Impaired activation of the PI3 kinase/Akt pathway in platelets from JAK2V617F-ositive ET patients. Washed platelets from control and ET patients were stimulated with the indicated concentrations of thrombin (A, n = 5, B, n = 6) and SFLLRN (C, n = 5, D, n = 10) for 2 minutes before extraction in 4× NuPage lysis buffer and immunoblotting with the indicated antibodies. (i) A representative blot is shown. (ii) The bar graphs (average ± SEM) show the fold-increase in pAkt^T308 and p-PLK stimulation and are corrected for total Akt and pleckstrin levels.