5:28 PM 10/7/97 Does any body have a construct encoding a cell surface marker (e.g. CD20) for co-transfection of mammalian cells? We urgently need some for our experiments. Thank you very much! Ri-Yao Yang, Ph.D. Division of Allergy La Jolla Institute for Allergy and Immunology 10355 Science Center Drive San Diego, CA 92121