Type 1 Diabetes Early Diagnosis And Early Prevention And Treatment Research

To explore the role of the autoantibodies(GADA,IAA,ICA), the polymorphisms of chemokine receptor CCR5 , CCR2 , and the expression of CD4+CCR5+ and CD4+CCR3+ in the PBMC of the type 1 diabetes mellitus in prediction and diagnosis type 1 diabetes.Meterials and methods1. The autoantibodies levels (GAD A, 1C A, IAA) in the nondiabetic group (n=25), T1DM group (n=48), the first relative group (n=57), the T2DM group (n=104) were measured with the ELISA method.2. CCR5A32 were detected by polymerase chain reaction(PCR) in T1DM (n=48), the first relations(n=57),T2DM (n=104), non-diabetic control (n=94) and CCR2-64I were also detected in these groups by polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP).3. The expressions of CD4+CCR5+ or CD4+CCR3* in the PBMC of T1DM (n=15), T2DM (n=10), non-diabetic control (n=10) were analyzed with the flow cytometroy. The IL-4 and IFN-r level in the cell supernatant were assayed with the ELISA kits.Results(1) In the nondiabetic control group, 4% had GAD A, none had 1C A and IAA. Among the type 1 diabetic groups, 65% had GAD A, 31% had ICA, and 38% had lAA.In the first relative of type 1 diabetic patients, 21% had GADA, 9% had ICA, and 11% had IAA.Among the type 2 diabetic groups, 4.8% had GADA, 1% had ICA, and none had lAA.The are significiantly difference between type 1 diabetic group and nondiabeticgroup in three antibodies (p<0.01).(2) There were no significantly difference in CCR5 A 32 genotype frequencies or allele frequencies between type 1 diabetics ,the first relatives of type 1 diabetics, type 2 diabetics and non-diabetic controls respectively. But CCR2-64I genotype frequencies or allele frequencies in type 1 diabetics was significantly higher than non-diabetic controls whereas CCR2-64I in type 2 diabetics is lower than type 1 diabetics.(3) The number of CD4+CCR5+ lymphocyte of T1DM was significantly higher than T2DM and control group (P<0.05) while the expression of CD4+CCR3+ was lower than other two groups. There was no difference between type 2 diabetes and control group (P>0.05)The Level of IFN- γ was higher in T1DM and T2DM than control group(P<0.05). The level of IL-4 in T1DM was lower than the other two groups ((P<0.05) while there was no difference between T2DM and control groups (P>0.05).Conclusion1. GADA, ICA, IAA may predict and diagnosis type 1 diabetes.2. CCR5A32 has no relationship to type 1 diabetes. CCR2-64I is significantly associated with type 1 diabetes and maybe it is a new candidate gene for the susceptibility locus of type 1 diabetes.3. In type 1 diabetes,the expression of CCR5,a characteristic of Thl lymphocytes,was increased while the expression of CCR3,a characteristic of Th2 lymphocytes decreased that might indicate the augment of the capacity of the lymphocyte migration and differentiating to Thl type cell.Our data also indicated that the production of Thl type cytokines such as IFN- Y was increased while Th2 type cytokine IL-4 was decreased.These results are coincidence with the conclusion of the chemokine receptor studies. This study give a direct and strong evdience to support that Thl lymphocyte contribute to the deveolpmentof autoimmune diabetes. It maybe gives us a new method to screen and treat the type 1 diabetes in early period.