Abstract: A transgenic non-human mammal with a disruption in its IL-21 receptor gene is provided, along with methods of using the transgenic non-human mammal.

Abstract: Agents (e.g., antibodies and fragments thereof) that bind specifically to IL 13 and modulate the ability of IL-13 to interact with IL-13 receptors and signaling mediators are disclosed.

Abstract: This application relates to antibodies, e.g., humanized antibodies, and antigen-binding fragments thereof, that bind to interleukin-13 (IL-13), in particular, human IL-13, and their uses in regulating immune responses mediated by IL-13. The antibodies disclosed herein are useful in diagnosing, preventing, and/or treating a subject, e.g., a human patient, one or more IL-13-associated disorders, e.g., respiratory disorders (e.g., asthma); atopic disorders (e.g., allergic rhinitis); inflammatory and/or autoimmune conditions of the skin (e.g., atopic dermatitis), and gastrointestinal organs (e.g., inflammatory bowel diseases (IBD)), as well as fibrotic and cancerous disorders.

Abstract: Methods and compositions for inhibiting interleukin-21 (IL-21)/IL-21 receptor (MU-1) activity using antagonists of IL-21 or IL-21 receptor (“IL-21R” or “MU-1”), are disclosed. IL-21/IL-21R antagonists can be used to induce immune suppression in vivo, e.g., for treating, ameliorating or preventing autoimmune or inflammatory disorders, including, e.g., inflammatory bowel disease (IBD), rheumatoid arthritis (RA), transplant/graft rejection, psoriasis, asthma, fibrosis, and systemic lupus erythematosus (SLE).

Abstract: An IL-21 polypeptide or other IL-21 pathway agonist can be used to treat atopic disorders, e.g., asthma.

Abstract: Methods for agents useful for treating asthma are disclosed. The methods include screening for agents that inhibit the production of a PKC-? protein, as well as for agents that inhibit the kinase activity of a PKC-? protein, or a functional fragment thereof, wherein such agents are useful for treating asthma. The methods also include screening for agents that inhibit the production of a reporter gene product encoded by a nucleic acid sequence operably linked to a PKC-? promoter. Also disclosed are methods of treating asthma that include administering an agent that inhibits the production of a functional PKC-? protein or the kinase activity of a PKC-? protein or a functional fragment thereof. An isolated mast cell lacking expression of endogenous PKC-? is also disclosed.

Abstract: A transgenic non-human mammal with a disruption in its IL-21 receptor gene is provided, along with methods of using the transgenic non-human mammal.