FIG. 4.

Telomere length analysis of fresh BM cells and splenocytes from SCID and wild-type (wt) mice. (A) Flow-FISH. Telomere fluorescence (in arbitrary units [a.u.]) of splenocytes and BM cells as measured by flow cytometry for five different SCID and wt mice is shown. The average telomere lengths and standard deviations are indicated. The statistical significance of the difference in telomere fluorescence between SCID and wt mice is indicated by the Student's t test numbers (P). (B) TRF analysis. BM from wt and SCID mice in the same genetic background (see Materials and Methods) was used for TRF analysis. Notice that TRFs were dramatically elongated in SCID mice compared with wt controls.