A mouse monoclonal antibody produced from collagenase digests of human amnion was used by LM and TEM to study the distribution and ultrastructural features of an antigen present in epithelial tissues and in cultured human keratinocytes, and by immunoaffinity chromatography to partially purify the antigen from keratinocyte cell culture media.By immunofluorescence microscopy, the antigen displays a tissue distribution similar to type VII collagen; positive staining of the epithelial basement membrane is seen in skin, oral mucosa, trachea, esophagus, cornea, amnion and lung. Images from rotary shadowed preparations isolated by affinity chromatography demonstrate a population of rod-like molecules 107 nm in length, having pronounced globular domains at each end. Polyacrylamide gel electrophoresis suggests that the size of this molecule is approximately 440kDa, and that it is composed of three nonidentical chains disulfide bonded together.
Deletion of TNFAIP6 Gene in Human Keratinocytes Demonstrates a Role for TSG-6 to Retain Hyaluronan Inside Epidermis
