title: Anti-CD14 Antibody-treated Neutrophils Respond to LPS: Possible Involvement of CD14 Upregulated by Anti-CD14 Antibody Binding.
abstract: CD14 and Toll-like receptor 4/MD2 (TLR4/MD2) mediate the action of LPS on neutrophils. The anti-CD14 antibody and the TLR4/MD2-antagonist, synthetic lipid IVa (LA-14-PP), are known to inhibit the response of neutrophils to LPS. We studied the role of CD14 in LPS-induced priming of neutrophils for enhanced release of the superoxide anion. The anti-CD14 antibody at much higher concentrations than required to saturate CD14 was required to inhibit priming by LPS. The inhibitory effect of the anti-CD14 antibody was overcome by LPS. After washing, anti-CD14-treated neutrophils showed upregulated CD14 upon incubation at 37°C and responded to LPS with a delayed time-course. Thus, CD14-blocked neutrophils gained responsiveness to LPS through newly upregulated CD14. These results suggested that the unbound/free anti-CD14 antibody was essential to inhibit LPS-induced priming by blocking CD14 that were newly expressed during incubation at 37°C. LA-14-PP inhibited the response of neutrophils to LPS in an anti-CD14 antibody sensitive manner. When neutrophils were treated with LA-14-PP followed by treatment with the anti-CD14 antibody, CD14 was upregulated upon warming, but priming was blocked, suggesting that TLR4/MD2 was not newly expressed by warming in association with CD14 molecules. Thus, in addition to blocking CD14, the anti-CD14 antibody was found to induce the expression of new CD14.
authors.affiliation: a Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science , Kyushu University , Fukuoka , Japan.
authors.forename: Terukazu
authors.initials: T
authors.lastname: Sanui
authors.affiliation: a Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science , Kyushu University , Fukuoka , Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Takeshita
authors.affiliation: a Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science , Kyushu University , Fukuoka , Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Fukuda
authors.affiliation: b Division of General Dentistry, Faculty of Dental Science , Kyushu University , Fukuoka , Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Haraguchi
authors.affiliation: a Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science , Kyushu University , Fukuoka , Japan.
authors.forename: Yoshitomi
authors.initials: Y
authors.lastname: Aida
authors.affiliation: a Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science , Kyushu University , Fukuoka , Japan.
authors.forename: Fusanori
authors.initials: F
authors.lastname: Nishimura
mesh_terms: D000906:Antibodies / Q000378:metabolism*; D000937:Antigen-Antibody Reactions; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D006017:Glycolipids / Q000494:pharmacology; D006801:Humans; D008050:Lipid A / Q000031:analogs & derivatives / Q000494:pharmacology; D018950:Lipopolysaccharide Receptors / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000276:immunology; D018375:Neutrophil Activation / Q000187:drug effects; D009504:Neutrophils / Q000276:immunology*; D011485:Protein Binding; D015398:Signal Transduction; D013481:Superoxides / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000037:antagonists & inhibitors*; D015854:Up-Regulation
chemical_list: D000906:Antibodies; D006017:Glycolipids; D008050:Lipid A; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; C040142:lipid A precursors, bacterial; D013481:Superoxides
keywords: Anti-CD14 antibody; LPS; neutrophil; priming; superoxide