Plasma-derived microvesicles (MVs) from MRL/lpr mice expose a higher amount of chromatin and contain a higher percentage of annexin V++/CD3+ and annexin V++/CD19+ MVs. (A) The concentration of apoptotic MVs derived from 32Dcl3 cells determined in flow cytometry using counting beads (y-axis) was compared to the protein concentration of the same MV samples measured by the BCA assay (x-axis). (B) The concentration of MVs isolated from apoptotic 32Dcl3 cells, brought to a concentration of 100 μg protein/ml, and from plasma of 8- to 10-week-old BALB/c and MRL/lpr mice were determined by flow cytometry. (C) Representative forward scatter/side scatter (FSC/SSC) plots obtained from plasma-derived MVs of a BALB/c and MRL/lpr mouse to demonstrate comparable MV populations. (D) The percentage of MVs positive for Annexin V, anti-CD3-PE or anti-CD19-PE, was measured by flow cytometry for MRL/lpr mice in comparison to BALB/c mice (both n = 8). (E,
F) Flow cytometry of plasma-derived MVs from BALB/c and MRL/lpr mice after staining with the indicated mAbs. The percentage positive MVs (E) and the mean fluorescence intensity (MFI) (F) of MRL/lpr MVs was compared to BALB/c microvesicles. *P <0.05; **P <0.01.