HLA class I genes modulate disease risk and age at onset together with DR-DQ in Chinese patients with insulin-requiring type 1 diabetes.

AIMS/HYPOTHESIS: The study aimed to investigate the effects of HLA class I genes on susceptibility to type 1 diabetes with different onset ages, in addition to the well-established effects of HLA class II genes. METHODS: A total of 361 patients with type 1 diabetes (192 patients with onset <18 years and 169 patients with onset ≥18 years) and 500 healthy control participants from China were enrolled and genotyped for the HLA-A, -B, -C, -DQA1, -DQB1 and -DRB1 genes using next-generation sequencing. RESULTS: The susceptible DR3 (ß = -0.09, p = 0.0009) and DR4-DQ8 (ß = -0.13, p = 0.0059) haplotypes were negatively associated with onset age, while the protective DR11 (ß = 0.21, p = 0.0314) and DR12 (ß = 0.27, p < 0.0001) haplotypes were positively associated with onset age. After adjustment for linkage disequilibrium with DR-DQ haplotypes, A*11:01:01 was positively associated with onset age (ß = 0.06, p = 0.0370), while the susceptible C*15:02:01 was negatively associated with onset age (ß = -0.21, p = 0.0050). The unit for ß was double square-root (fourth root) transformed years of change in onset age associated with per copy of the HLA haplotype/allele. In addition, B*46:01:01 was protective (OR 0.41, 0.46; pc [corrected for multiple comparisons] = 0.0044, 0.0040), whereas A*24:02:01 (OR 2.71, 2.25; pc = 0.0003, 0.0002) and B*54:01:01 (OR 3.96, 3.79; pc = 0.0018, 0.0004) were predisposing in both the <18 group and the ≥18 group compared with healthy control participants. In the context of DR4-DQ4, A*11:01:01 (61.29% vs 28.26%, pc = 0.0144) was increased while the predisposing A*24:02:01 (19.35% vs 47.83%, pc = 0.0403) was decreased in patients with onset ≥18 years when compared with patients with onset <18 years. CONCLUSIONS/INTERPRETATION: In addition to DR-DQ haplotypes, novel HLA class I alleles were detected to play a role in susceptibility to type 1 diabetes with different onset ages, which could improve the understanding of disease heterogeneity and has implications for the design of future studies.

Adult-onset type 1 diabetic patients with less severe clinical manifestation have less risk DR-DQ genotypes than childhood-onset patients.

BACKGROUND: The aim of this study was to investigate differences in clinical features and HLA genotypes between adult-onset and childhood-onset patients with type 1 diabetes in a Chinese population. MATERIALS AND METHODS: This study enrolled 716 Han Chinese patients with type 1 diabetes from Guangdong (258 childhood-onset and 458 adult-onset) to compare their clinical features. Of them 214 patients with classical type 1 diabetes (100 childhood-onset and 114 adult-onset) were selected for HLA DR and DQ genotyping by next-generation sequencing. RESULTS: Adult-onset patients were characterized by longer duration of symptoms before diagnosis, lower frequency of DKA at disease onset, less frequent autoantibody positivity, higher serum C-peptide concentrations, and better glycemic control. These findings were replicated in the restricted cohort of 214 patients with classical type 1 diabetes. Compared with childhood-onset patients, adult-onset patients had a lower frequency of the DR9 haplotype, as well as lower frequency of high-risk DR3/DR4 and DR3/DR9 genotypes, but higher frequency of DR3/DR3 genotype and DR3/X, DR4/X or DR9/X (X, non-risk) genotypes. CONCLUSIONS: Adult-onset type 1 diabetic patients with susceptible haplotypes (DR3, DR4 or DR9) were more likely to carry protective DR-DQ haplotypes than childhood-onset patients, which suggested the association between less risk DR-DQ genotypes and the less severe clinical manifestation in adult-onset patients.

A pilot study of preproinsulin peptides reactivity in Chinese patients with type 1 diabetes.

BACKGROUND: The aim of our study is to investigate whether preproinsulin (PPI) could trigger a proinflammatory CD4+ T cell response in Chinese patients with type 1 diabetes (T1D). METHODS: Peripheral blood mononuclear cells were stimulated by a pool of 13 PPI peptides. Additional five PPI peptides previously proved to be antigenic in other cohorts of patients with T1D were also used. PPI reactive T cell responses were measured by interferon (IFN)-γ ELISPOT assay. RESULTS: Fifty-one Chinese patients with T1D were enrolled in this study and 72.34% of them were positive for at least one islet autoantibody. The stimulation index (SI) value of IFN-γ response to PPI peptide pool or peptides with dominant epitopes was below 3 in patients when SI≥3 was used as the positive cut-off value. Two peptides (B9-23 and C19-A3) restricted to DQ8 or DR4 molecule failed to induce positive IFN-γ response in patients with high-risk HLA-DQ8 or HLA-DR4/DR9 alleles. RNA-seq analysis of PPI specific CD4+ T cell lines further showed that most of the IFN-γ associated genes remained unchanged. CONCLUSIONS: This is the first report of CD4+ T cell epitope mapping of PPI in Chinese T1D. The lack of positive IFN-γ response to PPI peptides indicates that PPI might not be the principal antigenic candidate for autoreactive CD4+ T cells in Chinese T1D. Therefore, the efficacy of PPI-based immunotherapies in attenuating proinflammatory CD4+ T cell response requires further investigation.

Effect of weight loss on proteinuria in adults with type 2 diabetes: A real-world study.

AIMS: To assess the impact of weight loss on proteinuria in patients with type 2 diabetes (T2DM) in real-world settings. METHODS: A total of 1054 participants were categorized based on weight change from baseline to one-year follow-up: weight gain (≥3%), stable weight, or weight loss (≥3%). Proteinuria outcomes were defined as urinary albumin/creatinine ratio (UACR) progression (≥30 % increase), UACR regression (≥30 % reduction), or UACR stable. Ordered logistic regression analysis evaluated the relationship between weight loss and UACR regression. RESULTS: Of the 1054 participants, 44.5 % were overweight, and 24.1 % were obese. Patients with obesity were at higher risk of developing proteinuria (OR, 1.783; 95 %CI, 1.195 to 2.659). Weight loss was associated with an 83.3 % increase in UACR regression compared to weight gain (OR, 1.833; 95 % CI, 1.262 to 2.663; P = 0.001). This association remained consistent across most subgroups and stronger in males (P for interaction = 0.023), with a 6 % UACR regression for every 1 kg weight loss (OR, 1.06; 95 % CI, 1.02 to 1.10; P = 0.003). CONCLUSIONS: Our real-world study reveals that weight reduction is associated with UACR regression in patients with T2DM, regardless of the approach used for weight management, and the association was much stronger in males.