Mass spectrometric determination of IgG subclass-specific glycosylation profiles in siblings discordant for myositis syndromes.

Many autoimmune conditions are believed to result from chronic inflammation as a consequence of the interaction of genetic and environmental factors in susceptible individuals. One common feature in some autoimmune diseases is the decrease in terminal galactosylation of the constant region N-glycan of the total plasma immunoglobulin. To determine whether a similar pattern is characteristic for the autoimmune disorder myositis, we analyzed the antibody subclass specific glycosylation in patients with myositis, their asymptomatic siblings, and healthy unrelated age- and sex-matched controls. The antibody subclass specific glycosylation was determined from the LC-MS analyses of the IgG glycopeptides generated by trypsin digestion of the antibody heavy chain. The glycosylation profiles of the IgG subclasses were determined relative to the total abundance of all glycoforms. We found elevated amounts of glycoforms lacking terminal galactose in myositis patients. Pairwise statistical analyses reveals that galactosylation is statistically different between the myositis patients and control groups. Furthermore, the trend analysis for glycosylation indicates a pattern of decreasing galactosylation in the order controls ≥ siblings ≥ myositis patients, suggesting the existence of a genetic, immune-related predisposition in the group of asymptomatic siblings that can be detected before the onset of clinical symptoms at the level of plasma proteins.

Risk of asthma in adult twins with type 2 diabetes and increased body mass index.

AIM: To examine the relationship between asthma, type 2 diabetes and increased body mass index (BMI) in adult twins. METHODS: We performed record linkage between questionnaire-defined asthma and BMI, and hospital discharge diagnoses of type 2 diabetes in 34,782 Danish twins, 20-71 years of age. RESULTS: The risk of asthma was increased in subjects with type 2 diabetes relative to nondiabetic subjects both in men (13.5%vs 7.5%), P = 0.001 and in women (16.6%vs 9.6%), P = 0.001. The result remained significant after adjustment for age, BMI, smoking, symptoms of chronic bronchitis, marital status and zygosity, men: OR = 1.70 (1.07-2.70), P = 0.026; women: OR = 1.88 (1.24-2.85), P = 0.003. In this analysis, BMI remained a highly significant predictor for asthma independently of diabetes status in women, P < 0.000 but not in men, P = 0.336. Significant positive genetic correlations were found between asthma and type 2 diabetes, 0.20 (0.01-0.40), P = 0.047; between asthma and BMI in women, 0.15 (0.07-0.22), P < 0.000; and between BMI and type 2 diabetes, 0.40 (0.29-0.43), P < 0.000. CONCLUSIONS: Asthma, type 2 diabetes and increased BMI are strongly associated in adults, particularly in women. These results suggest a common aetiology for asthma and metabolic syndrome.

Immunization with a recombinant MAGE-A3 protein after high-dose therapy for myeloma.

MAGE-A3 is frequently expressed in high-risk multiple myeloma (MM). We immunized a healthy donor with MAGE-A3 protein formulated in AS02B to transfer immunity to her identical twin, diagnosed with MAGE-A3-positive MM. After a melphalan 200 mg/m syngeneic peripheral blood stem cell transplant, primed donor cells collected after immunizations were transferred and followed by repeated patient immunizations. MAGE-A3 immunizations were well tolerated. Strong MAGE-A3-specific antibody, cytotoxic T-lymphocyte (CTL), and T-helper responses were induced in both twins. A humoral response was transferred to the patient with the donor peripheral blood stem cells and increased by booster immunization. The CTL response targeted a previously undescribed HLA-A*6801 binding MAGE-A3115-123 peptide. MAGE-A3115-123 CTLs were detected in the patient more than 1 year after the last immunization. Multiple T-helper cellular responses were detected with the dominant response to an HLA-DR11 restricted MAGE-A3 epitope. The patient remains in remission 2.5 years after the second transplant. This report shows for the first time that immunization of a healthy donor with a defined cancer-testis protein induces immune responses that can be transferred and expanded posttransplant in the recipient. MAGE-A3 immunization may be a useful adjunct to high dose melphalan-based peripheral blood stem cell transplant, providing a new therapeutic option for high-risk MM.

Changes occurring in immune responsiveness of single- and twin-bearing Comisana ewes during the transition period.

Changes induced by twin and single lambing in the immune response of 16 periparturient Comisana ewes were studied. Cell-mediated immune responses were evaluated by means of skin tests performed from 3 wk before and up to d 35 after parturition. At d 21 and 7 before lambing, the sheep received an intramuscular injection of the antigen keyhole limpet hemocyanin (KLH), to which the animals had not been previously exposed, to determine their humoral immune response. Starting 3 wk before lambing and up to d 35 postlambing, the ewes were sampled to determine the plasma concentrations of anti-KLH antibody (IgG), IL-6, and IL-1 beta. From parturition through d 35 postpartum, individual milk samples were collected for determination of anti-KLH IgG titers and IL-6 and IL-1beta concentrations by means of a capture ELISA. The number of lambs born affected IL-6 concentrations in ewe plasma; IL-6 secretion always was higher in ewes birthing twins than in single-lambing ewes. Apart from the number of lambs born, the concentrations of plasma IL-6 in ewes were higher at lambing than at d 21 antepartum and at d 35 postpartum. An interaction of number of lambs born x time of sampling was observed for plasma antibody titers to KLH. The IgG concentrations were significantly higher in single-bearing ewes than in twin-bearing ewes before parturition and were very similar across groups after parturition. A time effect was found for the cell-mediated immune response and for anti-KLH IgG concentrations in milk, such that at parturition, cellular responses were lowest, and the anti-KLH IgG concentration was highest. A significant correlation was found for IgG titers to KLH in plasma and milk. Results indicate that IL-6 concentrations in blood can be considered a reliable indicator of stress connected to lambing and that the mammary gland is a microenvironment unrelated to blood stream with respect to interleukins expression. In contrast, a relationship was found for the IgG secretions in milk and blood, which suggests that the assessment of humoral immune status may be combined with milking routine in dairy animals.

Hunting for immune response regulatory genes: vaccination studies in infant twins.

The contribution of twin studies towards unraveling the complex mechanisms of multifactorial diseases is increasingly recognized. Recent twin studies using infant vaccination as a model for infectious diseases have confirmed the importance of host genetic factors as major regulators of the immune response. A combination of twin-based family studies and population-based association studies should lead to the identification of the specific genes involved. These genes and their products have the potential to be developed as targets for novel therapeutic and prophylactic agents against infectious diseases.

Hepatitis B surface antigen presentation and HLA-DRB1*- lessons from twins and peptide binding studies.

The aim of this study was to investigate the underlying mechanisms of the genetic association between certain HLA-DRB1* alleles and the immune response to HBsAg vaccination. Therefore, HBsAg peptide binding to HLA-DR molecules was measured in vitro by peptide binding ELISAs. Additionally, HBsAg-specific T cell reaction and cytokine profile of immune response were analysed ex vivo in ELISPOT assays and DR-restriction of T-cell proliferative responses was investigated with HBsAg specific T cell clones. In addition, we compared HBsAg specific T cell responses of 24 monozygotic and 3 dizygotic twin pairs after HBsAg vaccination. Our results showed that the peptide binding assays did not reflect antigen presentation in vivo. DR alleles associated with vaccination failure like DRB1*0301 and 0701 efficiently presented HBsAg peptides. In 11 of 24 investigated monozygotic twin pairs we observed pronounced differences in the recognition of HBsAg peptides. This study indicates that HLA-DR associations with HBsAg vaccination response are not caused by differences in peptide binding or by a shift in the Th1/Th2 profile. Our findings strongly argue for differences in the T cell recognition of peptide/MHC complexes as the critical event in T cell responsiveness to HBsAg.

Quantitative association tests of immune responses to antigens of Mycobacterium tuberculosis: a study of twins in West Africa.

There is now considerable evidence that host genetic factors are important in determining the outcome of infection with Mycobacterium tuberculosis (MTB). The aim of this study was to assess the role of several candidate genes in the variation observed in the immune responses to MTB antigens. In-vitro assays of T-cell proliferation, an in-vivo intradermal delayed hypersensitivity response; cytokine and antibody secretions to several mycobacterial peptide antigens were assessed in healthy, but exposed, West African twins. Candidate gene polymorphisms were typed in the NRAMP1, Vitamin D receptor, IL10, IL4, IL4 receptor and CTLA-4 genes. Variants of the loci IL10 (-1082 G/A), CTLA-4 (49 A/G) and the IL4 receptor (128 A/G) showed significant associations with immune responses to several antigens. T-cell proliferative responses and antibody responses were reduced, TNF-alpha responses were increased for subjects with the CTLA-4 G allele. The T-cell proliferative responses of subjects with IL10 GA and GG genotypes differed significantly. IL4 receptor AG and GG genotypes also showed significant differences in their T-cell proliferative responses to MTB antigens. These results yield a greater understanding of the genetic mechanisms that underlie the immune responses in tuberculosis and have implications for the design of therapeutic interventions.

[Haemolytic disease of the newborn--from a mother with anti-Kell, anti-E and anti-Vel anti-erythrocyte alloantibodies]. / Morbus Haemolyticus Neonatorum (MHN) -- Hämolytische Krankheit des Neugeborenen von Mutter mit Anti-Kell, Anti-RhE und Anti-VEL Antierythrozytären Alloantikörpern.

A grave form of HDN (haemolytic disease of the new-born) is described in female twins, caused by Kell, E and Vel isoimmunisation. The weakly vital and anaemic new-born babies were hospitalised with signs of respiratory distress on the first day of their life after the delivery by Caesarean section in the 38 (th) week of pregnancy in the General Hospital Dubrovnik. Already during the first hours of their life jaundice developed with a high bilirubin level for their age. The direct Coombs' test on the twins and the indirect Coombs' test on the mother were positive. Immuno-haematological analysis proved the presence of anti-Kell, anti-E and the very rare anti-Vel antibodies in the mother's serum and in the plasma of both twins. We had no possibility to obtain appropriate blood for the indicated exsanguine transfusion because cross-probes with the accessible blood samples were positive. Up to the fourteenth day of life the anaemia deepened and was aggravated in one twin, the Kell positive one (phenotype CcDEe,Kk) in relation to the other, the Kell negative (phenotype CcDEe,kk) twin. The recovery of the female twins started on the 15 (th) day of life, after the transfusion of blood (phenotype: 0,ccddee, Vel negative, Kel negative), received from the bank of rare blood groups in London. This is the first described case of haemolytic disease of the new-born caused by antibodies on the antigen Kell, E and Vel. The low frequency of immunisation with rare antigens such as Kell, E and Vel, does not exclude the possibility of the occurrence of grave forms of haemolytic disease. All pregnant women with a positive indirect Coombs' test should be further immuno-haematologically tested in order to identify the antibodies type so that the treatment of the new-borns could be commenced in time.