Activating CD137 Signaling Promotes Sprouting Angiogenesis via Increased VEGFA Secretion and the VEGFR2/Akt/eNOS Pathway

<div>CD137-enhanced aortic sprouting and outspreading through the VEGFR2/Akt/eNOS pathway. (a) The sprouting of aortic rings under the CD137 activation or/and inhibition of VEGFR2 with XL184 (cabozantinib). (b) Number of sprouts per ring was quantified by Image-Pro Plus 8.0, <span class="nowrap"><svg height="12.7373pt" id="M37" style="vertical-align:-3.429399pt" version="1.1" viewbox="-0.0498162 -9.3079 92.068 12.7373" width="92.068pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M319 325C317 349 306 409 297 431C277 440 250 449 209 449C117 449 57 389 57 319C57 243 122 209 182 182C232 159 261 135 261 91C261 48 227 21 190 21C130 21 85 79 68 145L41 140C41 104 51 36 58 22C75 7 121 -12 172 -12C252 -12 337 35 337 126C337 195 286 231 210 262C166 281 126 304 126 348C126 388 152 417 191 417C240 417 274 378 294 318L319 325Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.875,0)"><path d="M390 111C344 68 312 56 269 56C212 56 118 102 118 241C118 346 175 401 241 401C277 401 312 388 342 360C350 352 355 349 361 349C372 349 394 371 394 392C394 403 391 411 378 422C362 436 329 449 288 449H287C250 449 190 432 138 392C71 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Mediators of Inflammation

fig5

Figure 5

Figure 5: Activating CD137 Signaling Promotes Sprouting Angiogenesis via Increased VEGFA Secretion and the VEGFR2/Akt/eNOS Pathway 