Compositions and methods are described for the delivery of recombinant human iduronate-2-sulfatase (IDS) produced by human neuronal or glial cells to the cerebrospinal fluid of the central nervous system (CNS) of a human subject diagnosed with mucopolysaccharidosis II (MPS II).

The present disclosure provides, among other things, a recombinant adeno-associated virus (rAAV) vector comprising an AAV8 or AAV9 capsid and a codon-optimized sequence encoding a human iduronate-2-sulfatase (I2S) enzyme. The disclosure also provides a method of treating a subject having Hunter syndrome (MPS II), comprising administering to the subject in need thereof a recombinant adeno-associated virus (rAAV) vector comprising an AAV8 or AAV9 capsid, and a promoter operably linked to a nucleic acid sequence that encodes iduronate-2-sulfatase (I2S), and wherein administering results in an increase in I2S enzymatic activity in the subject.

Certain embodiments provide a fusion protein comprising an iduronate 2-sulfatase (IDS) amino acid sequence, an IDS variant amino acid sequence, or a catalytically active fragment thereof; and an anti-transferrin receptor (TfR) antibody as described herein, as well as methods of use thereof.

Provided herein are fusion proteins that comprise an enzyme replacement therapy enzyme and an Fc region, as well as methods of using such proteins to treat a lysosomal storage disorder. Methods for transporting agents across the blood-brain barrier are also provided herein.

Described herein are engineered nucleases comprising mutations in the cleavage domain (e.g., FokI or homologue thereof) and/or DNA binding domain (zinc finger protein, TALE, single guide RNA) such that on-target specificity is increased.

Disclosed is a method for production of a fusion protein in which an antibody and a lysosomal enzyme are fused. The method comprises; (a) a step of culturing mammalian cells producing the fusion protein in a serum-free medium to let the mammalian cells secrete the fusion protein in the culture medium, (b) a step of collecting culture supernatant by removing the mammalian cells from the culture medium, and (c) a step of purifying the fusion protein from the culture supernatant by using a column chromatography employing as a solid phase a material to which a substance having affinity for the fusion protein has been bound, a column chromatography employing as a solid phase a material having affinity for the phosphate group, and a size exclusion column chromatography.

The present invention provides, among other things, improved methods for purifying I2S protein produced recombinantly for enzyme replacement therapy. The present invention is, in part, based on the surprising discovery that recombinant I2S protein can be purified from unprocessed biological materials, such as, I2S-containing cell culture medium, using a process involving as few as four chromatography columns.

The present invention provides, among other things, compositions and methods for CNS delivery of lysosomal enzymes for effective treatment of lysosomal storage diseases. In some embodiments, the present invention includes a stable formulation for direct CNS intrathecal administration comprising a heparan N-sulfatase (HNS) protein, salt, and a polysorbate surfactant for the treatment of Sanfilippo Syndrome Type A.

Provided herein are methods and compositions for treating a subject suffering from a deficiency in iduronate 2-sulfatase in the CNS. The methods include systemic administration of a bifunctional fusion antibody comprising an antibody that crosses the blood brain barrier (BBB) and an iduronate 2-sulfatase.

The present invention relates to nucleic acid cassettes for gene therapy, particularly to nucleic acid cassettes encoding therapeutic proteins in combination with exogenous signal peptides. The invention further relates to viral and non-viral vectors comprising such nucleic acid cassettes, and the use of such nucleic acid cassettes and vectors to increase expression of therapeutic proteins by airway cells.