Reduced BM homing of Eμ-TCL1^Tg;Rhoh^−/−CLL cells. (A) The number of CD3⁻/CD5⁺/IgM⁺CLL cells was determined by flow cytometry and the ratio of CLL cells detected in the BM to number of injected CLL cells was calculated. (B) The ratio of CLL cells detected in the PB to number of injected CLL cells was calculated. (A-B) Data show mean ± SEM of CLL cells homing to the BM and circulating in the PB 16 hours after injection of 20 to 25 × 10⁶ CLL cells (WT versus Rhoh^−/−, mean ± SEM, **P = .004 and P = .2, Mann-Whitney U (MWU) test, n = 6 recipients). (C) The number of CD3⁻/CD5⁺ CLL cells was determined in the PB of recipients by flow cytometry. Data show mean ± SEM of CLL cells circulating in the PB 4 weeks after transplantation of 2 × 10⁷ CLL cells (WT versus Rhoh^−/−, mean ± SEM, **P = .004, MWU test, n = 6 recipients/group). (D) Comparison of survival of Rag2^−/−/IL2γ^−/− recipients 8 weeks after transplantation. (E) Data show mean ± SEM of CD3⁻/CD5⁺ CLL cells circulating in the PB 3 weeks after transplantation as assessed by flow cytometry (WT versus Rhoh^−/−, mean ± SEM, *P < .05, MWU test, n = 6 recipients/group). (F) Bars indicate mean ± SEM of total BM cells 3 weeks after transplantation (WT versus Rhoh^−/−, mean ± SEM, *P < .05, MWU test, n = 6 recipients/group) and (G) CLL cells present in the BM (WT versus Rhoh^−/−, mean ± SEM, *P < .05, MWU test, n = 6 recipients/group). (H) Data show mean ± SEM of spleen weights in recipients 3 weeks after transplantation (WT versus Rhoh^−/−, mean ± SEM, *P < .05, MWU test, n = 6 recipients/group).