Vitamin D intake during the first 4 years and onset of asthma by age 5: A nested case-control study

BACKGROUND

Early-life vitamin D intake has been linked to asthma risk in childhood, but the role of longitudinal vitamin D exposure has not been previously evaluated. We investigated the association between vitamin D intake during the first 4 years of life and asthma risk by age 5.

METHODS

Within a Finnish population-based birth cohort, 182 incident asthma cases were matched to 728 controls on sex, genetic risk for type 1 diabetes, delivery hospital, and time of birth. Vitamin D intake was assessed by age-specific 3 day food records. Parents completed a validated version of the International Study of Asthma and Allergies in Childhood questionnaire at 5 years.

RESULTS

At 3 months, supplements were the main source of vitamin D intake; intake from foods increased from 3 months on, mainly from fortified milk products. Vitamin D intake at each specific age was associated with an increased risk of any asthma, atopic, and non-atopic asthma, but only intake at 1 and 2 years was statistically significantly associated with asthma. Longitudinal vitamin D intake was associated with an increased risk of asthma (OR 1.24; 95%CI 1.00-1.53).

CONCLUSIONS

Increased vitamin D intake in childhood, particularly intake at 1 and 2 years of age, may increase risk of childhood asthma. This might reflect a true effect or residual confounding by lifestyle or environmental factors. Repeated assessment of vitamin D intake allowed evaluation of the longitudinal and age-dependent impact of vitamin D on the risk of asthma. Further longitudinal studies are required to confirm or question these findings.

Imbalance of bacteriome profiles within the Finnish Diabetes Prediction and Prevention study: Parallel use of 16S profiling and virome sequencing in stool samples from children with islet autoimmunity and matched controls

BACKGROUND

We set out to explore associations between the stool bacteriome profiles and early-onset islet autoimmunity, taking into account the interactions with the virus component of the microbiome.

METHODS

Serial stool samples were longitudinally collected from 18 infants and toddlers with early-onset islet autoimmunity (median age 17.4 months) followed by type 1 diabetes, and 18 tightly matched controls from the Finnish Diabetes Prediction and Prevention (DIPP) cohort. Three stool samples were analyzed, taken 3, 6, and 9 months before the first detection of serum autoantibodies in the case child. The risk of islet autoimmunity was evaluated in relation to the composition of the bacteriome 16S rDNA profiles assessed by mass sequencing, and to the composition of DNA and RNA viromes.

RESULTS

Four operational taxonomic units were significantly less abundant in children who later on developed islet autoimmunity as compared to controls-most markedly the species of Bacteroides vulgatus and Bifidobacterium bifidum. The alpha or beta diversity, or the taxonomic levels of bacterial phyla, classes or genera, showed no differences between cases and controls. A correlation analysis suggested a possible relation between CrAssphage signals and quantities of Bacteroides dorei. No apparent associations were seen between development of islet autoimmunity and sequences of yet unknown origin.

CONCLUSIONS

The results confirm previous findings that an imbalance within the prevalent Bacteroides genus is associated with islet autoimmunity. The detected quantitative relation of the novel "orphan" bacteriophage CrAssphage with a prevalent species of the Bacteroides genus may exemplify possible modifiers of the bacteriome.

Avoidance of Cow's Milk-Based Formula for At-Risk Infants Does Not Reduce Development of Celiac Disease: A Randomized Controlled Trial

BACKGROUND & AIMS

Feeding during the first months of life might affect risk for celiac disease. Individuals with celiac disease or type 1 diabetes have been reported to have high titers of antibodies against cow's milk proteins. Avoidance of cow's milk-based formula for infants with genetic susceptibility for type 1 diabetes reduced the cumulative incidence of diabetes-associated autoantibodies. We performed a randomized controlled trial in the same population to study whether weaning to an extensively hydrolyzed formula reduced the risk of celiac disease autoimmunity or celiac disease.

METHODS

We performed a double-blind controlled trial of 230 infants with HLA-defined predisposition to type 1 diabetes and at least 1 family member with type 1 diabetes. The infants were randomly assigned to groups fed a casein hydrolysate formula (n = 113) or a conventional formula (control, n = 117) whenever breast milk was not available during the first 6-8 months of life. Serum samples were collected over a median time period of 10 years and analyzed for antibodies to tissue transglutaminase (anti-TG2A) using a radiobinding assay, to endomysium using an immunofluorescence assay, and antibodies to a deamidated gliadine peptide using an immunofluorometry assay. Duodenal biopsies were collected if levels of anti-TG2A exceeded 20 relative units. Cow's milk antibodies were measured during the first 2 years of life.

RESULTS

Of the 189 participants analyzed for anti-TG2A, 25 (13.2%) tested positive. Of the 230 study participants observed, 10 (4.3%) were diagnosed with celiac disease. We did not find any significant differences at the cumulative incidence of anti-TG2A positivity (hazard ratio, 1.14; 95% confidence interval, 0.51-2.54) or celiac disease (hazard ratio, 4.13; 95% confidence interval, 0.81-21.02) between the casein hydrolysate and cow's milk groups. Children who developed celiac disease had increased titers of cow's milk antibodies before the appearance of anti-TG2A or celiac disease.

CONCLUSIONS

In a randomized controlled trial of 230 infants with genetic risk factors for celiac disease, we did not find evidence that weaning to a diet of extensively hydrolyzed formula compared with cow's milk-based formula would decrease the risk for celiac disease later in life. Increased titers of cow's milk antibody before anti-TG2A and celiac disease indicates that subjects with celiac disease might have increased intestinal permeability in early life. ClinicalTrials.gov Number: NCT00570102.

Maternal fatty acid intake during pregnancy and the development of childhood overweight: a birth cohort study

BACKGROUND

Maternal diet during pregnancy may contribute to the risk of offspring adiposity.

OBJECTIVES

The objective of the study is to explore the associations between maternal antenatal dietary fatty acid intake and the risk of offspring overweight and obesity at the ages of 2 to 7 years.

METHODS

In a prospective Finnish birth cohort with 3807 mother-child pairs, maternal diet in late pregnancy was assessed with a food frequency questionnaire. Intakes of total fatty acids and individual saturated, monounsaturated and polyunsaturated fatty acids (PUFAs) were calculated. Generalized estimating equation models were used to study the associations of maternal dietary variables with repeatedly measured offspring overweight and obesity.

RESULTS

In girls, maternal intake ratio of n-6:n-3 PUFAs had a U-shaped association with obesity (adjusted OR for the lowest 2.0 [95% CI 1.27-3.20] and the highest 1.7 [1.03-2.73] vs. the two middle quartiles of n-6:n-3 PUFAs, p = 0.01). In boys, arachidonic acid (20:4n-6): docosahexaenoic acid + eicosapentaenoic acid ratio was associated with obesity (adjusted OR for the lowest 1.0 [0.60-1.57] and the highest 0.5 [0.26-0.88] vs. the two middle quartiles, p = 0.02). Saturated fatty acids and monounsaturated fatty acids were not associated with overweight or obesity in either sex.

CONCLUSIONS

Maternal intakes of PUFAs in late pregnancy were associated with risk of later obesity differently in girls and boys.

Fatty acid status in infancy is associated with the risk of type 1 diabetes-associated autoimmunity

AIMS/HYPOTHESIS

We investigated the association of early serum fatty acid composition with the risk of type 1 diabetes-associated autoimmunity. Our hypothesis was that fatty acid status during infancy is related to type 1 diabetes-associated autoimmunity and that long-chain n-3 fatty acids, in particular, are associated with decreased risk.

METHODS

We performed a nested case-control analysis within the Finnish Type 1 Diabetes Prediction and Prevention Study birth cohort, carrying HLA-conferred susceptibility to type 1 diabetes (n = 7782). Serum total fatty acid composition was analysed by gas chromatography in 240 infants with islet autoimmunity and 480 control infants at the age of 3 and 6 months. Islet autoimmunity was defined as repeated positivity for islet cell autoantibodies in combination with at least one of three selected autoantibodies. In addition, a subset of 43 infants with primary insulin autoimmunity (i.e. those with insulin autoantibodies as the first autoantibody with no concomitant other autoantibodies) and a control group (n = 86) were analysed. A third endpoint was primary GAD autoimmunity defined as GAD autoantibody appearing as the first antibody without other concomitant autoantibodies (22 infants with GAD autoimmunity; 42 infants in control group). Conditional logistic regression was applied, considering multiple comparisons by false discovery rate <0.05.

RESULTS

Serum fatty acid composition differed between breastfed and non-breastfed infants, reflecting differences in the fatty acid composition of the milk. Fatty acids were associated with islet autoimmunity (higher serum pentadecanoic, palmitic, palmitoleic and docosahexaenoic acids decreased risk; higher arachidonic:docosahexaenoic and n-6:n-3 acid ratios increased risk). Furthermore, fatty acids were associated with primary insulin autoimmunity, these associations being stronger (higher palmitoleic acid, cis-vaccenic, arachidonic, docosapentaenoic and docosahexaenoic acids decreased risk; higher α-linoleic acid and arachidonic:docosahexaenoic and n-6:n-3 acid ratios increased risk). Moreover, the quantity of breast milk consumed per day was inversely associated with primary insulin autoimmunity, while the quantity of cow's milk consumed per day was directly associated.

CONCLUSIONS/INTERPRETATION

Fatty acid status may play a role in the development of type 1 diabetes-associated autoimmunity. Fish-derived fatty acids may be protective, particularly during infancy. Furthermore, fatty acids consumed during breastfeeding may provide protection against type 1 diabetes-associated autoimmunity. Further studies are warranted to clarify the independent role of fatty acids in the development of type 1 diabetes.

Eliminating cows' milk, but not wheat, barley or rye, increases the risk of growth deceleration and nutritional inadequacies

AIM

Our study examined the growth and nutritional intake of children on milk and/or wheat, barley or rye elimination diets.

METHODS

This was a nested case-control study within the Finnish Type 1 Diabetes Prediction and Prevention Study. It investigated 295 children born in the Tampere University Hospital area between 1997 and 2004 on a diet without cows' milk and/or wheat, barley or rye due to food allergies and 265 matched controls. Nutritional intake was recorded with three-day food records at the ages of one, two and three years. Serial growth measurements were recorded annually up to the age of five years.

RESULTS

Despite consuming a balanced diet with sufficient energy and protein, the children on milk elimination diets grew slower than the control children (p = 0.009). Wheat, barley or rye elimination was not associated with growth. The intakes of protein and calcium were lower in children in the milk elimination group than the controls, at p < 0.05 for all. However, children on elimination diets consumed less saturated fats and sugar and more vitamin C and iron than the control children.

CONCLUSION

Children on elimination diets faced an increased risk of growth deceleration and suboptimal intake of several micronutrients.

Characterisation of rapid progressors to type 1 diabetes among children with HLA-conferred disease susceptibility

AIMS/HYPOTHESIS

In this study, we aimed to characterise rapid progressors to type 1 diabetes among children recruited from the general population, on the basis of HLA-conferred disease susceptibility.

METHODS

We monitored 7410 HLA-predisposed children participating in the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) study for the development of beta cell autoimmunity and type 1 diabetes from birth over a median follow-up time of 16.2 years (range 0.9-21.1 years). Islet cell antibodies (ICA) and autoantibodies to insulin (IAA), GAD (GADA) and islet antigen 2 (IA-2A) were assessed as markers of beta cell autoimmunity. Rapid progression was defined as progression to clinical type 1 diabetes within 1.5 years of autoantibody seroconversion. We analysed the association between rapid progression and demographic and autoantibody characteristics as well as genetic markers, including 25 non-HLA SNPs predisposing to type 1 diabetes.

RESULTS

Altogether, 1550 children (21%) tested positive for at least one diabetes-associated autoantibody in at least two samples, and 248 (16%) of seroconverters progressed to type 1 diabetes by the end of 2015. The median time from seroconversion to diagnosis was 0.51 years in rapid progressors (n = 42, 17%) and 5.4 years in slower progressors. Rapid progression was observed both among young (<5 years) and early pubertal children (>7 years), resulting in a double-peak distribution of seroconversion age. Compared with slower progressors, rapid progressors had a higher frequency of positivity for multiple (≥2) autoantibodies and had higher titres of ICA, IAA and IA-2A at seroconversion, and there was a higher prevalence of the secretor genotype in the FUT2 gene among those carrying the high-risk HLA genotype. Compared with autoantibody-positive non-progressors, rapid progressors were younger, were more likely to carry the high-risk HLA genotype and a predisposing SNP in the PTPN22 gene, had higher frequency of ICA, IAA, GADA and IA-2A positivity and multipositivity, and had higher titres of all four autoantibodies at seroconversion.

CONCLUSIONS/INTERPRETATION

At seroconversion, individuals with rapid progression to type 1 diabetes were characterised by a younger age, higher autoantibody titres, positivity for multiple autoantibodies and higher prevalence of a FUT2 SNP. The double-peak profile for seroconversion age among the rapid progressors demonstrates for the first time that rapid progression may take place not only in young children but also in children in early puberty. Rapid progressors might benefit from careful clinical follow-up and early preventive measures.

A drop in the circulating concentrations of soluble receptor for advanced glycation end products is associated with seroconversion to autoantibody positivity but not with subsequent progression to clinical disease in children en route to type 1 diabetes

BACKGROUND

Advanced glycation end products (AGEs) and their interaction with the receptor for AGEs (RAGE) have been studied for their role in the pathogenesis and complications of type 1 diabetes. Decreased concentrations of soluble RAGE (sRAGE) have been reported in acute autoimmune inflammation. We set out to analyze the changes in sRAGE concentration during preclinical diabetes in children seroconverting to islet autoantibody positivity.

METHODS

We measured serum concentrations of sRAGE in 168 children who progressed to clinical disease and 43 children who turned positive for at least 2 diabetes-associated autoantibodies but remained nondiabetic. We analyzed the sRAGE before seroconversion in the first autoantibody-positive sample and annually thereafter until the diagnosis of type 1 diabetes or end of follow-up.

RESULTS

Both groups had similar sRAGE before seroconversion, but subsequently, sRAGE concentrations were lower (P < .001) in the progressors. The progressors had significantly higher sRAGE concentrations before than after seroconversion (P < .001). The nonprogressors did not experience a similar decrease. The sRAGE concentrations remained stable after seroconversion in both groups.

CONCLUSIONS

These data indicate that sRAGE may be involved in the initiation of beta-cell autoimmunity but not in the progression from beta-cell autoimmunity to clinical disease.

Detection of enteroviruses in stools precedes islet autoimmunity by several months: possible evidence for slowly operating mechanisms in virus-induced autoimmunity

AIMS/HYPOTHESIS

This case-control study was nested in a prospective birth cohort to evaluate whether the presence of enteroviruses in stools was associated with the appearance of islet autoimmunity in the Type 1 Diabetes Prediction and Prevention study in Finland.

METHODS

Altogether, 1673 longitudinal stool samples from 129 case children who turned positive for multiple islet autoantibodies and 3108 stool samples from 282 matched control children were screened for the presence of enterovirus RNA using RT-PCR. Viral genotype was detected by sequencing.

RESULTS

Case children had more enterovirus infections than control children (0.8 vs 0.6 infections per child). Time-dependent analysis indicated that this excess of infections occurred more than 1 year before the first detection of islet autoantibodies (6.3 vs 2.1 infections per 10 follow-up years). No such difference was seen in infections occurring less than 1 year before islet autoantibody seroconversion or after seroconversion. The most frequent enterovirus types included coxsackievirus A4 (28% of genotyped viruses), coxsackievirus A2 (14%) and coxsackievirus A16 (11%).

CONCLUSIONS/INTERPRETATION

The results suggest that enterovirus infections diagnosed by detecting viral RNA in stools are associated with the development of islet autoimmunity with a time lag of several months.

The association of the HLA-A*24:02, B*39:01 and B*39:06 alleles with type 1 diabetes is restricted to specific HLA-DR/DQ haplotypes in Finns

BACKGROUND

We analysed the previously reported association of the HLA-A*24:02, B*18 and B*39 alleles with type 1 diabetes and diabetes associated autoimmunity in the Finnish population applying HLA-DR/DQ stratification.

MATERIALS & METHODS

Haplotype transmission was analysed in 2424 nuclear families from the Finnish Paediatric Diabetes Register. Survival analysis was applied to study the development of islet autoantibodies and further progression to clinical diabetes in the prospective follow-up cohort from the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Study. The subjects were genotyped for specific HLA class I alleles by sequence-specific hybridization using lanthanide labelled nucleotide probes.

RESULTS

The HLA-B*39:06 allele was found almost exclusively on the (DR8)-DQB1*04 haplotype in which its presence changed the disease risk status of the whole haplotype from neutral to predisposing. The HLA-A*24:02 and the B*39:01 alleles increased the diabetes-associated risk of the DRB1*04:04-DQA1*03-DQB1*03:02 haplotype but the alleles were in linkage disequilibrium and no independent effect could be detected. Within the DIPP cohort, neither the A*24:02 nor the B*39:01 allele were associated with seroconversion but were in contrast associated with increased progression from seroconversion to clinical disease.

DISCUSSION & CONCLUSIONS

The independent predisposing effect of the HLA-B*39:06 allele with type 1 diabetes was confirmed in the Finnish population but the association of the A*24:02 and B*39:01 alleles remained inconclusive whilst both A*24:02 and B*39:01 affected the progression rate from seroconversion to autoantibody positivity to overt type 1 diabetes.

Circulating CXCR5+PD-1+ICOS+ Follicular T Helper Cells Are Increased Close to the Diagnosis of Type 1 Diabetes in Children With Multiple Autoantibodies

Although type 1 diabetes (T1D) is primarily perceived as a T cell-driven autoimmune disease, islet autoantibodies are the best currently available biomarker for autoimmunity and disease risk. These antibodies are produced by autoreactive B cells, the activation of which is largely dependent on the function of CD4⁺CXCR5⁺ follicular T helper cells (Tfh). In this study, we have comprehensively characterized the Tfh- as well as B-cell compartments in a large cohort of children with newly diagnosed T1D or at different stages of preclinical T1D. We demonstrate that the frequency of CXCR5⁺PD-1⁺ICOS⁺-activated circulating Tfh cells is increased both in children with newly diagnosed T1D and in autoantibody-positive at-risk children with impaired glucose tolerance. Interestingly, this increase was only evident in children positive for two or more biochemical autoantibodies. No alterations in the circulating B-cell compartment were observed in children with either prediabetes or diabetes. Our results demonstrate that Tfh activation is detectable in the peripheral blood close to the presentation of clinical T1D but only in a subgroup of children identifiable by positivity for multiple autoantibodies. These findings suggest a role for Tfh cells in the pathogenesis of human T1D and carry important implications for targeting Tfh cells and/or B cells therapeutically.

Exploring the risk factors for differences in the cumulative incidence of coeliac disease in two neighboring countries: the prospective DIABIMMUNE study

BACKGROUND

During the last several decades the prevalence of coeliac disease (CD) has increased worldwide.

AIM

To compare the cumulative incidence of CD between Estonian and Finnish children and to identify the risk factors.

MATERIALS AND METHODS

Children were recruited as part of the DIABIMMUNE Study. In the birth cohort (BC) 258 children from Estonia and 305 from Finland, and in the young children's cohort (YCC) 1363 and 1384 children were followed up, respectively. The diagnosis of CD was made in accordance with the ESPGHAN guidelines-the presence of IgA-tTG antibodies and small bowel villous atrophy.

RESULTS

During the study period 29 children developed CD. The cumulative incidence of CD was significantly higher in Finland (0.77% vs 0.27%; P=0.01). No difference was seen between the children with CD and the controls in the duration of breastfeeding or the age at cereal introduction. The BC children with CD had had significantly more episodes of infections with fever by the age of 12 months compared to the controls (3.4 vs 1.4; P=0.04).

CONCLUSION

The 5-year cumulative incidence of childhood CD is significantly higher in Finland than in Estonia. Sequential infections early in life may increase the risk for developing CD.

Human enterovirus and rhinovirus infections are associated with otitis media in a prospective birth cohort study

BACKGROUND

Human enteroviruses (HEVs) and rhinoviruses (HRVs) have been linked to acute otitis media (AOM).

OBJECTIVES

The present study evaluates the aforementioned association in a birth cohort setting.

STUDY DESIGN

The cohort included 286 healthy infants (191 boys) followed from birth up to the age of 2 years in the Type 1 Diabetes Prediction and Prevention study in Finland. Stool samples were collected monthly and analyzed for the presence of HRV and HEV RNA using RT-PCR. Clinical symptoms were recorded by a questionnaire every 3-6 months.

RESULTS

Altogether 610 AOM episodes were reported during the follow-up. 9.8% of the stool samples were positive for HRV and 6.8% for HEV. HRV positivity peaked at the age of 3-6 months declining gradually after this age, whereas HEV positivity peaked later, at the age of 12-24 months. The risk of AOM was increased in children who were HEV positive at least once at the age of 6-12 months (OR 2.2 [95%CI 1.1-4.2], P=0.023) or who were HRV positive at least once at the age of 18-24 months (OR 2.3 [95%CI 1.0-5.2], P=0.042). Having an older sibling, short breast-feeding and maternal smoking during pregnancy were also significantly associated with AOM.

CONCLUSIONS

HRV and HEV infections are frequent during the first months of life. The observed trend for increased risk of AOM in HRV and HEV positive children is in line with the results from hospital series suggesting that these viruses may play an independent role in the pathogenesis of AOM.

Continuous glucose monitoring and HbA1c in the evaluation of glucose metabolism in children at high risk for type 1 diabetes mellitus

AIMS

Continuous glucose monitoring (CGM) parameters, self-monitored blood glucose (SMBG), HbA1c and oral glucose tolerance test (OGTT) were studied during preclinical type 1 diabetes mellitus.

METHODS

Ten asymptomatic children with multiple (⩾2) islet autoantibodies (cases) and 10 age and sex-matched autoantibody-negative controls from the Type 1 Diabetes Prediction and Prevention (DIPP) Study were invited to 7-day CGM with Dexcom G4 Platinum Sensor. HbA1c and two daily SMBG values (morning and evening) were analyzed. Five-point OGTTs were performed and carbohydrate intake was assessed by food records. The matched pairs were compared with the paired sample t-test.

RESULTS

The cases showed higher mean values and higher variation in glucose levels during CGM compared to the controls. The time spent ⩾7.8mmol/l was 5.8% in the cases compared to 0.4% in the controls (p=0.040). Postprandial CGM values were similar except after the dinner (6.6mmol/l in cases vs. 6.1mmol/l in controls; p=0.023). When analyzing the SMBG values higher mean level, higher evening levels, as well as higher variation were observed in the cases when compared to the controls. HbA1c was significantly higher in the cases [5.7% (39mmol/mol) vs. 5.3% (34mmol/mol); p=0.045]. No differences were observed in glucose or C-peptide levels during OGTT. Daily carbohydrate intake was slightly higher in the cases (254.2g vs. 217.7g; p=0.034).

CONCLUSIONS

Glucose levels measured by CGM and SMBG are useful indicators of dysglycemia during preclinical type 1 diabetes mellitus. Increased evening glucose values seem to be common in children with preclinical type 1 diabetes mellitus.

Immunological Reconstitution in Children After Completing Conventional Chemotherapy of Acute Lymphoblastic Leukemia is Marked by Impaired B-cell Compartment

Humoral and cellular immunity were studied in 28 children completing conventional treatment of standard-risk (SR) or intermediate-risk (IR) acute lymphoblastic leukemia (ALL). Both naïve and memory B cells were most severely affected and showed slow recovery during the 2-year follow-up, while the T-cell compartment showed only minor changes. Immunoglobulins and IgG subclasses, components, and antibodies against vaccine-preventable diseases were not significantly affected. In conclusion, immune recovery after conventional chemotherapy for SR and IR ALL is marked by B-cell depletion, but otherwise did not show any severe deficiencies in lymphocyte function.

Development of gliadin-specific immune responses in children with HLA-associated genetic risk for celiac disease

OBJECTIVE

The development of gliadin-specific antibody and T-cell responses were longitudinally monitored in young children with genetic risk for celiac disease (CD).

MATERIAL AND METHODS

291 newborn children positive for HLA-DQB1*02 and -DQA1*05 alleles were followed until 3-4 years of age by screening for tissue transglutaminase autoantibodies (tTGA) by using a commercial ELISA-based kit and antibodies to deamidated gliadin peptide (anti-DGP) by an immunofluorometric assay. Eighty-five of the children were also followed for peripheral blood gliadin-specific CD4(+) T-cell responses by using a carboxyfluorescein diacetate succinimidyl ester-based in vitro proliferation assay.

RESULTS

The cumulative incidence of tTGA seropositivity during the follow-up was 6.5%. CD was diagnosed in nine of the tTGA-positive children (3.1%) by duodenal biopsy at a median 3.5 years of age. All of the children with confirmed CD were both IgA and IgG anti-DGP positive at the time of tTGA seroconversion and in over half of the cases IgG anti-DGP positivity even preceded tTGA seroconversion. Peripheral blood T-cell responses to deamidated and native gliadin were detected in 40.5% and 22.2% of the children at the age of 9 months and these frequencies decreased during the follow-up to the levels of 22.2% and 8.9%, respectively.

CONCLUSIONS

Anti-DGP antibodies may precede tTGA seroconversion and thus frequent monitoring of both tTGA and anti-DGP antibodies may allow earlier detection of CD in genetically susceptible children. Peripheral blood gliadin-specific T-cell responses are relatively common in HLA-DQ2-positive children and are not directly associated with the development of CD.

Clinical, Genetic, and Biochemical Characteristics of Early-Onset Diabetes in the Finnish Population

CONTEXT

Major advances have been made in the classification and genetics of monogenic diabetes in infancy.

OBJECTIVE

The objective of the study was to characterize different forms of diabetes diagnosed during the first year of life.

DESIGN

Patients diagnosed with diabetes before the age of 1 year in 10 Finnish hospitals from 1980 to 2014 were included.

SETTING

The study was conducted at Kuopio University Hospital and University of Eastern Finland.

PATIENTS

Patients were identified through diagnosis-based searches from hospital registries including 93 children, of whom 64 participated.

INTERVENTIONS

DNA sample for sequencing, serum sample, and medical records interventions were included.

MAIN OUTCOME MEASURES

Incidence of diabetes during the first year of life, sequencing results, human leukocyte antigen (HLA) genotypes, and islet autoantibodies were measured.

RESULTS

The incidence of diabetes diagnosed during the first 12 months was 4.4/100 000/year. Three novel and 11 previously described mutations were found in 22 patients from 15 families in the KCNJ11, ABCC8, INS, GCK, FOXP, STAT3, and RFX6 genes. Positive islet autoantibodies were observed in 40.0% of the patients diagnosed during the first 0-6 months of life vs 70.8% of the patients diagnosed between ages of 7 to 12 months. A total of 85.7% of the patients carrying protective HLA genotypes were mutation-positive compared to 7.7% of the patients having high-risk genotypes (P = .001).

CONCLUSIONS

Mutations in the K-ATP channel and INS genes were the most common cause of early diagnosed monogenic diabetes. After 6 months of age, patients with diabetes had high HLA risk genotypes and islet autoantibodies, reflecting the autoimmune character of diabetes in that age group.

Interleukin-10 gene promoter region polymorphisms are not associated with BCG osteitis in vaccinated infants

SETTING

Complications arising from bacille Calmette-Guérin (BCG) vaccination were recorded in a national register in Finland until 1988. In the period 1960-1988, 222 patients suffered from BCG osteitis.

OBJECTIVE

To evaluate whether single nucleotide polymorphisms (SNPs) in the promoter region of the gene encoding interleukin 10 (IL-10) are associated with BCG osteitis after vaccination in neonates.

DESIGN

Blood samples of 132 former BCG osteitis patients now aged 21-49 years were analysed in a controlled study for IL10 rs1800896 (-1082G/A), rs1800871 (-819C/T), rs1800872 (-592C/A) and rs1800890 (-3575T/A) polymorphisms.

RESULTS

The frequencies of genotypes of IL10 rs1800896, rs1800871, rs1800872 and rs1800890, the frequencies of variant genotypes and the frequencies of major or minor alleles did not differ between patients and controls. Furthermore, the frequencies of the eight possible combinations of the three IL10 alleles located close to each other (IL10 rs1800896, IL10 rs1800871 and IL10 rs1800872) were surprisingly similar.

CONCLUSION

Our results suggest that polymorphisms of the IL-10 encoding gene do not play a central role in the development of complications due to BCG vaccination, although the IL10 gene, especially IL10 rs1800896 (-1082G/A) polymorphism, is known to be associated with tuberculosis risk in Europeans and North Americans.

Role of humoral beta-cell autoimmunity in type 1 diabetes

Islet cell antibodies (ICA) were found for the first time more than 40 yr ago in patients with autoimmune endocrine deficiencies, including type 1 diabetes (T1D). ICA detected by indirect immunofluorescence represent a heterogeneous group of autoantibodies targeting a series of biochemical autoantigens, such as the protein tyrosine phosphatase related islet antigen 2 (IA-2), the 65 kD isoform of glutamic acid decarboxylase (GA65), and zinc transporter 8 (ZnT8) as well as currently unidentified autoantigens. The general view is that the diabetes-associated autoantibodies are not directly involved in beta-cell destruction but function as biomarkers of an ongoing destructive process. The diabetes-associated autoantibodies remain the strongest predictive marker for future development of T1D. Positivity for multiple (≥2) autoantibodies is highly predictive of clinical disease both among first-degree relatives and in the general population. Autoantibody titers are highly variable during the preclinical phase, but in many cases the titers tend to decrease before diagnosis. The first signs of beta-cell autoimmunity may appear early during the first months of life. The majority of those individuals diagnosed with T1D before puberty seroconvert to autoantibody positivity before the age of 3 yr. The natural course and duration of preclinical diabetes vary substantially from one individual to another. The characteristics of the isotype-specific response during preclinical diabetes appear to be antigen-specific. Diabetes-associated autoantibodies may be useful surrogate markers of the subsequent development of T1D in primary prevention trials. T1D may occur, albeit rarely, in the absence of any signs of humoral autoimmunity at diagnosis.

Genetic susceptibility to type 1 diabetes in childhood - estimation of HLA class II associated disease risk and class II effect in various phases of islet autoimmunity

OBJECTIVE

The HLA-DR/DQ region remains the major determinant of susceptibility to type 1 diabetes (T1D) despite the more than 50 risk affecting loci outside human leukocyte antigen (HLA) region that have been identified. We aimed at developing a simple risk estimation based on HLA class II genotyping, which was also tested by analyzing HLA class II effect on the autoantibody seroconversion and further progression to diabetes.

SUBJECTS AND METHODS

A total of 2991 trio families with a diabetic child from the Finnish Pediatric Diabetes Register were genotyped and the risk contributed by each DR-DQ haplotype calculated through transmission analysis. The genotype risk was estimated based on the summary effect of haplotypes. Genotype grouping was further tested in a subcohort of the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Study

RESULTS

The summary effect of haplotypes was generally seen in genotypes, while the expected synergistic effect of DR3-DQ2 and DR4-DQ8 (DRB1*04:03 excluded) combination was also clear in the T1D risk association analysis. This highest risk DR/DQ genotype was found in 21.6% of patients and 2.0% of controls, odds ratio (OR) = 13.2 (10.1-17.2), whereas the lowest risk genotype contained only 0.8% of patients and 28.0% of controls, OR = 0.02 (0.01-0.03). In the subcohort from the DIPP study the risk grades correlated clearly with seroconversion for islet autoantibodies and T1D development. In contrast, DR/DQ risk groups did not associate with the progression rate from advanced autoimmunity to clinical diabetes.

CONCLUSIONS

Class II HLA genotype groups improve the estimation of T1D risk. Class II effect is limited to the early phase of the disease process characterized by seroconversion for islet autoantibodies.

Complement gene variants in relation to autoantibodies to beta cell specific antigens and type 1 diabetes in the TEDDY Study

A total of 15 SNPs within complement genes and present on the ImmunoChip were analyzed in The Environmental Determinants of Diabetes in the Young (TEDDY) study. A total of 5474 subjects were followed from three months of age until islet autoimmunity (IA: n = 413) and the subsequent onset of type 1 diabetes (n = 115) for a median of 73 months (IQR 54-91). Three SNPs within ITGAM were nominally associated (p < 0.05) with IA: rs1143678 [Hazard ratio; HR 0.80; 95% CI 0.66-0.98; p = 0.032], rs1143683 [HR 0.80; 95% CI 0.65-0.98; p = 0.030] and rs4597342 [HR 1.16; 95% CI 1.01-1.32; p = 0.041]. When type 1 diabetes was the outcome, in DR3/4 subjects, there was nominal significance for two SNPs: rs17615 in CD21 [HR 1.52; 95% CI 1.05-2.20; p = 0.025] and rs4844573 in C4BPA [HR 0.63; 95% CI 0.43-0.92; p = 0.017]. Among DR4/4 subjects, rs2230199 in C3 was significantly associated [HR 3.20; 95% CI 1.75-5.85; p = 0.0002, uncorrected] a significance that withstood Bonferroni correction since it was less than 0.000833 (0.05/60) in the HLA-specific analyses. SNPs within the complement genes may contribute to IA, the first step to type 1 diabetes, with at least one SNP in C3 significantly associated with clinically diagnosed type 1 diabetes.

Polymorphism of IL-10 gene promoter region: association with T cell proliferative responses after acellular pertussis vaccination in adults

Individual variation in immune responses is always encountered after vaccination. This phenomenon is also seen after acellular pertussis vaccination. The aim of this present study was to investigate whether single nucleotide polymorphisms (SNPs) in the IL-10 gene promoter region (rs1800890, rs1800896, rs1800871), IL-12B (rs2546890), IL-12RB1 (rs372889), IL-17A (rs2275913), and IL-23R (rs11209026) affect the immune responses after acellular pertussis vaccination. The T cell proliferative response was evaluated in 38 Finnish young adults who received a second booster dose of a vaccine combination of diphtheria, tetanus, and acellular pertussis, 10 years after the previous booster. The response was evaluated with a proliferation assay in which vaccine antigens pertussis toxin (PT), filamentous hemagglutinin (FHA), and pertactin (PRN) were used for the stimulation, before and 1 month after the second vaccination. Specific proliferation of peripheral blood mononuclear cells against pertussis antigens was affected by IL-10 SNP in the promoter region at position -1082 (A>G, rs1800896). One month after the vaccination, subjects with the AA and AG genotypes had a significantly higher T cell proliferative response against PT and FHA compared to those with the GG genotype. Subjects with the GG genotype had the lowest responses. As a conclusion, our preliminary results indicate that IL-10 SNP -1082 might play an important role in T cell-mediated immune responses after acellular pertussis vaccination.