Endothelial cells exposed to anoxia/reoxygenation are hyperadhesive to T-lymphocytes: kinetics and molecular mechanisms.
OBJECTIVE
The objectives of this study were to 1) determine the time-course of T-lymphocyte adhesion to monolayers of human umbilical vein endothelial cell (HUVEC) that were exposed to 60 min of anoxia followed by 24 h of reoxygenation, and 2) define the mechanisms responsible for the hyperadhesivity of postanoxic HUVEC to human T-lymphocytes.


METHODS
Human peripheral blood mononuclear leukocytes were isolated from heparinized peripheral blood. T-lymphocytes were obtained by negative selection using a MACS column. HUVEC monolayers were exposed to anoxia/reoxygenation (A/R), and then reacted with 51Cr -labeled T-lymphocytes in adhesion assays.


RESULTS
A/R leads to an increased adhesion of T-lymphocytes to HUVEC monolayers, with peak responses occurring at 8 h after reoxygenation. This adhesion response was largely attributed to the CD4+ T-cell subset. The hyperadhesivity of A/R-exposed HUVEC was inhibited by monoclonal antibodies directed against either LFA-1, VLA-4, ICAM-1, or VCAM-1, indicating a contribution of these adhesion molecules and their ligands. Moreover, T-cell hyperadhesivity was attenuated by anti- IL-8. consistent with a role for this chemokine in the adhesion response. Protein synthesis inhibitors (actinomycin D and cycloheximide) as well as chemical inhibitors of (and binding ds-oligonucleotides to) NFkappaB and AP-1 significantly attenuated the A/R-induced T-lymphocyte adhesion responses. The kinetics of VCAM-1 on post-anoxic HUVEC correlated with the T-lymphocyte adhesion response.


CONCLUSIONS
A/R elicits a T-lymphocyte-endothelial cell adhesion response that involves transcription-dependent surface expression of VCAM-1.
Kokura
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Department of Molecular and Cellular Physiology, Louisiana State University Medical Center, Shreveport 71130-3932, USA.
Wolf
R E
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Yoshikawa
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T
Ichikawa
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H
Granger
D N
DN
Aw
T Y
TY
D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology; D001549:Benzamides / Q000494:pharmacology; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000502:physiology; D015687:Cell Hypoxia; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000502:physiology; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D016209:Interleukin-8 / Q000037:antagonists & inhibitors / Q000276:immunology / Q000502:physiology; D007511:Ischemia / Q000473:pathology*; D007700:Kinetics; D007976:Leupeptins / Q000494:pharmacology; D009097:Multienzyme Complexes / Q000502:physiology; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D010100:Oxygen / Q000494:pharmacology; D046988:Proteasome Endopeptidase Complex; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D015427:Reperfusion Injury / Q000473:pathology*; D016176:T-Lymphocyte Subsets / Q000166:cytology*; D013873:Thionucleotides / Q000494:pharmacology; D013997:Time Factors; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014471:Umbilical Veins; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000502:physiology
D000911:Antibodies, Monoclonal; D001549:Benzamides; D015815:Cell Adhesion Molecules; D016209:Interleukin-8; D007976:Leupeptins; D009097:Multienzyme Complexes; D016328:NF-kappa B; D011500:Protein Synthesis Inhibitors; D013873:Thionucleotides; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; C025160:3-aminobenzamide; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde; D010100:Oxygen