A method for sterilising a platelet lysate in the liquid state comprising at least the endogenous growth factors TGF beta 1, EGF, PDGF-AB, IGF-1, VEGF and bFGF, said method comprising freezing said liquid platelet lysate in order to obtain a frozen platelet lysate and irradiating said frozen platelet lysate with ionising radiation in order to obtain a sterilised platelet lysate, said irradiation being adapted so as to preserve at least 80% of the concentration of at least one of the endogenous growth factors chosen from the group consisting of TGF beta 1, EGF, PDGF-AB, IGF-1 and VEGF.
