Abstract: Provided, in part, are an anti-human transferrin receptor antigen-binding proteins and fusion proteins comprising an anti-human transferrin receptor antigen-binding proteins (e.g., in scFv, Fab or antibody format) which may be fused to a payload for delivery of the payload to a targeted tissue (e.g., past the blood-brain barrier and to the brain). Payloads include, for example, alpha-glucosidase (GAA) polypeptide. Methods for treating various diseases with such molecules, e.g., glycogen storage diseases, such as Pompe Disease, with the fusions are provided.

Abstract: Provided herein are monoclonal antibodies that bind to the transmembrane serine protease 6 (TMPRSS6) protein, and methods of use thereof. In various embodiments of the disclosure, the antibodies are fully human antibodies that bind to TMPRSS6. In some embodiments, the antibodies disclosed herein are useful in a method for treating or preventing a disease, disorder or condition associated with TMPRSS6 in humans.