Thromb Haemost 2003; 90(04): 724-733
DOI: 10.1160/TH03-04-0291
Cellular Proteolysis and Oncology
Schattauer GmbH

Plasmin generation dependent on α-enolase-type plasminogen receptor is required for myogenesis

Roser López-Alemany
1   Institut de Recerca Oncològica (IRO), Centre d’Oncología Molecular, L’Hospitalet de Llobregat, Barcelona, Spain
,
Mònica Suelves
2   Centre de Regulació Genòmica (CRG), Programa de Diferenciació i Cancer, Barcelona, Spain
,
Pura Muñoz-Cánoves
2   Centre de Regulació Genòmica (CRG), Programa de Diferenciació i Cancer, Barcelona, Spain
› Author Affiliations
Further Information

Publication History

Received 09 April 2003

Accepted after 09 June 2003

Publication Date:
05 December 2017 (online)

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Summary

Plasmin is a potent extracellular protease specialized in the degradation of fibrin (fibrinolysis). Active plasmin is generated by proteolytic activation of the zymogen plasminogen (Plg) by urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA). α-Enolase constitutes a receptor for plasminogen on several leukocyte cell types, serving to localize and promote plasminogen activation pericellularly. However, a role for α-enolase-type plasminogen receptor (PlgR) in myogenesis has never been demonstrated. In this study, we show that C2C12 mouse myoblasts express PlgR, being its expression greatly induced during the differentiation process. A monoclonal antibody against PIgR MAb 11G1, with cell surface-generated plasmin inhibitory abilities, was able to fully abrogate C2C12 myoblast fusion and differentiation in vitro. Moreover, both plasmin activity and PlgR expression were significantly induced in regenerating skeletal muscle in vivo, either in experimentally-injured muscle or in the dystrophic muscle of mdx mouse (an animal model of human Duchenne muscular dystrophy, DMD). The mdx muscle presents better regeneration capacities and less fibrosis than the human DMD muscle; therefore, the increase in PlgR/plasmin activity in mdx muscle suggests an important contribution of the fibrinolytic system in mdx regeneration. This study constitutes the first indication of α-enolase-type plasminogen receptor as an important component of skeletal myogenesis, by concentrating and enhancing plasmin generation on the cell surface.