Table 2:

Characteristics of different mucin KO models.

KO Model	Similarities Between Muc KO and Wild Type	Characteristics Increased in Muc KO	Characteristics Decreased in Muc KO
Muc1	Viability and fertility[178] Muc2 and Muc4 gene expression[178] Gallbladder size, secretion, and emptying function[179]	Bacterial adherence to epithelium after Helicobacter pylori infection[180] Wound healing rate[182, 183] Pro-inflammatory response[176, 184–186]	Tumor growth rate[177, 178] Gallstone formation[179] Drug resistance (e.g., gemcitabine, etoposide)[188] Absorption of cholesterol[187]
Muc2	Weight gain[190]	Damage in intestinal injury model (e.g., dextran sulfate sodium (DSS))[191] Onset of colorectal cancer[190] Susceptibility to infection[189] Mortality rate[189] Weight loss, mortality, and colonization after Citrobacter rodentium infection[194] Mucosal thickening and superficial erosions[191] Aberrant intestinal crypt morphology, altered cell maturation and migration[190] Pro-inflammatory response [191, 192] Ratio of proliferating to apoptotic cells[190, 191]	Onset of fatty liver disease and obesity with a high fat diet[192] Epithelial barrier integrity after Salmonella Typhimurium infection[189]
Muc5	External ocular appearance[195, 196] Muc1 and Muc4 gene expression[195, 196] Goblet cell number[196] Number of CD45+ immune cells[196]	Susceptibility to Trichuris Muris infection[193] Late onset respiratory problems[195] Expression of Muc5b and Muc4[195–197] Corneal opacification[197]	Clearance of Trichuris Muris[193] Tear quality[197] Body weight[195] Goblet cell number[195]
Muc13	Viability, fertility, development[198]	Onset of acute colitis, macrophage number, and apoptosis in intestinal injury models (e.g., DSS)[198] Tumor necrosis factor (TNF-α) and Interleukin (IL)-1β expression[198]	IL-8 expression after Campylobacter jejuni infection[185]
Muc16	Viability, fertility, and development [199]	IL-6 expression [201] Rate of wound healing[201] Macrophage invasion[201]	Tumor formation and metastasis[200] Pancreatic ductal adenocarcinoma cell proliferation, colony formation and migration in vitro[200] Mucl expression[199]
Muc18		Pro-inflammatory cytokine (KC and TNF-α) expression after Mycoplasma pneumoniae infection[204]	Neutrophillic inflammation and viral load after humanrhino virus 1B (HRV-1B) infection[203] IL-8 expression[202]