9712656 Quinn Many important microbial and cellular processes require a knowledge of the forces with which these entities adhere to surfaces, other cells, and receptor proteins. some of these processes include cell separations, tumor metastasis and wall adhesion, cell seeding for vascular prostheses, etc. Most adhesion assays are very qualitative in nature, frequently due to the irregular nature of the containment "vessels", their small size, and the difficulty in obtaining quantitative data without extensive investment in device development. Adhesion studies are usually done by measuring the force to wash the cell off of the substrate. This SGER proposal seeks to make the process simpler and more quantitative by developing a set of cells of known surface-receptor strength for use in calibrating new measurement vessels and cell receptor systems. The standard cells will be latex beads which have been coated with the appropriate receptor for the experiment and labeled with an identifying tag. The adhesion of the coated latex particles will be determined in the Radial Flow Detachment Assay (RFDA) device that the PI and coworkers have developed over the previous funded grant. The cells of known adhesion (resistance to shear washing force) could then be used to determine more accurately the forces involved in simple washing tests, e.g., washing of cells from coated wells by pipette streams of water. ***
