Figure 1. Adhesion Assay with Antibody Blocking of ICAM-1 in Pluripotent Stem Cell (PSC)-Derived Cardiovascular Cells.

(A) The U937 monocytic cell line was stained with LFA-1 (CD11a/CD18) and MAC-1 (CD11b/CD18) alpha chain antibodies. (B) PSCs (H9 embryonic stem cell line) were differentiated into high-purity endothelial cells (ECs) (>85% CD31+CD144+), stimulated with TNFα (10ng/ml) and IFNγ (50ng/ml) for 48 hours, followed by incubation with anti-human ICAM-1 blocking antibody (αICAM-1) (0.5mg/ul) for 1 hour at 37°C, and washed. U937 cells (labeled with fluorescent Calcein AM dye) were then incubated on the ECs for 20 minutes to allow binding, washed to remove any unbound U937 cells, and imaged. Image analysis via ImageJ (version 1.54g) showed binding of U937 cells to target PSC-derived ECs, (C) PSC-derived cardiomyocytes (CMs), and (D) PSC-derived cardiac fibroblasts (cFibs) following antibody blocking compared to unblocked controls. **** = p<0.0001, BR=3. Statistical analysis performed via Prism 10.2.2. ROI = Region of Interest