Targeted adoptive immunotherapy with engineered T cells is a promising treatment for
refractory hematologic malignancies. However, many patients achieving early complete
remissions ultimately relapse. Immunosuppressive ligands are expressed on tumor and
supportive cells in the tumor microenvironment (TME). When activated, T cells express
associated “checkpoint” receptors. Binding of co-inhibitory ligands and receptors may
directly contribute to T-cell functional exhaustion. It is not known whether all T cells …