CD45RA-RO+ (memory) but not CD45RA+RO- (naive) T cells roll efficiently on E- and P-selectin and vascular cell adhesion molecule-1 under flow.

This study examines the molecular mechanisms that underlie the observed preferential interactions of memory vs naive T cells with activated vascular endothelium. Many more CD4+ CD45RO+ (memory) cells adhered to 6-h TNF-alpha-activated human umbilical vein endothelium under flow than CD4+CD45RA+ (naive) cells. Adhesion studies were performed using Chinese hamster ovary (CHO) cell monolayers expressing human E- or P-selectin (CHO-E and CHO-P, respectively) or with soluble vascular cell adhesion molecule-1 (VCAM-1)-coated glass surfaces.

A human colon carcinoma cell line exhibits adhesive interactions with P-selectin under fluid flow via a PSGL-1-independent mechanism.

It has been postulated that endothelial cell adhesion molecules involved in leukocyte recruitment play a role in metastasis. Using an in vitro flow model, we studied the adhesion of the human colon carcinoma cell line KM12-L4 to P-selectin, an inducible endothelial-expressed adhesion molecule involved in leukocyte recruitment. Recombinant forms of P-selectin and Chinese hamster ovary cells stably expressing P-selectin supported attachment and rolling of KM12-L4 cells at 1 to 2 dynes/cm2.

P-selectin glycoprotein ligand-1 is the major counter-receptor for P-selectin on stimulated T cells and is widely distributed in non-functional form on many lymphocytic cells.

P-selectin glycoprotein ligand-1 (PSGL-1) is the high affinity counter-receptor for P-selectin on myeloid cells (Sako, D., Chang, X.J.

Expression cloning of a functional glycoprotein ligand for P-selectin.

The initial adhesive interactions between circulating leukocytes and endothelia are mediated, in part, by P-selectin. We now report the expression cloning of a functional ligand for P-selectin from an HL-60 cDNA library. The predicted amino acid sequence reveals a novel mucin-like transmembrane protein.

Antiinflammatory properties of hepatic acute phase proteins: preferential induction of interleukin 1 (IL-1) receptor antagonist over IL-1 beta synthesis by human peripheral blood mononuclear cells.

This study was undertaken to determine whether acute phase proteins (APP) induce the synthesis of interleukin 1 beta (IL-1 beta) and its specific antagonist, IL-1 receptor antagonist (IL-1Ra), in human peripheral blood mononuclear cells (PBMC). PBMC from healthy volunteers were incubated with C-reactive protein (CRP), alpha 1-antitrypsin (alpha 1-AT), or alpha 1-acid glycoprotein (AGP), and the levels of IL-1 beta and IL-1Ra produced were measured by specific radioimmunoassay. To evaluate the effects of alpha 1-AT further, a synthetic pentapeptide FVYLI corresponding to the minimal binding sequence for the serpine-enzyme complex receptor was also evaluated.