Exhaustion in tumor-infiltrating Mucosal-Associated Invariant T (MAIT) cells from colon cancer patients

© 2021. The Author(s)..

Mucosal-associated invariant T (MAIT) cells are unconventional T cells recognizing microbial metabolites, presented by the invariant MR1 protein. Upon activation, MAIT cells rapidly secrete cytokines and exert cytotoxic functions, and may thus be highly relevant also in tumor immunity. MAIT cells accumulate in colon tumors, but in contrast to other cytotoxic T cell subsets, their presence in tumors has been associated with worse patient outcome. Here we investigated if exhaustion may contribute to reduced anti-tumor immunity by MAIT cells. Freshly isolated lymphocytes from colon tumors, unaffected tissue and blood from the same patients were analyzed by flow cytometry to detect MAIT cells with effector functions that are relevant for tumor immunity, and their expression of inhibitory receptors and other exhaustion markers. Our studies show that MAIT cells with a PD-1highTim-3+CD39+ terminally exhausted phenotype and an increased proliferation accumulate in colon tumors. The exhausted MAIT cells have reduced polyfunctionality with regard to production of important anti-tumor effector molecules, and blocking antibodies to PD-1 partly improved activation of tumor-infiltrating MAIT cells in vitro. We conclude that the tumor microenvironment leads to exhaustion not only of conventional T cells, but also MAIT cells, and that checkpoint blockade therapy may be useful also to reinvigorate tumor-infiltrating MAIT cells.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:70

Enthalten in:

Cancer immunology, immunotherapy : CII - 70(2021), 12 vom: 22. Dez., Seite 3461-3475

Sprache:

Englisch

Beteiligte Personen:

Rodin, William [VerfasserIn]
Sundström, Patrik [VerfasserIn]
Ahlmanner, Filip [VerfasserIn]
Szeponik, Louis [VerfasserIn]
Zajt, Kamil Kajetan [VerfasserIn]
Wettergren, Yvonne [VerfasserIn]
Bexe Lindskog, Elinor [VerfasserIn]
Quiding Järbrink, Marianne [VerfasserIn]

Links:

Volltext

Themen:

Antigens, CD
Apyrase
Biomarkers
CD39
CD39 antigen
Colorectal cancer
Cytokines
EC 3.6.1.5
Exhaustion
Hepatitis A Virus Cellular Receptor 2
Journal Article
MAIT cell
PD-1
Programmed Cell Death 1 Receptor
Tim-3

Anmerkungen:

Date Completed 17.11.2021

Date Revised 18.02.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1007/s00262-021-02939-y

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM324400624