Humoral immunoreactivity to gliadin and to tissue transglutaminase is present in some patients with multiple myeloma

Similarity of fine specificity of IgA anti-gliadin antibodies between patients with celiac disease and humanized α1KI mice

Gliadins, and primarily α-gliadins containing several sequences such as aa 31-49, aa 56-88 (33-mer), aa 57-68, and aa 69-82, are critical in the induction of immune response or toxic reaction leading to the development of celiac disease (CLD). The role of IgA anti-gliadin antibodies (IgA AGA) is unknown. To this end, we prepared several humanized monoclonal IgA AGA using transgenic α1KI mice. Employing Pepscan with overlapping decapeptides of α-gliadin we observed a robust similarity between the specificity of humanized mouse monoclonal IgA AGA and IgA AGA from patients with florid CLD. The common immunodominant region included several sequential epitopes localized in the N-terminal part of α-gliadin (QFQGQQQPFPPQQPYPQPQPFP, aa 29-50, and QPFPSQQPYLQL, aa 47-58). Notably, IgA AGA produced by clones 8D12, 15B9, 9D12, and 18E2 had significant reactivity against sequences localized in the 33-mer, LQLQPFPQPQ (aa 56-65) and PQLPYPQPQPFL (aa 69-80). Humanized mouse monoclonal IgA AGA that have a known specificity are suitable as standard in ELISAs to detect serum IgA AGA of CLD patients and for studying the AGA pathogenic role in CLD, especially for analyzing the translocation of complex of specific IgA antibodies and individual gliadin peptides through enterocyte barrier.

Breast cancer in lupus

The purpose was to evaluate the frequency of breast cancer (BC) in patients with either systemic (SLE) or incomplete lupus erythematosus (ILE), and possibly to find out immunological differences in patients with and without cancer. 133 consecutive female patients with lupus were included. The records were retrospectively analysed with respect to both malignant disease and routine laboratory parameters (e.g. autoantibodies, white blood cell counts). BC was the most common malignancy that was detected in 50% of female lupus patients with concomitant oncological disease. Other malignancies were significantly less (p < 0.001) frequent. Only ILE-patients had BC or other oncological diseases. The proportion of ILE-patients with SSA- and SSB-autoantibodies was significantly higher (p < 1.5 × 10(-10) and 9.1 × 10(-17)) in those with malignancies than without. The presented data suggest that BC is the most common malignancy in patients with ILE. SLE is no prerequisite to acquire an oncological disease. Immunological disturbances (e.g. SSA- and SSB-autoantibodies) could play a role in the oncogensis.

Different levels of humoral immunoreactivity to different wheat cultivars gliadin are present in patients with celiac disease and in patients with multiple myeloma

Background

Immunity to food antigens (gliadin, cow's milk proteins) is in the centre of the attention of modern medicine focused on the prevention of diseases, prevention which is based on the use of appropriate restriction diet. Detection of the enhanced levels of the immune reactions to antigen(s) present in food is from this point of view of great importance because there are reports that some of health disturbances, like celiac disease (CD) and some premalignant conditions, like monoclonal gammopathy of undetermined significance (MGUS), were vanished after the appropriate restriction diets.

It is well known that gliadin is toxic to small bowel mucosa of relatively small population of genetically predisposed individuals, who under this toxic action develop celiac disease (CD). As the quantity of immunogenic gliadin could vary between different wheat species, the first aim of this work was to determine the percentage of immunogenic gliadin in ten bread wheat cultivars and in three commercially grown durum wheat cultivars. The second part of the study was initiated by results of previous publication, reporting that sera of some of multiple myeloma (MM) patients showed the presence of elevated levels of anti-gliadin IgA, without the enhanced levels of anti-gliadin IgG antibodies, determined with commercial ELISA test. It was designed to assess is it possible to reveal is there any hidden, especially anti-gliadin IgG immunoreactivity, in serum of mentioned group of patients. For this purpose we tested MM patients sera, as well as celiac disease (CD) patients sera for the immunoreaction with the native gliadin isolated from wheat species used for bread and pasta making in corresponding geographic region.

Results

Gliadin was isolated from wheat flour by two step 60% ehanolic extraction. Its content was determined by commercial R5 Mendez Elisa using PWG gliadin as the standard. Results obtained showed that immunogenic gliadin content varies between 50.4 and 65.4 mg/g in bread wheat cultivars and between 20 and 25.6 mg/g in durum wheat cultivars.

Anti-gliadin IgA and IgG immunoreactivity of patients' sera in (IU/ml) was firstly determined by commercial diagnostic Binding Site ELISA test, and then additionally by non-commercial ELISA tests, using standardized ethanol wheat extracts -gliadin as the antigen.

In both patients groups IgA immunoreactivity to gliadin from different cultivars was almost homogenous and in correlation with results from commercial test (except for one patient with IgA(λ) myeloma, they were more then five times higher). But, results for IgG immunoreactivity were more frequently inhomogeneous, and especially for few MM patients, they were more then five times higher and did not correlate with results obtained using Binding Site test.

Conclusion

Results obtained showed different content of immunogenic gliadin epitopes in various species of wheat.

They also point for new effort to elucidate is there a need to develop new standard antigen, the representative mixture of gliadin isolated from local wheat species used for bread production in corresponding geographic region for ELISA diagnostic tests.