Tero Saukkonen

Coeliac disease : Frequent occurrence after clinical onset of insulin-dependent diabetes mellitus

Coeliac disease was searched for in a series of 776 children with newly diagnosed IDDM. During the follow‐up of 2 to 3 years from diagnosis, reticulin and gliadin antibodies were measured, and a jejunal biopsy was performed in those cases with high levels of antibodies; 19 children were identified with coeliac disease, giving the prevalence of 2.4 %. In only one case had coeliac disease been diagnosed before IDDM. Nine patients with proven coeliac disease were negative for antibodies when IDDM was diagnosed, but became positive within 24 months. All patients found to have coeliac disease were positive for IgA reticulin antibodies, but only 12 of 18 (67 %) showed a high level of IgA gliadin antibodies. Of the 18 patients genotyped for HLA DR locus, 14 (78 %) were positive for DR3 and 10 (56 %) were positive for DR4. DQB1*0201 allele was present in 17 of 18 patients (94 %). Coeliac disease in children with IDDM tends to develop soon after diabetes is diagnosed. Routine screening for coeliac disease is recommended repeatedly during the first years after the diagnosis of IDDM.

Development of immune response to cow's milk proteins in infants receiving cow's milk or hydrolyzed formula

BACKGROUND Development of humoral and cellular immune responses to orally administered antigens in human beings is poorly understood, although antigen administration has been suggested as a treatment for hypersensitivity disorders and autoimmune diseases. OBJECTIVE The purpose of the study was to investigate the development of systemic immune response in infants fed with formula containing whole cows milk proteins or hydrolyzed formula containing casein peptides. METHODS In a double-blind trial, 10 infants received cows milk-based formula, and 10 infants received a casein hydrolysate formula until the age of 9 months. Blood samples were taken at the ages of 6, 9, and 12 months. Cellular responses were assessed by proliferation assay of peripheral blood mononuclear cells to cows milk proteins (beta-lactoglobulin, bovine serum albumin, and alpha-casein). Humoral responses to the same proteins were measured by ELISA for IgG antibodies. RESULTS Feeding infants with cows milk-based formula induced systemic humoral and cellular responses to cows milk proteins. T-cell response later declined, supporting the concept of oral tolerization. Exposure to cows milk proteins after the age of 9 months resulted in depressed cellular and humoral responsiveness to these proteins. CONCLUSION Our results support the view that induction of oral tolerance in human beings is an age-dependent phenomenon.

Increased Levels of Cow's Milk and β-Lactoglobulin Antibodies in Young Children With Newly Diagnosed IDDM

Objective— To investigate the humoral immune response to cows milk in pediatric patients with newly diagnosed IDDM. Research Design and Methods— We measured IgA, IgG, and IgM antibodies to the proteins of cows milk and to β-lactoglobulin by an enzyme-linked immunosorbent assay. Samples from 706 pediatric patients with newly diagnosed IDDM were available. We used two comparison groups: 105 patients < 7 yr old had an unrelated age-matched control subject, and samples from 456 3- to 14-yr-old nondiabetic siblings also were available. Results— Patients < 3 yr of age had a markedly higher median level of IgG and IgA antibodies to cows milk compared with the control subjects (P = 0.03 and 0.002, respectively), IgG antibodies to β-lactoglobulin also were higher (P = 0.03). Older groups of diabetic patients, 3.0–6.9 and 7.0–14.9 yr of age, had significantly higher levels of IgA antibodies to cows milk and β-lactoglobulin than the age-matched comparison groups of both unrelated control subjects and nondiabetic siblings, although the median values of the diabetic patients were closer to those of the comparison groups than in the youngest groups. Nondiabetic siblings had higher levels of IgA cows milk antibodies than unrelated control subjects of similar ages (3–6.9 yr of age) (P = 0.03). The 14 siblings contracting IDDM during the follow-up showed no change in the levels of cows milk or β-lactoglobulin antibodies in relation to the clinical diagnosis. Conclusions— The results indicate an abnormally strong humoral response to the proteins of cows milk, particularly in young IDDM patients and, to a lesser extent, in their siblings. We infer that the proteins of cows milk may trigger the autoimmune process of IDDM.

Intestinal permeability to mannitol and lactulose in children with type 1 diabetes with the HLA-DQB1*02 allele.

Food antigens and enteroviruses are possible triggers of type 1 diabetes. Because permeability of the intestinal epithelium may facilitate contact of these antigens with the mucosal immune system, we set out to study intestinal permeability in patients with type 1 diabetes. Children with type 1 diabetes (n = 26, mean age 12 years, mean duration of disease 4 years) and 24 healthy age-matched control children were given mannitol and lactulose orally, and their intestinal permeability was measured as a percentage of this dose recovered in urine. Patients with type 1 diabetes did not differ in their permeability to lactulose, nor was their lactulose/mannitol ratio any different from that of controls. However, patients with type 1 diabetes who had the HLA-DQB1 H 02 allele and, therefore, a higher risk for celiac disease (CD) absorbed significantly more mannitol (mean+95% CI): 17.7% (15.2-20.2) than did those negative for this allele: 12.3% (8.2-16.4), p = 0.04. Their lactulose permeability was also higher: 0.30 (0.16-0.44) and 0.09% (0-0.18), respectively, p = 0.02. Although the differences in permeability reach statistical significance, there was still much overlap between the two groups in terms of actual laboratory values. The higher permeability of patients with the HLA-DQB1 H 02 allele suggests that these patients may be more prone to develop abnormal immune responses to food antigens.

Diet, cow's milk protein antibodies and the risk of IDDM in Finnish children

SummaryAssociations of infant feeding patterns and milk consumption with cows milk protein antibody titres were studied in 697 newly-diagnosed diabetic children, 415 sibling-control children and 86 birth-date-and sex-matched population-based control children in the nationwide “Childhood Diabetes in Finland” study. IgA and IgG antibody titres to the proteins of cows milk formula, BLG and BSA, and IgM antibody titres to cows milk formula proteins were measured by ELISA. Several inverse correlations were observed between the duration of breast-feeding or age at introduction of dairy products and antibody titres, and positive correlations were observed between milk consumption and antibody titres in all three populations studied. Multivariate analyses which included the infant feeding variables, milk consumption and current age simultaneously showed that the earlier the introduction of dairy products and the greater the consumption of milk was, the higher several antibody titres were. High IgA antibody titres to cows milk formula were associated with a greater risk of IDDM both among diabeticpopulation-control and diabetic-sibling-control pairs when adjusted for other cows milk antibody titres, dietary variables and in diabetic-sibling-control pairs also for ICA. The results suggest that young age at introduction of dairy products and high milk consumption during childhood increase the levels of cows milk antibodies and that high IgA antibodies to cows milk formula are independently associated with increased risk of IDDM.

Low density lipoprotein receptor‐related protein 5 (LRP5) mutations and osteoporosis, impaired glucose metabolism and hypercholesterolaemia

Objective  Mutations in the low‐density lipoprotein receptor‐related protein 5 gene (LRP5) underlie osteoporosis–pseudoglioma syndrome. Animal models implicate a role for LRP5 in lipid and glucose homeostasis. The objective was to evaluate metabolic consequences of LRP5 mutations in humans.

Children with newly diagnosed IDDM have increased levels of antibodies to bovine serum albumin but not to ovalbumin

OBJECTIVE To study the humoral immune response to bovine serum albumin (BSA) and ovalbumin (OA) in children with newly diagnosed insulin-dependent diabetes mellitus (IDDM). RESEARCH DESIGN AND METHODS We examined serum samples from 505 children 0.8–14.9 years of age with newly diagnosed IDDM for antibodies to BSA and OA by enzyme-linked immunosorbent assay (ELISA). We also had two control groups: 85 unrelated control children (0.8–7.1 years of age) and 395 nondiabetic siblings (3.0–14.9 years of age). The specificity of antibodies detected in ELISA was confirmed by immunoblotting in a subset of sera with varying levels of antibodies. RESULTS Diabetic children <7 years of age had a significantly higher level of IgG (immunoglobulin) antibodies to BSA than did unrelated control children (P < 0.0001). The difference was greatest in the youngest group of children, 0.8–2.9 years of age. IgA antibodies to BSA were detected more frequently among diabetic than control children (P = 0.0009). Levels of IgG and IgA antibodies to ovalbumin did not differ between diabetic and control children. Diabetic children 3.0–14.9 years of age also had higher levels of IgG and IgA antibodies to BSA than did their age- and sex-matched nondiabetic siblings (P = 0.02 and P < 0.0001, respectively). Those siblings who contracted IDDM during the follow-up period (n = 15) had a measurable level of IgA antibodies to BSA more often than did those who remained nondiabetic (60 and 34%, respectively; P = 0.04). Neither before nor after diagnosis of IDDM was there any significant trend in antibody levels. CONCLUSIONS A high level of antibodies to BSA commonly associates with IDDM, whereas the humoral immune response to OA is similar in diabetic and nondiabetic children.

Coeliac disease in children and adolescents with type 1 diabetes: a study of growth, glycaemic control, and experiences of families

The aim of this study was to evaluate whether coeliac disease affects growth, glycaemic control, and general well‐being of children and adolescents with type 1 diabetes. Eighteen subjects were found to have coeliac disease by a screening program. Gastrointestinal symptoms, changes in growth and the levels of glycated haemoglobin (GHbA1) were analysed, as well as subjective well‐being before and after diagnosis of coeliac disease. Overt gastrointestinal symptoms and deterioration of growth prior to disclosure of coeliac disease were seen only in one patient who had both of these conditions. Retrospectively, most subjects reported mild gastrointestinal complaints, which resolved on a gluten‐free diet. Introduction of a gluten‐free diet did not have any positive effect on glycaemic control, but was associated with an increase in weight‐for‐height (from 4.3 ± 18.1 to 8.2 ± 15.4% deviation from population median, p= 0.02). This increase in weight‐for‐height was inversely correlated with changes in GHbA1 (r=– 0.574, p= 0.02).

Disease-Associated Antibodies in Offspring of Mothers with IDDM

We studied 20 infants of mothers with IDDM participating in a pilot study for a dietary intervention trial, testing the hypothesis that avoidance of cows milk proteins early in life will reduce the risk of subsequent IDDM. The aim was to evaluate the elimination of IDDM-associated antibodies from the peripheral circulation of the infants, the possible emergence of autoantibodies indicating β-cell destruction, and the influence of the dietary intervention and genetic disease susceptibility on the development of these autoantibodies. Transplacentally transferred islet cell antibodies (ICAs) and antibodies to the 65-kDa isoform of glutamic acid decarboxylase (GAD65As) disappeared from the peripheral circulation of most infants over the first few months of life and in all infants before the age of 9 months. Insulin antibodies were eliminated before the same age in all cases but one. The higher the initial antibody level was, the longer the time required for elimination. Four infants tested positive for insulin autoantibodies (IAAs) on at least one occasion during the first year of life, and 5 out of 16 unaffected subjects (31%) had IAAs at the age of 2 years. One infant became positive for IAA before the age of 6 months, with increasing levels later, seroconverted to positivity for ICAs and GAD65As between 6 and 9 months and presented with clinical IDDM at the age of 14 months. He had the HLA DQB1*0302/x genotype, which predisposes carriers to IDDM, and had been given the casein hydrolysate formula as supplementary milk. There were no significant differences in the levels of various autoantibodies between two groups of subjects defined either on the type of dietary intervention or the degree of genetic susceptibility. The findings indicate that transplacentally transferred antibodies related to IDDM are usually eliminated from the peripheral circulation of infants before 9 months of age and that IDDM-associated autoantibodies may emerge before the age of 6 months. Our results also illustrate that avoidance of cows milk proteins over the first 9 months of life does not provide total protection against IDDM.

Disease-associated anti-bovine serum albumin antibodies in Type 1 (insulin-dependent) diabetes mellitus are detected by particle concentration fluoroimmunoassay, and not by enzyme linked immunoassay

SummaryWe recently developed a particle concentration fluoroimmunoassay for the measurement of serum antibodies to bovine serum albumin in patients with Type 1 (insulin-dependent) diabetes mellitus. We observed elevated IgG-anti-bovine serum albumin antibodies in 100% of newly-diagnosed diabetic children and in 2.5% of matched control children. Here we compare the fluoroimmunoassay and the more commonly available enzyme linked immunoassay technique, exchanging coded serum samples from 40 newly-diagnosed diabetic children and 179 control children between two laboratories. Particle concentration fluoroimmunoassay detected elevated IgG-anti-bovine serum albumin antibodies in all diabetic children, enzyme immunoassay in 25% (p <0.0001). Fluoroimmunoassay detected elevated levels in 2.2% and enzyme immunoassay in 10% of control children (p <0.002). Elevated IgA-antibovine serum albumin antibodies in patients were slightly more often detected by fluoroimmunoassay than by enzyme immunoassay, while in control children enzyme immunoassays detected elevated levels three times more often (p <0.01). Values measured in either assay showed overall no correlation in either patient (IgG: rs = 0.28; IgA: rs = 0.11) or control sera (IgG: rs = 0.02; IgA: rs = -0.05). Fluoroimmunoassay for IgG was 100% disease-sensitive (enzyme immu-noassay: 25%, p <0.0001) and more disease-specific (IgG; p <0.02). Our findings demonstrate that these assay techniques detected distinct subsets of anti-bovine serum albumin antibodies with little (IgG) or some (IgA) overlap. In fluoroimmunoassay procedures, antigen: antibody binding occurs within 1–2 min while hours are allowed in an enzyme immunoassay. Antibodies with high on-off binding rates typical for immune responses following hyperimmunization are therefore measured preferentially by particle concentration fluoroimmunoassay and it is these antibodies which appear to be associated with diabetes. These observations emphasize the need for epidemiological surveys to validate immunoassay procedures used for clinical purposes.