Fusion proteins for delivery of gdnf to the cns

Abstract

The invention provides compositions, methods, and kits for increasing transport of GDNF across the blood brain barrier while allowing its activity to remain substantially intact. The GDNF is transported across the blood brain barrier via one or more endogenous receptor-mediated transport systems.

1 .- 28 . (canceled) 
     
     
         29 . A composition comprising alpha-L-iduronidase (IDUA) covalently linked to the amino terminus of an antigen binding fragment of an antibody or to an antibody fragment binding to a transferrin receptor that is capable of crossing the blood brain barrier (BBB), wherein the composition is capable of producing an average elevation of concentration in the brain of the IDUA of at least about 1 ng/gram brain following intravenous administration, and wherein the composition comprises a mineral acid salt or a salt of an organic acid.