Figure 4.

Development of desmosomal Ca-Ind occurs gradually in confluent cell culture but does not occur in subconfluent culture. (A) Quantification of acquisition of Ca-Ind. The solid line shows the percentage cells with Ca-Ind desmosomes in monolayers seeded at confluent density and maintained in SM for the times shown. The dotted line indicates lack of formation of Ca-Ind desmosomes, even after 6 d, by cells maintained at subconfluent density, as shown in B and C. (B) Island of cells after 6 d in SM stained for desmoplakin with mAb 11-5F. (C) Cell island similar to that shown in B after treatment with LCM-EGTA for 90 min. Note the complete loss of intercellular contact and desmosomal adhesion between cells in C.