alleles in SLE patients positive for aCL resembles that found in their aCL positive first degree relatives. Since the presence of the antibody is not sufficient to predict a clinical outcome, we studied those patients with reliable clinical data regarding the presence of the antiphospholipid syndrome (aPLS). SLE patients with aPLS had significantly increased frequency of DR7 (pC = 0.004), as did those with probable aPLS (pC = 0.05), while the frequency of DR7 in SLE patients in the doubtful or negative aPLS categories was no different from normal controls. These data support a possible role of DR7 in the development of aCL in SLE patients and their relatives and suggest a contribution of this class II MHC antigen to the development of aPLS within SLE.
Assuntos
Anticorpos Anticardiolipina/imunologia , Síndrome Antifosfolipídica/imunologia , Antígeno HLA-DR7/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Alelos , Síndrome Antifosfolipídica/epidemiologia , Síndrome Antifosfolipídica/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Frequência do Gene , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/imunologia , Antígeno HLA-DR3/genética , Antígeno HLA-DR3/imunologia , Antígeno HLA-DR7/genética , Haplótipos , Humanos , Imunoglobulina G/análise , Imunoglobulina M/análise , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/genética , Masculino , México/epidemiologia , LinhagemRESUMO
We performed a study of antigens HLA type I and II (specificity DR) in 90 patients with diagnosis of Rheumatoid Arthritis (RA) treated with Sodium Aurothiomalate (SATM) in order to detect the presence of an antigen HLA which could act as a protective factor against toxicity by SATM. Our results demonstrated a decrease in the frequency of the antigen DR7 in patients with toxicity by SATM, which suggests a protective factor of this antigen against the development of toxic reactions due to gold salts.