Figure 6.
Long-term single-bulge cell lineage tracing. (A) Scheme of 1st telogen labelling and long-term chases. (B,E&H) Illustrative images from thick (60–90µm) skin sections show X-Gal staining in bulge (Bu) (yellow line) and bulb/germ (white line) compartments. Image in (E) shows a rare patch of frequent HF induction illustrating the coexistence of all 3 staining patterns in one skin region. Image in H shows bulb-only and bulge-only patterns after one year and at least 3 hair cycles post-labelling. The predominant patterns were complex (see counts in F). Scale bars, 50µm. (C&F) Quantification with SEM of X-Gal patterns at stages indicated. (D&G) Frequency of all labelled follicles counted at each stage (from data in Fig 4&Fig 6) show significant decline from one hair cycle to another.