Optimized hookworm-derived biologic, AIP-2 restores mucosal tolerance and down-regulates colon cancer-associated gene expression in TNBS-induced colitis.

The development of treatments for ulcerative colitis (UC) has seen significant advancements over recent years, focusing on new drugs, innovative approaches, and a deeper understanding of the disease mechanisms. Few however have been able to restore natural tolerance. The hookworm-derived recombinant Anti-Inflammatory Protein (AIP)-2 has been previously shown to have promising pro-tolerogenic characteristics against asthma. Here we show that AIP-2 suppresses weight loss, colon damage, mucosal erosion and necrosis as well as the suppression of pro-inflammatory cytokines IL-6 and IFN-γ in a TNBS-induced model of UC. Following sequence optimization and efficacy comparison, we have generated the construct AIP-2 which contains the N-terminal sequence and an amino acid substitution (asparagine to glutamine) at position 48 to remove the N-glycan. AIP-2 significantly suppressed colon Th1/Th17 pathways and promoted regulatory T cells via TGF-β, IL-10 and ICOSL signaling in colon tissues. Transcriptomics analysis revealed differential expression of genes from the TNF receptor superfamily, TNF-α-induced genes and aldehyde dehydrogenase (ALDH) encoding enzymes which promoted tissue repair and the suppression of colorectal cancer-causing pathways. This suggests that AIP-2 promotes Treg/Th17 balance that could potentially offer a novel disease modifying therapeutic opportunity against UC.