Studies in mouse models of night blindness have demonstrated
that vision can be restored by transplanting rod precursor cells
taken from mouse neonates directly into the retina of recipient
animals. The University College London (UCL) Institute of
Ophthalmology-led team showed that the transplanted rod cells
made synaptic connections with the existing retinal circuitry,
were light responsive, and generated visual signals. The
transplantation built on their previous photoreceptor
transplantation research, and was optimized to increase the
number of cells that integrated in the retina. Critically, a
range of tests in animals receiving the transplants confirmed
that the treatment restored vision. The level of apparent visual
correction correlated with the number of functional transplanted
cells, and some restoration of vision was achieved even when the
numbers of integrated photoreceptors accounted for less than 1%
of the total rods in the retina. And while the reported studies
used donor cells taken from newbor