Introduction: Psoriasis (Ps) is a systemic autoimmune disorder that develops under the influence of environmental factors in a genetically susceptible person. The IL-23/IL-17 axis is the primary signalling pathway for cellular and molecular alterations in Ps.
Objective: The aim of the study was to investigate the levels of interleukin 23 (IL-23) in serum and its receptor expression (ILR23) in blood of patients with Ps and psoriatic arthritis (PsA), as well as to evaluate the possibility of using (IL23R) in blood as a marker for susceptibility of Psoriasis.
Patients and Methods: Medical data and clinical evaluation were done and blood samples from patients and control groups were collected. Serum IL-23 concentration was measured using enzyme-linked immunosorbent assay (ELISA) and the Expression of IL-23R in human peripheral blood mononuclear cells (PBMCs) was determined using Western blotting.
Results: Serum IL-23 concentration was significantly higher among Ps cases than in controls and it was significantly different between PsA and Ps groups. The protein expression of IL-23R was significantly greater in Ps group than in control group with no significant difference between Ps and PsA groups. Receiver operating characteristics (ROC) curve showed a diagnostic value for the increased blood IL-23R with a sensitivity of 83.3% and a specificity of 73.3% for psoriasis. Also, (ROC) curve showed a diagnostic value for the increased blood IL-23 with a sensitivity of 80% and a specificity of 73.3% for the diagnosis of psoriasis.
Conclusion: Serum IL-23 and its receptor expression measurements are helpful tools in the diagnosis of Ps as well as in the prediction of PsA. We hypothesized that there is a link between IL-23 and IL-23R and the risk of Ps in addition to PsA, with evidence that the expression of IL-23R is linked to a significantly greater risk of psoriasis.