Figure 3.
Telomere lengths and proliferation assays for MEFs and hematopoietic cells. (A) Terminal restriction fragments from mTERT Tg MEFs or non-Tg littermate MEFs were resolved by field inversion gel electrophoresis. MEF cultures were from littermate embryos from the A mTERT Tg line (lanes 1–3) and the B Tg line (lanes 4–7). (B) Mean telomere lengths are shown in adjacent bar graph, 50 kb non-Tg mice and 70 kb for TERT Tg littermates (P = 0.018 by Student's t test). (C) 3T9 assay on independent MEF cultures from wild-type embryos (gray circles) and littermate TERT Tg embryos (black triangles). Each point represents the mean of 13 independent cultures from mTERT Tg MEFs (7 from line A and 6 from line B) or the mean of 12 independent cultures from littermate non-Tg controls. Mitogen proliferation assays from thymocytes and splenocytes (D) and bone marrow cells (E). Cells were stimulated with the indicated mitogens and proliferation was assayed by measuring incorporation of [3H]thymidine. Each bar represents the mean of triplicates. Error bars show SD.