|
Main functions: surfactant delivery and epithelial repair |
||
| Function/product |
Functional significance |
Reference |
|
|
||
| Surfactant |
||
| Synthesis |
||
| Components of surfactant |
||
| Phospholipids |
Surface activity |
[186] |
| Surfactant proteins |
||
| A |
Tubular myelin formation |
[71,187,188] |
| Defence |
[33] |
|
| B |
Absorption of lipid to monolayer |
[71,189] |
| C |
[86] |
|
| D |
Defence |
[34,190] |
| Components secreted together with surfactant |
||
| Lysozyme |
Defence |
[35,191] |
| Plasmalogens |
Protection against oxidation |
[192] |
| Cathepsin H |
||
| Maturation |
||
| Intracellular cathepsin H |
Processing of SP-B |
[194] |
| Processing of SP-C |
[50] |
|
| Secretion |
||
| Signal receptors |
||
| β-adrenergic receptors |
[195,196] |
|
| P1 purinoreceptors |
[197,198] |
|
| P2Y purinoreceptors |
[198,199] |
|
| Components of exocytosis apparatus |
||
| Microtubules |
[65] |
|
| Actin |
[66] |
|
| Annexin II |
[200] |
|
| Annexin IV |
[201] |
|
| Annexin VII (= Synexin) |
[202,203] |
|
| Extracellular transformation |
||
| α1-antitrypsin |
[2048] |
|
| Convertase |
Conversion of lipid monolayer into vesicles |
[88,89,205] |
| Recycling |
||
| Receptor of SP-A |
[206] |
|
| Lamellar body lysosomal enzymes |
||
| Alkaline phosphatase |
Marker of type II cells |
[207] |
| α-glucosidase |
[208] |
|
| α-mannose |
[208] |
|
| Alveolar epithelial repair |
||
| Proliferation |
||
| Cyclin A |
[209] |
|
| Cyclins D1, D2 |
Proliferation, differentiation |
[210] |
| Cyclin dependent phosphokinases |
Proliferation, differentiation |
[210] |
| PTHRP |
Inhibition of proliferation |
[211] |
| Calmodulin |
Proliferation, differentiation |
[212,213] |
| Insulin-like growth factor (IGF)-binding protein2 |
G1-arrest |
[214] |
| Differentiation |
||
| Retinoic acid receptor |
Inhibition of differentiation |
[215] |
| Aminopeptidase N |
[216] |
|
| Apoptosis |
||
| CD95 (receptor of Fas-ligand) |
[134] |
|
| Fas-ligand |
[138] |
|
| Bax |
Pro-apoptotic peptide |
[217] |
| Bcl-2 |
Anti-apoptotic peptide |
[138] |
| Caspase-3 |
Execution caspase |
[138] |
Fehrenbach Respiratory Research 2001 2:33 doi:10.1186/rr36 |
||