Expression of VLA-4 and VLA-5 integrins in CXCR4⁺ nonadherent, adherent, and migrating CD34⁺ cells.

Transmigration of cultured CD34⁺ cells was assessed across Fn-coated filters, after which nonadherent (A,B), adherent (C,D), and migrating cells (E,F) were harvested. Cells were labeled with anti-CXCR4–PE together with anti–VLA-4–FITC or anti–VLA-5–FITC. Analysis of integrin expression was restricted to CXCR4-expressing cells by appropriate gating. Staining with isotype-matched IgG (dotted lines) and with anti–VLA-4 (left plots) or anti–VLA-5 (right plots) is shown in a representative experiment out of 5.