Overcoming T cell dysfunction in acidic pH to enhance adoptive T cell transfer immunotherapy

Oncoimmunology. 2022 May 1;11(1):2070337. doi: 10.1080/2162402X.2022.2070337. eCollection 2022.


The high metabolic activity and insufficient perfusion of tumors leads to the acidification of the tumor microenvironment (TME) that may inhibit the antitumor T cell activity. We found that pharmacological inhibition of the acid loader chloride/bicarbonate anion exchanger 2 (Ae2), with 4,4'-diisothiocyanatostilbene-2,2'-disulfonicacid (DIDS) enhancedCD4+ andCD8+ T cell function upon TCR activation in vitro, especially under low pH conditions. In vivo, DIDS administration delayed B16OVA tumor growth in immunocompetent mice as monotherapy or when combined with adoptive T cell transfer of OVA-specificT cells. Notably, genetic Ae2 silencing in OVA-specificT cells improvedCD4+/CD8+ T cell function in vitro as well as their antitumor activity in vivo. Similarly, genetic modification of OVA-specificT cells to overexpress Hvcn1, a selectiveH+ outward current mediator that prevents cell acidification, significantly improved T cell function in vitro, even at low pH conditions. The adoptive transfer of OVA-specificT cells overexpressing Hvcn1 exerted a better antitumor activity in B16OVA tumor-bearingmice. Hvcn1 overexpression also improved the antitumor activity of CAR T cells specific for Glypican 3 (GPC3) in mice bearing PM299L-GPC3tumors. Our results suggest that preventing intracellular acidification by regulating the expression of acidifier ion channels such as Ae2 or alkalinizer channels like Hvcn1 in tumor-specificlymphocytes enhances their antitumor response by making them more resistant to the acidic TME.

Keywords: AE2; HVCN1; Lymphocytes; adoptive cell therapy; intracellular pH; tumor microenvironment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / metabolism
  • Animals
  • CD8-Positive T-Lymphocytes* / metabolism
  • Cell Line, Tumor
  • Hydrogen-Ion Concentration
  • Immunotherapy, Adoptive* / methods
  • Mice


  • 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid

Grants and funding

The work was supported by grants from Ministerio de Educación y Ciencia (SAF2016-78568-R to J.J.L. RTC-2017.6578-1 (Project AutoCAR), Ministerio de Ciencia e Innovación (PID2019-108989RB-I00, PLEC2021-008094 MCIN/AEI /10.13039/501100011033 (proyecto CARPanTu) and the European Union NextGenerationEU/PRTR), the European Union's Horizon 2020 research and innovation programme (Ner 945393, T2EVOLVE), Gobierno de Navarra (0011-1411-2019-000079 and 0011-1411-2019-000072 (Proyecto DESCARTHeS), Fundación Ramón Areces (to S.HS. and J.J.L) and Paula & Rodger Riney Foundation. TL is recipient of a Juan de la Cierva grant (IJCI-2017-34204).