Purinergic P2X4 receptors and mitochondrial ATP production regulate T cell migration
Carola Ledderose, … , Gary A. Visner, Wolfgang G. Junger
Carola Ledderose, … , Gary A. Visner, Wolfgang G. Junger
Published June 12, 2018
Citation Information: J Clin Invest. 2018;128(8):3583-3594. https://doi.org/10.1172/JCI120972.
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Research Article Cell biology

Purinergic P2X4 receptors and mitochondrial ATP production regulate T cell migration

Abstract

T cells must migrate in order to encounter antigen-presenting cells (APCs) and to execute their varied functions in immune defense and inflammation. ATP release and autocrine signaling through purinergic receptors contribute to T cell activation at the immune synapse that T cells form with APCs. Here, we show that T cells also require ATP release and purinergic signaling for their migration to APCs. We found that the chemokine stromal-derived factor-1α (SDF-1α) triggered mitochondrial ATP production, rapid bursts of ATP release, and increased migration of primary human CD4+ T cells. This process depended on pannexin-1 ATP release channels and autocrine stimulation of P2X4 receptors. SDF-1α stimulation caused localized accumulation of mitochondria with P2X4 receptors near the front of cells, resulting in a feed-forward signaling mechanism that promotes cellular Ca2+ influx and sustains mitochondrial ATP synthesis at levels needed for pseudopod protrusion, T cell polarization, and cell migration. Inhibition of P2X4 receptors blocked the activation and migration of T cells in vitro. In a mouse lung transplant model, P2X4 receptor antagonist treatment prevented the recruitment of T cells into allograft tissue and the rejection of lung transplants. Our findings suggest that P2X4 receptors are therapeutic targets for immunomodulation in transplantation and inflammatory diseases.

Authors

Carola Ledderose, Kaifeng Liu, Yutaka Kondo, Christian J. Slubowski, Thomas Dertnig, Sara Denicoló, Mona Arbab, Johannes Hubner, Kirstin Konrad, Mahtab Fakhari, James A. Lederer, Simon C. Robson, Gary A. Visner, Wolfgang G. Junger

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Figure 5

P2X4 receptors regulate T cell polarization, pseudopod formation, and migration.

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P2X4 receptors regulate T cell polarization, pseudopod formation, and mi...
(A–C) Cell migration after silencing of P2X4 receptors in Jurkat cells or pharmacological P2X4 inhibition (5-BDBD, 10 μM) in CD4+ T lymphoblasts in the presence or absence of SDF-1α. (A) Representative images of 4 experiments; ×20 objective; scale bar, 10 μm (see also Supplemental Video 6). (B) Jurkat cells were treated with control or P2X4-targeting siRNA at the indicated concentrations, and migration speed and range (in 30 minutes) were analyzed after 48 hours. Data represent mean ± SEM of 60 cells derived from 3 experiments. (C) Jurkat cells were transfected with control or P2X4-targeting siRNA (10 nM) and migration was analyzed after 48 hours. Data represent mean ± SD of 3 (Jurkat cells) or 4 (T cells) separate experiments each comprising 40 cells. (D) Effect of P2X4 silencing or inhibition on the cell surface area of Jurkat cells, primary CD4+ T cells, and CD4+ T lymphoblasts stimulated or not with SDF-1α. Box plots show the median and the distribution of 262, 553, and 276 Jurkat cells, 297, 290, and 127 primary CD4+ T cells, 290 control lymphoblasts, and 127 lymphoblasts treated with 5-BDBD. Cells were analyzed in 4 separate experiments. (E) Migration of primary CD4+ T cells (no stimulation) or CD4+ T lymphoblasts treated or not with 5-BDBD was monitored by time-lapse microscopy. The number of pseudopodia formed by a particular cell during the 30-minute observation period was recorded. Box plots show the median and the distribution of 212 (no stimulation), 140 (control), and 82 (P2X4 inhibitor) analyzed cells derived from 5 (no stimulation) or 3 independent experiments. *P < 0.05 vs. control (Kruskal-Wallis test). #P < 0.05 (1-way ANOVA); TCR, T cell receptor.