TN-C coating enhances the in vitro proliferation and expression of cell-cycle–promoting genes in HSPCs in an integrin α9–dependent manner. (A-E) Short-term BrdU incorporation assay for LSK cells cultured for 48 hours on slides coated with FN alone, FN plus full-length TN-C (FN + TN-C), or FN plus TN-C^FNIII (FN + TN-C^FNIII) with functional integrin α9 Abs (55A2C) or nonfunctional integrin α9 Abs (18R18D). (F) Percentage of BrdU⁺LSK cells in panels A-E (n = 4). (G) Relative mRNA expression for the cell-cycle regulators c-myc, cyclinD1, cyclinD2, cyclinD3, cyclinE1, cyclinE2, cyclinG1, cyclinG2, p57^Kip2, p18^Ink4c, p21^Cip1, and p16^Ink4a (n = 4). *P < .05.