CFU-C/mL blood from control +/+ littermate mice and from Sl/Sl^d and W/W^v mice before and after anti-VLA4 and anti–VCAM-1 treatment (see Materials and Methods for details). Sl/Sl^d mice respond to anti-VLA4 similarly to controls (P = .35), in contrast to W/W^v mice which showed a blunted response (P < .0016). Both types of mutant mice did not respond to anti–VCAM-1 treatment, in contrast to their +/+ littermates. *Indicates significant differences from control responses (P < .05) and numbers above each column indicate the number of mice treated.