The lack of suitable models currently hampers our understanding of how the tumor microenvironment responds to immunotherapy treatment. Here, we present a pro-tocol for ex vivo culture of patient... Show moreThe lack of suitable models currently hampers our understanding of how the tumor microenvironment responds to immunotherapy treatment. Here, we present a pro-tocol for ex vivo culture of patient-derived tumor fragments (PDTFs). We describe the steps for tumor collection, generation and cryopreservation of PDTFs, and their subsequent thawing. We detail culture of PDTFs and their preparation for analysis. This protocol preserves the tumor microenvironment's composition, architecture, and cellular interactions, which can be perturbed by ex vivo treatment. For complete details on the use and execution of this protocol, please refer to Voabil et al. (2021).1 Show less
Blomberg, O.S.; Spagnuolo, L.; Garner, H.; Voorwerk, L.; Isaeva, O.I.; Dyk, E. van; ... ; Kok, M. 2023
Immune checkpoint blockade (ICB) has heralded a new era in cancer therapy. Research into the mechanisms underlying response to ICB has predominantly focused on T cells; however, effective immune... Show moreImmune checkpoint blockade (ICB) has heralded a new era in cancer therapy. Research into the mechanisms underlying response to ICB has predominantly focused on T cells; however, effective immune responses require tightly regulated crosstalk between innate and adaptive immune cells. Here, we combine unbiased analysis of blood and tumors from metastatic breast cancer patients treated with ICB with mechanistic studies in mouse models of breast cancer. We observe an increase in systemic and intratumoral eosinophils in patients and mice responding to ICB treatment. Mechanistically, ICB increased IL-5 production by CD4(+) T cells, stimulating elevated eosinophil production from the bone marrow, leading to systemic eosinophil expansion. Additional induction of IL-33 by ICB-cisplatin combination or recombinant IL-33 promotes intratumoral eosinophil infiltration and eosinophil-dependent CD8(+) T cell activation to enhance ICB response. This work demonstrates the critical role of eosinophils in ICB response and provides proof-of-principle for eosinophil engagement to enhance ICB efficacy. Show less
Hummelink, K.; Noort, V. van der; Muller, M.; Schouten, R.D.; Lalezari, F.; Peters, D.; ... ; Thommen, D.S. 2022
Purpose: Durable clinical benefit to PD-1 blockade in non- small cell lung cancer (NSCLC) is currently limited to a small fraction of patients, underlining the need for predictive biomar-kers. We... Show morePurpose: Durable clinical benefit to PD-1 blockade in non- small cell lung cancer (NSCLC) is currently limited to a small fraction of patients, underlining the need for predictive biomar-kers. We recently identified a tumor-reactive tumor-infiltrating T lymphocyte (TIL) pool, termed PD-1T TILs, with predictive potential in NSCLC. Here, we examined PD-1T TILs as biomarker in NSCLC. Experimental Design: PD-1T TILs were digitally quantified in 120 baseline samples from advanced NSCLC patients treated with PD-1 blockade. Primary outcome was disease control (DC) at 6 months. Secondary outcomes were DC at 12 months and survival. Exploratory analyses addressed the impact of lesion-specific responses, tissue sample properties, and combination with other biomarkers on the predictive value of PD-1T TILs. Results: PD-1T TILs as a biomarker reached 77% sensitivity and 67% specificity at 6 months, and 93% and 65% at 12 months,respectively. Particularly, a patient group without clinical benefit was reliably identified, indicated by a high negative predictive value (NPV) (88% at 6 months, 98% at 12 months). High PD-1T TILs related to significantly longer progression-free (HR 0.39, 95% CI, 0.24-0.63, P < 0.0001) and overall survival (HR 0.46, 95% CI, 0.28-0.76, P < 0.01). Predictive performance was increased when lesion-specific responses and samples obtained immediately before treatment were assessed. Notably, the pre-dictive performance of PD-1T TILs was superior to PD-L1 and tertiary lymphoid structures in the same cohort. Conclusions: This study established PD-1T TILs as predictive biomarker for clinical benefit to PD-1 blockade in patients with advanced NSCLC. Most importantly, the high NPV demon-strates an accurate identification of a patient group without benefit. Show less
Neoadjuvant immunotherapy with anti-cytotoxic T lymphocyte-associated protein 4 (CTLA4) + anti-programmed cell death protein 1 (PD1) monoclonal antibodies has demonstrated remarkable pathological... Show moreNeoadjuvant immunotherapy with anti-cytotoxic T lymphocyte-associated protein 4 (CTLA4) + anti-programmed cell death protein 1 (PD1) monoclonal antibodies has demonstrated remarkable pathological responses and relapse-free survival in -80% of patients with clinically detectable stage III melanoma. However, about 20% of the treated patients do not respond. In pretreatment biopsies of patients with melanoma, we found that resistance to neoadjuvant CTLA4 + PD1 blockade was associated with a low CD4/interleukin-2 (IL-2) gene signature. Ex vivo, addition of IL-2 to CTLA4 + PD1 blockade induced T cell activation and deep immunological responses in anti-CTLA4 + anti-PD1-resistant human tumor specimens. In the 4T1.2 breast cancer mouse model of neoadjuvant immunotherapy, triple combination of anti-CTLA4 + anti-PD1 + IL-2 cured almost twice as many mice as compared with dual checkpoint inhibitor therapy. This improved efficacy was due to the expansion of tumor-specific CD8(+) T cells and improved proinflammatory cytokine polyfunctionality of both CD4(+) and CD8(+) T effector cells and regulatory T cells. Depletion studies suggested that CD4(+) T cells were critical for priming of CD8(+) T cell immunity against 4T1.2 and helped in the expansion of tumor-specific CD8(+) T cells early after neoadjuvant triple immunotherapy. Our results suggest that the addition of IL-2 can overcome resistance to neoadjuvant anti-CTLA4 +anti-PD1, providing the rationale for testing this combination as a neoadjuvant therapy in patients with early-stage cancer. Show less
Leun, A.M. van der; Hoekstra, M.E.; Reinalda, L.; Scheele, C.L.G.J.; Toebes, M.; Graaff, M.J. van de; ... ; Schumacher, T.N. 2021
The functional activity and differentiation potential of cells are determined by their interactions with surrounding cells. Approaches that allow unbiased characterization of cell states while at... Show moreThe functional activity and differentiation potential of cells are determined by their interactions with surrounding cells. Approaches that allow unbiased characterization of cell states while at the same time providing spatial information are of major value to assess this environmental influence. However, most current techniques are hampered by a tradeoff between spatial resolution and cell profiling depth. Here, we develop a photocage-based technology that allows isolation and in-depth analysis of live cells from regions of interest in complex ex vivo systems, including primary human tissues. The use of a highly sensitive 4-nitrophenyl(benzofuran) cage coupled to a set of nanobodies allows high-resolution photo-uncaging of different cell types in areas of interest. Single-cell RNA-sequencing of spatially defined CD8+ T cells is used to exemplify the feasibility of identifying location-dependent cell states. The technology described here provides a valuable tool for the analysis of spatially defined cells in diverse biological systems, including clinical samples. Show less
Voabil, P.; Bruijn, M. de; Roelofsen, L.M.; Hendriks, S.H.; Brokamp, S.; Braber, M. van den; ... ; Thommen, D.S. 2021
An ex vivo platform of patient-derived tumor fragments enables the assessment of intratumoral immune reactivation after PD-1 blockade that is predictive of clinical outcomes in patients with cancer... Show moreAn ex vivo platform of patient-derived tumor fragments enables the assessment of intratumoral immune reactivation after PD-1 blockade that is predictive of clinical outcomes in patients with cancer.Inhibitors of the PD-1-PD-L1 axis have been approved as therapy for many human cancers. In spite of the evidence for their widespread clinical activity, little is known about the immunological alterations that occur in human cancer tissue after PD-1 blockade. We developed and employed a patient-derived tumor fragment platform to dissect the early immunological response of human tumor tissue to ex vivo PD-1 blockade. We observed that the capacity of immune cells to be reactivated ex vivo was predictive of clinical response, and perturbation analyses identified tumor-resident T cells as a key component of this immunological response. In addition, through combined analysis of baseline properties and immune response capacity, we identified a new subgroup of infiltrated tumors that lacks the capacity to respond to PD-1 blockade. Finally, the baseline presence of tertiary lymphoid structures and their components correlated with the capacity of cancers to undergo intratumoral immune cell reactivation. Show less
Neoadjuvant chemo(radio)therapy is part of the established standard of care in cancer treatment; neoadjuvant application of immunotherapy, however, is only performed within recent trials.... Show moreNeoadjuvant chemo(radio)therapy is part of the established standard of care in cancer treatment; neoadjuvant application of immunotherapy, however, is only performed within recent trials. Combination of programmed cell death protein 1 and cytotoxic T lymphocyte antigen 4 blockade shows promising results with high pathologic response rates in the neoadjuvant setting and a very low relapse rate in the responding patients. In addition, neoadjuvant administration allows direct determination of treatment efficacy within the individual patient, and offers easy access to paired tumor material, both pretherapy and post-therapy, thus facilitates the rational development of new combinations driven by preclinical analyses. Patient-derived human tumor explant systems such as a recently developed human patient-derived tumor fragment platform can provide an additional tool to further rationalize the development of new treatment combinations. We will discuss neoadjuvant immunotherapy as a unique opportunity for rational trial design, the development of immune signatures for non-responding patients to steer clinical trial development, and the use of patient-derived ex vivo models to identify new personalized immunotherapy combinations. In this context, we propose the 'Lombard Street Approach', a back and forth approach of characterizing non-responders on neoadjuvant immunotherapy combinations, identifying promising new combinations for this group in the tumor fragment platform, and performing subsequently signature-driven small proof-of-concept combination trials. Repeating this approach with smaller and smaller groups of non-responders will step by step increase the percentage of patients benefiting from neoadjuvant immunotherapy in a rational and fast manner. Show less
