Adhesion properties of Mono Mac 6, a monocytic cell line with characteristics of mature human monocytes.
Progress in the understanding of blood cell--endothelial cell interactions has been achieved by the development of in-vitro model systems. We describe adhesion properties of the recently established human monocytic cell line Mono Mac 6. These cells showed increased adherence to unstimulated and tumour necrosis factor (TNF)-alpha (50 U/ml) stimulated human umbilical vein endothelial cells (HUVEC) (9.4% +/- 0.4% and 56.5% +/- 3.3%), as compared to U937 cells (2.6% +/- 0.8% and 40.0% +/- 8.4%). The values were similar to freshly isolated human blood monocytes (18.8% +/- 7.5% and 55.7% +/- 9.3%, respectively). Maximal binding was 6.2 +/- 0.6 Mono Mac 6 cells per HUVEC, which was 34% less than U937 cells (8.9 +/- 0.3). The lower number of adherent Mono Mac 6 cells per HUVEC could be due to their larger size, as assessed by flow cytometry. Blocking experiments with monoclonal antibody (mAb) directed against E-selectin, VCAM-1 and ICAM-1 on HUVEC and CD11b or CD14 on Mono Mac 6 cells demonstrated the contribution of these molecules to Mono Mac 6 adherence. Reduced binding after 24 h parallels the decline of E-selectin expression in HUVEC. Linearity of cell binding was confirmed from 0.2 x 10(6) to 1.0 x 10(6) Mono Mac 6 cells. Expression of CD11b and CD14 in Mono Mac 6 cells and in isolated human monocytes but not in U937 cells leading to interaction with ICAM-1 on HUVEC appears to be responsible for the increased adhesion of Mono Mac 6, as compared to U937 cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Erl
W
W
Institut für Prophylaxe und Epidemiologie der Kreislaufkrankheiten, Universität München, Germany.
Weber
C
C
Wardemann
C
C
Weber
P C
PC
D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002460:Cell Line; D048429:Cell Size; D019040:E-Selectin; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D018950:Lipopolysaccharide Receptors; D016177:Macrophage-1 Antigen / Q000378:metabolism; D009000:Monocytes / Q000166:cytology* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D019010:Vascular Cell Adhesion Molecule-1
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D015815:Cell Adhesion Molecules; D019040:E-Selectin; D018950:Lipopolysaccharide Receptors; D016177:Macrophage-1 Antigen; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1