HARVEST AND STORAGE OF ADULT HUMAN PHOTORECEPTOR CELLS - THE VIBRATOME COMPARED TO THE EXCIMER-LASER

Purpose. To develop a method using the vibratome and the excimer laser to harvest a sheet of human photoreceptor cells from the retinas of c adaveric donors.Methods. Adult human photoreceptor cells were harveste d as intact sheets from the retinas of cadaver eyes using a vibratome or excimer laser. The sheets were embedded in 50% gelatin (in minimum essential medium and 300 mM sucrose) and stored at 4 degrees C. The mo rphology, integrity, viability and sterility of the harvested photorec eptor cells was studied. Results. Light and scanning electron microsco py demonstrated sheets of adult human photoreceptor cells with an oute r nuclear layer and inner and outer segments with either method of har vest. The initial viability of the outer nuclear layer, harvested an a verage of 28.2 h after death, was greater than or equal to 94.7%. Shee ts stored up to 72 h after harvest maintained a viability of greater t han or equal to 86.5%. The sheet of cells harvested with the vibratome frequently fragmented (n = 25, 35%) during passage through the delive ry cannula in contrast to the excimer laser. Harvested sheets were ste rile when the gelatin powder was irradiated prior to reconstitution. C onclusions. Intact, viable adult human photoreceptor cell sheets can b e isolated from the retina of a cadaver using either the vibratome or the excimer laser and stood up to 72 h at 4 degrees C. With the vibrat ome, there is damage to the outer segments of the photoreceptors, the sheets are fragile, and the harvest of specimens is time-consuming as only one or two specimens can be harvested from a single donor retina. These technical limitations are avoided with the excimer laser.