Identification of spectral biomarkers for type 1 diabetes mellitus using the combination of chiroptical and vibrational spectroscopy.

The current diagnostic tools are insufficient for the early detection of many diseases, including type 1 diabetes mellitus. The disease is accompanied not only by a permanently elevated level of blood glucose and altered levels of other biomarkers, but also by changes in the conformation of blood plasma proteins and other biomolecules associated with the pathogenesis of diabetes. However, the observation of these structural changes by conventional Raman and infrared spectroscopy is limited. Therefore, we used chiroptical spectroscopy which is inherently sensitive to the 3D structure of chiral molecules and able to detect any possible structural changes. We investigated the blood plasma samples of diabetic patients and healthy controls by Raman optical activity and electronic circular dichroism. The measurements were combined with conventional methods of molecular spectroscopy, i.e. Raman and infrared spectroscopy. The obtained data sets were statistically evaluated using linear discriminant analysis focusing on the spectral ranges that correspond to the structure and conformation of proteins and other plasmatic biomolecules. Our results suggest that chiroptical spectroscopy gives more detailed information about the 3D structure of biomolecules; and therefore, might be a promising complement to conventional diagnostic methods.

Anti-GAD65 reactive peripheral blood mononuclear cells in the pathogenesis of cystic fibrosis related diabetes mellitus.

OBJECTIVE: A role of autoreactive T cells for type 1 diabetes pathogenesis is considered crucial. In our pilot study we addressed if autoreactive mononuclear cells are present also in peripheral blood of patients with other specific forms of diabetes as cystic fibrosis related diabetes (CFRD). METHODS: Cellular immune responses to a known beta-cell autoantigen (GAD65 and GAD65 derived peptides) were analysed by ELISPOT (IFN-gamma) and by protein microarray analysis in four patients suffering from CFRD, in four cystic fibrosis (CF) patients without diabetes, in eight type 1 diabetes patients (without CF) and in four healthy controls. RESULTS: Response to the autoantigen GAD65 (protein and peptides) was observed in 7/8 patients suffering from CF and in all type 1 diabetes patients. Post-stimulation production of Th1 cytokines (IFN-gamma, TNF-beta) was observed in 2/4 CFRD, 1/4 CF patients and in 7/8 type 1 diabetes patients. All these patients carry prodiabetogenic HLA-DQ genotype. Th2- and Th3 type of cytokine pattern was observed in 2/4 CF patients. Production of IL-8 was observed in the third CFRD as well as in the third CF patient and in 1/8 type 1 diabetes patient and borderline production of this chemokine was also observed in 2/4 healthy controls. No reaction was observed in the other 2/4 healthy controls and in the fourth CFRD patient who carried a strongly protective genotype and did not produce autoantibodies. The most potent peptide of GAD65 was amino acids 509-528. CONCLUSIONS: We consider our observations as a sign of a reaction directed against the self-antigen GAD65 that are closely connected to type 1 diabetes. In CF patients who do not develop diabetes autoreactive mechanisms are very probably efficiently suppressed by immune self-tolerance mechanisms. CFRD patients are a heterogenic group. To disclose those who may display features of autoimmune diabetes could have an impact for their therapy and prognosis.

High prevalence of coeliac disease in siblings of children with type 1 diabetes.

UNLABELLED: Coeliac disease has been shown to occur more frequently among first-degree relatives of diabetic patients than in the general population. Our objective was to assess the prevalence of endomysium antibodies (EMA) in non-diabetic siblings of Czech diabetic children and to evaluate the effects of HLA-DQ polymorphisms in determining the genetic susceptibility to coeliac disease (CD) in these subjects. We investigated 240 siblings of diabetic children from 213 families (125 males and 115 females, aged 12.6+/-4.9 years, mean +/- SD). All subjects were tested for the total IgA level to exclude IgA deficiency, and for endomysium IgA to disclose CD. In five IgA-deficient subjects, anti-gliadin IgG was used instead. Small bowel biopsy was offered to subjects with confirmed positive EMA. The HLA-DQA1, -DQB1 genotypes were determined using PCR-SSP. Positive EMA were found in 9/240 (3.8%) subjects (three males, six females). The biopsy confirmed CD in six children, two had a normal mucosal finding and one refused the biopsy. The HLA-DQ2 polymorphism was more frequent among siblings with EMA (seven of nine) than in siblings without EMA (33%), corrected P = 0.031. CONCLUSION: The 3.8% frequency of coeliac disease found in siblings of diabetic children is close to the 4.3% found previously in Czech children with type 1 diabetes mellitus and is substantially higher than the rate in the healthy children population.

Association of single nucleotide polymorphisms within cytokine genes with juvenile idiopathic arthritis in the Czech population.

OBJECTIVE: To examine the possible association of juvenile idiopathic arthritis (JIA) with polymorphisms within cytokine genes in the Czech population. METHODS: In a case-control study, genotypes of 130 patients with JIA (63 male, 67 female; age at onset 7.6 +/- 4.4 yrs; 43 oligoarticular, 72 polyarticular, 15 systemic form) were compared to 102 healthy unrelated blood donors. Using the polymerase chain reaction technique with sequence-specific primers from the 13th IHWG workshop, we analyzed 19 single nucleotide polymorphisms within 12 different cytokine genes [interleukin (IL)-1a, IL-1beta, IL-2, IL-4, IL-6, IL-10, IL-12, transforming growth factor (TGF)-beta, interferon (IFN)-g], and related molecules (IL-1R, IL-1RA, IL-4Ra). Genotype frequencies were compared using chi-square analysis, and the significance level was corrected for the number of independent tests. RESULTS: Significant positive association was found for the G allele of the IL-4 -1098 T/G polymorphism, which was carried by 10% of cases and 25% of controls [odds ratio (OR) 0.32, 95% confidence interval (CI) 0.16-0.67, corrected p = 0.038). Also, a nonsignificant increase in the frequency of the IL-1beta +3962 C allele was detected in cases (96%) versus controls (84%) (OR 4.65, 95% CI 1.64-13.2, corrected p = 0.091). We did not replicate previously found associations with the IL-1a, IL-6, IL-10, and IL-1RA polymorphisms. CONCLUSION: Our study showed association with JIA for the IL-4 -1098 T/G polymorphism. It also underlines the genetic contribution of IL-1 polymorphisms to the pathogenesis of JIA, as another polymorphism within the IL-1beta may influence the risk of the disease.

NEUROD polymorphism Ala45Thr is associated with Type 1 diabetes mellitus in Czech children.

Association of the NEUROD Ala45Thr polymorphism with Type 1 diabetes mellitus (DM) has been found in some but not all populations. We performed a study on the association of two NEUROD exon 2 polymorphisms, the Ala45Thr and the Pro197His, with childhood-onset Type 1 DM in the Czech population. We compared 285 children with Type 1 DM diagnosed under the age of 15 years with 289 non-diabetic control children. The genotypes were determined using novel real-time allele-specific PCR assays in the TaqMan format, and data were analysed using logistic regression. The numbers of subjects with codon 45 genotypes Ala/Ala, Ala/Thr, Thr/Thr were 95, 145, 45 among cases and 117, 130, 42 among controls. Thr45 phenotypic positivity was associated with a significant risk of Type 1 DM (OR=2.01, CI 95% 1.25-3.24) in a multivariate logistic regression model involving also the insulin gene -23HphI genotype and the presence of Type 1 DM-associated HLA-DQB1*0302-DQA1*03 (DQ8) and DQB1*0201-DQA1*05 (DQ2) molecules. No association was observed for the Pro197His mutation which was carried by 5.3% cases and 5.9% controls. Our results confirm that the NEUROD Ala45Thr polymorphism is associated with childhood-onset Type 1 DM.

Anti-cyclic citrullinated peptide antibodies in patients with juvenile idiopathic arthritis.

We analysed the presence of anti-cyclic citrullinated peptide (anti-CCP) and anti-keratin (AKA) antibodies of the IgG class in sera of patients with defined juvenile idiopathic arthritis (JIA) of various subgroups with more than one year duration of the disease. Enzyme-linked immunosorbent assay (Immunoscan RA, Eurodiagnostica, The Netherlands) and an indirect immunofluorescence (IIF) test on rat oesophagus substrate (ImmuGloTM, Immco Diagnostics, Buffalo, USA) were used for the detection and quantification of anti-CCP and AKA antibodies in 140 patients with JIA (64 male and 76 female) aged 2-47 years (median 16.5 years). Overall, anti-CCP were found in 7/140 (5.0%) patients including 3/52 RF negative polyarthritis, 2/18 RF positive polyarthritis, 1/15 enthesitis related arthritis and 1/5 unclassifiable arthritis. AKA were detected in 40/140 patients (28.6%, p = 0.04) including 2/11 systemic arthritis, 2/32 oligoarthritis, 18/52 patients with RF negative polyarthritis (34.6%, p = 0.01), 14/18 RF positive polyarthritis (77.8%, p = 0.000002), 2/15 enthesitis related arthritis and 2/3 psoriatic arthritis. While simultaneous negativity for AKA and anti-CCP occurred in most (97/140; 69.3%) studied cases, simultaneous antibody positivity was found only in few (4/140; 2.9%) studied samples. We conclude that while AKA measured using IIF on rat esophagus can be detected approximately in one third of patients with definite JIA with more than 1 year duration of the disease, only rare occurrence of anti-CCP was observed. We conclude that AKA seem to be partly useful to confirm JIA diagnosis, however, useless to follow-up severity or activity in JIA patients. Anti-CCP do not have any additional value in MA cohort in comparison to RA where their diagnostic and prognostic importance was reported.