PMID: 9439978Jan 1, 1997Paper

An anti-LFA-1 monoclonal antibody (LDA-8) induces cellular aggregation of human lymphoblastoid cell lines and peripheral blood lymphocytes

Hematopathology and Molecular Hematology
J S YangC D Platsoucas

Abstract

The human leukocyte-function-associated antigen-1 (LFA-1) plays a key role in intercellular adhesion interactions of the immune response. A monoclonal antibody (mab), designated LDA-8, is described that recognizes LFA-1. In contrast to nearly all other anti-LFA-1 mabs, which inhibit cellular aggregation, LDA-8 induces cell-cell aggregation. The LDA-8 mab was generated by immunizing mice with membrane fragments from the Jurkat T-cell line. The LDA-8 mab stained peripheral blood mononuclear cells (PBMC), monocyte-depleted peripheral blood lymphocytes, purified monocytes, and a number of T and B tumor cell lines. The LDA-8 mab induced aggregation of PBMC from normal donors, as well as of cells from T-cell lines (MOLT4 and CEM). Control mabs directed against HLA class 1 or CD4 did not induce aggregation. Aggregation was concentration- and time-dependent. EDTA added to the cultures 1 hour prior to or together with the LDA-8 mab did not inhibit LDA-8-induced aggregate formation. Anti LFA-1 alpha-chain mab added to the cells 1 hour prior to LDA-8 mab, or together with the LDA-8 mab, also did not inhibit LDA-8-induced aggregation. In contrast, anti-LFA-1 beta-chain mab, added to the cells together with or 1 hour prior to the LDA-8 mab,...Continue Reading