The severity of IBD correlates with the activation of MAPK and NF-κB as well as the production of proinflammatory cytokines (e.g., IL-6, IL-1β, TNF-α, etc.)in patient macrophages, it was shown that LILRB4, via SHP-1, negatively regulates the activation of the MAPK and NK-κB pathways as well as the production of proinflammatory cytokines during IBD episodes, thus controlling the development of IBD. Here, LILRB4 is linked to inflammatory bowel disease.