Infliximab therapy reverses the increase of allograft inflammatory factor-1 in serum and colonic mucosa of rats with inflammatory bowel disease

<p><b>Objective:</b> Our purpose was to study the molecular basis of infliximab (IFX) effect on colon mucosa in a colitis model and to identify new biomarkers of mucosal healing.</p> <p><b>Methods:</b> Healthy rats and rats which were subjected to experimental colitis induced by dextran sulfate sodium, with or without IFX treatment (in the short- and long-term), were studied along with forty-seven IBD patients. Colon mucosal integrity by periodic acid Schiff (PAS) staining, intestinal damage by immunohistochemistry (proliferating cell nuclear antigen, β-catenin, E-cadherin, phosphotyrosine, p-p38, allograft inflammatory factor-1 (AIF-1) and colonic mucosal apoptosis by TUNEL staining were evaluated in rats while serum and colon AIF-1 levels were determined in IBD patients.</p> <p><b>Results:</b> In rats with colitis, IFX reestablished the epithelial barrier integrity, recovered mucus production and decreased colon inflammation, as verified by reduced serum and colon AIF-1 levels; colon and serum AIF-1 levels were also lower in inactive IBD patients compare to active ones. P38 activation after IFX treatment tended to induce differentiation/proliferation of epithelial cells along the colonic crypt-villous axis.</p> <p><b>Conclusions:</b> These findings support AIF-1 as a new biomarker of mucosal healing in experimental colitis and suggest that p38 activation is involved in the mucosal healing intracellular mechanism induced by IFX treatment.</p

DataSheet_1_Poor prognostic factors of pharmacokinetic origin predict outcomes in inflammatory bowel disease patients treated with anti-tumor necrosis factor-α.docx

IntroductionWe evaluated baseline Clearance of anti-tumor necrosis factors and human leukocyte antigen variant (HLA DQA1*05) in combination as poor prognostic factors (PPF) of pharmacokinetic (PK) origin impacting immune response (formation of antidrug antibodies) and disease control of inflammatory bowel disease (IBD) patients treated with infliximab or adalimumab.MethodsBaseline Clearance was estimated in IBD patients before starting treatment using weight and serum albumin concentrations. HLA DQA1*05 carrier status (rs2097432 A/G or G/G variant) was measured using real time polymerase chain reaction. The outcomes consisted of immune response, clinical and biochemical remission (C-reactive proteinResults and discussionIn 415 patients enrolled from 4 different cohorts (median age 27 [IQR: 15-43] years, 46% females), Clearance>0.326 L/day and HLA DQA1*05 carrier status were 2-fold more likely to have antidrug antibodies (OR=2.3, 95%CI: 1.7-3.4; p<0.001, and OR=1.9, 95%CI: 1.4-2.8; p<0.001, respectively). Overall, each incremental PPF of PK origin resulted in a 2-fold (OR=2.16, 95%CI: 1.7-2.7; p<0.01) higher likelihood of antidrug antibody formation. The presence of both PPF of PK origin resulted in higher rates of antidrug antibodies (p<0.01) and lower clinical and biochemical remission (p<0.01). Each incremental increase in PPF of PK origin associated with lower likelihood of endoscopic remission (OR=0.4, 95%CI: 0.2-0.7; p<0.001). Prior biologic experience heightened the negative impact of PPF of PK origin on clinical and biochemical remission (p<0.01). Implementation of proactive therapeutic drug monitoring reduced it, particularly during maintenance and in the presence of higher drug concentrations (p<0.001). We conclude that PPF of PK origin, including both higher Clearance and carriage of HLA DQA1*05, impact outcomes in patients with IBD.</p

Venn´s diagram to select the most relevant molecular processes after GSEA analyses.

<p>A, Incomplete intestinal metaplasia progressing to gastric cancer (IIM-GC). B, Both types of intestinal metaplasia not progressing to gastric cancer (IM-NoGC).</p

Dendrogram and principal component analysis of the analysed samples.

<p>A) Dendrogram showing the hierarchical clustering of the analysed samples. Clustering was based on the overall gene expression values of the studied groups. B) Principal Components Analysis.</p

Heat maps of the analyzed groups.

<p>A) IIM-GC vs IIM-NoGC, B) CIM-GC vs CIM-NoGC, C) IM-NoGC vs Healthy.</p

Venn diagrams of the differentially expressed genes in three different comparisons.

<p>A, Incomplete intestinal metaplasia. B, Complete intestinal metaplasia. IIM-GC or CIM-GC, incomplete or complete intestinal metaplasia progressing to gastric cancer. IIM-NoGC or CIM-NoGC, incomplete or complete intestinal metaplasia not progressing to gastric cancer. Healthy, healthy gastric mucosa.</p

Differentially expressed genes representative of molecular processes in the IM not progressing to GC (IM-NoGC).

<p>Differentially expressed genes representative of molecular processes in the IM not progressing to GC (IM-NoGC).</p

Differentially expressed genes with oncogenic functions in the CIM progressing to GC (CIM-GC).

<p>Differentially expressed genes with oncogenic functions in the CIM progressing to GC (CIM-GC).</p

Differentially expressed genes with oncogenic functions in the IIM progressing to GC (IIM-GC).

<p>Differentially expressed genes with oncogenic functions in the IIM progressing to GC (IIM-GC).</p

Validation by RT-qPCR of some differentially expressed genes obtained in the microarray analysis.

<p>Comparison of the expression level (fold change) by microarray analysis and by RT-qPCR of significant differentially expressed genes in the IIM-CG versus IIM-NoGC, CIM-GC versus CIM-NoGC and IM-NoGC versus healthy gastric mucosa.</p