Either your web browser doesn't support Javascript or it is currently turned off. In the latter case, please turn on Javascript support in your web browser and reload this page. Current Opinion in Gastroenterology , 01 Jan , 29 1 : DOI: Review Free to read. Inflammatory bowel diseases IBDs; e. The observed link between eosinophil levels and severity and remission rates in IBD has led to speculation that eosinophils may contribute to the antimicrobial inflammatory response in IBD.
Eosinophils express the necessary cellular machinery innate immune receptors, pro-inflammatory cytokines, antibacterial proteins and DNA traps to mount an efficient antibacterial response; however, the rapid decline in eosinophil numbers following acute systemic bacterial infection suggests a very limited role for eosinophils in bacterial responses.
We describe the clinical evidence of eosinophil involvement in IBD; summarize the in vitro and in vivo evidence of eosinophil anti-bacterial activity and the biology of eosinophils focusing on eosinophil-mediated bactericidal mechanisms and the involvement of eosinophil-derived granule proteins in this response; and conceptualize the contribution of eosinophils to an anti-commensal bacterial response in IBD.
While the precise etiologies of inflammatory bowel disease IBD e. Evidence indicates that the commensal intestinal microbiota are important to the exacerbation of the IBD phenotype: surgical diversion of the fecal stream effectively resolves CD inflammation distal to the surgical site [ 4 ], and treatment with antibiotics decreases the risk of post-operative recurrence of CD [ 5 ].
A common feature of the cellular infiltrate in IBD, particularly UC, is eosinophils [ 6 , 7 ], While this cell population usually represents only a small percentage of the infiltrating leukocytes, eosinophil level has been shown to correlate with morphological changes to the gastrointestinal GI tract, disease severity and GI dysfunction [ 8 — 11 ]. Collectively, this clinical and experimental evidence suggests that eosinophils may play a role in combating commensal intestinal microbiota and infection in intestinal diseases such as IBD.
