Table 2.
The distribution of epithelial tissue functions onto component cell types corresponding to Figure 1
| Function | Airway cell type | Specific role | Small intestinal cell type | Specific role |
|---|---|---|---|---|
| Nutrient absorption | N/A | Enterocyte | Absorption of carbohydrates (e.g., Lct) and lipids, bile resorption | |
| Vectorial transport | Ciliated cells | Directional propulsion of mucus | N/A | |
| Fluid regulation | Ionocyte | Chloride (Cftr), sodium (ENaC), potassium (Kcnma1) transport | Enterocyte | Sodium (Slc5a1, Sglt1) |
| Sensation | Tuft cells | Chemosensation, possible innervation | Tuft cells | Chemosensation of parasites (Trpm5, Gnat3) |
| PNEC | Oxygen sensation, stretch, innervation | Enterochromaffin cells | Detection of irritants, metabolites, and catecholamines | |
| Neuromodulation | PNEC | Hormones, innervated | Enterochromaffin | Serotinergic activation of sensory nerves (Tph1, Tac1) |
| Tuft-1 | Neurotransmitter production (ChAT) | Enteroendocrine | Regulation of satiety (Ghrelin, Pyy) and mood (Gastrin, Cck) | |
| Tuft-1 | Neurotransmitter production (ChAT) | |||
| Immunomodulation | PNEC | Allergic response (Cgrp, Gaba) | Enteroendocrine cells | Cck, Glp-1 substance P, neurokinin A, and neurokinin B |
| Tuft-2 | Allergic response (leukotrienes, IL-25, Tslp) | Tuft-2 | Leukotrienes, Il25, Tslp | |
| Club | Tnf | Paneth | Tnfα | |
| Enterocytes | Il18 | |||
| Mucus production | Goblet | Mucins (Muc5b, Muc5ac) | Goblet cells | Mucins (Muc2) |
| Antigen presentation | Microfold cells | Microfold cells Intestinal stem cells | ||
| Goblet | ||||
| Production of new cells | Basal cells | Production of club and rare cell types | Intestinal stem cells | Production of transit-amplifying cells, Paneth cells |
| Production of differentiation factors to club cells | Transit-amplifying | Production of differentiated cells | ||
| Club cells | Production of ciliated cells and goblet cells | Paneth cells | Stem cell niche factors WNT (Wnt3,11), Notch (Dll4) | |
| Hillock basal cells | Production of hillock club cells | |||
| PNEC | Reserve stem cell | |||
| Antimicrobial secretion | Ionocytes | Secretion of cochlin | Paneth cells | Antimcrobial peptides—α defensins, lysozyme, angiogenin4, Mmp7, interlectin-1 |
| Club | Surfactants (Sftpd, Scgb3a2), antimicrobial (Ltf, Lyz2) | Enterocytes | Antimcrobial peptides—C-type lectins (Reg3b, Reg3g) | |
| Hillock club | Surfactants (Sftpd), antimicrobial (Ltf, Lyz2) | |||
| Goblet | Goblet | Antiparasitic immunity—Retnlb |