Expression and function of intercellular adhesion molecule 1 (ICAM-1) on rat thymic macrophages in culture.
The expression of intercellular adhesion molecule 1 (ICAM-1) was studied on freshly isolated rat thymic macrophages (TMF) and after their cultivation in serum-free medium using monoclonal antibody (mAb) 1A 29 and a streptavidin-biotin immunoperoxidase technique. ICAM-1 was expressed on about 80% of freshly isolated TMF. Upon cultivation, the percentage of ICAM-1+ TMF decreased to about 30-40% in 12-day-old culture. Using double immunofluorescence staining it was found that ICAM-1 was expressed both on cortical (R-MC 40+) and CMZ/medullary (R-MC 43+) macrophage subsets. ICAM-1 was up-regulated on TMF in culture by recombinant IFN-gamma, IL1 and TNF-alpha and was down-regulated by dexamethasone. Syngeneic thymocytes bound to cultivated TMF in a rosette form at both 37 degrees C and 4 degrees C. IFN-gamma treatment did not increase the binding formation. The binding between thymocytes and IFN-gamma-stimulated TMF at 37 degrees C was inhibited by pretreatment of TMF with anti-ICAM-1 mAb or pretreatment of thymocytes with anti-LFA-1 mAb, indicating that ICAM-1 on TMF is one of the ligands involved in TMF/thymocyte adhesion and subsequent direct cell-cell communication.
Colić
M
M
Institute of Medical Research, Military Medical Academy, Belgrade, Yugoslavia.
Drabek
D
D
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000378:metabolism*; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D007124:Immunoenzyme Techniques; D008264:Macrophages / Q000276:immunology / Q000378:metabolism*; D008297:Male; D051381:Rats; D012397:Rosette Formation; D013950:Thymus Gland / Q000276:immunology / Q000378:metabolism
D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules; D016207:Cytokines