ANALYSES OF MONOCLONAL-ANTIBODIES REACTIVE WITH PORCINE CD44 AND CD45

Twenty-six monoclonal antibodies (mAbs), assigned to the CD44/CD45 sec tion of the First International Swine CD Workshop, were compared for t heir reactivity against a selected group of target cells by one- and t wo-color flow cytometric analysis. Based on staining and reactivity pa tterns the 26 mAbs were assigned to six groups, group Fl mAbs were des ignated CD44 mAbs; and groups F2 and F3 as CD45 mAbs. With the informa tion available, a CD designation could not be given to the mAbs in gro ups F4, F5 or F6 consisting of four, three and four mAbs each, respect ively. The reactivity of all six mAbs in group Fl (MAC35, 25-32, PORC2 4A, H22A, BAG40A, and BAT31A) was blocked by soluble porcine CD44. One mAb in this group (MAC325) reacted with a cell surface protein with a molecular weight of 80 kDa and was designated as CD44; the other five mAbs were designated as wCD44 because no molecular weight was known. Blocking experiments utilizing a cross reactive anti-human CD44 (mAb Z 062) allowed the definition of the wCD44a epitope recognized by mAbs P ORC24A and H22A. The group F2 mAbs (74-9-3; MAC323; K252.1E4; and 2A5) were designated as CD45 based on their broad reactivity pattern with lymphoid and myeloid cells and their ability to immunoprecipitate thre e