Inflammatory cytokines: from discoveries to therapies in IBD

ABSTRACT

Introduction: Although the etiology of inflammatory bowel diseases (IBD) remains unknown, accumulating evidence suggests that the intestinal tissue damage in these disorders is due to a dynamic interplay between immune cells and non-immune cells, which is mediated by cytokines produced within the inflammatory microenvironment.

Areas covered: We review the available data about the role of inflammatory cytokines in IBD pathophysiology and provide an overview of the therapeutic options to block the function of such molecules.

Expert opinion: Genome studies, in vitro experiments with patients’ samples and animal models of colitis, have largely advanced our understanding of how cytokines modulate the ongoing mucosal inflammation in IBD. However, not all the cytokines produced within the damaged gut seem to play a major role in the amplification and perpetuation of the IBD-associated inflammatory cascade. Indeed, while some of the anti-cytokine compounds are effective in some subgroups of IBD patients, others have no benefit. In this complex scenario, a major unmet need is the identification of biomarkers that can predict response to therapy and facilitate a personalized therapeutic approach, which maximizes the benefits and limits the adverse events.

KEYWORDS:

• Crohn’s disease
• ulcerative colitis
• IL-12
• IL-23
• JAK/STAT
• TNF
• tofacitinib
• ustekinumab

Article highlights

• Many cytokines contribute to amplify and sustain the tissue-damaging inflammatory response in IBD.

• Several compounds targeting effector cytokines are effective in inducing and maintaining remission in IBD patients.

• Not all patients respond to therapy and others lose response over time, highlighting the complexity of IBD pathogenesis.

• The identification of biomarkers could help improve treatments’ outcome.

This box summarizes key points contained in the article.

Declaration of interest

G Monteleone has filed a patent related to the treatment of inflammatory bowel diseases with Smad7 antisense oligonucleotides and has served as an advisory board member for ABBVIE. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Additional information

Funding

This paper was not funded.