TNF and inflammatory bowel disease: One hypothesis as to why this was observed is while eosinophils produce TNF-alpha, anti-TNFs such as adalimumab block TNF-alpha but do not act further upstream.10,11 On the contrary, IL-23 has been linked to eosinophil production.12 This may suggest that targeting the IL-23 pathway may be more effective in managing eosinophil-associated inflammation in IBD compared to targeting TNF-alpha alone.