Cone Properties of Retinal Margin Cells in the Monkey (Macaca mulatta)

• Published in: Investigative ophthalmology & visual science Vol. 41; no. 8; pp. 2019 - 2022
• Main Authors: Chen, Xiaoming, Wikler, Kenneth C, MacLeish, Peter R
• Format: Journal Article
• Language: English
• Published: Rockville, MD ARVO 01.07.2000; Association for Research in Vision and Ophtalmology
• Subjects: Aging; Animals; Antibodies, Monoclonal; Biological and medical sciences; Biomarkers - analysis; Cell Count; Eye and associated structures. Visual pathways and centers. Vision; Eye Proteins - analysis; Fluorescent Dyes; Fundamental and applied biological sciences. Psychology; Macaca mulatta; Retina - chemistry; Retina - cytology; Retinal Cone Photoreceptor Cells - chemistry; Retinal Cone Photoreceptor Cells - cytology; Rod Opsins - immunology; Synaptic Vesicles - immunology; Vertebrates: nervous system and sense organs; Cone; Monkey; Synaptic vesicle; Retina; Macaca mulatta; Properties; Ripening; Visual system; Vertebrata; Labelled antibody technique; Mammalia; Cell population; Animal; Distribution; Primates; Simioidea; Opsin; Developmental stage
• ISSN: 0146-0404; 1552-5783

To characterize a cell population in the monkey retinal margin that was labeled with a cone-specific antibody and to determine the presence of additional markers. Retinal whole-mount preparations from infant and adult rhesus monkeys (Macaca mulatta) were immunolabeled by incubation overnight with the primary antibodies 7G6, a cone-specific antibody; SV2, a synaptic-vesicle antibody; and opsin antibodies that recognize either the short or long/middle wavelength-sensitive opsins. The retinal margin cells labeled by 7G6 lay within 1 mm of the ora serrata and differed from 7G6-labeled cones in the central retina. The margin cells possessed a soma, a fiber process, and a terminal enlargement that lay in the plane of the retina; no outer segment was discernible. A total of 5400 and 7252 margin cones cells were found in each of two monkeys. The terminal enlargement and soma of the labeled margin cells also showed SV2 immunoreactivity. Surprisingly, opsin immunoreactivity extended throughout the margin cell, which is consistent with the absence of a discernible outer segment. Cells with immunoreactive cone properties were found in the margin of the monkey retina. The absence of an outer segment and the presence of somatic opsin and SV2 are reminiscent of features observed in the central cones of fetal monkey retinas. These results suggest that a subpopulation of cones in the retinal margin might fail to mature completely and thus retain juvenile characteristics into adulthood.