CD73, a novel cell surface antigen that characterizes retinal photoreceptor precursor cells.
OBJECTIVE
The authors sought to identify cell surface markers of photoreceptor and its precursor cells.


METHODS
The expression of surface CD antigens that label both temporally and spatially distinct populations of mouse retinal cells were examined. Of the antibodies that showed positive signals in retinal cells, CD73 was focused on for more detailed analyses.


RESULTS
Mouse retinal subpopulations that expressed CD73 first appeared around birth and subsequently increased dramatically in number, eventually representing more than 90% of the retinal cells in the adult. CD73(+) cells were postmitotic and mostly rhodopsin-negative at postnatal day 1. However, in the adult retina, most of these cells expressed rhodopsin but not s-opsin. In reaggregation cultures, CD73(+) cells differentiated into rhodopsin-positive cells more rapidly than CD73(-) cells, which supports the idea that CD73 is an early photoreceptor lineage marker. The effects of ectopic expression in retinal cells of Nrl and Crx, both of which are transcription factors known to be expressed in photoreceptor lineage, suggest that CD73 is genetically downstream of Crx in the rod cell differentiation lineage. Adult retina of the common marmoset monkey also showed correlation of the expression pattern of rhodopsin and CD73.


CONCLUSIONS
CD73 is a cell surface marker of cone/rod common precursors and mature rod cells in mice and is genetically localized between Nrl and Crx. The expression of CD73 was conserved in primate rod cells, and CD73 provides an useful tool to purify photoreceptor cells for transplantation aimed at the regeneration of photoreceptors.
Koso
Hideto
H
Department of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
Minami
Chiharu
C
Tabata
Yoko
Y
Inoue
Mariko
M
Sasaki
Erika
E
Satoh
Shinya
S
Watanabe
Sumiko
S
D015720:5'-Nucleotidase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000954:Antigens, Surface / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics; D015415:Biomarkers / Q000378:metabolism*; D002144:Callithrix; D002454:Cell Differentiation / Q000502:physiology; D019070:Cell Lineage; D049109:Cell Proliferation; D005136:Eye Proteins / Q000235:genetics; D005434:Flow Cytometry; D015870:Gene Expression; D018398:Homeodomain Proteins / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008813:Mice, Inbred ICR; D008822:Mice, Transgenic; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012243:Rhodopsin / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics
D000954:Antigens, Surface; D050976:Basic-Leucine Zipper Transcription Factors; D015415:Biomarkers; D005136:Eye Proteins; D018398:Homeodomain Proteins; C084884:Nrl protein, mouse; D012333:RNA, Messenger; D015534:Trans-Activators; C109288:cone rod homeobox protein; D012243:Rhodopsin; D015720:5'-Nucleotidase