The aim of our case-control study was to identify novel biomarkers of Crohn's disease (CD) that hold the potential to be employed in both disease diagnosis and monitoring activity. In the context of the contribution of intestinal barrier integrity and immune response to the pathogenesis of CD, we assessed the serum concentrations of proguanylin (pro-GN), pentraxin 3 (PTX3) and S100A12 in 20 patients before and after anti-inflammatory treatment, as well as in 20 healthy individuals. Statistical analyses revealed a significant difference in the levels of pro-GN (5.5 vs. 11.35, p < 0.001), PTX3 (2117.9 vs. 1608.37, p < 0.05) and S100A12 (79.4 vs. 19.74, p < 0.001) between pretreatment patients with CD and healthy individuals. Moreover, we noted a significant relationship between the serum profile of PTX3 and disease activity, expressed as CDAI, both before (p < 0.005, r = 0.63) and after (p < 0.05, r = 0.60) treatment. A similar correlation was noted in the case of S100A12 (p < 0.005, r = 0.81), albeit exclusively within the post-treatment group of patients. Anti-inflammatory treatment resulted in an elevation of pro-GN concentration (5.5 vs. 8.04, p < 0.001) and a reduction in PTX3 level (2117.9 vs. 1609.5, p < 0.05) in the serum of patients with CD. In comparison to our previous research conducted on a group of patients with ulcerative colitis (UC), those with CD exhibited reduced levels of PTX3 (2117.9 vs. 3197.05, p < 0.005) and elevated concentrations of S100A12 (79.4 vs. 39.36, p < 0.05). The results obtained from this investigation suggest that measurements of pro-GN, PTX3 and S100A12 could prove beneficial in the diagnosis of Crohn's disease. Assessment of changes in the serum profile of PTX3 appears to be a good marker of response to treatment but also, along with analysis of S100A12 protein serum levels, a useful marker in differentiating CD from UC.
Keywords: Crohn disease; PTX3 protein; S100A12 protein; colitis; inflammation; intestinal mucosa; neutrophils; proguanylin; ulcerative.