Maintenance and Neuronal Differentiation of Chicken Induced Pluripotent Stem-Like Cells

Table 2

Induced pluripotent stem cell rate of passage survival in different media conditions.

Passage	Chicken					Mouse
	BRL-C. plus	cESC	2i+	cESC 2i+	2i+ mod.	cESC	2i+ mod.
1	2/4	4/4	4/4	4/4	2/2	4/4	1/1
2	0/2	4/4	3/4	4/4	8/8	4/4	4/4
3	—	3/4	2/2	3/4	4/4	4/4	4/4
4	—	4/4	2/2	2/2	4/4	4/4	4/4
5	—	0/4	0/2	1/2	3/4	4/4	4/4
6	—	—	—	0/2	4/4	4/4	4/4
7	—	—	—	—	4/4	4/4	4/4
8	—	—	—	—	4/4	4/4	4/4

Each row indicates a passage from the previous row. The numerator of the fraction indicates the number of cultures (wells/plates) that survived the passage, and the denominator represents the number of cultures started in that passage. A “—” sign indicates that no cells survived to make it to that passage. During each passage, if the cultures were highly proliferative, each well or plate of cells was expanded into 4 other wells/plates; if they had a low level of proliferation, they were only expanded to 2 others; if they were not proliferating, they were necessarily passaged undiluted from one well to another until the cells senesced. The denominator of the cell immediately inferior indicates the ratio at which the cells were split. We tried increasing or decreasing cell concentration for those cultures that stopped proliferating, but this did not prevent them from senescing. The chicken iPSC-like cells in our modified 2i+ media (2i+ mod.) and our own mouse iPSC in KO-DMEM media have both made it past 20 passages (not shown).