Fig. 4.
Mono-Q-Sepharose profiles of cytosolic (A) and membrane (B) fractions from normal (•) and PV (○) ECFC. Day-6 ECFC were collected and lysed with a Dounce homogenizer in buffer A without Triton X-100. Cytosolic and membrane fractions were obtained by ultracentrifugation at 100,000g for 60 minutes as described in Materials and Methods. Approximately 1 mg samples were loaded on the mono-Q column. PTP activity was measured with 32P-labeled ENDYINAL and the data are expressed as cpm obtained from 2 μL of each 0.5-mL fraction eluted from the column. A representative figure from three experiments with similar results is shown. Each experiment was performed with blood samples from different normal volunteers and PV patients.