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ABSTRACT: Fulminant type 1 diabetes (FT1D) is an extremely aggressive disease characterized by the abrupt onset of insulin-deficient hyperglycemia. However, the precise mechanisms underlying disease etiology almost remain unclear. As mice deficient in regulatory T cells (Tregs) are prone to the development of an FT1D-like phenotype, we thus investigated whether FT1D patients manifest Treg deficiency and explored the related mechanisms. We first noted a significant reduction for Foxp3 and CTLA4 expression levels in PBMCs of FT1D patients. IRF-7 was found to selectively bind to the Foxp3 promoter, and by which it promotes Foxp3 transcription. Therefore, ectopic IRF-7 expression significantly promoted Foxp3 and CTLA4 expression in PBMCs, while knockdown of IRF-7 manifested opposite effect. Importantly, stimulation of PBMCs with CpG ODN, a ligand for TLR9, significantly induced Foxp3 expression, demonstrating that TLR9 signaling positively regulates Treg development. However, knockdown of IRF-7 expression almost completely diminished the enhancing effect of TLR9 signaling on Foxp3 expression, suggesting that IRF-7 is a downstream molecule of TLR9 signaling and is essential for TLR9 induced Treg generation. Of interestingly note, the Foxp3 promoter in FT1D patients was hypermethylated, indicating that DNA methylation could be a causative factor responsible for the reduced Foxp3 expression in FT1D patients. Indeed, our mechanistic studies revealed that DNA methylation blocked IRF-7 binding to the Foxp3 promoter. Together, our data support the notion that environmental insults in genetic predisposed subjects trigger Foxp3 promoter hypermethylation, which then prevents IRF-7 binding to the Foxp3 promoter and impairs Treg development/functionality contributing to the pathogenesis of FT1D.
Journal of Autoimmunity 03/2013; · 7.37 Impact Factor
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ABSTRACT: BACKGROUND: Diabetic patients with positive glutamic acid decarboxylase antibody (GAD-Ab) could be classified as autoimmune diabetes, which is discriminated into acute-onset classical type 1 diabetes (T1DM) and latent autoimmune diabetes in adults (LADA). However, whether the decay rate of beta cell function is relevant with the mode of onset (acute or latent-onset) is unclear. We aimed to investigate whether initial C peptide levels could help differentiate variation of C peptide decay rate. METHODS: Five hundred and twenty-seven newly diagnosed GAD-Ab positive diabetic patients were followed up to assess the natural course of beta cell function. Beta cell function failure was defined as fasting C peptide and postprandial C peptide levels less than 100 pmol/L and 150 pmol/L respectively. RESULTS: All these diabetic patients were discriminated according to initial fasting C peptide of 300 pmol/L, that is B+ (larger than 300 pmol/L) and B- (less than 300 pmol/L) group. The proportion of developing beta cell function failure was 13.1% in B+ group and 90.5% in B- group, which suggested that fasting C peptide levels made a good distinction of the heterogeneity in autoimmune diabetes. Receiver operator characteristic (ROC) analysis suggested that the fasting C peptide level of 300 pmol/L was optimal for determining beta cell function failure with sensitivity of 90.5% and specificity of 86.9%. CONCLUSIONS: Initial level of fasting C peptide is a good indicator for predicting beta cell function failure in GAD-Ab positive diabetic patients.
BMC Endocrine Disorders 03/2013; 13(1):10. · 2.16 Impact Factor
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ABSTRACT: Objective: To explore the better freezing protocol to preserve peripheral blood monuclear cells (PBMCs), islets antigen-specific T cells responses compared with freshly isolated samples in type 1 diabetic (T1D) patients. Methods: The T cell Workshop Committee of the Immunology of Diabetes Society (IDS-TCW) organized the Freezing Study I and we were one of the 9 centers in the world to participate in the study. According to the two standardized T cell freezing protocols (warm and cold) to freshly isolated PBMCs in terms of recovery, viability, cell subset composition (FACS) and performance in Enzyme-linked immunospot (ELISPOT) assays, we chose 5 newly onset T1D patients and 5 age and sex matched healthy controls. Besides the protocols, all the freezing reagents and antigens were also centralized. The antigens used in ELISPOT were labeled blindedly. Results: 1) Although warm frozen-thawed (W) samples had a slightly higher recovery rate (61.2% vs 60.1%, P>0.05) and viability (77.5% vs 74.9%, P>0.05) as compared with the cold frozen ones (C), the difference was not significant. 2) Both protocols led to a relative loss in monocytes as compared with the fresh samples (F) [3.2±1.1% (C) and 3.0±0.9% (W) vs 7.0±1.1% (F), both P<0.05], while other subsets including CD4+T, CD8+T, B cells, NK cells and NKT cells didn't. 3) Freezing and fresh samples showed similar IFN-γ secretion responses to polystimuli in ELISPOT. Irrespective of the freezing protocol, recall antigen Pediacel and islet antigen-reactive responses were both lower in the frozen cells compared with fresh PBMCs. The stimuli index (SI) of GADspecific T cell response in the fresh samples from T1D patients was 5.1, higher than that of frozen samples with either cold protocol (1.3) or warm one (1.4) (both P<0.05). Only fresh samples from T1D showed significantly higher GAD-specific T cell responses than the healthy controls no matter in SI (5.1 vs 0.9, P<0.05) or spot forming cells (8.1 vs 0.1, P<0.05), whereas the frozen samples did not show such difference. Conclusion: More studies are needed to verify a freezing method to bring comparable islets antigen specific T cell responses in T1D patients to fresh PBMCs.
Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences 02/2013; 38(2):169-75.
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Zhiguang Zhou,
Yufei Xiang,
Linong Ji,
Weiping Jia,
Guang Ning,
Gan Huang, Lin Yang,
Jian Lin,
Zhenqi Liu,
William A Hagopian,
R David Leslie
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ABSTRACT: Adult non-insulin requiring diabetes includes latent autoimmune diabetes of adults (LADA), distinguished from type 2 diabetes by the presence of islet autoantibodies. LADA China determined the characteristics of Chinese LADA. This nationwide, multicenter, clinic-based cross-sectional study was conducted in 46 university-affiliated hospitals in 25 Chinese cities. All 4,880 ketosis-free diabetic patients (<1 year postdiagnosis, without insulin therapy for >6 months, aged ≥30 years) had GAD antibody (GADA) and HLA-DQ genotype measured centrally with clinical data collected locally. GADA-positive subjects were classified as LADA. Of the patients, 5.9% were GADA positive with LADA. LADA showed a north-south gradient. Compared with GADA-negative type 2 diabetes, LADA patients were leaner, with lower fasting C-peptide and less metabolic syndrome. Patients with high GADA titers are phenotypically different from those with low GADA titers, while only a higher HDL distinguished the latter from those with type 2 diabetes. HLA diabetes-susceptible haplotypes were more frequent in LADA, even in those with low-titer GADA. HLA diabetes-protective haplotypes were less frequent in LADA. Our study implicates universal immunogenetic effects, with some ethnic differences, in adult-onset autoimmune diabetes. Autoantibody positivity and titer could be important for LADA risk stratification and accurate therapeutic choice in clinical practice.
Diabetes 10/2012; · 8.29 Impact Factor
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ABSTRACT: Fibroblast growth factor (FGF) 21 is an endocrine factor with multiple beneficial effects on glucose and lipid metabolism in animals. This study aimed to investigate the association of serum FGF21 levels with type 1 diabetes, latent autoimmune diabetes in adults (LADA) and type 2 diabetes.
Serum FGF21 levels were determined by ELISA in patients with type 1 diabetes (n = 76), LADA (n = 68), type 2 diabetes (n = 77), and their age- and sex-matched controls. The association of serum FGF21 with markers of autoimmunity was studied.
In type 1 diabetic patients, serum FGF21 levels were significantly lower than controls [108.3 (61.5-180.1) vs. 196.0 (103.7-330.9) pg/ml, P < 0.001]. In LADA patients, serum FGF21 levels were significantly lower than controls after adjustment for body mass index [210.9 (121.4-441.6) vs. 268.3 (159.5-443.6) pg/ml, P = 0.003]. By contrast, serum FGF21 levels in type 2 diabetic patients were significantly higher than controls [381.2 (244.7-531.3) vs. 301.4 (173.9-444.2) pg/ml, P = 0.006]. FGF21 levels increased progressively from type 1 diabetes, LADA, to type 2 diabetes (P < 0.001 for global trend). Furthermore, FGF21 levels correlated inversely with titers of glutamic acid decarboxylase and insulinoma-associated protein 2 autoantibodies in type 1 diabetic and LADA patients.
Serum FGF21 level is increased in type 2 diabetes but decreased in type 1 diabetes and LADA. In autoimmune diabetes, the reduction in circulating FGF21 is closely associated with markers of pancreatic β-cell autoimmunity.
The Journal of clinical endocrinology and metabolism 01/2012; 97(1):E54-8. · 6.50 Impact Factor
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ABSTRACT: To clarify the detailed distribution, clinical and immunological features of patients with fulminant type 1 diabetes (F1D), we consecutively investigated 53 cases from nationwide 24 hospitals in China. After the clinical and immunological features were evaluated, we compared pregnancy-associated F1D (PF) with those of child-bearing age with F1D that was not associated with pregnancy in clinical characteristics. As a result, patients with F1D were reported from all over China, and there was no significant regional and seasonal preference of this disease. Around 34.0% (18/53) patients displayed low titers of autoantibodies against one or more autoantigens, including 12 cases positive for GADA, 2 for IA-2A, 4 for ZnT8A and 3 for both GADA and ZnT8A. The frequency of PF in female F1D was 34.6% (9/26). Among 9 PF patients, 8 (88.9%) developed F1D during pregnancy which resulted in stillbirth, while one had the onset of F1D after eutocia with her fetus survived. This study suggests that islet-associated autoimmunity may be involved in and contribute to the development of F1D. Pregnant women may be PF high-risk population, and the prognosis for the fetus is extremely poor in PF patients.
Acta Diabetologica 12/2011; · 2.78 Impact Factor
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ABSTRACT: Fulminant type 1 diabetes (F1D) is a complex disease. Microarray analysis was used to identify gene expression changes and obtain understanding of the underlying mechanisms.
Microarray analysis was performed on peripheral blood mononuclear cells from six F1D patients and six matched healthy subjects. Real-time polymerase chain reaction was used to verify the differentially expressed genes. NK cell activity was detected by methyl thiazoleterazolium assay.
Microarray analysis identified 759 genes differing in expression between F1D patients and controls at a false discovery rate of 0.05. Expression of TLR9, ELF4 and IL1RAP were verified and consistent with changes in microarray results. NK cell activity was decreased in F1D. With use of a knowledge base, differentially expressed genes could be placed within different pathways with predicted functions including interleukin-1, and tumor necrosis factor-α signaling.
These results identify several genes indicating possible mechanisms in F1D. NK cell dysfunction resulting from changes in expression of TLR9, ELF4 and IL1RAP, and pathways of interleukin-1 and tumor necrosis factor-α signaling might be involved in F1D through inducing β-cell dysfunction.
Chinese medical journal 11/2011; 124(22):3613-7. · 0.86 Impact Factor
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ABSTRACT: Aberrant DNA methylation in T cells has been linked to pathogenesis of autoimmune diseases. To investigate genomic and gene-specific DNA methylation levels in CD4(+) T cells from patients with latent autoimmune diabetes in adults (LADA), and to investigate changes in the expression of genes that regulate methylation as well as the autoimmune-related gene FOXP3 in these patients. Global CD4(+) T cell DNA methylation was measured in 15 LADA patients and 11 healthy controls using a methylation quantification kit. mRNA levels of DNA methytransferases (DNMTs), methyl-DNA binding domain proteins (MBDs) and FOXP3 were measured by real time PCR. Methylation of a FOXP3 regulatory element region was determined by bisulphite genomic sequencing. Genomic DNA methylation in CD4(+) T cells from LADA patients was significantly increased compared to controls. DNMT3b mRNA levels were higher in CD4(+) T cells from LADA patients than in controls. DNMT3b expression positively correlated with global DNA methylation in LADA CD4(+) T cells. FOXP3 expression was decreased, and the FOXP3 promoter region was hypermethylated in CD4(+) T cells from LADA patients compared with controls. DNA methylation levels are altered in CD4(+) T cells from LADA patients, which may contribute to disease onset and progression by affecting the expression of autoimmune-related genes.
Diabetes research and clinical practice 08/2011; 94(2):242-8. · 2.16 Impact Factor
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ABSTRACT: Type 1 diabetes mellitus (T1DM) is frequently associated with autoimmune thyroid diseases (AITD), but little is known about the risk of AITD in latent autoimmune diabetes in adults (LADA). We evaluated the genetic and immunological factors involved in the development of thyroid autoimmunity in patients with LADA and T1DM.
One hundred and ninety T1DM and 135 LADA patients were recruited in the study. Thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb), glutamic acid decarboxylase antibody (GADA) and thyroid function were measured. The cytotoxic-lymphocyte-associated antigen-4 (CTLA-4) +49A/G and CT60 polymorphisms and the human leucocyte antigen (HLA)-DQA1-DQB1 genotype were determined.
The prevalence of thyroid antibodies (TGAb and/or TPOAb) and thyroid dysfunction was 27·4% and 9·5% in patients with T1DM, and 21·5% and 11·1% in patients with LADA. Thyroid-antibody-positive T1DM patients had higher frequencies of GADA and HLA-DQA1*03-DQB1*0401 haplotypes than thyroid-antibody negatives (P < 0·05). Thyroid-antibody-positive LADA patients had higher GADA titre, lower C-peptide levels and higher frequencies of HLA-DQA1*03-DQB1*0401 haplotypes (P < 0·05). The CTLA-4 +49A/G and CT60 polymorphism was associated with T1DM complicated with thyroid autoimmunity (OR = 2·33 and 2·54). Logistic regression revealed that only high-titre GADA was associated with development of thyroid autoimmunity in patients with T1DM and LADA (OR = 3·50 and 3·10, respectively), and the presence of thyroid antibody predicted high risk for thyroid dysfunction in patients with T1DM and LADA (OR = 9·25 and 10·70, respectively).
Regular screening of thyroid antibody and function are recommended, especially in patients with T1DM and LADA with high GADA titre.
Clinical Endocrinology 05/2011; 74(5):587-92. · 3.17 Impact Factor
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ABSTRACT: fulminant type 1 diabetes mellitus (T1DM) is characterized by abrupt onset of hyperglycemia and rapid progression to ketoacidosis. This study aimed at examining the clinical and autoimmunity features of fulminant T1DM in Chinese.
a total of 24 patients with fulminant T1DM and 48 classical autoimmune T1DM patients with acute onset of ketoacidosis were recruited. Anthropometric and biochemical parameters were tested. Serum antibodies against glutamic acid decarboxylase 65, tyrosine phosphatase-2 and zinc transporter 8 were measured, and human leukocyte antigen-DQ haplotypes were determined. Peripheral glutamic acid decarboxylase 65-specific T-cell responses in some subjects were determined.
compared with autoimmune T1DM patients, patients with fulminant T1DM displayed more flu-like and gastrointestinal symptoms, and had significantly higher concentrations of plasma glucose, more severe ketoacidosis, very low levels of pancreatic β-cell reserve, but only slightly increased haemoglobin A(1c) levels. In some patients, the disease onset was associated with drug-related hypersensitivity, pregnancy, or positive serum IgM against viruses. Forty percent (8/20) had low titres of autoantibodies against at least one of the islet autoantigens tested. Three out of six patients had positive glutamic acid decarboxylase-reactive Th1 responses. The frequency of human leukocyte antigen -DQA1*0102-DQB1*0601 haplotype was significantly higher in patients with fulminant T1DM.
fulminant T1DM is a distinct entity with unique clinical characteristics and may be mediated by multiple factors, including viral infection, pregnancy, and drug sensitivity syndrome, among others, in the presence of humoral and/or cellular autoimmunity and susceptible genetic background.
Diabetes/Metabolism Research and Reviews 01/2011; 27(1):70-8. · 3.37 Impact Factor
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Lin Yang,
Shuoming Luo,
Gan Huang,
Jian Peng,
Xia Li,
Xiang Yan,
Jian Lin,
Janet M Wenzlau,
Howard W Davidson,
John C Hutton,
Zhiguang Zhou
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ABSTRACT: Zinc transporter-8 (ZnT8) was recently identified as a novel autoantigen in human type 1 diabetes (T1D). Autoantibody to ZnT8 (ZnT8A) was detected in up to 80% of patients with new-onset T1D and 26% of patients with T1D otherwise classified as negative on the basis of existing markers. As no data of ZnT8A in Chinese have been reported, we aim to evaluate the utility of ZnT8A for diagnosis of autoimmune T1D in Chinese relative to other autoantibody markers.
Radioligand binding assays were performed on 539 T1D sera using human ZnT8 carboxyterminal 325Arg construct or a dimer incorporating 325Arg and 325Trp alongside antibodies to glutamic acid decarboxylase (GADA) or insulinoma-associated protein 2 (IA-2A). The antigenic specificity was analysed in the context of clinical characteristics of the patients.
ZnT8A were present in 24.1% (130 of 539) of patients with T1D versus 1.8% (10 of 555; P < 0.001) in type 2 diabetes. At diagnosis, ZnT8A and IA-2A were less prevalent in Chinese subjects with T1D than in Caucasian populations (both P < 0.001) but similar to Japanese. The diagnostic sensitivity of combined GADA, IA-2A and ZnT8A measurements reached 65.5% with ZnT8A detected in 13.5% (29 of 215) of GADA and/or IA-2A-negative subjects. ZnT8A prevalence was lower in older and fatter patients. ZnT8A+ alone patients were distinguished from Ab- ones (P < 0.05-0.001) on the basis of higher insulin requirement and lower systolic blood pressure level.
ZnT8A is an independent marker for T1D in Chinese and combined with GADA and IA-2A enhances diagnostic sensitivity. ZnT8A may be associated with different clinical phenotypes than GADA or IA-2A.
Diabetes/Metabolism Research and Reviews 10/2010; 26(7):579-84. · 3.37 Impact Factor
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ABSTRACT: to explore the application significance of zinc transporter 8 autoantibody (ZnT8A) in the diagnostic classification of acute-onset diabetics.
according to the status of glutamic acid decarboxylase antibody (GADA) and tyrosine phosphatase antibody (IA2-A), 453 acute-onset diabetics were divided into A+ subgroup (any antibody positive) and A- subgroup (both antibodies negative). A total of 555 type 2 diabetics and 405 healthy controls were recruited. The distribution and correlated factors of ZnT8A were analyzed in the acute-onset diabetic group and two subgroups (A+ and A-). The clinical characteristics were compared between the patients with ZnT8A positive alone and patients without any antibody. All these islet antibodies were measured by radioligand assay.
the prevalence of ZnT8A in acute-onset diabetics was 24.3% and it was significantly higher than that in type 2 diabetics (1.8%) and healthy controls (1.0%) (both P < 0.01). The frequency of ZnT8A in A+ subgroup was much higher than A- subgroup (29.7% vs 15.8%, P < 0.01). The positive rates of ZnT8A were much higher in all the subgroups with age at onset of < 30 yr than those with ≥ 30 yr (0 - 9, 34.9%; 10 - 19, 26.7%; 20 - 29, 26.3% vs ≥ 30 yr, 18.3%; all P < 0.05); furthermore, the rates were also higher in BMI < 21.0 kg/m(2) and 21.0 - 25.0 kg/m(2) subgroups than in BMI > 25.0 kg/m(2) subgroup (25.5% and 25.9% vs 8.7%, both P < 0.05). The ZnT8A level was only positively correlated with IA2-A titer (r = 0.165, P = 0.01), but not related to such factors as GADA titer, age at onset, duration, body mass index, HbA1c and CP levels (all P > 0.05). As compared with Ab- patients, the patients with ZnT8A positive alone had much higher insulin injection dosage [(35.5 ± 9.3) U/d vs (29.8 ± 14.7) U/d, P < 0.05], and much lower systolic blood pressures [(107 ± 15) mm Hg vs (113 ± 16) mm Hg, P < 0.05] and diastolic blood pressures [(69 ± 12) mm Hg vs (73 ± 12) mm Hg, P < 0.05].
ZnT8A testing may be applied in the diagnostic classification of acute-onset diabetics, especially in those without an evidence of GADA and IA2-A since it helps to identify a clinical phenotype which is more similar to the classic type 1 diabetes.
Zhonghua yi xue za zhi 09/2010; 90(36):2536-40.
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ABSTRACT: Baseline drift of pulse waveform caused by breathing and physical movement needs to be removed in pulse wave detection process. This paper presents a removal method of pulse waveform baseline drift using cubic spline interpolation. Methods: Starting points of pulse waveform are selected to be the spline interpolation point. And cubic spline interpolation according to the starting points is used to fit the baseline drift. Subsequently, pulse waveform of baseline drift removed is obtained by pulse wave data minus the corresponding baseline drift values. Results: Pulse waveforms after removing baseline drift are stable and have a minor relative error. Conclusion: The actual measurement results show that the method can inhibit the baseline drift effectively. The method and can be well applied in real-time detection of pulse wave.
Bioinformatics and Biomedical Engineering (iCBBE), 2010 4th International Conference on; 07/2010
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ABSTRACT: To explore the T cell-mediated immunopathogenesis of latent autoimmune diabetes in adults (LADA).
Seventeen LADA patients, 28 T2DM (type 2 diabetes mellitus) patients and 16 healthy controls were recruited. GAD-Ab, IA-2Ab and CPH-Ab were determined by radioligand assays. Human peripheral blood mononuclear cells were isolated by Ficoll-Hypaque density gradients. And the spot numbers of IFN-γ-secreting T cells (IFN-γ-Th1) and IL-4-secreting T cells (IL-4-Th2) were detected by enzyme linked immunospot (ELISPOT) assay. One spot-forming represented a GAD(65)-reactive IFN-γ/IL-4-secreting T cell. The ratio (balance) of Th1/Th2 was defined as IFN-γ-Th1/IL-4-Th2.
(1) The spot numbers of IFN-γ-Th1 (median) were 4.0, 2.0 and 1.0 in LADA, T2DM and control while those of IL-4-Th2 2.0, 3.3 and 1.0 and Th1/Th2 3.0, 0.4 and 0.3 respectively; (2) As compared to T2DM or control group, significant increases of Th1 (P < 0.01) and Th1/Th2(P < 0.05) were observed in LADA group. But the spot numbers of Th2 showed no significant differences among three groups (P > 0.05). And there were no differences of Th1 and Th1/Th2 between T2DM and control group (P > 0.05); (3) No significant difference of Th1 or Th2 was observed for phytohemagglutinin (PHA) stimulation in three groups (P > 0.05).
Significantly enhanced IFN-γ-Th1 cells and a shift of Th1/Th2 towards Th1 are present in LADA patients. They may contribute to the T-cell mediated immunopathogenesis of LADA.
Zhonghua yi xue za zhi 07/2010; 90(28):1963-5.
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ABSTRACT: To investigate the relation between insulin resistance and glutamic acid decarboxylase antibody (GAD-Ab) titers in latent autoimmune diabetes in adults (LADA).
The patients with phenotypic type 2 diabetes were screened for GAD-Ab positivity, and the 141 positive patients were divided into two subgroups according to the GAD-Ab titer, namely the high-titer group (LADA-1 subtype) and low-titer group (LADA-2 subgroup). The clinical features and insulin resistance were compared between the two groups. Insulin resistance was calculated by HOMA 2 software, and GAD-Ab and C peptide were determined with radioligand and radioimmune assay, respectively.
Compared with low-titer LADA patients, the patients with high titers had younger age of onset, lower BMI, higher HbA1c level, and worse fasting and postprandial C peptide levels. The insulin resistance index by HOMA 2 was significantly lower in LADA-1 group than in LADA-2 group (1.6-/+1.1 vs 2.1-/+1.1, P=0.001). The HOMA2-IR index showed a negative correlation to GAD-Ab titer.
The degree of insulin resistance is correlated to GAD-Ab titers in LADA, and low titer patients have higher insulin resistance level.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 06/2010; 30(6):1247-9.
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ABSTRACT: To explore the characteristics of T cell immunity in peripheral blood of patients with carboxypeptidase-H antibody (CPH-Ab).
Forty-two latent autoimmune diabetes in adults (LADA) patients with CPH-Ab(+) alone, 20 Type 2 diabetes mellitus patients (T2DM), and 22 healthy controls were selected and their peripheral blood mononuclear cells were isolated. Human recombinant carboxypeptidase (CPH) protein was expressed and further used as a stimulant in Enzyme-linked immunospot (ELISPOT) assay to detect IFN-gamma-Th1 and IL-4-Th2 cells in the 3 groups. Th1/Th2 ratios were also calculated. CPH-Ab and glutamic acid decarboxylase antibody (GAD-Ab) were determined by radioligand assay.
Compared with healthy controls and T2DM, IFN-gamma-Th1 and IL-4-Th2 numbers did not increase significantly in CPH-Ab(+) group, nor did the Th1/Th2 ratios (P>0.05). We further divided the CPH-Ab(+) patients into a short duration group (n=22) and a long duration subgroup (n=20) according to the duration of 3 years. CPH-IL-4-T in the short duration subgroup was significantly higher than that in T2DM and healthy controls (1.8 vs. 0.2 and 0.3, both P<0.05) and we did not find any factor that was significantly correlated with the IL-4 spots number. There were not any significant differences in T cell responses to phaseolus vulgaris agglutinin (PHA) among all groups (P>0.05).
CPH does not directly involve in the cellular pathological mechanism of LADA. Anti-CPH immunity may be associated with more slowly aggressive beta cell autoimmunity.
Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences 10/2009; 34(10):1011-6.
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ABSTRACT: To investigate the immunological features of fulminant type 1 diabetes.
Twenty patients with fulminant type 1 diabetes (F1D) were recruited based upon the criteria proposed by Hanafusa, and 40 patients with classical type 1 diabetes were matched with age, gender and duration for comparison. GADA, IA2A and ZnT8A were determined with radioligand assay, and GAD-reactive T cells were measured by enzyme-linked immunospot (ELISPOT) assay. The HLA-DQ were analyzed by sequence-based genotyping (SBT).
Eight of 20 patients with F1D were antibody-positive, including 7 GADA positive, 4 ZnT8A positive, and 3 both GADA and ZnT8A positive. The index of 3 GADA positive patients were less than 0.4 at first visit, two turned to be negative by two or three years. While the GADA index of the patient was 0.343 at onset and increased to 1.467 three years later. Among subjects with F1D (3/6) and classical type 1 diabetes (3/6), were recorded significant GAD-stimulated responses by ELISPOT assay. The frequencies of HLA-DQA1*0102-DQB1*0601 and DQA1*03-DQB1*0401 were significantly higher in F1D than those in classical type 1 diabetes (P = 0.005, P = 0.035, respectively).
Humoral and cellular immunoreactivity and susceptible HLA-DQ genotype existed in part of F1D patients, indicating autoimmunity may involve in the pathogenesis of F1D.
Zhonghua yi xue za zhi 09/2009; 89(36):2544-7.
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ABSTRACT: To investigate the immunological features and pancreatic beta cell function of first-degree relatives of latent autoimmune diabetes in adults (LADA).
Oral glucose tolerance test (OGTT) was performed in 209 first-degree relatives of LADA patients and 340 first-degree relatives of classic T1DM patients. Radioligand assay was used to detect glutamic acid decarboxylase antibody (GADAb) and protein tyrosine phosphatase antibody (IA-2Ab). Intravenous glucose tolerance tests were performed in 39 normal controls and 46 first-degree relatives. Among them, 9 were GAD-Ab positive and 9 GAD-Ab negative first-degree relatives of patients with LADA while 12 were GAD-Ab positive and 16 GAD-Ab negative first-degree relatives of patients with classic T1DM.
(1) Immunological characteristics of first-degree relatives of patients with LADA. Similar with the first-degree relatives of patients with classic T1DM (18/340, 5.3%), the detection rate of GAD-Ab was 4.3% (9/209) in first-degree relatives of patients with LADA. (2) Islet function of first-degree relatives of patients with LADA. Compared with the control group, the first phase insulin release and the first phase insulin peak secretion averages were lower in the antibody positive group of first-degree relatives of patients with LADA (P < 0.05); HOMA-IR was higher in the antibody negative group of first-degree relatives of patients with LADA (P < 0.05). (3) Analysis on glucose metabolism of different immune status for first-degree relatives of patients with LADA. (1) The detection rate of impaired glucose tolerance (IGT) was 16.7% (35/209) and diabetes (DM) rate 10.0% (21/209). (2) The detection rate of IGT was higher in the antibody positive group than the antibody negative group in first-degree relatives of patients with LADA (37.5% vs 15.0%, P < 0.05).
Among first-degree relatives of patients with LADA, a certain extent of islet autoimmune antibody markers could be measured, and insulin resistance and insulin secretion defects were detected. The rate of IGT was higher in the antibody positive group than the antibody negative group.
Zhonghua yi xue za zhi 07/2009; 89(26):1820-4.
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ABSTRACT: Altered Toll-like receptors (TLRs) expression and response of monocyte may be associated with insulin sensitivity, obesity and diabetes.
Peripheral blood monocytes were respectively collected from 23 healthy controls, 16 type 1 diabetes mellitus (T1DM), and 18 latent autoimmune diabetes in adults (LADA). CD14, TLR2 and TLR4 expression were analyzed by flow cytometer. Moreover, the effect of 1, 25-dihydroxy-vitamin D3 (1,25(OH)(2)D3) on monocyte response to lipoteichoic acid (LTA) and lipopolysaccharide (LPS) was evaluated in vitro by measuring phosphorylation concentration of NF-kappaB-p65 and associated cytokine production.
Monocytes showed significantly higher surface CD14 and TLR4 expressions from LADA and lower CD14 expression from T1DM than controls. TLRs ligands decreased monocyte CD14 expression in T1DM but increased in LADA. Monocyte hyperresponsiveness to ligands was modulated by 1,25(OH)(2)D3 to similar concentration, as compared to controls.
Monocytes from T1DM and LADA showed similar cellular reactivity towards ligands and 1,25(OH)2D3 was observed to restore this defect to a certain extent in vitro.
Clinica chimica acta; international journal of clinical chemistry 02/2009; 402(1-2):133-8. · 2.54 Impact Factor
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ABSTRACT: To investigate the differences of Toll-like receptors (TLRs) expression and response of monocyte and modulation of 1,25-dihydroxy-vitamin D3 on monocyte activity. Peripheral blood monocytes were collected from 23 healthy controls, 18 latent autoimmune diabetes in adults (LADA), and 22 type 2 diabetes mellitus (T2DM), respectively. CD14, TLR2 and TLR4 expression were analyzed. Moreover, the effect of 1,25-dihydroxy-vitamin D3 (1,25(OH)(2)D3) on monocyte response to lipoteichoic acid (LTA) and lipopolysaccharide (LPS) was evaluated in vitro by measuring phosphorylation level of NF-kappaB-p65 and associated cytokine production. Monocytes showed significantly higher surface CD14 expression from LADA compared with that from T2DM and controls, and high expression of TLR4 from LADA and T2DM than controls. After incubation with LPS or LTA, decreased surface expressions of CD14 were observed on monocytes from T2DM and controls, in contrast to the increased on monocytes from LADA. Activation of NF-kappaB and amounts of IL-1beta and TNF-alpha production by stimulation with ligands significantly increased in LADA and T2DM, which was modulated by 1,25(OH)(2)D3 to similar level, as compared to controls. The modulation of 1,25(OH)(2)D3 on monocytes makes us to consider more potency of vitamin D3 as therapy in LADA and T2DM.
Diabetes research and clinical practice 12/2008; 83(2):208-14. · 2.16 Impact Factor
