title: Identification of macrosialin (CD68) on the surface of host macrophages as the receptor for the intercellular adhesive molecule (ICAM-L) of Leishmania amazonensis.
abstract: The intercellular adhesive molecule, ICAM-L, of Leishmania amazonensis is known to block the attachment as well as internalisation of Leishmania for infection in host macrophages. We employed monoclonal antibodies (mAb) to the surface molecules of a macrophage to block the attachment of ICAM-L to the macrophage surface and identified that CD68 macrosialin is likely the receptor molecule on the macrophage for ICAM-L. We then demonstrated physical interaction between ICAM-L and macrosialin by co-immunoprecipitation of macrosialin with ICAM-L or vice versa. Finally, macrosialin is expressed in macrosialin-negative murine fibroblast cell line NCTC clone 2555 and demonstrates that both ICAM-L and promastigotes of L. amazonensis can bind to the CD68 transfectant. We thus conclude that CD68 macrosialin is the receptor on host macrophages for ICAM-L. Also, involvement of ICAM-L-macrosialin interaction in other Leishmania species and other mammalian macrophages were demonstrated, indicating the biological relevance of this ligand-receptor interaction.
authors.affiliation: Division of Infectious Disease and Immunology, Academia Sinica, (IMBS) No. 128, Academia Road Sec. 2, Nan-Kang, Taipei 11529, Taiwan, ROC.
authors.forename: Hang-Pong
authors.initials: HP
authors.lastname: Ng
authors.forename: Sui-Chi
authors.initials: SC
authors.lastname: Chiang
authors.forename: Yi
authors.initials: Y
authors.lastname: Chi
authors.forename: Sho-Tone
authors.initials: ST
authors.lastname: Lee
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D002448:Cell Adhesion / Q000502:physiology*; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D007891:Leishmania / Q000378:metabolism*; D008264:Macrophages / Q000737:chemistry* / Q000469:parasitology; D051379:Mice; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D015815:Cell Adhesion Molecules; C081026:CD68 protein, mouse; D000097382:CD68 Molecule