504 As the disease progression and endpoint were significantly delayed following chronic intraspinal injection of exogenous wild-type hSOD1 in the SOD1G93A rat, it was suggested that extracellular SOD1 has neuroprotective effects in ALS.501 Mutant TAR DNA binding protein-43 (TDP-43) is also associated with the development of frontotemporal lobar degeneration and ALS. Here, SOD1 is linked to amyotrophic lateral sclerosis.