REPORT ON THE BEHAVIOR OF MONOCLONAL-ANTIBODIES IN THE FIRST INTERNATIONAL PIG CD WORKSHOP IDENTIFYING THE NULL-CELL FAMILIES

Clustering analyses were carried out on data from five independent laboratories testing 22 monoclonal antibodies (mAbs) reacting with CD2(-)sIg(-)lymphocytes on 14 pig blood and/or tissue lymphoid target cells using cytofluorometry. This was coupled with extensive further studies on blood lymphocytes from normal and thymectomised SLAb/b inbred pigs. These mAbs formed two groups: those mainly identifying the large blood-borne thymus-dependent Null T cells (N) and those reacting with tissue and a small number of blood-borne thymus-independent lymphocytes (N'). Based on their tissue cell reaction patterns, the 10 N' mAbs formed three main groups: N' 1 A and B; N' 2 A and B; and N' 3. The 12 N mAbs fell into four groups N4-N7; N6 was divided into subgroups A-D. One N' (032) and two N mAbs (010 and 063) were unclustered. Based on these data, swine workshop cluster numbers were designated to groups N5 (021, 022 and 059) as SWC4, N6 (061 and 117) as SWC5 and N7 (020 and 141) as SWC6, the latter exceptionally as a single antibody, MAC320, since it is the 'type' mAb identifying effectively all blood Null T lymphocytes. Future research and workshops will have to define with a wider range of techniques the relationships, molecular properties and functional roles of the several new, perhaps novel, antigens identified by this family of fascinating, as yet still poorly defined, mAbs.