T-cell autoimmunity to myelin basic protein was recently shown to be neurop
rotective in injured rat optic nerves. In the present study, using the mous
e optic nerve, we examined whether active immunization rather than passive
transfer of T-cells can be beneficial in protecting retinal ganglion cells
(RGCs) from post-traumatic death. Before severe crush injury of the optic n
erve, SJL/J and C3H. SW mice were actively immunized with encephalitogenic
or nonencephalitogenic peptides of proteolipid protein (PLP) or myelin olig
odendrocyte glycoprotein (MOG), respectively. At different times after the
injury, the numbers of surviving RGCs in both strains immunized with the no
nencephalitogenic peptides pPLP 190-209 or pMOG 1-22 were significantly hig
her than in injured controls treated with the non-self-antigen ovalbumin or
with a peptide derived from beta -amyloid, a non-myelin-associated protein
. Immunization with the encephalitogenic myelin peptide pPLP 139-151 was be
neficial only when the disease it induced, experimental autoimmune encephal
omyelitis, was mild. The results of this study show that survival of RGCs a
fter axonal injury can be enhanced by vaccination with an appropriate self-
antigen. Furthermore, the use of nonencephalitogenic myelin peptides for im
munization apparently allows neuroprotection without incurring the risk of
an autoimmune disease. Application of these findings might lead to a promis
ing new approach for treating optic neuropathies such as glaucoma.