Sequestration of T cells in bone marrow in the setting of glioblastoma and other intracranial tumors
Authors: Pakawat Chongsathidkiet, Christina Jackson, Shohei Koyama, Franziska Loebel, Xiuyu Cui, S. Harrison Farber, Karolina Woroniecka, Aladine A. Elsamadicy, Cosette A. Dechant, Hanna R. Kemeny, Luis Sanchez-Perez, Tooba A. Cheema, Nicholas C. Souders, James E. Herndon, Jean-Valery Coumans, Jeffrey I. Everitt, Brian V. Nahed, John H. Sampson, Michael D. Gunn, Robert L. Martuza, Glenn Dranoff, William T. Curry, Peter E. Fecci
Summary:
T cell dysfunction contributes to tumor immune escape in patients with cancer and is particularly severe amidst glioblastoma (GBM). Among other defects, T cell lymphopenia is characteristic, yet often attributed to treatment. We reveal that even treatment-naïve subjects and mice with GBM can harbor AIDS-level CD4 counts, as well as contracted, T cell–deficient lymphoid organs. Missing naïve T cells are instead found sequestered in large numbers in the bone marrow. This phenomenon characterizes not only GBM but a variety of other cancers, although only when tumors are introduced into the intracranial compartment. T cell sequestration is accompanied by tumor-imposed loss of S1P1 from the T cell surface and is reversible upon precluding S1P1 internalization. In murine models of GBM, hindering S1P1 internalization and reversing sequestration licenses T cell–activating therapies that were previously ineffective. Sequestration of T cells in bone marrow is therefore a tumor-adaptive mode of T cell dysfunction, whose reversal may constitute a promising immunotherapeutic adjunct.
Source: Nature Medicine, 2018
Summary:
T cell dysfunction contributes to tumor immune escape in patients with cancer and is particularly severe amidst glioblastoma (GBM). Among other defects, T cell lymphopenia is characteristic, yet often attributed to treatment. We reveal that even treatment-naïve subjects and mice with GBM can harbor AIDS-level CD4 counts, as well as contracted, T cell–deficient lymphoid organs. Missing naïve T cells are instead found sequestered in large numbers in the bone marrow. This phenomenon characterizes not only GBM but a variety of other cancers, although only when tumors are introduced into the intracranial compartment. T cell sequestration is accompanied by tumor-imposed loss of S1P1 from the T cell surface and is reversible upon precluding S1P1 internalization. In murine models of GBM, hindering S1P1 internalization and reversing sequestration licenses T cell–activating therapies that were previously ineffective. Sequestration of T cells in bone marrow is therefore a tumor-adaptive mode of T cell dysfunction, whose reversal may constitute a promising immunotherapeutic adjunct.
Source: Nature Medicine, 2018