Release of (pro)platelet-like particles next to the vessels in ADAP-deficient mice. (A) Maximum projection of 60 µm z-stacks obtained by confocal microscopy from sternal BM of control and ADAP-deficient mice. Vessels (red; CD105), MKs (cyan; GPIX). Sternum was fixed and cleared for imaging. Scale bars represent 50 µm (top panel; left) and 20 µm (bottom panel; left). Bottom panel, Digital magnification of the region marked in the top panel. (i, ii) Maximum projection of a 25 µm z-stack from a sternum of an ADAP-deficient mouse. Scale bars represent 30 µm (i) and 10 µm (ii). Arrowheads in (ii) point to proplatelets released into the BM compartment. (B) Intravital 2-photon microscopy of proplatelet formation in the skull at the indicated time points. Vessels were visualized by staining of CD105 and with tetramethylrhodamine-dextran (TMR-dextran; red); MKs/platelets are shown by GPIX staining (green). Scale bars represent 50 µm (top and middle panel) and 10 µm (bottom panel). Arrowheads point to proplatelets (top and middle panel), arrows point to platelet-like particle released into the BM compartment (bottom panel) in the region marked with an asterisk (middle panel, left).