Time- and pH-dependent release of PDGF and TGF-beta from platelets in vitro.
We studied the spontaneous and thrombin-induced activation of platelets and their release of platelet derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) at different pH values. Platelet activation was assayed with antibodies against P-selectin and performed in serum-free media. The release of PDGF and TGF-beta was determined by ELISA after 15 min and 12h. There was no activation at pH 5.0, while a time-dependent release of growth factors occurred at neutral and alkaline pH. The results suggest that release o f growth factors is not only dependent on platelet activation but also on incubation time and pH. Although the used serum-free experimental situation is different from normal conditions for platelets in vivo, the findings of a late release of growth factors may, nevertheless, be relevant to wound healing.
Liu
Yawei
Y
Division of Pathology II, Faculty of Health Sciencee, Linköping University, Sweden.
Kalén
Anders
A
Risto
Olof
O
Wahlström
Ola
O
D001792:Blood Platelets / Q000378:metabolism*; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015539:Platelet Activation; D010982:Platelet-Derived Growth Factor / Q000032:analysis / Q000378:metabolism*; D013917:Thrombin; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000378:metabolism*; D014945:Wound Healing
D010982:Platelet-Derived Growth Factor; D016212:Transforming Growth Factor beta; D013917:Thrombin