I am not sure about Jurkat cells, but our lab used mouse IL-4Rα antibodies from Santa Cruz Biotechnology for immunoblotting of primary murine cells or organs (bone marrow derived macrophages, MEF, tracheal epithelial tissue, lungs and others). The following paper is about IL4 receptor regulation and details the materials/ antibodies (the antibodies are listed in the supplementary section):
Regulation of IL-4 Receptor Signaling by STUB1 in Lung Inflammation.