HLA-DQB1/DRB1 Alleles Associate with Traditional Chinese Medicine Syndrome of Chronic Hepatitis B: A Potential Predictor of Progression.

BACKGROUND AND AIMS: Traditional Chinese medicine (TCM) has been widely applied in chronic hepatitis B (CHB) supplementary treatment in China. Kidney yang deficiency syndrome (KYDS), one of the most common TCM syndromes of CHB, is more likely to progress to liver cirrhosis or hepatocellular carcinoma than other syndromes. Polymorphisms in the human leucocyte antigen- (HLA-) DQB1 and -DRB1 genes were reported to be associated with hepatitis B virus infection outcomes. Here, we investigated whether HLA-DQB1 and HLA-DRB1 are associated with the classification of CHB TCM syndromes. METHODS: We genotyped HLA-DQB1 and HLA-DRB1 alleles in a total of 105 subjects, including 74 CHB patients (28 KYDS and 46 non-KYDS) and 31 healthy individuals from Sichuan Province of Southwest China, by polymerase chain reaction sequence-based typing (PCR-SBT). Moreover, a meta-analysis was carried out for further verification. RESULTS: The proportion of patients with high HBV DNA load (≥2000 IU/ml) in the KYDS group is higher than that in the non-KYDS group (60.70% [17/28] vs. 28.30% [13/46]); P=0.01). The frequencies of HLA-DQB1∗02:01 (P=0.04) and HLA-DRB1∗03:01 (P=0.04) in the KYDS group were significantly increased compared to the non-KYDS group. The gene test and meta-analysis showed that HLA-DRB1∗08:03 confers susceptibility to CHB (odds ratio = 1.57). CONCLUSION: We found an association between HLA-DRB1/DQB1 polymorphisms and KYDS of CHB. Moreover, KYDS patients of CHB are characteristic with high HBV DNA loads. These findings help to reveal the biological mechanism of KYDS in high risk of CHB progression and suggest a potential prognostic value for disease outcome evaluation.

Autoantibodies in Pandemrix®-induced narcolepsy: Nine candidate autoantigens fail the conformational autoantibody test.

Study objectives: Narcolepsy type 1 (NT1) is a chronic sleep disorder characterized by loss of hypocretin-producing neurons. Increased NT1 incidence was observed in Sweden following mass-vaccination with Pandemrix®. Genetic association to HLA DQB1*06:02 implies an autoimmune origin, but target autoantigen remains unknown. Candidate autoantigens for NT1 have previously been identified in solid-phase immunoassays, while autoantibodies against conformation-dependent epitopes are better detected in radiobinding assays. The aims are to determine autoantibody levels against nine candidate autoantigens representing (1) proteins of the hypocretin transmitter system; Preprohypocretin (ppHypocretin), Hypocretin peptides 1 and 2 (HCRT1 and HCRT2) and Hypocretin receptor 2 (HCRTR2); (2) proteins previously associated with NT1; Tribbles homologue 2 (TRIB2), Pro-opiomelanocortin/alpha-melanocyte-stimulating-hormone (POMC/α-MSH) and Prostaglandin D2 Receptor DP1 (DP1); (3) proteins suggested as autoantigens for multiple sclerosis (another HLA DQB1*06:02-associated neurological disease); ATP-dependent Inwardly Rectifying Potassium Channel Kir4.1 (KIR4.1) and Calcium-activated chloride channel Anoctamin 2 (ANO2). Methods: Serum from post-Pandemrix® NT1 patients (n = 31) and their healthy first-degree relatives (n = 66) were tested for autoantibody levels in radiobinding assays separating autoantibody bound from free labelled antigen with Protein A-Sepharose. 125I-labelled HCRT1 and HCRT2 were commercially available while 35S-methionine-labelled ppHypocretin, HCRTR2, TRIB2, α-MSH/POMC, DP1, KIR4.1 or ANO2 was prepared by in vitro transcription translation of respective cDNA. In-house standards were used to express data in arbitrary Units/ml (U/ml). Results: All radiolabelled autoantigens were detected in a concentration-dependent manner by respective standard sera. Levels of autoantibodies in the NT1 patients did not differ from healthy first-degree relatives in any of the nine candidate autoantigens. Conclusions: None of the nine labelled proteins proposed to be autoantigens were detected in the radiobinding assays for conformation-dependent autoantibodies. The results emphasise the need of further studies to identify autoantigen(s) and clarify the mechanisms in Pandemrix®-induced NT1.

Widespread white matter changes in post-H1N1 patients with narcolepsy type 1 and first-degree relatives.

Study Objectives: To assess white matter involvement in H1N1-vaccinated hypocretin deficient patients with narcolepsy type 1 (NT1) compared with first-degree relatives (a potential risk group) and healthy controls. Methods: We compared four diffusion tensor imaging-based microstructural indices (fractional anisotropy [FA], mean diffusivity [MD], radial diffusivity [RD], and axial diffusivity [AD]) in 57 patients with NT1 (39 females, mean age 21.8 years, 51/57 H1N1-vaccinated, 57/57 HLA-DQB1*06:02-positive, 54/54 hypocretin-deficient), 54 first-degree relatives (29 females, mean age 19.1 years, 37/54 H1N1-vaccinated, 32/54 HLA-DQB1*06:02-positive), and 55 healthy controls (38 females, mean age 22.3 years). We tested for differences between these groups, for parametric effects (controls > first-degree relatives > patients) and associations in patients (cerebrospinal fluid [CSF] hypocretin-1 and disease duration) and first-degree relatives (HLA-DQB1*06:02 and H1N1-vaccination). We employed tract-based spatial statistics and used permutation testing and threshold-free cluster enhancement for inference. Results: Patients with NT1 had a widespread, bilateral pattern of significantly lower FA compared with first-degree relatives and healthy controls. Additionally, patients with NT1 also exhibited significantly higher RD and lower AD in several focal white matter clusters. The parametric model showed that first-degree relatives had intermediate values. Full sample of patients with NT1 showed no significant associations with disease duration or CSF hypocretin-1. Conclusions: Our study suggests widespread abnormal white matter involvement far beyond the already known focal hypothalamic pathology in NT1, possibly reflecting the combined effects of the loss of the widely projecting hypothalamic hypocretin neurons, and/or secondary effects of wake/sleep dysregulation. These findings demonstrate the importance of white matter pathology in NT1.

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.

Antigenic peptide molecular recognition by the DRB1-DQB1 haplotype modulates multiple sclerosis susceptibility.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that has a notably high incidence in Sardinia. Our study focuses on two HLA class II haplotypes associated with the disease in Sardinia, the rare predisposing DRB1*15:01-DQB1*06:02 and the widespread protective DRB1*16:01-DQB1*05:02. This framework enabled the highlighting of HLA binding pocket specificity and peptide recognition mechanisms by employing molecular dynamics simulations of the whole DRB1-DQB1 haplotype interacting with MBP- and EBV-derived peptides. We analyzed peptide-protein interaction networks and temporal evolution of the original complexes and after key amino acid mutations. The mutation G86V of the protective DRB1 allele exerted its effect mainly in the presence of the EBV viral peptide, with local and long range outcomes. However, the V38A mutation of the protective DQB1 showed a long range effect only in the case of the MBP myelin peptide. Our findings also demonstrate a DRB1/DQB1 complementary molecular recognition of peptides. This mechanism could provide a robust synergistic action and a differential role of DRB1 and DQB1 in tissues and in the time-steps towards autoimmunity. In addition, we demonstrate that negatively charged residues in pockets 4 and 9 play a role in MS susceptibility. Our findings are supported by recent experiments using a closely related MS animal model. Overall, our analysis confirms the role of the DRB1-DQB1 haplotype in conferring disease predisposition and could provide a valuable aid in designing optimal therapeutic peptides for MS therapy.

The adjuvant component α-tocopherol triggers via modulation of Nrf2 the expression and turnover of hypocretin in vitro and its implication to the development of narcolepsy.

BACKGROUND: After the H1N1 swine flu vaccination campaign an increased number of narcolepsy cases in children and adolescents was observed in Scandinavian and later in further European countries that correlated with the vaccination by an AS03-adjuvanted influenza vaccine (Pandemrix). Narcolepsy is a chronic sleep disorder characterized by the loss of hypocretin in the cerebrospinal fluid due to selective destruction of hypocretin-producing neurons in the perifornical hypothalamus. In >99% of the cases narcolepsy is associated with the HLA-subtype DQB1*602 giving the link to an autoimmune process. In contrast to other squalene-based adjuvants, for which no association with narcolepsy was reported so far, ASO3 contains in addition α-tocopherol. It could be observed recently that α-tocopherol activates the transcription factor Nrf2. Nrf2 triggers the expression of cytoprotective genes, i.e. the catalytic active subunits of the constitutive proteasome, by binding to the antioxidant response element (ARE). It was hypothesized that α-tocopherol via activation of Nrf2 affects expression and turnover of hypocretin, leading to an increased amount of hypocretinα-specific fragments that bind to DQB1*602. RESULTS: α-Tocopherol activates Nrf2 in neuronal cells in vitro. Promoter analysis revealed an ARE sequence in the hypocretin promoter. Indeed, α-tocopherol increases by activation of Nrf2 the expression of hypocretin. In parallel, α-tocopherol -dependent induction of Nrf2 augments expression of catalytic subunits of the proteasome leading to increased degradation of hypocretin. Moreover, elevated activation of Nrf2 is associated with a decreased activity of NF-κB that results in an increased sensitivity to apoptotic stimuli. CONCLUSION: In case of a genetic predisposition (DQB1*602) α-tocopherol could confer to development of narcolepsy by activation of Nrf2 that finally leads to an elevated formation of longer hypocretin-derived fragments that can be presented by HLA-subtype DQB1*602. These cells are recognized by the immune system and due to their increased sensitivity to apoptotic stimuli they can be destroyed, finally leading to a lack of hypocretin.

Eukaryotic translation initiation factor 5A inhibition alters physiopathology and immune responses in a "humanized" transgenic mouse model of type 1 diabetes.

Therapeutic options for treatment of type 1 diabetes (T1D) are still missing. New avenues for immune modulation need to be developed. Here we attempted at altering the diabetes outcome of our humanized model of T1D by inhibiting translation-initiation factor eIF5A hypusination in vivo. Double-transgenic (DQ8-GAD65) mice were immunized with adenoviral vectors carrying GAD65 for diabetes induction. Animals were subsequently treated with deoxyhypusine synthase (DHS) inhibitor GC7 and monitored for diabetes development over time. On one hand, helper CD4(+) T cells were clearly affected by the downregulation of the eIF5A not just at the pancreas level but overall. On the other hand, the T regulatory cell component of CD4 responded with activation and proliferation significantly higher than in the non-GC7-treated controls. Female mice seemed to be more susceptible to these effects. All together, our results show for the first time that downregulation of eIF5A through inhibition of DHS altered the physiopathology and observed immune outcome of diabetes in an animal model that closely resembles human T1D. Although the development of diabetes could not be abrogated by DHS inhibition, the immunomodulatory capacity of this approach may supplement other interventions directed at increasing regulation of autoreactive T cells in T1D.

A/H1N1 antibodies and TRIB2 autoantibodies in narcolepsy patients diagnosed in conjunction with the Pandemrix vaccination campaign in Sweden 2009-2010.

Narcolepsy is a lifelong sleep disorder related to hypocretin deficiency resulting from a specific loss of hypocretin-producing neurons in the lateral hypothalamic area. The disease is thought to be autoimmune due to a strong association with HLA-DQB1*06:02. In 2009 the World Health Organization (WHO) declared the H1N1 2009 flu pandemic (A/H1N1PDM09). In response to this, the Swedish vaccination campaign began in October of the same year, using the influenza vaccine Pandemrix(®). A few months later an excess of narcolepsy cases was observed. It is still unclear to what extent the vaccination campaign affected humoral autoimmunity associated with narcolepsy. We studied 47 patients with narcolepsy (6-69 years of age) and 80 healthy controls (3-61 years of age) selected after the Pandemrix vaccination campaign. The first aim was to determine antibodies against A/H1N1 and autoantibodies to Tribbles homolog 2 (TRIB2), a narcolepsy autoantigen candidate as well as to GAD65 and IA-2 as disease specificity controls. The second aim was to test if levels and frequencies of these antibodies and autoantibodies were associated with HLA-DQB1*06:02. In vitro transcribed and translated [(35)S]-methionine and -cysteine-labeled influenza A virus (A/California/04/2009/(H1N1)) segment 4 hemagglutinin was used to detect antibodies in a radiobinding assay. Autoantibodies to TRIB2, GAD65 and IA-2 were similarly detected in standard radiobinding assays. The narcolepsy patients had higher median levels of A/H1N1 antibodies than the controls (p = 0.006). A/H1N1 antibody levels were higher among the <13 years old (n = 12) compared to patients who were older than 30 years (n = 12, p = 0.014). Being HLA-DQB1*06:02 positive was associated with higher A/H1N1 antibody levels in both patients and controls (p = 0.026). Serum autoantibody levels to TRIB2 were low overall and high binders did not differ between patients and controls. We observed an association between levels of A/H1N1 antibodies and TRIB2 autoantibody levels particularly among the youngest narcolepsy patients (r = 0.819, p < 0.001). In conclusion, following the 2009 influenza pandemic vaccination, A/H1N1 antibody levels were associated with young age-at-onset narcolepsy patients positive for HLA-DQB1*06:02. The possibility that TRIB2 is an autoantigen in narcolepsy remains to be clarified. We could verify autoantibody responses against TRIB2 which needs to be determined in larger patient cohorts and control populations.

[The Kleine-Levin syndrome: new aspects of a rare disease]. / Das Kleine-Levin-Syndrom : Neues von einer seltenen Erkrankung.

The Kleine-Levin syndrome (KLS) is a rare disease which can occur one to several times per year. The KLS belongs to the group of hypersomnia of central origin occurring mainly during the second decade of life after infections, sleep deprivation, alcohol consumption or minor trauma. Early manifestation combined with hypersexuality during symptomatic phases can be a predictor for a long course of the disease, which lasts a mean of 1-27 years. Due to the lack of biological markers diagnosis at first manifestation is difficult. The classical trias of hypersomnia, hyperphagia and hypersexuality can only be found in 45 % of patients. The dominant clinical symptoms are hypersomnia with changes in perception and behavior. Subtraction of perfusion studies performed during symptomatic and asymptomatic phases showed decreased perfusion of the left hypothalamus, thalamus, basal ganglia, medial and dorsolateral frontal and temporal regions. In the few patients who had lumbar punctures in both symptomatic and asymptomatic phases hypocretin-1 was moderately to slightly lowered during symptomatic phases. Meta-analyses showed good therapeutic effects of stimulants on the symptom sleepiness. Lithium reduces the frequency and duration of symptomatic phases. Assuming that KLS is underdiagnosed it should be considered as a differential diagnosis in young patients with recurrent hypersomnia.

[Diagnostic and therapeutic update in narcolepsy]. / Actualizacion diagnostica y terapeutica en narcolepsia.

Narcolepsy is an emblematic, unique disease within sleep disorders that is characterised by excessive daytime sleepiness, cataplexy and other abnormal manifestations of REM sleep. In the last 14 years truly spectacular progress has been made in our knowledge of this disease, since the discovery of its cause, i.e. a loss of the hypothalamic neurons that synthesise hypocretin, a previously unknown neurotransmitter, and its probable aetiopathogenic mechanisms, i.e. an autoimmune process in a patient with very precise immunological characteristics - a specific type of HLA and a specific type of T-cell receptor. The cause of this autoimmune process remains unknown. The definitive treatment - the administration of hypocretin, which is the substance missing in the organism - is still unavailable, but there are powerful drugs for treating its main symptoms, the sleepiness and the cataplexy. Some of these are classic compounds (methylphenidate, clomipramine), while others are more recent (modafinil, venlafaxine, sodium oxybate), but together they allow many patients to experience significant improvements. Lack of knowledge about the disease, both on the part of patients and their relatives as well as physicians, is the reason for the great delay in its diagnosis, with even more dramatic consequences when the disease begins in infancy.

Sleepiness that cannot be overcome: narcolepsy and cataplexy.

Narcolepsy-cataplexy syndrome is characterized by excessive daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep. It is strongly associated with the genetic marker, human leucocyte antigen (HLA) DQB1*06:02. A deficit in the endogenous hypocretin/orexin system due to neuronal degeneration in the lateral hypothalamus, induced by an autoimmune-mediated process, is the primary pathophysiology associated with the human disease. The important finding of an association with hypocretin genes in animal models of narcolepsy has led to the establishment of cerebrospinal fluid hypocretin measurements as a new diagnostic test for human narcolepsy. This is a fascinating story of translation of basic science research into clinical practice in sleep medicine during the past decade. Recent advances have shed light on the associations between respiratory medicine and narcolepsy-cataplexy research. The first is that upper airway infections, including H1N1 and/or streptococcal infections, may initiate or reactivate an immune response that leads to loss of hypocretin-secreting cells and narcolepsy in genetically susceptible individuals. The second is that an increased incidence of sleep disordered breathing among narcoleptic subjects may relate to the impairment of central control of breathing, linked to hypocretin deficiency or carriage of HLADQB1*06:02, in animals and human subjects with narcolepsy, respectively, indicating neural dysfunction in an area where respiratory and sleep-wake systems are closely interrelated.

Narcolepsy in the pediatric population.

Narcolepsy is characterized by excessive daytime sleepiness, with or without cataplexy. Associated features include sleep paralysis, hypnagogic or hypnopompic hallucinations, and disturbed nocturnal sleep. Narcolepsy is strongly associated with the HLA DQB1*0602 allele, and its symptoms stem from destruction of hypocretin-secreting neurons in the hypothalamus. Recently identified autoantibodies to Tribbles homologue 2 in some patients, as well as cases associated with H1N1 vaccination, support an autoimmune mechanism. There are many challenges in diagnosing and treating pediatric narcolepsy. Caution must also be used in interpreting polysomnography and multiple sleep latency test results in children. HLA testing is nonspecific, and no commercial test exists to measure cerebrospinal fluid hypocretin levels. Neuroimaging has not yet proven useful in primary narcolepsy. Treatment of sleepiness and cataplexy in children requires extrapolating from adult studies. Hopefully, further insights into the pathophysiology of narcolepsy will allow for new therapeutics to manage the symptoms and modify the course of the disease.

Characterization of 236 novel alleles at the HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 loci from China Marrow Donor Program.

Two hundred and thirty-six novel human leukocyte antigen (HLA) alleles are described from volunteer donors of the China Marrow Donor Program: 71 HLA-A alleles, 79 HLA-B alleles, 43 HLA-C, 16 HLA-DRB1 alleles, 26 HLA-DQB1 and 1 HLA-DPB1. Two hundred and thirteen (90.3%) of the 236 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Seventy-eight of these single nucleotide variants are silent substitutions. The remaining novel alleles differ from their most similar allele by two to four nucleotide substitutions. Some of the novel alleles encode amino acid changes at positions not previously reported to be polymorphic, such as codons 57, 62, 67, 41 and 52 in HLA-A alleles; codons 133, 156, 201 and 215 in HLA-B alleles; codons 74, 208 and 225 in HLA-C; codons 25, 32 and 72 in HLA-DRB1; codons 20, 39 and 77 in HLA-DQB1.

Serum fatty acids and risk of advanced beta-cell autoimmunity: a nested case-control study among children with HLA-conferred susceptibility to type I diabetes.

BACKGROUND/OBJECTIVES: N-3 (omega-3) fatty acids have been reported to decrease the risk for development of beta-cell autoimmunity and clinical type I diabetes. We set out to examine whether different serum fatty acids are associated with the development of advanced beta-cell autoimmunity in children carrying human leukocyte antigen DQ beta-1 (HLA-DQB1)-conferred susceptibility to type I diabetes. SUBJECTS/METHODS: Within a cohort, serum total fatty acid composition of 108 children with advanced beta-cell autoimmunity and of 216 matched persistently autoantibody-negative controls was analyzed using gas chromatography. Non-fasting serum samples were obtained annually at the ages of 1-6 years. Conditional logistic regression was applied to analyze the associations between advanced beta-cell autoimmunity and serum fatty acids. RESULTS: The serum fatty acid profile of myristic acid (odds ratio (OR) 1.48, 95% confidence interval (CI) 1.09-2.00, P=0.011), pentadecanoic acid (OR 1.65, 95% CI 1.19-2.28, P=0.003), palmitoleic acid isomers 16:1 n-7 (omega-7) (OR 1.41, 95% CI 1.03-1.92, P=0.030) and 16:1 n-9 (omega-9) (OR 1.45, 95% CI 1.05-2.01, P=0.026) and conjugated linoleic acid (OR 1.67, 95% CI 1.16-2.41, P=0.006) closest to the time of the appearance of multiple autoantibodies were positively associated with the risk of advanced beta-cell autoimmunity after adjustment for potential confounding factors. Serum linoleic acid showed inverse, marginal association with the end point. CONCLUSIONS: Serum biomarkers of milk and ruminant meat fat consumption are directly associated and linoleic acid is inversely associated with advanced beta-cell autoimmunity in children with HLA-conferred susceptibility to type I diabetes.

HLA genes in populations of the Aleutian islands.

We typed a subset of the Aleut population for HLA loci (HLA-A, HLA-B, HLA-DRB1, HLA-DQB1) to obtain an HLA profile, which was compared to other Eurasian and Amerindian populations for studying Aleut origin and its significance on the peopling of the Americas. Allele frequencies at the four loci were identified in an Aleut sample using standard indirect DNA sequencing methods. Genetic distances with Amerindians and Eurasians were obtained by comparing Aleut allele frequencies with a worldwide population database (13,164 chromosomes). The most frequently extended HLA haplotypes were also calculated. We also generated Aleut relatedness dendrograms and calculated correspondence relatedness in a multidimensional scale. Both neighbor-joining dendrograms and correspondence analysis separated Aleuts from Eskimos and Amerindians. Aleuts are closer genetically to Europeans, including Scandinavians and English. Our results are concordant with those obtained by Y-chromosome analysis, suggesting that most male Aleut ancestors of our sample came mainly from Europe.

Human leukocyte antigen (DR1)-DQB1*0501 and (DR15)-DQB1*0602 haplotypes are associated with humoral responses to early food allergens in children.

BACKGROUND: Infants' immunological responses to cow's milk (CM) proteins, which in 2-3% result in allergy, may partially depend on genetic factors. We evaluated whether genes with immunological functions, i.e. human leukocyte antigen (HLA) II, the protein tyrosine phosphatase, non-receptor type 22 (PTPN22) and filaggrin, modulate immune responses to dietary antigens. METHODS: We analyzed 14 HLA class II haplotypes, the PTPN22 1858 SNP (R620W allele) and 5 known filaggrin null mutations from blood samples of 87 patients with CM allergy (CMA) and 76 control subjects (age 8.0-9.3 years). Serum levels of IgA, IgG, IgG1 and IgG4 antibodies to beta-lactoglobulin, alpha-casein and ovalbumin were measured with enzyme-linked immunosorbent assay, levels of IgE antibodies to CM, ovalbumin and birch with UniCap (Phadia, Uppsala, Sweden). RESULTS: In children with CMA, the HLA (DR15)-DQB1*0602 haplotype was associated with high levels of beta-lactoglobulin-specific total IgG (p < 0.001) and IgG4 (p < 0.001) and alpha-casein-specific total IgG (p = 0.003) and IgG4 (p = 0.002), but not among control subjects. (DR1/10)-DQB1*0501 was associated with lower levels of beta-lactoglobulin-specific total IgG (p < 0.001) and IgG4 (p < 0.001), ovalbumin-specific total IgG (p = 0.002) and IgG4 (p < 0.001), particularly in control subjects (p < 0.001). Six children with eczema (3 with CMA) had the filaggrin mutation del22824. PTPN22 was not associated with specific antibody responses or CMA. CONCLUSION: The HLA II, but not PTPN22 or filaggrin, genotype modulates humoral responses to early food allergens, whereas none of these genes was associated with CMA.

Maternal vitamin D intake during pregnancy is inversely associated with asthma and allergic rhinitis in 5-year-old children.

BACKGROUND: Vitamin D is known to have a number of immunological effects and it may play a role in preventing allergic diseases. Objectives To study the effect of maternal intake of vitamin D during pregnancy on the emergence of asthma, allergic rhinitis (AR), and atopic eczema by the age of 5 years in children with HLA-DQB1-conferred susceptibility for type 1 diabetes. METHODS: Children (1669) participating in the population-based birth cohort study were followed for asthma, AR, and atopic eczema assessed by validated questionnaire at 5 years. Maternal diet was assessed by a food-frequency questionnaire. RESULTS: The mean maternal intake of vitamin D was 5.1 (SD 2.6) microg from food and 1.4 (2.6) microg from supplements. Only 32% of the women were taking vitamin D supplements. When adjusted for potential confounders, maternal intake of vitamin D from food was negatively related to risk of asthma [hazard ratio (HR) 0.80; 95% confidence interval (CI) 0.64-0.99] and AR [HR 0.85; 95% CI 0.75-0.97]. Vitamin D supplements alone were not associated with any outcome. Adjustment for maternal intake of other dietary factors did not change the results. CONCLUSION: Maternal vitamin D intake from foods during pregnancy may be negatively associated with risk of asthma and AR in childhood.

Intake of antioxidant vitamins and trace elements during pregnancy and risk of advanced beta cell autoimmunity in the child.

BACKGROUND: Type 1 diabetes may have its origins in the fetal period of life. Free radicals were implicated in the cause of type 1 diabetes. It was hypothesized that antioxidant nutrients could protect against type 1 diabetes. OBJECTIVE: We assessed whether high maternal intake of selected dietary antioxidants during pregnancy is associated with a reduced risk of advanced beta cell autoimmunity in the child, defined as repeated positivity for islet cell antibodies plus >/=1 other antibody, overt type 1 diabetes, or both. DESIGN: The study was carried out as part of the population-based birth cohort of the Type 1 Diabetes Prediction and Prevention Project. The data comprised 4297 children with increased genetic susceptibility to type 1 diabetes, born at the University Hospital of Oulu or Tampere, Finland, between October 1997 and December 2002. The children were monitored for diabetes-associated autoantibodies from samples obtained at 3-12-mo intervals. Maternal antioxidant intake during pregnancy was assessed postnatally with a self-administered food-frequency questionnaire, which contained a question about consumption of dietary supplements. RESULTS: Maternal intake of none of the studied antioxidant nutrients showed association with the risk of advanced beta cell autoimmunity in the child. The hazard ratios, indicating the change in risk per a 2-fold increase in the intake of each antioxidant, were nonsignificant and close to 1. CONCLUSION: High maternal intake of retinol, beta-carotene, vitamin C, vitamin E, selenium, zinc, or manganese does not protect the child from development of advanced beta cell autoimmunity in early childhood.