| abstract |
An object of the present invention is a monoclonal that specifically recognizes and binds to the hinge region of a polypeptide encoded by the heavy chain gene of immunoglobulin A1, including a serinethreonine-binding sugar chain that does not bind galactose, which is effective for the diagnosis of IgA nephropathy. It is to provide an antibody. In addition, the monoclonal antibody or the antibody fragment which specifically recognizes and binds to the hinge region of the polypeptide encoded by the heavy chain gene of immunoglobulin A1 comprising a serinethreonine-binding sugar chain to which galactose is not bound, A diagnostic agent using the antibody or antibody fragment and a therapeutic agent containing the antibody or antibody fragment as an active ingredient can be provided. |