Lymphotoxin (LT) is a cytokine related to TNF, found in human systems in both secreted and membrane bound forms. The well characterized secreted form is a trimer of a single protein, LT-alpha, whereas the surface form is composed of a complex between two related molecules, LT-alpha and LT-beta. Because there is a distinct receptor for the complex, the membrane form is believed to signal via events different from those elicited by TNF and secreted LT-alpha.
View Article and Find Full Text PDFObjective: The authors sought to determine whether the signs and symptoms of endotoxemia were related to the endotoxin-stimulated increase in circulating phospholipase A2 (PLA2) activity.
Background: Because hypotension and pulmonary injury have been associated with elevated PLA2 activity in septic shock and PLA2 levels are reduced with the administration of glucocorticoids, the PLA2 response to endotoxin was investigated in volunteers pretreated with and without hydrocortisone.
Methods: Carefully screened human subjects were studied under four conditions: (1) saline, (2) hydrocortisone, (3) endotoxin, and (4) hydrocortisone administration before endotoxin exposure.
Interaction of the vascular cell adhesion molecule (VCAM-1) with its counter-receptor very late antigen-4 (VLA-4) (integrin alpha 4 beta 1) is important for a number of developmental pathways and inflammatory functions. We are investigating the molecular mechanism of this binding, in the interest of developing new anti-inflammatory drugs that block it. In a previous report, we showed that the predominant form of VCAM-1 on stimulated endothelial cells, seven-domain VCAM (VCAM-7D), is a functionally bivalent molecule.
View Article and Find Full Text PDFBiochem Biophys Res Commun
August 1991
Vascular cell adhesion molecule 1 (VCAM1) is a leukocyte adhesion molecule induced on human endothelium in vitro and in vivo by inflammatory stimuli. A truncated cDNA for VCAM1 was constructed, stably expressed in Chinese Hamster Ovary (CHO) cells, and the secreted recombinant soluble form of VCAM1 (rsVCAM1) purified to homogeneity by immunoaffinity chromatography. Immobilized rsVCAM1 is a functional adhesion protein, and selectively binds only VLA4-expressing cells, including human B and T lymphocytes, NK cells, and certain lymphoblastoid cell lines.
View Article and Find Full Text PDFEndothelial leukocyte adhesion molecule 1 (ELAM1) is a leukocyte adhesion molecule induced on human venular endothelium in vitro and in vivo by inflammatory stimuli. A truncated cDNA for ELAM1 has been constructed, stably expressed in Chinese hamster ovary cells, and the secreted recombinant soluble form of ELAM1 (rsELAM1) purified to homogeneity by immunoaffinity chromatography. rsELAM1, when immobilized on plastic, is fully functional as an adhesion protein, and selectively binds only cells known to bind cell-surface ELAM1 expressed on human endothelial cells, including the myelomonocytic cell line HL60 and the colon carcinoma cell line HT29.
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