Relaxin recruits BMDECs into areas of neovascularization. (A) Chimeric mice (wild-type mice with GFP BM) were implanted with Matrigel pellets impregnated with vehicle or rhRLX, as indicated, and after 7 days the pellets were isolated, embedded in paraffin, sectioned, and stained with DAPI, a pan-endothelial cell antigen monoclonal antibody MECA-32, anti-GFP, or isotype control antibodies as indicated and imaged using conventional fluorescent microscopy. (B) Same as panel A, except that slides were imaged using confocal microscopy. (C) Percentage of area that fluoresces red (by epifluorescence) indicating MECA-32 staining. Shown is average area of 3 fields from 6 different sections from 9 pellets for each treatment. *P < .001 by paired t test. (D) Percentage of area that expresses dual fluorescence (by epifluorescence) indicating dual MECA-32 and GFP staining. Shown is average area of 3 fields from 6 different sections from 9 pellets. *P < .001 by paired t test.