Induction, characterization, and functional coupling of the high affinity chemokine receptor for RANTES and macrophage inflammatory protein-1 alpha upon differentiation of an eosinophilic HL-60 cell line.
Eosinophilic differentiation of a pro-eosinophilic HL-60 cell line resulted in the induction of a high affinity RANTES/macrophage inflammatory protein-1 alpha receptor. The induced receptor is biochemically indistinguishable in RANTES equilibrium-binding studies from the monocytic receptor expressed on THP-1 cell membranes. Continued expression of the receptor requires the continuous presence of the inducing stimulus, and receptor site number declines without a loss of binding affinity with a t1/2 of 11.5 h on withdrawal of the inducing stimulus. The induced receptor is capable of three physiologic measures of receptor coupling, namely, ligand-induced Ca2+ fluxes, priming of the respiratory burst, and chemotaxis. Dose-dependent Ca2+ fluxes were elicited upon increasing concentrations of RANTES and MIP-1 alpha whereas no response was measured upon addition of MIP-1 beta or MCP-1. In addition, desensitization studies demonstrated that previous exposure to either RANTES or MIP-1 alpha almost completely inhibits a Ca2+ flux upon subsequent exposure to either ligand. Priming of the respiratory burst to PMA in differentiated cells by human rRANTES was more effective than priming by IL-5 or granulocyte-macrophage-CSF, whereas undifferentiated cells failed to secrete superoxide anion. In addition, differentiated cells underwent chemotaxis in response to RANTES. This provides the first evidence for the induction of a C-C chemokine receptor upon eosinophilic differentiation of a leukocyte cell line, and is in keeping with the demonstrated ability of human RANTES to induce the rapid formation of eosinophilic inflammatory sites.
Van Riper
G
G
Department of Biochemical and Molecular Pathology, Merck Research Laboratories, Rahway, NJ 07065.
Nicholson
D W
DW
Scheid
M P
MP
Fischer
P A
PA
Springer
M S
MS
Rosen
H
H
D002087:Butyrates / Q000494:pharmacology; D020148:Butyric Acid; D002118:Calcium / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D054407:Chemokine CCL4; D018946:Chemokine CCL5; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism*; D004804:Eosinophils / Q000166:cytology*; D006801:Humans; D066298:In Vitro Techniques; D008222:Lymphokines / Q000378:metabolism*; D046911:Macromolecular Substances; D019402:Macrophage Inflammatory Proteins; D015846:Monokines / Q000378:metabolism*; D019713:Receptors, CCR5; D019707:Receptors, Chemokine; D011971:Receptors, Immunologic / Q000502:physiology*; D016897:Respiratory Burst / Q000187:drug effects
D002087:Butyrates; D054407:Chemokine CCL4; D018946:Chemokine CCL5; D016207:Cytokines; D008222:Lymphokines; D046911:Macromolecular Substances; D019402:Macrophage Inflammatory Proteins; D015846:Monokines; D019713:Receptors, CCR5; D019707:Receptors, Chemokine; D011971:Receptors, Immunologic; C080633:macrophage inflammatory protein 1alpha receptor; D020148:Butyric Acid; D002118:Calcium