title: Tumor necrosis factor-α pathway plays a critical role in regulating interferon-γ induced protein-10 production in initial allogeneic human monocyte-endothelial cell interactions.
abstract: T-cell infiltration of allografts is a major pathologic component defining acute rejection episodes (ARE). We have shown that monocytes interact with allogeneic endothelial cells (ECs) for costimulation to achieve T-cell allorecognition. However, the production of T-cell interferon-γ induced protein-10 (IP-10) and regulation of this chemokine during the initial monocyte-EC interaction are unclear. We hypothesized that the tumor necrosis factor (TNF)-α pathway plays a key role to regulate IP-10 production during the initial monocyte-EC interaction. Cytokine-activated ECs were analyzed for IP-10 production and adhesion molecule expression. Established, monocyte-EC cocultures were analyzed using real-time polymerase chain reaction and a chemokine assay for IP-10 and activation factors. Anti-TNF-α antibody was used to neutralize TNF-α release during monocyte-EC interactions. TNF-α-activated ECs upregulated CD62E and CD54 as determined by flow cytometry, releasing high levels of IP-10 and interleukin (IL)-6. Interferon-γ-stimulated ECs also produced high levels of IP-10 and IL-6. Monocyte-EC interactions demonstrated upregulation of gene transcripts for TNF-α, IL-6, and IP-10. The cytokine/chemokine assay detected high levels of TNF-α, IL-6, and IP-10 in coculture supernates in a time-dependent manner. Anti-TNF-α antibody dramatically reduced IP-10 production by monocyte-ECs interactions. However, anti-TNF-α antibody did not prevent the release of IL-6 by monocytes in EC cocultures. Our results showed that ECs activated by TNF-α are an important source of IP-10. The monocyte-EC interaction produces high levels of IP-10. The TNF-α pathway plays a key role to regulate IP-10 production during monocyte-EC interactions. We thus proposed that the initial monocyte-EC interaction with increased expression of IP-10 may play a critical role to initiate and augment T-cell-mediated ARE.
authors.affiliation: Department of Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, P.R. China.
authors.forename: Y S
authors.initials: YS
authors.lastname: Fang
authors.forename: L M
authors.initials: LM
authors.lastname: Zhu
authors.forename: Z G
authors.initials: ZG
authors.lastname: Sun
authors.forename: L Z
authors.initials: LZ
authors.lastname: Yu
authors.forename: H
authors.initials: H
authors.lastname: Xu
mesh_terms: D057134:Antibodies, Neutralizing; D002450:Cell Communication; D002478:Cells, Cultured; D054357:Chemokine CXCL10 / Q000235:genetics / Q000378:metabolism*; D018920:Coculture Techniques; D019040:E-Selectin / Q000378:metabolism; D042783:Endothelial Cells / Q000276:immunology*; D005434:Flow Cytometry; D006084:Graft Rejection / Q000276:immunology; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D009000:Monocytes / Q000276:immunology*; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology / Q000378:metabolism*
chemical_list: D057134:Antibodies, Neutralizing; C114753:CXCL10 protein, human; D054357:Chemokine CXCL10; D019040:E-Selectin; C508600:IL6 protein, human; D015850:Interleukin-6; D012333:RNA, Messenger; C546936:SELE protein, human; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1