Celiac.com 07/29/2010 - The underlying causes of psoriasis are not well understood. Many patients with psoriasis also have a sensitivity to gluten.
In an effort to better understand any connection between psoriasis, celiac disease, and the HLA Cw6 genotype, a research team examined the expression of celiac-associated antibodies gliadin IgA, gliadin IgG, and tissue transglutaminase IgA, and possible associations the antibodies may have with the HLA Cw6 gene in people with psoriasis.
The team included Sangeeta Singh, Gyanendra Kumar Sonkar, Usha, and
Sanjay Singh. They are variously affiliated with the Division of
Immunopathology in the Department of Pathology at the Institute of
Medical Sciences, the Department of Dermatology and Venereology, and
the Academic Staff College at Banaras Hindu University in Varanasi,
Antigens are substances that are recognized by the immune system and trigger an immune reaction.
Class I human histocompatibility (HLA) antigens are coded into a small cluster of structural genes at the C locus on chromosome 6. They show substantially lower immune-triggering action than the HLA-A and -B determinants, and so are not a major factor in medical donations.
Researchers find them useful because of their high-risk association with certain diseases, such as spondylarthritis, psoriasis, multiple myeloma. About 50 percent of all psoriasis patients carry HLC-Cw6.
For the study the team evaluated 56 patients with psoriasis, along with 60 healthy control subjects. The team used ELISA to measure antibody levels, and the microcytotoxicity method to type HLA Cw6.
Blood samples of psoriasis patients showed significant HLA Cw6 expression compared with control subjects (P<0.05).
Psoriasis patients showed substantially higher celiac-associated antibodies for gliadin IgA/IgG and tissue transglutaminase IgA compared with control subjects (P<0.05, <0.05, and 0.01, respectively).
Women showed substantially higher serum anti-tissue transglutaminase IgA (anti tTG IgA) than did men. Older patients showed higher expressions than did their younger counterparts.
Antibodies showed significant positive correlation (anti-gliadin IgA with anti-gliadin IgG: r=0.67, P<0.05; anti-gliadin IgA with anti tTG IgA: r=0.45, P<0.05, anti-gliadin IgG with anti-tTG IgA: r=0.26, P<0.05, respectively), but showed no significant correlation with HLA Cw6.
From their results, the team concludes that patients with psoriasis commonly show latent celiac disease or celiac-associated antibodies, but that HLA Cw6 is not connected with expression of these antibodies in patients with psoriasis. Source: