Stimulation of CB CD34⁺ cell adhesion to HUVECs by SLPs. Calcein-AM–labeled CD34⁺ cells were not preincubated (left panel) or were preincubated with SLPs (3% vol/vol) (right panel) or with SDF-1 and subsequently were layered over HUVECs. After 30 minutes, nonadherent cells were removed, and adherent cells were counted using a spectrophotofluorimeter. (Upper panel) Relative fluorescence intensity. (Lower panel) Inverted microscope analysis of fluorochrome-labeled adhered cells. Cells were examined using Nikon Eclipse TS100 inverted microscope equipped with ELWD epifluorescence attachment (Nikon Instruments Inc., NY, USA), and digital images were captured using an Olympus DP10 camera (Olympus America). Original magnification 100 × (objective 20 ×, N.A 0.45). Data from 3 separate experiments were pooled together. Values shown are mean ± SD. *As compared with SDF-1 low dose.