A New Surface Antigen on Human Lymphocytes Defined by the Murine Monoclonal Antibody IVF7

Abstract

The murine monoclonal antibody (MoAb) IVF7 was produced against tumour cells from a patient with a CD3+, CD4+, CD8- T-cell chronic lymphatic leukaemia (T-CLL). The MoAb IVF7 showed reactivity with subpopulations of normal peripheral blood lymphocytes (PBL), as well as with a few cell lines of haematopoietic origin. Thirty-six per cent of PBL were stained with IVF7. Analysing subpopulations, we found that 80% of NK cells, 25% of T cells, and 10-20% of B cells were positive. The myelomonocytic cell line KG-1 was also stained. The molecular weight of the molecule was 40 kDa under reducing conditions. The antigen was found to be trypsin-sensitive. MoAb IVF7 could modulate the antigen from the cell surface. The antibody did not stimulate PBL to DNA synthesis, nor did it significantly influence NK cell-mediated killing.

Characterization of a Monoclonal Antibody Directed Against the Phosphotyrosine Kinase p56lck, in Human T Cells

“…''''1-rabbil anti-mou,sc and horseradish peroxidase nibbil anti-mouse immunoglobulins were obtained from Amersham (Amersham, Bucks, UK) and Dakopatts (Hagersten, Denmark), respectively. The monoclonal antibody IVr7 [7], w;is kindly provided by Dr C. H. Janson (Karolinska Institute, Sweden). Anti-CD3 (OKT3) and anh-CD4 (T4.2) hybndomas were obtained from American Type Culture Collection (Rockville, MD, USA).…”