RETRACTED ARTICLE: The profile of the key pro-inflammatory cytokines in the serum of patients with CD and their association with the disease severity and activity

Abstract

Background The epidemiology of Crohn’s disease (CD) has changed over the past decades, demonstrating a trend toward increased prevalence in developing countries, while in developed countries, its incidence has stabilized. The study aimed to examine the profile of the key pro-inflammatory cytokines in the serum of patients with CD and establish their association with the severity and activity of the disease. Methods A total of 61 patients (29 women (47.5%), 32 men (52.5%) aged from 18 to 40 years (mean age (30.42 ± 2.51) years) with the verified diagnosis of CD in the active phase were examined. The control group consisted of 30 healthy people of corresponding age. Results CD is characterized by a reliable increase of pro-inflammatory cytokines in blood compared to healthy people: tumor necrosis factor-α (TNF-α) – by 4.45 times (137.46 ± 9.72 vs. 30.88 ± 2.08 pg/ml in healthy people, p < 0,001), interleukin-1α (IL-1α) – by 5.08 times (51.55 ± 4.36 vs. 10.14 ± 0.93 pg/ml, p < 0.001), interleukin-6 (IL-6) – by 2.16 times (20.03 ± 1.81 vs. 9.27 ± 0.52 pg/ml, p < 0.001), interleukin-8 (IL-8) – by 2.04 times (25.74 ± 2.05 vs. 12.62 ± 1.16 pg/ml, p < 0.001), and interferon-γ (IFN-γ) – by 5.30 times (208.63 ± 14.29 vs. 39.35 ± 2.40 pg/ml, p < 0.001). The authors have established direct correlations between the Crohn's disease activity index and blood content of TNF-α (r = 0.84, p < 0.013), INF-γ (r = 0.61, p < 0.028); between TNF-α and INF-γ content (r = 0.67, p < 0.023), IL-1α (r = 0.49, p < 0.042), IL-6 (r = 0.40, p < 0.045), and IL-8 (r = 0.51, p < 0.033); INF-γ and IL-1α (r = 0.53, p < 0.040), IL-6 (r = 0.37, p < 0.039), IL-8 (r = 0.44, p < 0.040). Conclusions Patients with CD were found to have multiple cytokines (TNF-α, IL-1α, IL-6, IL-8, and IFN-γ,). The content of cytokines correlated positively with the CD activity index.