Prospective isolation and characterization of committed and multipotent progenitors from immortalized mouse mammary epithelial cells with morphogenic potential

Table 1 Transplantation results of the CDβ-derived clones^a

Clone	Source	Progenitor potential	Outgrowth rate	Number of fat pads filled, n(%)
1	Bi	-	6/12	6 (50%)
2	Bi	-	0/12	No outgrowth
3	Bi	-	6/8	4 (25%)
				2 (75%)
4	Bi	-	7/7
5	Bi	-	0/9	No outgrowth
6	Bi	-	0/11	No outgrowth
7	SP-1	-	0/12	No outgrowth
8	SP-2	-	0/12	No outgrowth
9	SP-3	Alveolar	12/12	6 (50%)
				6 (25%)
10	SP-4	-	0/10	No outgrowth
11	NSP-1	Multipotent	12/12	6 (75%)
				6 (50%)
12	NSP-2	Ductal	7/10	6 (75%)
				1 (25%)
13	NSP-3	Luminal	0/6	No outgrowth
14	NSP-4	-	0/3	No outgrowth
15	NSP-5	Multipotent	5/8	2 (75%)
				3 (25%)

^aCDβ = COMMA-D cell line engineered to express β-galactosidase; No outgrowth = no discernible mammary structures; SP = side population; NSP = non-side population; Bi = biclonal, referring to the groups derived from a single SP cell and a single NSP cell. The groups were either derived from a single SP cell or a single NSP cell (clones 7 to 15) or were biclonal and derived from one SP mixed with one NSP (clones 1 to 6). Transplantation of clone 9 or SP-3 generated alveolar-only structures in vivo and was referred to as the alveolar progenitor clone. Transplantation of clone 12 or NSP-2 generated ductal-only structures and was referred to as the ductal progenitor clone. Clones 11 (NSP-2) and 15 (NSP-5) generated ducts and alveolar structures and were referred to as multipotent. Clone 13 or NSP-3 incorporated into the lumen when mixed with total mammary epithelial cells prior to transplantation and was referred to as luminal. Outgrowth take rate was calculated by dividing the number of positive fat pads containing any mammary outgrowths divided by the total number of fat pads transplanted. The number of fat pads filled refers to the percentage of fat pads containing mammary outgrowths. The numbers outside the parentheses refer to the number of fat pads containing a mammary outgrowth. The percentages inside the parentheses refer to the percentage of fat pads containing a mammary outgrowth.

ISSN: 1465-542X