Expression of class-3 semaphorins and their receptors in the neonatal and adult rat retina.

Purpose: Semaphorins comprise a family of molecules that influence the growth and guidance of neuronal processes. Class-3 semaphorins are secreted proteins, and their effects are mediated by neuropilin (NP) and plexin (Plx) receptors. There is considerable information on mechanisms that influence axonal guidance and plasticity in the mammalian visual system, but a role for semaphorins has received less scrutiny.

Fate of multipotent neural precursor cells transplanted into mouse retina selectively depleted of retinal ganglion cells.

In some parts of the CNS, depletion of a particular class of neuron might induce changes in the microenvironment that influence the differentiation of newly grafted neural precursor cells. This hypothesis was tested in the retina by inducing apoptotic retinal ganglion cell (RGC) death in neonatal and adult female mice and examining whether intravitreally grafted male neural precursor cells (C17.2), a neural stem cell (NSC)-like clonal line, become incorporated into these selectively depleted retinae.

A new approach to CNS repair using chimeric peripheral nerve grafts.

We have examined whether transplanted freeze-thawed peripheral nerve (PN) sheaths repopulated ex vivo with purified adult Schwann cells (SCs) support the regeneration of adult rat retinal ganglion cell (RGC) axons. Cultured adult SCs were derived from donor rats or from the host animals themselves. We also transplanted PN sheaths filled with neonatal SCs or donor adult olfactory ensheathing glia (OEG).