Adenosine Generated by Regulatory T Cells Induces CD8<sup>+</sup> T Cell Exhaustion in Gastric Cancer through A2aR Pathway

<div>Treg inhibits CD8<sup>+</sup> T cell function by promoting cAMP synthesis. Bead-purified peripheral single CD8<sup>+</sup> T cells (10<sup>5</sup> cells/well) were incubated in 6-well plates with Tregs at the ratio of 1 : 1. MRS1754 (A<sub>2b</sub>R antagonist; 200 nM) and ZM241385 (A<sub>2a</sub>R antagonist; 1 <i>μ</i>M) were added to CD8<sup>+</sup> T cells 30 min before adding Tregs. CD8<sup>+</sup> T cells without Treg coculture and treated with vehicle were set as control. After 5 days of culturing, cAMP (a), IFN-<i>γ</i> (b), perforin (c), and TNF-<i>α</i> (d) synthesized by CD8<sup>+</sup> T cells were detected by using ELISA kits according to the manufacturer’s instructions (<span class="nowrap"><svg height="10.7395pt" id="M33" style="vertical-align:-0.6370001pt" version="1.1" viewbox="-0.0498162 -10.1025 50.9184 10.7395" width="50.9184pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 376 444 381 422 380C389 338 368 319 321 288C323 345 329 372 349 422C339 442 322 461 305 470C289 461 271 442 262 422C281 372 287 345 290 288C243 319 222 338 189 380C167 381 142 376 125 366C125 347 133 322 145 304C198 296 225 288 275 262C225 236 198 227 145 220C133 201 125 177 126 158C141 148 167 143 189 144C222 186 243 205 290 236C288 179 282 152 262 102C272 82 289 63 306 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In ANOVA, all experiments are repeated at least five times.</div>

BioMed Research International

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Figure 4

Figure 4: Adenosine Generated by Regulatory T Cells Induces CD8<sup>+</sup> T Cell Exhaustion in Gastric Cancer through A2aR Pathway 

BioMed Research International

Adenosine Generated by Regulatory T Cells Induces CD8+ T Cell Exhaustion in Gastric Cancer through A2aR Pathway

Figure 4

Adenosine Generated by Regulatory T Cells Induces CD8⁺ T Cell Exhaustion in Gastric Cancer through A2aR Pathway