PT  - JOURNAL ARTICLE
AU  - Al-Shobaili, Hani A.
AU  - Ahmed, Ahmed A.
AU  - Rasheed, Zafar
TI  - Recognition of oxidized albumin and thyroid antigens by psoriasis autoantibodies
AID  - 10.15537/smj.2015.12.12612
DP  - 2015 Dec 01
TA  - Saudi Medical Journal
PG  - 1408--1419
VI  - 36
IP  - 12
4099  - http://smj.org.sa/content/36/12/1408.short
4100  - http://smj.org.sa/content/36/12/1408.full
SO  - Saudi Med J2015 Dec 01; 36
AB  - Objectives: To investigate the role of reactive-oxygen-species (ROS) induced epitopes on human-serum-albumin (HSA) and thyroid antigens in psoriasis autoimmunity.Methods: This study was performed in the College of Medicine, Qassim University, Buraidah, Saudi Arabia between May 2014 and February 2015. The study was designed to explore the role of ROS-induced epitopes in psoriasis autoimmunity. Singlet-oxygen (or ROS)-induced epitopes on protein (ROS-epitopes-albumin) was characterized by in-vitro and in-vivo. Thyroid antigens were prepared from rabbit thyroid, and thyroglobulin was isolated from thyroid extract. Immunocross-reactions of protein-A purified anti-ROS-epitopes-HSA-immunoglobulin G (IgGs) with thyroid antigen, thyroglobulin, and their oxidized forms were determined. Binding characteristics of autoantibodies in chronic plaque psoriasis patients (n=26) against ROS-epitopes-HSA and also with native and oxidized thyroid antigens were screened, and the results were compared with age-matched controls (n=22).Results: The anti-ROS-epitopes-HSA-IgGs showed cross-reactions with thyroid antigen, thyroglobulin and with their oxidized forms. High degree of specific binding by psoriasis IgGs to ROS-epitopes-HSA, ROS-thyroid antigen and ROS-thyroglobulin was observed. Immunoglobulin G from normal-human-controls showed negligible binding with all tested antigens. Moreover, sera from psoriasis patients had higher levels of carbonyl contents compared with control sera.Conclusion: Structural alterations in albumin, thyroid antigens by ROS, generate unique neo-epitopes that might be one of the factors for the induction of autoantibodies in psoriasis.