IL-33 promotes gastric tumour growth in concert with activation and recruitment of inflammatory myeloid cells

Abstract

Interleukin-33 (IL-33) is an IL-1 family cytokine known to promote T-helper (Th) type 2 immune responses that are often deregulated in gastric cancer (GC). IL-33 is overexpressed in human gastric tumours suggesting a role in driving GC progression although a causal link has not been proven. Here, we investigated the impact of IL-33 genetic deficiency in the well-characterized gp130F/F mouse model of GC. Expression of IL-33 (and it's cognate receptor, ST2) was increased in human and mouse GC progression. IL-33 deficient gp130F/F/Il33-/- mice had reduced gastric tumour growth and reduced recruitment of pro-tumorigenic myeloid cells including key mast cell subsets and type-2 (M2) macrophages. C..