In vitro culture of the eye and the retina of the mouse and rat.

STRANGE WAYS & FELL (1926) and Dorris (1938) showed that embryonic chick eyes could be cultivated successfully in vitro on plasma clots, and Harrison (1951) and Reinbold (1954) obtained satisfactory results with an agar-tyrode medium containing embryo extract. The retina in these eyes was undifferentiated and, though little or no increase in the size of the eyes occurred, the authors agreed that cytological differentiation proceeded at a more or less normal rate. Tansley (1933) reported the successful cultivation on plasma clots of whole eyes from rat embryos of 14-17 days and of isolated retina from rats up to 5 days old. Cytological differentiation proceeded at a normal rate, at least for the first few days in culture, but excessive growth of mesodermal elements tended to occur after 12 to 14 days. Rosette formation was a prominent feature in these cultures. The present work differs from previous studies in that most of the material cultured was more mature and a fluid medium free from embryo extract has been used. The maturity of the material was governed chiefly by the fact that it is at this stage of retinal differentiation that retinal dystrophies, which will be the subject of a separate study, occur (Sorsby et al., 1954; Lucas et al., 1955).