Gut Inflammation Markers, Diet, and Risk of Islet Autoimmunity in Finnish Children - A Nested Case-Control Study.

BACKGROUND: Gut dysbiosis and increased intestinal permeability have been reported to precede type 1 diabetes-related autoimmunity. The role of gut inflammation in autoimmunity is not understood. OBJECTIVES: This study aimed to assess whether gut inflammation markers are associated with risk of islet autoimmunity and whether diet is associated with gut inflammation markers. METHODS: A nested case-control sample of 75 case children with islet autoimmunity and 88 control children was acquired from the Finnish Type 1 Diabetes Prediction and Prevention cohort. Diet was assessed with 3-d food records, and calprotectin and human ß-defensin-2 (HBD-2) were analyzed from stool samples at 6 and 12 mo of age. Conditional logistic regression analysis was used in a matched case-control setting to assess risk of autoimmunity. Analysis of variance, independent samples t test, and a general linear model were used in secondary analyses to test associations of background characteristics and dietary factors with inflammation markers. RESULTS: In unadjusted analyses, calprotectin was not associated with risk of islet autoimmunity, whereas HBD-2 in the middle (odds ratio [OR]: 3.23; 95% confidence interval [CI]: 1.03, 10.08) or highest tertile (OR: 3.02; 95% CI: 1.05, 8.69) in comparison to the lowest at 12 mo of age showed borderline association (P-trend = 0.063) with higher risk of islet autoimmunity. Excluding children with cow milk allergy in sensitivity analyses strengthened the association of HBD-2 with islet autoimmunity, whereas adjusting for dietary factors and maternal education weakened it. At age 12 mo, higher fat intake was associated with higher HBD-2 (ß: 0.219; 95% CI: 0.110, 0.328) and higher intake of dietary fiber (ß: -0.294; 95% CI: -0.510, -0.078), magnesium (ß: -0.036; 95% CI: -0.059, -0.014), and potassium (ß: -0.003; 95% CI: -0.005, -0.001) with lower HBD-2. CONCLUSIONS: Higher HBD-2 in infancy may be associated with higher risk of islet autoimmunity. Dietary factors play a role in gut inflammatory status.

Safety, tolerability and immunogenicity of PRV-101, a multivalent vaccine targeting coxsackie B viruses (CVBs) associated with type 1 diabetes: a double-blind randomised placebo-controlled Phase I trial.

AIMS/HYPOTHESIS: Infection with coxsackie B viruses (CVBs) can cause diseases ranging from mild common cold-type symptoms to severe life-threatening conditions. CVB infections are considered to be prime candidates for environmental triggers of type 1 diabetes. This, together with the significant disease burden of acute CVB infections and their association with chronic diseases other than diabetes, has prompted the development of human CVB vaccines. The current study evaluated the safety and immunogenicity of the first human vaccine designed against CVBs associated with type 1 diabetes in a double-blind randomised placebo-controlled Phase I trial. METHODS: The main eligibility criteria for participants were good general health, age between 18 and 45 years, provision of written informed consent and willingness to comply with all trial procedures. Treatment allocation (PRV-101 or placebo) was based on a computer-generated randomisation schedule and people assessing the outcomes were masked to group assignment. In total, 32 participants (17 men, 15 women) aged 18-44 years were randomised to receive a low (n=12) or high (n=12) dose of a multivalent, formalin-inactivated vaccine including CVB serotypes 1-5 (PRV-101), or placebo (n=8), given by intramuscular injections at weeks 0, 4 and 8 at a single study site in Finland. The participants were followed for another 24 weeks. Safety and tolerability were the primary endpoints. Anti-CVB IgG and virus-neutralising titres were analysed using an ELISA and neutralising plaque reduction assays, respectively. RESULTS: Among the 32 participants (low dose, n=12; high dose, n=12; placebo, n=8) no serious adverse events or adverse events leading to study treatment discontinuation were observed. Treatment-emergent adverse events considered to be related to the study drug occurred in 37.5% of the participants in the placebo group and 62.5% in the PRV-101 group (injection site pain, headache, injection site discomfort and injection site pruritus being most common). PRV-101 induced dose-dependent neutralising antibody responses against all five CVB serotypes included in the vaccine in both the high- and low-dose groups. Protective titres ≥8 against all five serotypes were seen in >90% of participants over the entire follow-up period. CONCLUSIONS/INTERPRETATION: The results indicate that the tested multivalent CVB vaccine is well tolerated and immunogenic, supporting its further clinical development. TRIAL REGISTRATION: ClinicalTrials.gov NCT04690426. FUNDING: This trial was funded by Provention Bio, a Sanofi company.

Serum 25-hydroxyvitamin D and fatty acids in relation to the risk of microbial infections in children: The TRIGR Divia study.

BACKGROUND & AIMS: Nutrient status may affect the risk of microbial infections and play a role in modulating the immune response against such infections. The aim of this study was to determine whether serum 25-hydroxyvitamin D [25(OH)D] and serum fatty acids in infancy are associated with microbial infections by the age of 18 months. METHODS: Altogether 576 newborn infants from Trial to Reduce IDDM in the Genetically at Risk (TRIGR) born between 2002 and 2007 were included. The concentration of 25(OH)D vitamin and proportions of 26 fatty acids (presented as % of total fatty acids) were analyzed in cord blood serum and in sera taken at 6, 12, and 18 months of age. The cord blood samples and mean of 6-18-month values were used as exposures. Infections were detected by screening IgG antibodies against 10 microbes using enzyme immunoassay and antibodies against 6 coxsackievirus B serotypes by plaque neutralization assay in serum samples taken at 18 months of age. RESULTS: A higher proportion of n-3 polyunsaturated fatty acids (PUFAs) and especially long-chain n-3 PUFAs at birth and at the age of 6-18 months was associated with decreased risk of coxsackievirus B2 infection unadjusted and adjusted for region, case-control status, and maternal type 1 diabetes. Higher proportion of docosapentaenoic acid (DPA, 22:5 n-3) at birth was associated with a decreased risk of respiratory syncytial virus infection. 25(OH)D vitamin concentration was not consistently associated with the risk of infections. When only infected children were included docosahexaenoic acid (DHA, 22:6 n-3) and arachidonic acid (20:4 n-6) proportions were positively associated with IgG antibody levels against influenza A virus. 25(OH)D vitamin concentration showed an inverse association with rotavirus IgG levels among children with rotavirus seropositivity. CONCLUSIONS: In young children with increased susceptibility to type 1 diabetes, long-chain n-3 PUFAs may influence the risk of viral infections and immune response against the infections. However, this association may depend on the type of virus suggesting virus-specific effects.

Exposomic determinants of immune-mediated diseases: Special focus on type 1 diabetes, celiac disease, asthma, and allergies: The HEDIMED project approach.

The incidence of immune-mediated diseases (IMDs) is increasing rapidly in the developed countries constituting a huge medical, economic, and societal challenge. The exposome plays an important role since genetic factors cannot explain such a rapid change. In the Human Exposomic Determinants of Immune Mediated Diseases (HEDIMED) project, altogether 22 academic and industrial partners join their multidisciplinary forces to identify exposomic determinants that are driving the IMD epidemic. The project is based on a combination of data and biological samples from large clinical cohorts constituting about 350,000 pregnant women, 30,000 children prospectively followed from birth, and 7,000 children from cross-sectional studies. HEDIMED focuses on common chronic IMDs that cause a significant disease burden, including type 1 diabetes, celiac disease, allergy, and asthma. Exposomic disease determinants and the underlying biological pathways will be identified by an exploratory approach using advanced omics and multiplex technologies combined with cutting-edge data mining technologies. Emphasis is put on fetal and childhood exposome since the IMD disease processes start early. Inclusion of several IMDs makes it possible to identify common exposomic determinants for the diseases, thus facilitating the development of widely operating preventive and curative treatments. HEDIMED includes data and samples from birth cohorts and clinical trials that have used exposomic interventions and cell and organ culture models to identify mechanisms of the observed associations. Importantly, HEDIMED generates a toolbox that offers science-based functional tools for key stakeholders to control the IMD epidemic. Altogether, HEDIMED aims at innovations, which become widely exploited in diagnostic, therapeutic, preventive, and health economic approaches.

Enterovirus Infections Are Associated With the Development of Celiac Disease in a Birth Cohort Study.

Enterovirus and adenovirus infections have been linked to the development of celiac disease. We evaluated this association in children who developed biopsy-proven celiac disease (N = 41) during prospective observation starting from birth, and in control children (N = 53) matched for the calendar time of birth, sex, and HLA-DQ genotype. Enterovirus and adenovirus infections were diagnosed by seroconversions in virus antibodies in longitudinally collected sera using EIA. Enterovirus infections were more frequent in case children before the appearance of celiac disease-associated tissue transglutaminase autoantibodies compared to the corresponding period in control children (OR 6.3, 95% CI 1.8-22.3; p = 0.005). No difference was observed in the frequency of adenovirus infections. The findings suggest that enterovirus infections may contribute to the process leading to celiac disease.

Early-life exposure to common virus infections did not differ between coeliac disease patients and controls.

AIM: Our aim was to compare the presence of various common viruses (rhinovirus, enterovirus, adenovirus, Epstein-Barr virus, cytomegalovirus, norovirus, parechovirus) in stool and nasal swab samples as well as virus-specific antibodies in serum samples between children who developed coeliac disease and controls. METHODS: A case-control study was established based on the DIABIMMUNE Study cohorts. During the study, eight Estonian children and 21 Finnish children aged 1.5 years to five years developed coeliac disease and each was matched with a disease-free control. Nasal swabs and stool samples were taken at the age of three to six months and the serum samples at the time of diagnosis. RESULTS: Rhinovirus ribonucleic acid was detected in the nasal swabs from five coeliac disease children, but none of the control children (p = 0.05). There were no statistically significant differences in the level of viral antibodies between cases and controls. Enterovirus immunoglobulin G class antibodies were found more frequently in the Estonian than in the Finnish children (63% versus 23%, p = 0.02). CONCLUSION: This study did not find any marked overall differences in laboratory-confirmed common viral infections between the children who developed coeliac disease and the controls. However, rhinovirus infections were detected slightly more often in those patients who developed coeliac disease.

Enterovirus infection during pregnancy is inversely associated with atopic disease in the offspring.

BACKGROUND: Prenatal environment has been shown to influence child's risk of atopic diseases. Laboratory-confirmed data about the role of maternal infections during pregnancy is scarce. OBJECTIVE: The aim of this study was to determine the associations between serologically confirmed maternal infections during pregnancy and atopic disease in the offspring. METHODS: This was a nested case-control study within a prospective birth cohort study. Altogether 202 atopic case children and 333 matched non-atopic control children were included. Atopic outcome was defined as having an atopic disease and IgE sensitization by the age of 5 years. We analysed serologically acute enterovirus (EV), influenza virus A (IAV) and Mycoplasma pneumoniae (M. pneumoniae) infections during pregnancy, and mother's seropositivity against human cytomegalovirus (CMV) and Helicobacter pylori. RESULTS: Maternal EV infection during pregnancy was inversely associated with atopic outcome in the offspring (odds ratio 0.43; 95% confidence interval: 0.23-0.80, P = 0.008). Acute IAV or M. pneumoniae infections or seropositivity against CMV or Helicobacter pylori were not associated with the atopic outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Our results suggest that maternal EV infections during pregnancy are inversely associated with atopic disease in the offspring. Our finding provides further support to the previous studies suggesting an important role of the in utero environment in the development of atopic diseases.

First trimester enterovirus IgM and beta cell autoantibodies in mothers to children affected by type 1 diabetes autoimmunity before 7 years of age.

BACKGROUND: Autoimmune (type 1) diabetes (T1D) is a frequent chronic disease in children and adolescents globally. Gestational enterovirus (EV) infections have been associated with an increased risk for T1D in the offspring. We test the hypothesis that EV infections during the first trimester were associated with beta cell autoantibodies in mothers of children who developed islet autoantibodies before 7 years of age. MATERIALS AND METHODS: Local registries were used to identify mothers to children born 2000-2007 who developed either beta cell autoantibodies or T1D during follow up. Serum samples from the first trimester were located in the Biobank. A total of 448 index mothers were identified and compared to 891 matched control mothers. EV-IgM was determined in a capture enzyme immunoassay. Beta cell autoantibodies were analyzed in standard radio binding assays. RESULTS: The frequency of EV-IgM in index mothers was 20% (89/448), which did not differ from the control mothers 20% (175/891) (p = 0.922). Index mothers had multiple beta cell autoantibodies more often than control mothers (p = 0.037). Beta cell autoantibodies were increased during the November-April winter months in index compared to control mothers (p = 0.022). The observed difference was possibly explained by the months of February-April (p = 0.014). Concomitant EV-IgM and beta cell autoantibodies tended to be more common among index compared to control mothers (p = 0.039). CONCLUSION: EV-IgM during the first trimester may be associated with beta cell autoantibodies in mothers to children who developed either beta cell autoantibodies or T1D before 7 years of age.

Genetic analyses of norovirus GII.4 variants in Finnish children from 1998 to 2013.

Noroviruses (NoVs) are the major causative agents of acute gastroenteritis (AGE) in outbreaks and in sporadic AGE in young children. Since the mid-1990s, NoV genotype GII.4 has been predominant worldwide. New GII.4 variants appear every two to three years, and antigenic variation is focused on the highly variable protruding domain (P2) of the NoV capsid protein which contains the receptor-binding regions. We studied NoV GII.4 variants in cases of endemic AGE in Finnish children from 1998 to 2013. Fecal specimens were collected from cases of AGE followed prospectively in rotavirus vaccine trials from 1998 to 2007, and from children seen at Tampere University Hospital because of AGE from 2006 to 2013. Partial capsid sequences were identified with RT-PCR and sequenced allowing P2 domain alignment and phylogenetic comparison of different GII.4 strains, with virus-like particles (VLPs) developed as candidate vaccines. Of 1495 NoV positive specimens 829 (55%) were of the GII.4 genotype, and altogether twelve GII.4 variants were identified. Identical GII.4 variants were detected in outbreaks of NoVs worldwide. A phylogenetic tree of the amino acid changes in the P2 region showed nine variants that arose over time. Our data indicates that GII.4 continues to be the predominant NoV genotype circulating in the Finnish community, and the changes in the P2 domain over time result in the development of new variants that cause AGE in children. Future NoV vaccines should either induce type specific immunity for each variant or, alternatively, induce broadly reactive protective immunity covering multiple variants.

Noroviruses as a major cause of acute gastroenteritis in children in Finland, 2009-2010.

Noroviruses are, after rotaviruses, the second most common cause of acute gastroenteritis in young children. In a prospective study conducted in 2009-2010 at the Tampere University Hospital, 195 stool specimens were collected from cases of acute gastroenteritis in children and examined for noroviruses, sapoviruses, and rotaviruses, using a reverse transcriptase polymerase chain reaction (RT-PCR). Noroviruses were found in 49 (25%) of the cases and sapoviruses in 12 (6%). The norovirus genotype GII.4 dominated with a 76% share; other genotypes detected were GII.7/GII.6 (16%), GII.g/GII.12, GII.e/GII.4, and GII.7 (2% each). For comparison, 47 (24%) cases of rotavirus gastroenteritis were diagnosed in the same period. In conclusion, after the introduction of rotavirus vaccination in Finland in September 2009, noroviruses have become as common as rotaviruses as the causative agents of acute gastroenteritis in young children, and are likely to become the leading cause. Norovirus GII.4 continues to be the dominant genotype.

Norovirus GII-4 causes a more severe gastroenteritis than other noroviruses in young children.

Norovirus (NoV) GII-4 has emerged as the predominant NoV genotype in outbreaks of gastroenteritis worldwide. We determined clinical features of NoV GII-4 associated acute gastroenteritis (AGE) in comparison with AGE associated with other NoV types in infants during seasons 2001 and 2002. During the prospective follow-up period, 128 primary infections of AGE due to NoV were identified in 405 infants; of these, GII-4 was found in 40 cases (31%). NoV GII-4 was associated with longer duration of diarrhea and vomiting than other NoV genotypes, suggesting greater virulence of NoV GII-4.

Efficacy of RIX4414 live attenuated human rotavirus vaccine in Finnish infants.

BACKGROUND: Rotavirus gastroenteritis, a major cause of mortality and morbidity worldwide, is a vaccine-preventable disease. New safe and effective candidate rotavirus vaccines are needed to replace the withdrawn rhesus rotavirus-based oral vaccine. METHODS: We evaluated a monovalent human rotavirus vaccine, serotype G1, strain RIX4414, for efficacy, immunogenicity and safety in a randomized, double blind, placebo-controlled trial in Finland. We randomly allocated 405 healthy infants to receive 2 doses of vaccine or placebo (ratio 2:1) at approximately 2 and 4 months of age. The infants were followed during 2 rotavirus epidemic seasons (2000-2002) for acute gastroenteritis. Rotaviruses in diarrheal stool samples were primarily detected by enzyme-linked immunosorbent assay and confirmed and G-typed by reverse transciption-polymerase chain reaction. RESULTS: The vaccine was well-tolerated. No vaccine-related serious adverse events were observed during the study period. Rotavirus IgA (enzyme-linked immunosorbent assay) seroconversion rate was 80% after 2 doses. Thirty-eight cases of rotavirus gastroenteritis were detected during the entire follow-up period; 35 of these were of the G1 type. RIX4414 vaccine significantly decreased the occurrence of any rotavirus compared with placebo. Efficacy during the first rotavirus epidemic season was 73% [95% confidence interval (95% CI), 27-91%] and 90% (95% CI 10-100%) against any and severe rotavirus gastroenteritis, respectively, and during the entire follow-up period 72% (95% CI 42-87%) against any and 85% (95% CI 42-97%) against severe rotavirus gastroenteritis (P < 0.05 for all comparisons). CONCLUSIONS: RIX4414 strain of G1 human rotavirus vaccine was well-tolerated, immunogenic and efficacious in infants against rotavirus gastroenteritis during a 2-year period. To further increase vaccine "take" and efficacy, a higher dose of this vaccine may be considered for future efficacy trials.