Interleukin-15 in cancer immunotherapy: IL-15 receptor complex versus soluble IL-15 in a cancer cell-delivered murine leukemia model ==================================================================================================================================== * Alexandra Berger * Sarah J. Colpitts * Melanie S. S. Seabrook * Caren L. Furlonger * Maura B. Bendix * Joshua M. Moreau * William M. McKillop * Jeffrey A. Medin * Christopher J. Paige