Human phagocytes have multiple lipid A-binding sites

D T Golenbock, R Y Hampton, C R Raetz, S D Wright
1990 Infection and Immunity  
Bacterial lipopolysaccharide (LPS) is a potent stimulus of cells, yet a target protein for LPS has not been defined. We used two approaches to define LPS-binding sites on cell surfaces: one assay measured binding of LPS-coated erythrocytes (ELPS) to cultured human cells, and a second measured binding of a radiolabeled probe, [32P]lipid IVA, to intact leukocytes. The first approach identified the CD11-CD18 family of integrins as lipid A-binding sites in human phagocytes, and the latter approach
more » ... he latter approach demonstrated saturable lipid A binding to intact murine macrophages, as well as to an approximately 95-kDa binding protein in purified membrane preparations. Because CD18 has a known molecular mass of 95 kDa, we sought to determine whether the * Corresponding author. t Present address: Maxwell Finland Laboratory for Infectious Diseases, 774 Albany St., Boston, MA 02118. MATERIALS AND METHODS Reagents. Hams F-12 and RPMI 1640 medium were purchased from M.A. Bioproducts (Walkersville, Md.) or GIBCO (Chagrin Falls, Ohio), and fetal bovine serum (LPS, 4069
doi:10.1128/iai.58.12.4069-4075.1990 fatcat:hm3zcoattbd6lg6ibwskgvo42y