Expression of CD39 is associated with T cell exhaustion in ovarian cancer and its blockade reverts T cell dysfunction

ABSTRACT

Immune exhaustion is a hallmark of ovarian cancer. Using multiparametric flow cytometry, the study aimed to analyze protein expression of novel immunological targets on CD3⁺ T cells isolated from the peripheral blood (n = 20), malignant ascites (n = 16), and tumor tissue (n = 6) of patients with ovarian cancer (OVCA). The study revealed an increased proportion of effector memory CD8⁺ T cells in OVCA tissue and malignant ascites. An OVCA-characteristic PD-1^high CD8⁺ T cell population was detected, which differed from PD-1^lowCD8⁺ T cells by increased co-expression of TIGIT, CD39, and HLA-DR. In addition, these OVCA-characteristic CD8⁺ T cells showed reduced expression of the transcription factor TCF-1, which may also indicate reduced effector function and memory formation. On the contrary, the transcription factor TOX, which significantly regulates terminal T cell-exhaustion, was found more frequently in these cells. Further protein and gene analysis showed that CD39 and CD73 were also expressed on OVCA tumor cells isolated from solid tumors (n = 14) and malignant ascites (n = 9). In the latter compartment, CD39 and CD73 were also associated with the expression of the “don’t eat me” molecule CD24 on tumor cells. Additionally, ascites-derived CD24⁺EpCAM⁺ tumor cells showed a higher frequency of CD39⁺ or CD73⁺ cells. Furthermore, CD39 expression was associated with unfavorable clinical parameters. Expression of CD39 on T cells was upregulated through CD3/CD28 stimulation and its blockade by a newly developed nanobody construct resulted in increased proliferation (eFluor), activation (CD25 and CD134), and production of cytotoxic cytokines (IFN-γ, TNF-α, and granzyme-B) of CD8⁺ T cells.

KEYWORDS:

• Blockade
• CD39
• CD73
• ovarian cancer
• TIGIT
• PD-1
• malignant ascites
• Nanobody

Abbreviations

PD-1: programmed cell death protein-1; ITIM: immunoreceptor tyrosine – based inhibitory motif; TIGIT: T-cell immunoglobulin and immunoreceptor tyrosine – based inhibitory motif (ITIM) domain; OVCA: ovarian cancer; TIM-3: T-cell immunoglobulin and mucin-domain containing-3; CD39: ectonucleoside triphosphate diphosphohydrolase 1; CD73: ecto-5′-nucleotidase; ATP: adenosine triphosphate; HLA-DR: human leukocyte antigens – DR isotype; MHC: major histocompatibility complex; IFN-γ: interferon gamma; TOX: thymocyte selection-associated high mobility group box; TCF-1: transcription factor T cell factor 1; PBL: Peripheral blood lymphocytes; MAL: malignant ascites lymphocytes; TIL: tumor infiltrating lymphocytes; HD: healthy donor; PBS: phosphate-buffered saline; MFC: multiparameter flow cytometry; FACS: fluorescence activated cell sorting; FcR: Fc receptor; FBS: fetal bovine serum; PBMC: peripheral blood mononuclear cells; IL-2: interleukin 2; CD4_con: conventional CD4⁺; CD4_reg: regulatory CD4⁺ NA: naïve; CM: central memory; EM: effector memory; TEMRA: terminally differentiated effector memory; SPICE: Simplified Presentation of Incredibly Complex Evaluations; EpCAM: epithelial cell adhesion molecule; tSNE: t-distributed stochastic neighbor embedding; MFI: median fluorescence intensity; TNF-α: tumor necrosis factor alpha; NK: natural killer

Acknowledgment

We thank all our patients for their trust, understanding, and willingness to provide their blood, ascites, and tumor tissue samples for our research. We would like to thank our FACS core facility. And we thank Sabine Wuttke for her contribution to the creation of our graphical abstract that enhances the communication of our findings. We acknowledge financial support from the Open Access Publication Fund of UKE - University Medical Center Hamburg-Eppendorf.

Competing interests

BC: Personal fees from AOK Germany, med update, Roche Pharma, Astra Zeneca, Bayer Healthcare, BioNTech, Bristol Myers Squipp, Jansen Cilag, Merck Serono, Oncology Drug Consult CRO, Sanofi Aventis; Invited speaker by AOK Germany, med update, Roche Pharma; Advisory board by Astra Zeneca, Bayer Healthcare, BioNTech, Bristol Myers Squipp, Jansen Cilag, Merck Serono, Oncology Drug Consult CRO, Sanofi Aventis. SB: Consulting and advisory board for Astra Zeneca, Roche, MSD, EISAI, GSK, Olympus; honoraria for presentations from Astra Zeneca, Roche, GSK, MSD, Clovis; travel grants Astra Zeneca, Roche, GSK; support for research from Roche, MSD, GSK, Astra Zeneca. WJ: patent for Amgen issued. FW: personal fees and non-financial support from AbbVie; grants, personal fees, and non-financial support from Amgen and Pfizer; and personal fees from Jazz Pharmaceuticals, Celgene, Morphosys, Ariad/Incyte, stem line therapeutics Daiichi Sankyo, and Servier outside the submitted work; in addition, FW has a patent for Amgen issued; and support for medical writing: Amgen, Pfizer, AbbVie. BF: Travel grants Daiichi Sankyo, Servier, Novartis; advisory board by Jazz. GmbH, Daiichi Sankyo. The remaining authors declare that they have no conflict of interest.

Availability of data and material

The datasets used and/or analyzed during the current study are available from the corresponding authors on reasonable request ([email protected]).

Contributions

BF, OFL, FW, and WJ designed the research study, WM, SE, WP, DY, HL and BF performed the experiments and analyzed the data. OFL analyzed the RNAseq data, WM and FB wrote the manuscript. KNF and MS provided the nanobodies used in the project. SB, BC, FW and WJ monitored the data analyses and interpretation and reviewed the manuscript. All authors read and approved the final manuscript.

Ethics approval and consent to participate

The study was approved by the local ethics board of the Ärztekammer Hamburg (#200814 and PV6012–4312-BO-ff). Informed written consent was obtained from all patients.

Disclosure statement

The authors have no conflicts of interest to disclose.

Supplementary materials

Supplemental data for this article can be accessed online at https://doi.org/10.1080/2162402X.2024.2346359

Additional information

Funding

The study was funded by the BMBF (N/A to WJ, OFL and ST), by the Mildred Scheel Nachwuchszentrum (HaTriCS program, German Cancer Aid, N/A to BF). WM was financially supported by the Else Kröner-Fresenius-Stiftung iPRIME Scholarship (2021_EKPK.10), UKE, Hamburg. The RNAseq analysis of the ovarian cancer cohort from the gynecology department at the UKE was funded by the Wilhelm Sander-Stiftung.