Relaxin is a chemoattractant for CD34⁺ BMDEC migration. (A) CD34⁺ BMDECs migrate to increasing concentrations of rhRLX. *P < .001 versus 0 ng/mL rhRLX. Bar represents the mean (± SD) infrared (IR) fluorescence of migrating cells from 4 wells per rhRLX concentration. Shown is a representative of 4 experiments. (B) CD34⁺ BMDECs from 10 healthy persons that migrate to rhRLX (50 ng/mL) and SDF-1 (100nM) expressed as mean percentage (± SD) of cells in the lower chamber, above background migration. *P < .029 versus SDF-1. (C) CD34⁺ BMDECs were seeded in the upper Boyden chamber with either vehicle or 60 ng/mL of rhRLX in the top and/or bottom as indicated. Shown is mean percentage (± SD) of 3 wells of CD34⁺ BMDECs loaded to the top chamber that have migrated, after subtracting background. *P < .025 versus black bar.