TY - JOUR
T1 - Intracellular K+ Limits T-cell Exhaustion and Preserves Antitumor Function
AU - Collier, Camille
AU - Wucherer, Kelly
AU - McWhorter, Matthew
AU - Jenkins, Chelsea
AU - Bartlett, Alexandra
AU - Roychoudhuri, Rahul
AU - Eil, Robert
N1 - Publisher Copyright:
©2023 The Authors; Published by the American Association for Cancer Research.
PY - 2024/1/1
Y1 - 2024/1/1
N2 - T cells are often compromised within cancers, allowing disease progression. We previously found that intratumoral elevations in extracellular K+, related to ongoing cell death, constrained CD8+ T-cell Akt–mTOR signaling and effector function. To alleviate K+-mediated T-cell dysfunction, we pursued genetic means to lower intracellular K+. CD8+ T cells robustly and dynamically express the Na+/K+ ATPase, among other K+ transporters. CRISPR-Cas9–mediated disruption of the Atp1a1 locus lowered intracellular K+ and elevated the resting membrane potential (i.e., Vm, ψ). Despite compromised Ca2+ influx, Atp1a1-deficient T cells harbored tonic hyperactivity in multiple signal transduction cascades, along with a phenotype of exhaustion in mouse and human CD8+ T cells. Provision of exogenous K+ restored intracellular levels in Atp1a1-deficient T cells and prevented damaging levels of reactive oxygen species (ROS), and both antioxidant treatment and exogenous K+ prevented Atp1a1-deficient T-cell exhaustion in vitro. T cells lacking Atp1a1 had compromised persistence and antitumor activity in a syngeneic model of orthotopic murine melanoma. Translational application of these findings will require balancing the beneficial aspects of intracellular K+ with the ROS-dependent nature of T-cell effector function.
AB - T cells are often compromised within cancers, allowing disease progression. We previously found that intratumoral elevations in extracellular K+, related to ongoing cell death, constrained CD8+ T-cell Akt–mTOR signaling and effector function. To alleviate K+-mediated T-cell dysfunction, we pursued genetic means to lower intracellular K+. CD8+ T cells robustly and dynamically express the Na+/K+ ATPase, among other K+ transporters. CRISPR-Cas9–mediated disruption of the Atp1a1 locus lowered intracellular K+ and elevated the resting membrane potential (i.e., Vm, ψ). Despite compromised Ca2+ influx, Atp1a1-deficient T cells harbored tonic hyperactivity in multiple signal transduction cascades, along with a phenotype of exhaustion in mouse and human CD8+ T cells. Provision of exogenous K+ restored intracellular levels in Atp1a1-deficient T cells and prevented damaging levels of reactive oxygen species (ROS), and both antioxidant treatment and exogenous K+ prevented Atp1a1-deficient T-cell exhaustion in vitro. T cells lacking Atp1a1 had compromised persistence and antitumor activity in a syngeneic model of orthotopic murine melanoma. Translational application of these findings will require balancing the beneficial aspects of intracellular K+ with the ROS-dependent nature of T-cell effector function.
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U2 - 10.1158/2326-6066.CIR-23-0319
DO - 10.1158/2326-6066.CIR-23-0319
M3 - Article
C2 - 38063845
AN - SCOPUS:85181588816
SN - 2326-6066
VL - 12
SP - 36
EP - 47
JO - Cancer Immunology Research
JF - Cancer Immunology Research
IS - 1
ER -