Effect of integrin beta 2 subunit truncations on LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) assembly, surface expression, and function.

Effect of Integrin b2 Subunit Truncations on LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) Assembly, Surface Expression, and Function

Competition between lymphocyte function-associated antigen 1 (CD11a/CD18) and Mac-1 (CD11b/CD18) for binding to intercellular adhesion molecule-1 (CD54).

Both human integrin receptors Mac-1 (CD11b/CD18,CR3)and lymphocyte function-associated antigen (LFA)-1 (CD11a/CD18) have been demonstrated to bind human intercellular adhesion molecule-1 (ICAM-1) (CD54). Here we show that LFA-1 and Mac-1 can bind to ICAM-1 in the mouse as well. Interestingly, we observed that binding of murine LFA-1 dominates over Mac-1 for binding to ICAM-1. Using three differ...

Monomeric expression of bovine beta2-integrin subunits reveals their role in Mannheimia haemolytica leukotoxin-induced biological effects.

The ruminant-specific leukotoxin (Lkt) of Mannheimia haemolytica is the key virulence factor contributing to the pathogenesis of lung injury in bovine pneumonic pasteurellosis. Previous studies by us and others indicate that M. haemolytica Lkt binds to CD18, the beta subunit of bovine beta(2)-integrins on leukocytes, and that the species specificity of Lkt-induced effects is resident in the bet...

Aggravated Lyme carditis in CD11a-/- and CD11c-/- mice.

CD18 hypomorph mice expressing reduced levels of the common beta2 integrin chain develop aggravated Lyme carditis, compared to that developed by wild-type (WT) mice, upon infection with the spirochete Borrelia burgdorferi. The enhancement of Lyme carditis in these mice is characterized by increased macrophage infiltration, correlating with augmented expression of the monocyte/macrophage chemoat...

beta(2) integrin Mac-1 is a receptor for Mannheimia haemolytica leukotoxin on bovine and ovine leukocytes.

Pneumonia caused by Mannheimia haemolytica is an important disease of cattle (BO), domestic sheep (DS, Ovis aries) and bighorn sheep (BHS, Ovis canadensis). Leukotoxin (Lkt) produced by M. haemolytica is cytolytic to all leukocyte subsets of these three species. Although it is certain that CD18, the beta subunit of beta(2) integrins, mediates Lkt-induced cytolysis of leukocytes, whether CD18 of...