Stable long-term transgene expression in all peripheral donor white blood cell types with preferential representation of NGFR⁺ cells in Gr-1⁺ and Mac-1⁺donor WBCs.

NGFR expression was analyzed by flow cytometry as in Figure 1. Data represented the mean percentage ± SEM of NGFR⁺ cells in peripheral blood of 7 mice from experiment 2 at various time-points after transplantation of bone marrow cells transduced with the 1171 vector. There were no significant declines (P < .05) in the percentage of NGFR⁺ cells within a given phenotypic cell population sampled after the second month after transplantation. Note that the frequency of NGFR⁺ cells was consistently greater in Ly5.2⁺Gr-1⁺ or Ly5.2⁺Mac-1⁺ myeloid cells than in all other cell types at each time-point. For Gr-1⁺ versus B220⁺, CD3e⁺, RBCs, or platelets,P < .001 (n = 7) at days 116 and 161, andP < 0.03 (n = 3) at day 249. For Mac-1⁺versus B220⁺, CD3e⁺, RBCs, or platelets,P < .009 (n = 7) at days 116 and 161, andP < .02 (n = 3) at day 249, except for Mac-1⁺versus B220⁺. All abbreviations are as in Figures 1 and2.