TY - JOUR
T1 - HMGB1 binds to activated platelets via the receptor for advanced glycation end products and is present in platelet rich human coronary artery thrombi
AU - Ahrens, Ingo
AU - Chen, Yung-Chih
AU - Topcic, Danijal
AU - Bode, Michael
AU - Haenel, David
AU - Hagemeyer, Christoph Eugen
AU - Seeba, Hannah
AU - Duerschmied, Daniel
AU - Bassler, Nicole
AU - Jandeleit-Dahm, Karin
AU - Sweet, Matthew James
AU - Agrotis, Alexander
AU - Bobik, Alexander
AU - Peter, Karlheinz
PY - 2015
Y1 - 2015
N2 - High mobility group box 1 (HMGB1) acts as both a nuclear protein that regulates gene expression, as well as a pro-inflammatory alarmin that is released from necrotic or activated cells. Recently, HMGB1-expression in human atherosclerotic plaques was identified. Therapeutic blockade of HMGB1 reduced the development of diet-induced atherosclerosis in ApoE knockout mice. Thus, we hypothesised an interaction between HMGB1 and activated platelets. Binding of recombinant HMGB1 to platelets was assessed by flow cytometry. HMGB1 bound to thrombin-activated human platelets (MFI 2.49 vs 25.01, p=0.0079). Blood from wild-type, TLR4 and RAGE knockout mice was used to determine potential HMGB1 receptors on platelets. HMGB1 bound to platelets from wild type C57Bl6 (MFI 2.64 vs 20.3, p<0.05), and TLR4-/- mice (MFI 2.11 vs 25.65, p<0.05) but failed to show binding to platelets from RAGE-/- mice (p > 0.05). RAGE expression on human platelets was detected by RT-PCR with mRNA extracted from highly purified platelets and confirmed by Western blot and immunofluorescence microscopy. Platelet activation increased RAGE surface expression (MFI 4.85 vs 6.74, p<0.05). Expression of HMGB1 in human coronary artery thrombi was demonstrated by immunohistochemistry and revealed high expression levels. Platelets bind HMGB1 upon thrombin-induced activation. Platelet specific expression of RAGE could be detected at the mRNA and protein level and is involved in the binding of HMGB1. Furthermore, platelet activation up-regulates platelet surface expression of RAGE. HMGB1 is highly expressed in platelet- rich human coronary artery thrombi pointing towards a central role for HMGB1 in atherothrombosis, thereby suggesting the possibility of platelet targeted anti-inflammatory therapies for atherothrombosis.
AB - High mobility group box 1 (HMGB1) acts as both a nuclear protein that regulates gene expression, as well as a pro-inflammatory alarmin that is released from necrotic or activated cells. Recently, HMGB1-expression in human atherosclerotic plaques was identified. Therapeutic blockade of HMGB1 reduced the development of diet-induced atherosclerosis in ApoE knockout mice. Thus, we hypothesised an interaction between HMGB1 and activated platelets. Binding of recombinant HMGB1 to platelets was assessed by flow cytometry. HMGB1 bound to thrombin-activated human platelets (MFI 2.49 vs 25.01, p=0.0079). Blood from wild-type, TLR4 and RAGE knockout mice was used to determine potential HMGB1 receptors on platelets. HMGB1 bound to platelets from wild type C57Bl6 (MFI 2.64 vs 20.3, p<0.05), and TLR4-/- mice (MFI 2.11 vs 25.65, p<0.05) but failed to show binding to platelets from RAGE-/- mice (p > 0.05). RAGE expression on human platelets was detected by RT-PCR with mRNA extracted from highly purified platelets and confirmed by Western blot and immunofluorescence microscopy. Platelet activation increased RAGE surface expression (MFI 4.85 vs 6.74, p<0.05). Expression of HMGB1 in human coronary artery thrombi was demonstrated by immunohistochemistry and revealed high expression levels. Platelets bind HMGB1 upon thrombin-induced activation. Platelet specific expression of RAGE could be detected at the mRNA and protein level and is involved in the binding of HMGB1. Furthermore, platelet activation up-regulates platelet surface expression of RAGE. HMGB1 is highly expressed in platelet- rich human coronary artery thrombi pointing towards a central role for HMGB1 in atherothrombosis, thereby suggesting the possibility of platelet targeted anti-inflammatory therapies for atherothrombosis.
UR - http://th.schattauer.de/en/contents/archive/issue/2275/manuscript/24638.html
U2 - 10.1160/TH14-12-1073
DO - 10.1160/TH14-12-1073
M3 - Article
VL - 114
SP - 994
EP - 1003
JO - Thrombosis and Haemostasis
JF - Thrombosis and Haemostasis
SN - 0340-6245
IS - 5
ER -