Pathways involved in the synergistic activation of macrophages by lipoteichoic acid and hemoglobin.

Lipoteichoic acid (LTA) is a Gram-positive cell surface molecule that is found in both a cell-bound form and cell-free form in the host during an infection. Hemoglobin (Hb) can synergize with LTA, a TLR2 ligand, to potently activate macrophage innate immune responses in a TLR2- and TLR4-dependent way. At low levels of LTA, the presence of Hb can result in a 200-fold increase in the secretion of IL-6 following macrophage activation.

Directed evaluation of enterotoxigenic Escherichia coli autotransporter proteins as putative vaccine candidates.

Background: Enterotoxigenic Escherichia coli (ETEC) is a major diarrheal pathogen in developing countries, where it accounts for millions of infections and hundreds of thousands of deaths annually. While vaccine development to prevent diarrheal illness due to ETEC is feasible, extensive effort is needed to identify conserved antigenic targets. Pathogenic Escherichia coli, including ETEC, use the autotransporter (AT) secretion mechanism to export virulence factors.

Peptides derived from platelet non-integrin collagen-receptors or types I and III collagen inhibit collagen-platelet interaction.

Platelet-collagen interaction plays an important role in hemostasis and pathological thrombosis. Upon an injury to the subendothelium of a blood vessel wall, platelets adhere to the denuded substrate, aggregate, and release biological substances. Many investigators have explored the use of blocking agents to interrupt the final step of binding fibrinogen on glycoprotein (GP) IIb/IIIa of activated platelets.

Type I and type III collagen-platelet interaction: inhibition by type specific receptor peptides.

We have previously cloned and characterized a platelet receptor for type III collagen (47 kDa) from a human bone marrow cDNA phage library and defined two active peptides. We also cloned and characterized a platelet receptor for type I collagen (65 kDa) and defined an active peptide. Our objective was to study whether there is type specificity of these active peptides.

Role of platelet endothelial form of nitric oxide synthase in collagen-platelet interaction: regulation by phosphorylation.

Different pathways have been reported to be involved in platelet-collagen interaction. We have reported that the platelet endothelial form of nitric oxide synthase (eNOS) and the platelet receptor for type I collagen, p65, are closely associated. But the controlling mechanism underlying the generation of nitric oxide (NO) by the eNOS has not been fully explored.

Cloning, characterization, and functional studies of a 47-kDa platelet receptor for type III collagen.

A 1.2-kb cDNA fragment encoding a platelet 47-kDa protein has been isolated from a human bone marrow cDNA library by using a degenerate oligonucleotide of the sequenced amino terminus of the purified platelet protein with a poly(dT)(12).(dG) by polymerase chain reaction.