ILC2-derived IL-9 inhibits colorectal cancer progression by activating CD8+ T cells

Abstract

BackgroundType 2 innate lymphoid cells (ILC2s), characterized by secreting type 2 cytokines, regulate multiple immune responses. ILC2s are found in different tumor tissues and ILC2-derived interleukin (IL)-4, IL-5, and IL-13 act on the cells in tumor microenvironment to participate in tumor progression. ILC2s are abundant in colorectal cancer (CRC) tissue, but the role of ILC2s in CRC remains unclear. MethodsILC2s were sorted from the spleen using microbeads combined with flow cytometry and tumor infiltrating CD8 + T cells were isolated from tumor tissue by microbeads. Flow cytometry and immunofluorescence were used to detect the percentage of ILC2s and CD8 + T cells in the spleen and CRC tissue. Effects of IL-9 and IL-9-stimulated CD8 + T cells on CT26 cells were measured by proliferation, apoptosis, and migration assays in vitro. GEPIA was used to detect the ILC2s chemokines in CRC tissue and adjacent normal tissue. ResultsWe found that ILC2s were increased in CRC tissue compared with the adjacent normal tissue. In vitro experiments showed that IL-9 could activate CD8 + T cells to promote the death of CT26 cells. ILC2s were the main IL-9-secreting cells in CRC tissue as shown by flow cytometry analysis. In vivo experiments showed that neutralizing ILC2s promoted the tumor growth, while tumor inhibition occurred by intravenous injection of IL-9. ConclusionsOur results demonstrated that ILC2-derived IL-9 activated CD8 + T cells to promote anti-tumor effects in CRC.Th9 cells inhibit the development of melanoma and breast cancer by secreting 33]. In addition, Th9-derived IL-9 promotes the expansion of CD8 + T cells through IL-9 receptor (IL-9R) in CRC [34]. However, the main IL-9-producing cell subset in CRC remains unclear.Here we investigated the role of ILC2s and IL-9 in the CRC progression. The IL-9-producing cell subset in CRC tissue was also detected. We hypothesized that ILC2-derived IL-9 could exert an antitumor role in CRC. Materials And Methods Cell line and cell cultureThe murine CRC cell line CT26 was purchased from the American Type Culture Collection (Manassas, VA, USA). Cells were cultured in a humidified incubator with 5% CO2 at 37 °C. AnimalsFemale BALB/c mice (6-8 weeks, 18-22 g) were purchased from the Animal Center of Yangzhou University (Yangzhou, China) and the Animal Center of Jiangsu University (Zhenjiang, China). Mice were housed in cages and bred in pathogen-free rooms with a temperature of 23 °C ± 2 °C and relative humidity of 55%±10%. All animal experiments complied with the protocol of Jiangsu University Animal Ethics and Experimentation Committee.

Signaling Pathways Tuning Innate Lymphoid Cell Response to Hepatocellular Carcinoma

“…They are essential in the anti-helminth immune response but were shown to be detrimental in asthma and allergy contexts. The role of ILC2s in cancer is an emergent field of study with pro-tumor and anti-tumor actions depending on the context ( 27 , 28 ). Adult ILC3s are enriched in the intestine, rely on the expression of retinoic acid related orphan receptor (ROR)γt encoded by the RORc gene and are activated by IL-23 and IL-1β.…”

Effective Barriers: The Role of NKT Cells and Innate Lymphoid Cells in the Gut

“…The ILC2/IL-13 axis is thought to be involved in the establishment of a protumorigenic milieu, as ILC2-derived IL-13 promotes the recruitment and activity of myeloid derived suppressor cells (197,198); additionally, high expression of IL-13Ra was associated with poor prognosis (179). However, recent evidence supports a protective role of ILC2s in colon cancer in mice and humans, with ILC2 ablation or blockade resulting in increased tumor burden (199,200). In humans, high expression of an intratumor ILC2 gene signature was associated with increased survival, possibly due to IL-9mediated activation of CD8 T cells (200).…”

“…However, recent evidence supports a protective role of ILC2s in colon cancer in mice and humans, with ILC2 ablation or blockade resulting in increased tumor burden (199,200). In humans, high expression of an intratumor ILC2 gene signature was associated with increased survival, possibly due to IL-9mediated activation of CD8 T cells (200).…”

Innate Lymphoid Cells in Tissue Homeostasis and Disease Pathogenesis

“…In addition, in a lung metastatic melanoma model, ILC2s produce IL-5, thereby activating eosinophils and increasing their anti-tumor response ( Ikutani et al, 2012 ). Moreover, ILC2s produce IL-9, which is important to suppress metastasis of cancer cells, in tumor microenvironment ( Park et al, 2020 ; Wan et al, 2021 ).…”