Anatomical localization of progenitor cells in human breast tissue reveals enrichment of uncommitted cells within immature lobules

Table 1 Summary of frequency of progenitor activity

Uncultured cells
Progenitor type	Progenitor lineage	mean ± sd	Frequency, number/1000 cells
Adherent progenitors (n = 19)
Total	Both	0.0098 ± 0.0023	9.8/1000
Bi-potent	Both	0.002 ± 0.0014	2/1000
Luminal progenitors	Luminal	0.0036 ± 0.004	3.6/1000
Basal progenitors	Basal	0.0029 ± 0.004	2.9/1000
Non-adherent progenitors
Mammospheres (n = 19)	Both	0.0067 ± 0.00092	6.7/1000
Floating colonies (n = 18)	Luminal	0.0048 ± 0.00088	4.8/1000
Structural progenitors (n = 13)
Total		0.003 ± 0.0006	3/1000
Luminal alveolar progenitor	Luminal	0.002 ± 0.003	2/1000
Basal ductal progenitor	Basal	0.0009 ± 0.0004	0.9/1000

ISSN: 1465-542X