Antiadhesive function of 130-kd glycoform of CD43 expressed in CD4 T-lymphocyte clones and transfectant cell lines

Conflicting findings regarding proadhesion and antiadhesion in cell-to-cell interactions were previously reported for CD43, We examined possible diffe rences in the role of the 130-kd glycoform and the 115-kd glycoform of CD43 in cellular adhesion in vitro. We generated a monoclonal antibody (MFT3) t hat discriminates between helper and non-helper murine T-cell clones. Chara cterization of MFT3 with use of biochemical analysis and complementary DNA (cDNA) transfection experiments showed that it is specific for the 130 kd g lycoform of CD43, T-cell clones that expressed the 130-kd CD43 glycoform sh owed decreased homocytic aggregation and decreased adhesion to spleen cells , B-lymphoma cell lines, and fibroblastic cell lines compared with T-cell c rones negative for the 130-kd glycoform, Expression of core 2 beta -1, 6-N- acetylglucosaminyl-transferase (C2GnT) cDNA together with CD43 cDNA resulte d in expression of both the 130-kd CD43 glycoform and the 115-kd CD43 glyco form in fibroblastic cell lines. Using these cell lines, we showed that the 130-kd glycoform but not the 115-kd glycoform of CD43 has an antiadhesive function in cellular interactions. Our findings suggest that the antiadhesi ve function of CD43 is primarily carried out by the 130-kd glycoform. (C) 2 000 by The American Society of Hematology.