Fig. 9.

Tenectin VFC#3 andVFC#5 support PS2-mediated cell adhesion. Untransformed (S2) cells or the same expressing PS2m8 (αPS2m8βPS) and PS2c (αPS2cβPS) integrins were allowed to adhere to tenectin VWC#3 (A) or VFC#5 (B). The tenectin fusion proteins used were either wild type (WT) or the same whose potential integrin binding motifs had been mutated; RGD or RSD>SSL (SSL in A and B respectively); RDD>ATA (ATA); RYE>TYI (TYI). Adhesion was defined by the number of cells remaining attached after washing, 20 minutes after settling on the plate. The number of cells was determined by staining the cells with crystal violet and dye levels were determined using a microplate reader. To obtain tenectin dependent adhesion values, background adhesion observed in wells coated with BSA was subtracted. Three wells were scored for each ligand and the values are the mean ± s.e.m. of these three values. Differences between S2 cells and PS2m8 cells on VWF#3, between both PS2m8 cells and PS2c cells on VWF#3 wild type verses RGD>SSL, and PS2c cells on wild type VWF#5 verses RDD>ATA were significant (P< 0.05). Consistent, but less dramatic, were the differences between PS2c cells and S2 cells on VWF#3 (P=0.06), PS2c cells and S2 cells on VWF#5 (P=0.10), PS2m8 cells on wild type VWF#5 verses RDD>ATA (P=0.09), PS2m8 cells and S2 cells on VWF#5 (P=0.13).