Monoclonal Antibodies Directed Against Human Lymphoid, Monocytic, and Granulocytic Cells: Reactivities with Other Tissues

Abstract

Monoclonal antibodies (MAbs) reactive with lymphoid cells are not necessarily specific for lymphoid tissues. Forty MAbs with varying degrees of specificity in lymphoid tissue were tested against a wide battery of nonlymphoid human tissues. Cross-reactivity was identified in 18 of 41 antibodies tested. Based on their reactivities, the MAbs were classified in three groups: (1) antibodies with wide reactivities in normal nonlymphoid tissues, i.e., anti-Leu 4, anti-Leu M1, OKT9, anti-HLA-Dr, anti-Leu M2, Mo-2 (Coulter), anti-Leu 7, BA-1, BA-2, BA-3, J5, and A1G3; (2) antibodies with limited reactivities in nonlymphoid tissues (one or two tissues), i.e., OKT6, anti-Leu 10, Mo-1 (BRL), Mo-2 (BRL); and (3) antibodies without cross reactivities in nonlymphoid tissues, i.e., anti-Leu 1, anti-Leu 2a, anti-Leu 3a, OKT3, OKT10, 3A1, anti-Leu 8, TA-1, Lyt 3, B1, B2, OKMo-1, anti-Leu M3, T200. The reactions can be attributed to the presence of a similar, if not identical, epitope in related or different molecules.