Evaluating alternative stem cell hypotheses for adult corneal epithelial maintenance

Table 2 Examples of marker gene expression differences between the basal limbal and corneal epithelia during normal homeostasis identified by immunostaining

Positive markers			Negative markers
Marker	Species	Ref.	Marker	Species	Ref.
Integrin α9	Mouse, human	[3,105,106]	Keratin 3	Rabbit	[4]
∆Np631	Human	[3,107,108]	Keratin 3/Keratin 12	Human	[3,108]
∆Np63α	Human	[96]	NGF receptor (p75NTR)	Human	[3]
ABCG2	Human, rat, rabbit	[3,57,91-93,108]	Involucrin	Human	[3]
Vimentin	Human	[108]	Connexin 43	Human	[3,108]
Keratin 19	Human, mouse	[108,109]	E-cadherin	Human	[3]
Keratin 15	Human, mouse	[109]	Nestin	Human	[108]
N-cadherin	Human	[110]
Bmi1	Human	[111]
C/EBPδ	Human	[111]
ABCB5	Human, mouse	[54]

¹ΔNp63 is not expressed in the human basal corneal epithelium[107] but it is expressed in mouse and rat corneal epithelia[27,112,113]. Positive markers are expressed in basal limbal but not basal corneal epithelium. Negative markers are expressed in basal corneal but not basal limbal epithelium.