Recently, we have demonstrated that antibodies that block the function of the b2-integrin leukocyte function-associated antigen-1 (LFA-1) completely abrogate the rapid mobilization of hematopoietic progenitor cells (HPC) with colonyforming and radioprotective capacity induced by interleukin-8 (IL-8) in mice. These findings suggested a direct inhibitory effect of these antibodies on LFA-1–mediat...

Firm adhesion of rolling neutrophils on inflamed endothelium is dependent on beta(2) (CD18)-integrins and activating stimuli. LFA-1 (CD11a/CD18) appears to be more important than Mac-1 (CD11b/CD18) in neutrophil emigration at inflammatory sites, but little is known of the relative binding characteristics of these two integrins under conditions thought to regulate firm adhesion. The present stud...

LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) are members of the beta2 integrins involved in leukocyte function during immune and inflammatory responses. We aimed to determine a minimized beta2 subunit that forms functional LFA-1 and Mac-1. Using a series of truncated beta2 variants, we showed that the subregion Q23-D300 of the beta2 subunit is sufficient to combine with the alphaL and alphaM subun...

We sought additional evidence for an inverse relationship between functional CTL-target cell affinity on the one hand, and susceptibility of the CTL-mediated killing to inhibition by alpha LFA-1 and alpha Lyt-2,3 monoclonal antibodies on the other hand. Previously, we experimentally reduced affinity by pretreating the target cells with papain. This removed most of the class I H-2 antigens, had ...

for the scientific and accurate management of rangeland ecosystems, having information about ecosystem as indicators of ecosystem health and function is needed. the aim of this research is to study the effects of grazing on soil surface indicators and rangeland functional properties by using landscape functional analysis (lfa) method. for this purpose, the present study was conducted in two reg...

The leukocyte function-associated antigen 1 (LFA-1) molecule is well established as a surface protein involved in cellular adhesion and interaction, but there has been little information about whether engagement of this molecule can also directly modify cellular activation. These studies demonstrate that crosslinking the LFA-1 molecule on human T cell clones transmits a unique signal to the cel...

Pertussis toxin (PT) inhibits invasiveness of T-cell hybridomas in vitro and metastasis formation in vivo. We present evidence for the hypothesis that PT interferes with functional activation of LFA-1. Invasion by TAM2D2 T-cell hybridoma cells of fibroblast monolayers was completely blocked by PT pretreatment, but the cells regained invasiveness in the presence of Mn2+, which activates LFA-1. T...

In order to evaluate the functions of lymphocyte function antigen-1 (LFA-1) (CD11a/CD18) and Mac-1 (CD11b/CD18) on neonatal neutrophils, we examined neutrophil adhesion to and migration through human umbilical vein endothelial cell (HUVEC) monolayers in vitro. Transendothelial migration of adult neutrophils was greatly enhanced by preincubation of HUVEC with interleukin-1 (IL-1). This migration...

Shedding of adhesion molecules has been described for members of the selectin and immunoglobulin superfamilies, but integrins are not known to be shed. Here, we describe shedding of the integrin lymphocyte function-associated antigen-1 (LFA-1; CD11a/CD18) from human leukocytes during the cutaneous inflammatory response to the blistering agent cantharidin. Expression of LFA-1 was significantly d...

Lymphocyte function-associated antigen 1/intercellular adhesion molecule 1 (LFA-1/ICAM-1)-and very late antigen 4/vascular cell adhesion molecule 1 (VLA-4/VCAM-1)-mediated adhesion of T lymphocytes to endothelial cells (EC) can be regulated by increased expression of ICAM-1 and VCAM-1 upon cytokine treatment of EC, or by activation of the integrin molecules LFA-1 and VLA-4 on T cells. Here, we ...