title: Shockwaves increase T-cell proliferation and IL-2 expression through ATP release, P2X7 receptors, and FAK activation.
abstract: Shockwaves elicited by transient pressure disturbances are used to treat musculoskeletal disorders. Previous research has shown that shockwave treatment affects T-cell function, enhancing T-cell proliferation and IL-2 expression by activating p38 mitogen-activated protein kinase (MAPK) signaling. Here we investigated the signaling pathway by which shockwaves mediate p38 MAPK phosphorylation. We found that shockwaves at an intensity of 0.18 mJ/mm(2) induce the release of extracellular ATP from human Jurkat T-cells at least in part by affecting cell viability. ATP released into the extracellular space stimulates P2X7-type purinergic receptors that induce the activation of p38 MAPK and of focal adhesion kinase (FAK) by phosphorylation on residues Tyr397 and Tyr576/577. Elimination of released ATP with apyrase or inhibition of P2X7 receptors with the antagonists KN-62 or suramin significantly weakens FAK phosphorylation, p38 MAPK activation, IL-2 expression, and T-cell proliferation. Conversely, addition of exogenous ATP causes phosphorylation of FAK and p38 MAPK. Silencing of FAK expression also reduces these cell responses to shockwave treatment. We conclude that shockwaves enhance p38 MAPK activation, IL-2 expression, and T-cell proliferation via the release of cellular ATP and feedback mechanisms that involve P2X7 receptor activation and FAK phosphorylation.
authors.affiliation: Dept. of Orthopedics, First Hospital of Jilin Univ., Changchun 130021, China. tiechengyu@163.com
authors.forename: Tiecheng
authors.initials: T
authors.lastname: Yu
authors.forename: Wolfgang G
authors.initials: WG
authors.lastname: Junger
authors.forename: Changji
authors.initials: C
authors.lastname: Yuan
authors.forename: An
authors.initials: A
authors.lastname: Jin
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhao
authors.forename: Xueqing
authors.initials: X
authors.lastname: Zheng
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zeng
authors.forename: Jianguo
authors.initials: J
authors.lastname: Liu
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000031:analogs & derivatives / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000378:metabolism*; D001081:Apyrase / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects*; D002470:Cell Survival; D004789:Enzyme Activation; D051417:Focal Adhesion Kinase 1 / Q000235:genetics / Q000378:metabolism*; D019220:High-Energy Shock Waves; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism*; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000528:radiation effects; D010766:Phosphorylation; D058919:Purinergic P2 Receptor Antagonists; D034622:RNA Interference; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D058486:Receptors, Purinergic P2X7; D015398:Signal Transduction / Q000187:drug effects / Q000528:radiation effects*; D013498:Suramin / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects / Q000201:enzymology / Q000276:immunology / Q000528:radiation effects*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: C508594:IL2 protein, human; D007376:Interleukin-2; C546468:P2RX7 protein, human; D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2; D058486:Receptors, Purinergic P2X7; D013498:Suramin; C063302:KN 62; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000255:Adenosine Triphosphate; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D048051:p38 Mitogen-Activated Protein Kinases; D001081:Apyrase