Trellis Bioscience of South San Francisco has partnered with PDL BioPharma Inc. of Fremont, Calif. Under the terms of the agreement, the former will use its CellSpot technology to search for monoclonal antibodies directed against an antigen from the latter, which will conduct further research on the antibodies found. The device combines software and digital microscopy to simultaneously analyze cells along more than 15 parameters. Trellis will receive an upfront fee, milestone payments and royalties on any products developed and commercialized by PDL.