Maryam Valizadeh - Department of Medical Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran;
Arman Ahmadzadeh - Department of Rheumatology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Mousa Behzadi - Department of Medical Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran;
Farshid Yeganeh - Department of Medical Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran;

Systemic lupus erythematosus (SLE) is a complex autoimmune disease which involves several organs.CD26 is a multifunctional molecule that has an extracellular domain with dipeptidyl peptidase IV activity which digests crucial inflammatory molecules. CD26 plays an important role in T-cell activation and enhances immune responses. This study was carried out to evaluate the level of CD26 gene expression in SLE patients. Forty-six SLE patients and 44 healthy controls voluntarily participated in this study. Based on the SLE disease activity index (SLEDAI), the patients were divided into two subgroups, those with active disease (n=24) and those with inactive disease (n=22). Patients were also subgrouped according to renal involvement, as those with lupus nephritis (n=17) and those without lupus nephritis (n=29). Their CD26 mRNA levels in peripheral blood cells were analyzed by quantitative RT-PCR. CD26 mRNA expression increased 3.6-fold in SLE patients in comparison with the controls (p<0.0001). No difference was found in the level of CD26 mRNA among the subgroups of the SLE patients with the active or inactive form of the disease (p> 0.05). Although CD26 mRNA expression in patients with lupus nephritis was 2.76-fold higher than those without nephritis, the difference was not statistically significant (p> 0.05). CD26 gene expression in peripheral blood cells of SLE patients significantly increased over that of the controls. This increase was not affected by the disease activity nor did it show any significant correlation with complications in organs.

dipeptidyl peptidase IV, Gene expression, Systemic lupus erythematosus