Blockade of interleukin 10 potentiates antitumour immune function in human colorectal cancer liver metastases

Abstract

ObjectiveProgrammed cell death protein 1 (PD-1) checkpoint inhibition and adoptive cellular therapy have had limited success in patients with microsatellite stable colorectal cancer liver metastases (CRLM). We sought to evaluate the effect of interleukin 10 (IL-10) blockade on endogenous T cell and chimeric antigen receptor T (CAR-T) cell antitumour function in CRLM slice cultures.DesignWe created organotypic slice cultures from human CRLM (n=38 patients’ tumours) and tested the antitumour effects of a neutralising antibody against IL-10 (αIL-10) both alone as treatment and in combination with exogenously administered carcinoembryonic antigen (CEA)-specific CAR-T cells. We evaluated slice cultures with single and multiplex immunohistochemistry, in situ hybridisation, single-cell RNA sequencing, reverse-phase protein arrays and time-lapse fluorescent microscopy.ResultsαIL-10 generated a 1.8-fold increase in T cell-mediated carcinoma cell death in human CRLM slice cultures. αIL-10 significantly increased proportions of CD8+ T cells without exhaustion transcription changes, and increased human leukocyte antigen - DR isotype (HLA-DR) expression of macrophages. The antitumour effects of αIL-10 were reversed by major histocompatibility complex class I or II (MHC-I or MHC-II) blockade, confirming the essential role of antigen presenting cells. Interrupting IL-10 signalling also rescued murine CAR-T cell proliferation and cytotoxicity from myeloid cell-mediated immunosuppression. In human CRLM slices, αIL-10 increased CEA-specific CAR-T cell activation and CAR-T cell-mediated cytotoxicity, with nearly 70% carcinoma cell apoptosis across multiple human tumours. Pretreatment with an IL-10 receptor blocking antibody also potentiated CAR-T function.ConclusionNeutralising the effects of IL-10 in human CRLM has therapeutic potential as a stand-alone treatment and to augment the function of adoptively transferred CAR-T cells.

Recent advances in organotypic tissue slice cultures for anticancer drug development

“…Organotypic tumor slice culture demonstrates the suitability to investigate the antitumor activity of small-molecule drug therapy (i.e., chemotherapy and molecularly targeted therapy) [24,25,27,41,47,49,[66][67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84], immunotherapy [27,31,85], radiotherapy [86][87][88], and adoptive cellular therapy [32], as summarized in Table 3 and discussed below.…”

“…Colorectal cancer liver metastasis IL-10 antibody plus CAR-T cell therapy 38 αIL-10 augments CAR-T cell activation and CAR-T cell-mediated cytotoxicity [32] Hepatic metastatic colorectal carcinoma Oxaliplatin, cetuximab, or pembrolizumab 9 Decrease in cell proliferation, with a heterogenous individual response to chemotherapy and targeted therapy [41] Breast cancer Cyclophosphamide, adriamycin plus 5-FU 15 Decrease in cell proliferation and induction of cell death [47] Glioblastoma Temozolomide 12 Decrease in cell proliferation and increase in cell loss and apoptosis, with a heterogenous individual response to chemotherapy [48] Gastric and esophagogastric junction cancer…”

“…This technique was initially utilized for the assessment of pharmacological efficacy around 1970 29 , 30 . The expediting evolvement of immunotherapy facilitates the application of this technique to evaluate the immune checkpoint blockade, and adoptive cellular therapy response on tumors in recent years 31 , 32 ( Figure 1 ). Organotypic tissue slice culture systems represent in vitro cultures of explants of patient- or animal-derived tumoral and normal tissues.…”

“…The tumor slice culture platform recently has been used to assess the efficacy of CAR-T cell therapy in solid tumors. Despite the low success of CAR-T cell therapy in human colorectal cancer liver metastases (CRLM), the interleukin-10 blockade has shown functions to enhance the antitumor activity of CAR-T cell therapy in human CRLM slices, as characterized by the increased CAR-T cell activation and CAR-T cell-caused cytotoxicity as well as amplified CAR-T cell proliferation 32 . Therefore, harnessing tumor slice culture models may broaden the clinical application of adoptive cellular therapy in solid tumors.…”

Recent advances in CAR-T cells therapy for colorectal cancer

“…IL-10 binds to its cognate receptor IL-10R to cause a wide range of immunosuppressive functions ( 79 , 80 ). Recent studies have shown that CAR-T cells combined with IL-10 monoclonal antibody (mAb) can partially alleviate bone marrow cell-mediated immunosuppression by blocking IL-10 signaling, while promoting CAR-T cells expansion and enhancing killing effect, thereby increasing anti-tumor function ( 81 ).…”