In recent years, it has become recognized that many of the problems experienced in initiating cell cultures in vitro with low seeding densities or newly isolated cells are substrate-related. Specifically, studies have found that many of these problems stem from inadequate surface properties found with plastic and glass tissue culture surfaces and lower than optimal levels in nutritive media of serum proteins that specialize in promoting cell adhesion in vivo. When these molecules (fibronectin, laminin, collagen) or related proteins (gelatin, poly-d-lysine) are added to the media, cell attachment and metabolism improve.Recently, a protein (mussel-adhesive protein-MAP) has been isolated from the marine mussel, Mytilus edulis; it appears to have great potential for use as an attachment factor for cells in vitro. It is biocompatible, has high tensile strength, and acts as a cement to secure M. edulis to a variety of substrates in its habitat. In addition, preliminary studies indicate that cell attachment is enhanced in the presence of MAP in vitro. As a result, the experiments within this proposal are designed as a basic study to evaluate the potential of MAP in cell adhesion. Multiple cell types will be plated on MAP and compared to conventional adhesion-promoting factors by comparing attachment efficiency and rate, morphology, and cytotoxicity.National Institute on Aging (NIA)