Abstract
E-selectin and β2 integrin (CD18) mediate leukocyte rolling and firm adhesion, respectively. The objective of this study was to examine the cooperative functions of CD18 and E-selectin in leukocyte rolling and firm adhesion using intravital microscopy of the TNF-α-treated cremaster muscle. Compared to wild type mice (WT), leukocyte rolling velocities in CD18 null mice (CD 18-/-) were significantly increased (from 7 to 23 μm/s) and further increased by E-selectin blockade with mAb 9A9 (to 39 μm/s). As a consequence of the reduced transit times through observed venules, leukocyte adhesion efficiency in the absence of CD18 decreased (from 76 adherent cells per 100 rolling cells/min in WT, to 22 in CD18-/-, and to 5 in CD18-/- with mAb 9A9). The number of adherent and transmigrated neutrophils was not altered in CD18-/- mice or in WT mice treated with E-selectin mAb, but significantly reduced (by 47%) in the absence of both CD18 and E-selectin function. In these mice, only 65% of transmigrated leukocytes were neutrophils, compared to 81-91% in all other groups. Therefore, we conclude that E-selectin becomes essential for neutrophil recruitment when CD18 is not available.
Original language | English (US) |
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Pages (from-to) | A776 |
Journal | FASEB Journal |
Volume | 12 |
Issue number | 5 |
State | Published - Mar 20 1998 |
Externally published | Yes |
ASJC Scopus subject areas
- Biotechnology
- Biochemistry
- Molecular Biology
- Genetics