Colonic neoplasia and celiac disease: A systematic review

Table 1 Protective factors within the intestinal barrier

Factor	Type	Role in barrier protection	Notes	Ref.
KIF	Cytoskeletal protein	Maintains cytoskeletal structures. Keratin 7 and 20 upregulation leads to crypt widening, while keratin 8 downregulation is observed during inflammation	KIFs are influenced by stress and inflammation. Types 1 (acidic) and 2 (basic) are noted	Helenius et al[10]
Paneth cell granules	Cellular component	Synthesizes and releases antimicrobial peptides to maintain the microbial barrier	Low zinc concentration is associated with granule depletion	Kelly et al[11]
Microbiome environment	Microbial component	Influences the risk of certain diseases, including celiac disease; enteroviral infections are linked to increased disease risk	The intestinal microbiome’s composition and health have systemic effects	Clinton et al[12]
γδ T cells	Immune cells	Reside in the intestinal wall; overactivation and control by IL-15 are crucial for gut homeostasis	Elevated IL-15 expression disrupts gut hemostasis	Suzuki et al[13]
IEL	Immune cells	γ/δ CD3+ and CD8+ IELs are increased in the duodenum of celiac patients, indicating a protective or reactive role	The distribution of IELs varies between the duodenum and colon in celiac patients	[14]

KIF: Keratin intermediate filament; IEL: Intraepithelial lymphocytes; IL: Interleukin.