IL-15R ALPHA FORMS, CELLS EXPRESSING IL-15R ALPHA FORMS, AND THERAPEUTIC USES OF IL-15R ALPHA AND IL-15/IL-15R ALPHA COMPLEXES

摘要

In one aspect, described herein are cyclical administration regimens for the administration of complexes comprising interleukin-15 ("IL-15") covalently or noncovalently bound to IL-15 receptor alpha ("IL-15Ra") to patients in order to enhance IL-15-mediated immune function. In a specific aspect, the cyclical administration regimens are useful in the prevention, treatment, and/or management of disorders in which enhancing IL-15-mediated function is beneficial, such as cancer, infectious diseases, immune deficiencies and lymphopenia. Also described herein are purified soluble forms of IL-15Ra, cells that recombinantly express soluble forms ofiL-15Ra, and compositions comprising complexes of IL-15 covalently or non-covalently bound to soluble forms ofiL-15Ra. Further described herein are host cells that recombinantly express IL15-Ra derivatives comprising a mutation or deletion in the extracellular domain cleavage site, including IL-15Ra derivatives comprising the extracellular domain of IL-15Ra and a transmembrane domain of a heterologous molecule.