CADHERIN FUNCTION IS REQUIRED FOR HUMAN KERATINOCYTES TO ASSEMBLE DESMOSOMES AND STRATIFY IN RESPONSE TO CALCIUM

Elevation of the calcium concentration in keratinocyte culture induces the rapid organization of adherens junctions and desmosomes. Formatio n of these intercellular junctions is accompanied by reorganization of the cytoskeleton and, with a more delayed timecourse, stratification of the culture into a multilayered epithelial cell sheet. Keratinocyte s express two cadherins, known as E- and P-cadherin, which are the cel l-cell adhesion molecules of the adherens junction. Antibody that bloc ks E-cadherin function delays the calcium-induced formation of both ad herens junctions and desmosomes and, leads to an abnormally stratified culture. In the present study, we show that anti-E-cadherin plus anti -P-cadherin antibodies inhibit the formation of adherens junctions and desmosomes, prevent reorganization of the cytoskeleton, and block str atification. These studies indicate that cadherin function is required for the calcium-induced intercellular junction organization and strat ification of human keratinocytes in vitro.