Casitas B cell lymphoma-b (Cbl-b) is a member of the mammalian Cbl family of proteins which are characterized by an N-terminal tyrosine kinase binding domain, linker domain, RING finger domain, and a variable C-terminal domain.  Cbl-b is an E3 ubiquitin ligase that is critical for the proper regulation of various receptor tyrosine kinases and non-receptor tyrosine kinases.  Loss of function of Cbl-b has been linked to a variety of diseases including cancer, myeloproliferative disorders, and autoimmune diseases such as arthritis and type 1 diabetes mellitus.  Researchers at the University of Nebraska Medical Center have created a conditional knockout Cbl-b mouse model.  This novel mouse model allows for tissue specific knockdown of Cbl-b, which will be useful for exploring the role of Cbl-b in the development of autoimmune diseases.  These mice will also provide a model to assess the efficacy of new anti-inflammatory drugs and will be useful for the identification of new biomarkers and drug targets for autoimmune disorders.