Engraftment of MSCV-β-gal-GFP-transduced BMCs. (A-B) GFP expression in red blood cells (□), platelets (▦), and WBCs (▪) demonstrated consistent, long-term expression of the transgene as long as 6 months after primary transplantation (1 month, n = 7; 3 months, n = 10; 6 months, n = 6) and as long as 9 months after secondary transplantation (1 month, n = 3; 3 months, n = 3; 6 months, n = 3; 9 months, n = 3). (C-D) Analyses of β-gal activity in systemic tissues of treated mice revealed a significantly higher level of expression of the corrective enzyme after primary (Glb1^+/+, n = 7; Glb1^-/-, n = 5; 1 month, n = 7; 3 months, n = 8; 6 months, n = 8) and secondary transplantation (Glb1^+/+, n = 7; Glb1^-/-, n = 3; 1 month, n = 3; 3 months, n = 3; 6 months, n = 3; 9 months, n = 3) compared with Glb1^-/- untreated mice. (E) The β-gal activity was higher in the HMF (hindbrain, midbrain, and forebrain), brain stem, cerebellum, and spinal cord of Glb1^-/- mice that underwent primary transplantation and in the brainstem, cerebellum, and spinal cord of Glb1^-/- mice that underwent secondary transplantation compared with untreated Glb1^-/- mice. Data are expressed as mean ± SD; groups were compared by one-way repeated measures analysis of variance (ANOVA). ^*P < .001 and ^#P < .05 relative to untreated Glb1^-/- littermates at the same age; post hoc Tukey test.