Protein Kinase CK2 Regulates Leukocyte-Endothelial Cell Interactions during Ischemia and Reperfusion in Striated Skin Muscle.
BACKGROUND
Ischemia and reperfusion (I/R) causes tissue injury by inflammatory processes. This involves the upregulation of endothelial surface proteins by phospho-regulated signaling pathways, resulting in enhanced interactions of leukocytes with endothelial cells. Recently, we found that protein kinase CK2 is a crucial regulator of leukocyte-mediated inflammation. Therefore, in this study we investigated the involvement of CK2 in leukocyte-endothelial cell interactions during I/R injury.


METHODS
We first analyzed the inhibitory action of (E)-3-(2,3,4,5-tetrabromophenyl)acrylic acid (TBCA) and CX-4945 on CK2 kinase activity and the viability of human dermal microvascular endothelial cells (HDMEC). To mimic I/R conditions in vitro, HDMEC were exposed to hypoxia and reoxygenation and the expression of adhesion molecules was analyzed by flow cytometry. Moreover, we analyzed in vivo the effect of CK2 inhibition on leukocyte-endothelial cell interactions in the dorsal skinfold chamber model of I/R injury by means of repetitive intravital fluorescence microscopy and immunohistochemistry.


RESULTS
We found that TBCA and CX-4945 suppressed the activity of CK2 in HDMEC without affecting cell viability. This was associated with a significant downregulation of E-selectin and intercellular adhesion molecule (ICAM)-1 after in vitro hypoxia and reoxygenation. In vivo, CX-4945 treatment significantly decreased the numbers of adherent and transmigrated leukocytes in striated muscle tissue exposed to I/R.


CONCLUSIONS
Our findings indicate that CK2 is involved in the regulation of leukocyte-endothelial cell interactions during I/R by mediating the expression of E-selectin and ICAM-1.
Institute for Clinical and Experimental Surgery, Saarland University, Homburg/Saar, Germany.
Emmanuel
E
Ampofo
Daniela
D
Widmaier
Mathias
M
Montenarh
Michael D
MD
Menger
Matthias W
MW
Laschke
D000818:Animals; D047390:Casein Kinase II / Q000037:antagonists & inhibitors / Q000502:physiology*; D002450:Cell Communication; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000502:physiology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D007962:Leukocytes / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009287:Naphthyridines / Q000494:pharmacology; D010619:Phenazines; D015427:Reperfusion Injury / Q000209:etiology*; D012867:Skin / Q000098:blood supply*
D009287:Naphthyridines; D010619:Phenazines; D018799:Intercellular Adhesion Molecule-1; C555142:silmitasertib; D047390:Casein Kinase II