bims-tuinly 2025-08-17 papers

bims-tuinly

Biomed News

on Tumor-infiltrating lymphocytes therapy

Issue of 2025–08–17
eleven papers selected by
Pierpaolo Ginefra, Ludwig Institute for Cancer Research

Prognostic value of PD-L1, tumor-infiltrating lymphocytes, and CD117 in vulvovaginal melanoma.
Lymphodepletion, tumor-infiltrating lymphocytes, and high versus low dose IL-2 followed by pembrolizumab in patients with metastatic melanoma.
Feasibility of Manufacturing and Antitumor Activity of TIL for Advanced Endometrial Cancers.
Immunotherapy with lymphocytes derived from banked tumor tissue in two refractory NSCLC patients with leptomeningeal metastases: a report of two cases.
Are [18F]FDG PET/CT imaging and cell blood count-derived biomarkers robust non-invasive surrogates for tumor-infiltrating lymphocytes in early-stage breast cancer?
Cancer-Associated Fibroblasts: Immunosuppressive Crosstalk with Tumor-Infiltrating Immune Cells and Implications for Therapeutic Resistance.
High oxidative phosphorylation represented by UQCRFS1 marks CD8 + tumor-infiltrating lymphocytes exhaustion in diffuse large B-cell lymphoma.
Exploiting TCR Repertoire Analysis to Select Therapeutic TCRs for Cancer Immunotherapy.
Predictive role of tumor-infiltrating lymphocytes and immune phenotype for pembrolizumab in relapsed or refractory thymic carcinoma.
Combination immunotherapy targeting LAG-3, PD-1 and STING suppresses hepatocellular carcinoma as monitored by LAG-3 targeted PET imaging.
SAR-444245, an engineered not-alpha IL-2 leveraging synthetic biology, modulates critical components of the immune system for durable anti-tumoral activity.

Int J Gynecol Cancer. 2025 Jun 29. pii: S1048-891X(25)01116-8. [Epub ahead of print]35(9): 101996

Prognostic value of PD-L1, tumor-infiltrating lymphocytes, and CD117 in vulvovaginal melanoma.

Chiau-Sheng Jang, I-Chieh Chuang.

   OBJECTIVE: Vulvovaginal melanoma represents a rare and aggressive melanoma subtype with distinct mutation patterns, such as a higher frequency of KIT (CD117) mutations, and is associated with poor clinical outcomes. This study investigated the prognostic implications of PD-L1 expression, tumor-infiltrating lymphocytes (TILs), and CD117 expression in patients with vulvovaginal melanoma.
METHODS: A retrospective analysis was conducted on histologically confirmed vulvovaginal melanoma cases diagnosed between January 2010 and December 2020. Immunohistochemical evaluation was performed to assess PD-L1 and CD117 expression, while TIL density was graded using published guidelines. Associations between PD-L1 expression and key clinicopathological features were also evaluated. The primary outcome was disease-specific survival, defined as the interval from diagnosis to death specifically attributable to vulvovaginal melanoma, analyzed using Kaplan-Meier estimates and Cox regression models.
RESULTS: Among 47 patients, 70% presented with advanced-stage disease (stage III-IV). PD-L1 expression was detected in 22 patients (47%), and brisk TIL infiltration was observed in 12 patients (26%). PD-L1 positivity correlated with advanced disease stage (p = .002), non-brisk/absent TILs (p = .003), and lymphovascular invasion (p = .047). Kaplan-Meier analysis demonstrated significantly better disease-specific survival in PD-L1-negative tumors (3-year disease-specific survival: 48% vs 18%, p = .008) and in tumors with brisk TIL infiltration (3-year disease-specific survival: 67% vs 21%, p = .003). Combined stratification identified PD-L1-negative/brisk TIL tumors as the most favorable subgroup, while PD-L1-positive/non-brisk/absent TIL tumors exhibited the poorest prognosis (p < .001). In multivariate analysis, PD-L1 expression (HR 1.68, 95% CI 1.10 to 2.55, p = .015), TIL status (HR 0.62, 95% CI 0.43 to 0.89, p = .012), and disease stage (HR 1.85, 95% CI 1.22 to 2.81, p = .004) remained independent prognostic factors. Additionally, CD117 positivity was observed in 30% of tumors (n = 14), although its prognostic significance was not retained in multivariate analysis.
CONCLUSIONS: The study establishes PD-L1 expression and TIL density as independent prognostic factors in vulvovaginal melanoma, suggesting their potential utility for risk stratification and therapeutic decision-making.

Keywords:  Immunohistochemistry; Prognosis; Programmed Cell Death 1 Ligand 1; Tumor-Infiltrating Lymphocytes; Vulvovaginal Melanoma

DOI:  https://doi.org/10.1016/j.ijgc.2025.101996
Oncoimmunology. 2025 Dec;14(1): 2546402

Lymphodepletion, tumor-infiltrating lymphocytes, and high versus low dose IL-2 followed by pembrolizumab in patients with metastatic melanoma.

Merve Hasanov, Simin Kiany, Marie-Andrée Forget, Roland Bassett, Michael A Davies, Adi Diab, Jeffrey E Gershenwald, Isabella C Glitza, Jeffrey E Lee, Anthony Lucci, Jennifer L McQuade, Sapna P Patel, Merrick I Ross, Hussein A Tawbi, Jennifer A Wargo, Michael K Wong, Chantale Bernatchez, Patrick Hwu, Cara Haymaker, Rodabe N Amaria.

  This study evaluated the efficacy and safety of unengineered tumor-infiltrating lymphocytes (TILs) combined with pembrolizumab and either high (HD, Arm-1) or low (LD, Arm-2) doses of IL-2 in patients with metastatic melanoma (MM). Patients were lymphodepleted with cyclophosphamide and fludarabine, followed by TIL infusion and IL-2 (Arm-1: 720,000 IU/kg IV q 8 hrs up to 15 doses; Arm-2: 2 million IU SC for 14 days). Patients received pembrolizumab 200 mg IV starting 21 days post-TIL infusion, and every 3 weeks for up to 2 years. The primary endpoint was overall response rate (ORR) per RECIST 1.1. Blood samples were collected for longitudinal flow cytometry and cytokine analysis. In Arm-1 (n = 7), one patient had a partial response (PR) for 10 months, two had stable disease (SD), three had progressive disease (PD), and one was not evaluable (NE). In Arm-2 (n = 7), one patient had an ongoing PR for over 76 months, one had SD, and five had PD. The toxicity profiles were comparable; however, patients in Arm-2 had lower grade 3 febrile neutropenia (57% vs. 71%) and shorter hospitalization (median 16 days vs. 18 days). No correlation was observed between TIL phenotype and clinical response, although PR patients received high numbers of TIL with a high CD8+/CD4+ T cell ratio. IL-2 dose did not affect the frequency, phenotype, or proliferation of circulating T cell subsets, and anti-PD-1 did not boost T-cell proliferation. No significant differences were observed between IL-2 doses, suggesting low-dose IL-2 as an alternative to high-dose IL-2 after TIL administration.

Keywords:  Tumor-infiltrating lymphocytes; adoptive cell therapy; anti-PD-1; checkpoint blockade; immune profiling; interleukin 2

DOI:  https://doi.org/10.1080/2162402X.2025.2546402
Int J Mol Sci. 2025 Jul 24. pii: 7151. [Epub ahead of print]26(15):

Feasibility of Manufacturing and Antitumor Activity of TIL for Advanced Endometrial Cancers.

Yongliang Zhang, Kathleen N Moore, Amir A Jazaeri, Judy Fang, Ilabahen Patel, Andrew Yuhas, Patrick Innamarato, Nathan Gilbert, Joseph W Dean, Behzad Damirchi, Joe Yglesias, Rongsu Qi, Michelle R Simpson-Abelson, Erwin Cammaart, Sean R R Hall, Hequn Yin.

  Lifileucel, a tumor-infiltrating lymphocyte (TIL) cell therapy approved for advanced melanoma, demonstrates promise for treating other solid tumors, including endometrial cancer (EC). The current study evaluates the feasibility of manufacturing TILs from EC tumors using Iovance's proprietary 22-day Gen2 manufacturing process. Key parameters, including TIL yield, viability, immune phenotype, T-cell receptor clonality, and cytotoxic activity, were assessed. Of the 11 EC tumor samples processed at research scale, 10 (91%) successfully generated >1 × 109 viable TIL cells, with a median yield of 1.1 × 1010 cells and a median viability of 82.8%. Of the four EC tumor samples processed at full scale, all achieved the pre-specified TVC and viability targets. Putative tumor-reactive T-cell clones were maintained throughout the manufacturing process. Functional reactivity was evidenced by the upregulation of 4-1BB in CD8+ T cells, OX40 in CD4+ T cells, and increased production of IFN-γ and TNF-α upon autologous tumor stimulation. Furthermore, antitumor activity was confirmed using an in vitro autologous tumor organoid killing assay. These findings demonstrate the feasibility of ex vivo TIL expansion from EC tumors. This study provides a rationale for the initiation of the phase II clinical trial IOV-END-201 (NCT06481592) to evaluate lifileucel in patients with advanced EC.

Keywords:  immunotherapy; mismatch repair; tumor-infiltrating lymphocytes; uterine neoplasms

DOI:  https://doi.org/10.3390/ijms26157151
Transl Lung Cancer Res. 2025 Jul 31. 14(7): 2880-2890

Immunotherapy with lymphocytes derived from banked tumor tissue in two refractory NSCLC patients with leptomeningeal metastases: a report of two cases.

Ai-Hong Zheng, Chong Yu, Yong-Rui Su, Min Peng, Jian-Yuan Chen, Fu-Wei Wang, Xiu-Ming Zhu, Pei-Yuan Yan, Hai-Tao Wang, Jian Shen, Wei-Jun Chen, Qiang Li, Yuan Chen, Yi Chen, Yin-Shuang Wang, Hang-Yu Gu, Zhuo-Nan Meng, Jing-Wen Zhao, Wan-Mao Ni, Tian-Hua Wang, Sheng-Lian Wu, Min Li, Zheng Wang, Ai-Ping Cheng, Xiao-Xian Huang, Zi-Yan Yang, Jia-Hong Jiang, Qun-Jiang Wang, Jing Qu, Shi-Tai Zhang, Ke-Ke Shi, Hua-Xin Zhang, Da-Hong Zhang, Guo-Qing Wu.

   Background: Cancer patients relapsing with leptomeningeal metastases (LM) but without extracranial lesions are usually unsuitable for cellular immunotherapy with tumor-infiltrating lymphocytes (TILs) owing to lack of tumor tissue. TILs generated from heavily pretreated patients, especially those with non-melanoma cancer often have anergic effects and are less toxic to tumors, limiting the antitumor efficacy of lymphocyte-based therapy. Whether using autologous tumor tissue banked in advance addresses the dilemma has not been explored.
Case Description: We present two cases of non-small cell lung cancer (NSCLC) who relapsed with LM but without extracranial lesions for whom TIL therapy is otherwise unsuitable. Using autologous tumor tissue banked in advance when they initially underwent tumor resection, we successfully generated therapeutic TILs of which the enhancer of zeste homolog 2 (EZH2) activity was further inhibited in regulatory T cells (Tregs). One case received autologous TILs prepared from a cryopreserved pathological complete response lesion and achieved a complete remission of LM that was ongoing till the preparation of this manuscript. The other case was treated with autologous TILs derived from a cryopreserved treatment-naïve tumor tissue and only achieved a transient response manifested by short-term decrease of circulating tumor deoxyribonucleic acid and serum carcinoembryonic antigen.
Conclusions: TILs generated from treatment-responsive lesions and underwent inhibition of EZH2 activity in Tregs have high antitumor efficacy and the banking in advance of treatment-responsive tumor tissue potentially provides a safe and effective adoptive cell therapy (ACT) with TILs for refractory NSCLC patients with LM for whom TIL therapy is otherwise unsuitable.

Keywords:  Tumor-infiltrating lymphocyte; adoptive cell therapy (ACT); case report; leptomeningeal metastases; non-small cell lung cancer (NSCLC)

DOI:  https://doi.org/10.21037/tlcr-2025-274
Ann Nucl Med. 2025 Aug 12.

Are [18F]FDG PET/CT imaging and cell blood count-derived biomarkers robust non-invasive surrogates for tumor-infiltrating lymphocytes in early-stage breast cancer?

Romain-David Seban, Louis Rebaud, Lounes Djerroudi, Anne Vincent-Salomon, Francois-Clement Bidard, Laurence Champion, Irene Buvat.

   OBJECTIVE: Tumor-infiltrating lymphocytes (TILs) are key immune biomarkers associated with prognosis and treatment response in early-stage breast cancer (BC), particularly in the triple-negative subtype. This study aimed to evaluate whether [18F]FDG PET/CT imaging and routine cell blood count (CBC)-derived biomarkers can serve as non-invasive surrogates for TILs, using machine-learning models.
MATERIAL AND METHODS: We retrospectively analyzed 358 patients with biopsy-proven early-stage invasive BC who underwent pre-treatment [18F]FDG PET/CT imaging. PET-derived biomarkers were extracted from the primary tumor, lymph nodes, and lymphoid organs (spleen and bone marrow). CBC-derived biomarkers included neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). TILs were assessed histologically and categorized as low (0-10%), intermediate (11-59%), or high (≥ 60%). Correlations were assessed using Spearman's rank coefficient, and classification and regression models were built using several machine-learning algorithms.
RESULTS: Tumor SUVmax and tumor SUVmean showed the highest correlation with TIL levels (ρ = 0.29 and 0.30 respectively, p < 0.001 for both), but overall associations between TILs and PET or CBC-derived biomarkers were weak. No CBC-derived biomarker showed significant correlation or discriminative performance. Machine-learning models failed to predict TIL levels with satisfactory accuracy (maximum balanced accuracy = 0.66). Lymphoid organ metrics (SLR, BLR) and CBC-derived parameters did not significantly enhance predictive value.
DISCUSSION: In this study, neither [18F]FDG PET/CT nor routine CBC-derived biomarkers reliably predict TILs levels in early-stage BC. This observation was made in presence of potential scanner-related variability and for a restricted set of usual PET metrics. Future models should incorporate more targeted imaging approaches, such as immunoPET, to non-invasively assess immune infiltration with higher specificity and improve personalized treatment strategies.

Keywords:  Breast cancer; Machine Learning; Tumor Microenvironment; Tumor-infiltrating lymphocytes; [18]FDG PET/CT

DOI:  https://doi.org/10.1007/s12149-025-02098-5
Cancers (Basel). 2025 Jul 28. pii: 2484. [Epub ahead of print]17(15):

Cancer-Associated Fibroblasts: Immunosuppressive Crosstalk with Tumor-Infiltrating Immune Cells and Implications for Therapeutic Resistance.

Jogendra Singh Pawar, Md Abdus Salam, Md Shalman Uddin Dipto, Md Yusuf Al-Amin, Moushumi Tabassoom Salam, Sagnik Sengupta, Smita Kumari, Lohitha Gujjari, Ganesh Yadagiri.

  Cancer is no longer considered as an isolated event. Rather, it occurs because of a complex biological drive orchestrating different cell types, growth factors, cytokines, and signaling pathways within the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are the most populous stromal cells within the complex ecosystem of TME, with significant heterogeneity and plasticity in origin and functional phenotypes. Very enigmatic cells, CAFs determine the progress and outcomes of tumors through extensive reciprocal signaling with different tumors infiltrating immune cells in the TME. In their biological drive, CAFs release numerous chemical mediators and utilize various signaling pathways to recruit and modulate tumor-infiltrating immune cells. The CAF-induced secretome and exosomes render immune cells ineffective for their antitumor activities. Moreover, by upregulating immune inhibitory checkpoints, CAFs create an immunosuppressive TME that impedes the susceptibility of tumor cells to tumor-infiltrating lymphocytes (TILs). Further, by depositing and remodeling extracellular matrix (ECM), CAFs reshape the TME, which enhances tumor growth, invasion, metastasis, and chemoresistance. Understanding of CAF biology and its crosstalk with tumor-infiltrating immune cells is crucial not only to gain insight in tumorigenesis but to optimize the potential of novel targeted immunotherapies for cancers. The complex relationships between CAFs and tumor-infiltrating immune cells remain unclear and need further study. Herein, in this narrative review we have focused on updates of CAF biology and its interactions with tumor-infiltrating immune cells in generating immunosuppressive TME and resistance to cell death.

Keywords:  CAF-induced immunosuppression; biological crosstalk; cancer-associated fibroblasts; tumor cell resistance; tumor microenvironment; tumor-infiltrating immune cells

DOI:  https://doi.org/10.3390/cancers17152484
Biol Direct. 2025 Aug 13. 20(1): 92

High oxidative phosphorylation represented by UQCRFS1 marks CD8 + tumor-infiltrating lymphocytes exhaustion in diffuse large B-cell lymphoma.

Yiming Yang, Yaqi Shu, Zujun Qin, Yi Zeng, Kexin Chen, Xin Liu, Shunhai Jian, Qiqi Zhu.

   BACKGROUND: Metabolic alterations are closely associated with the exhaustion and immune deficiency of CD8+ tumor-infiltrating lymphocytes (TILs), while little is known about diffuse large B-cell lymphoma (DLBCL). This study aimed to elucidate the significance of the metabolic alterations in exhausted CD8+TILs and its underlying regulatory mechanism in DLBCL.
METHODS: The metabolic alterations in exhausted CD8+TILs in DLBCL were evaluated through single-cell RNA sequencing (scRNA-seq). The crucial metabolic pathway and its significance in the biological function of exhausted CD8+TILs were investigated by scRNA-seq and RNA sequencing. The marker gene in crucial metabolic pathway, and its correlations between exhaustion status, the tumor microenvironment (TME) composition, clinicopathological characteristics, prognosis, and immune checkpoint blockade (ICB) therapy efficacy were evaluated by scRNA-seq, RNA sequencing, immunohistochemistry, and RT-qPCR. Furthermore, the underlying regulatory mechanism involved in the metabolic alteration related to CD8+TILs exhaustion was explored through scRNA-seq, RNA sequencing, and somatic mutation analysis.
RESULTS: Our study illustrated the metabolic heterogeneity in CD8+TILs, and demonstrated that oxidative phosphorylation (OXPHOS) was the crucial pathway in CD8+TILs exhaustion. The high OXPHOS activity indicated the immune deficiency in exhausted CD8+TILs, and UQCRFS1 was identified as a marker gene. High UQCRFS1 indicated the immunosuppressive TME, severe clinicopathological characteristics, including activated B-cell-like subtype, high IPI and PS score, advanced stage, dismal prognosis, and resistance to ICB therapy. Furthermore, MYC-related signaling and P2RY8 mutation in DLBCL may regulate the UQCRFS1 expression in exhausted CD8+TILs.
CONCLUSIONS: Our study highlights the importance of OXPHOS activity in CD8+TILs exhaustion and suggests its possible regulatory mechanism, which is feasible in clinical evaluation and beneficial for novel immunotherapeutic approaches in DLBCL.

Keywords:  CD8+tumor-infiltrating lymphocytes; Clinicopathological analysis; Diffuse large B-cell lymphoma; Exhaustion; Immunotherapy; Metabolism; Oxidative phosphorylation; Prognosis

DOI:  https://doi.org/10.1186/s13062-025-00684-1
Cells. 2025 Aug 07. pii: 1223. [Epub ahead of print]14(15):

Exploiting TCR Repertoire Analysis to Select Therapeutic TCRs for Cancer Immunotherapy.

Ursule M Demaël, Thunchanok Rirkkrai, Fatma Zehra Okus, Andreas Tiffeau-Mayer, Hans J Stauss.

  Over the past decade, numerous innovative immunotherapy strategies have transformed the treatment of cancer and improved the survival of patients unresponsive to conventional chemotherapy and radiation therapy. Immune checkpoint inhibition approaches aim to block negative regulatory pathways that limit the function of endogenous T cells, while adoptive cell therapy produces therapeutic T cells with high functionality and defined cancer specificity. While CAR engineering successfully targets cancer surface antigens, TCR engineering enables targeting of the entire cancer proteome, including mutated neo-antigens. To date, TCR engineering strategies have focused on the identification of target cancer antigens recognised by well-characterised therapeutic TCRs. In this review, we explore whether antigen-focused approaches could be complemented by TCR-focused approaches, whereby information of the TCR repertoire of individual patients provides the basis for selecting TCRs to engineer autologous T cells for adoptive cell therapy. We discuss how TCR clonality profiles, distribution in T cell subsets, and bioinformatic screening against continuously improving TCR databases can guide the selection of TCRs for therapeutic application. We further outline in vitro approaches to prioritise TCR candidates to confirm cancer reactivity and exclude recognition of healthy autologous cells, which could provide validation for their therapeutic use even when the target antigen remains unknown.

Keywords:  T cell receptor; TCR repertoire; TCR sequencing; TCR-T cells; cancer immunotherapy; cell therapy; clonality; meta-clonotype; tumour infiltrating lymphocytes

DOI:  https://doi.org/10.3390/cells14151223
J Thorac Dis. 2025 Jul 31. 17(7): 4409-4419

Predictive role of tumor-infiltrating lymphocytes and immune phenotype for pembrolizumab in relapsed or refractory thymic carcinoma.

Dong Hyun Kim, Yoojoo Lim, Sanghoon Song, Chan-Young Ock, Jeonghwan Youk, Miso Kim, Tae Min Kim, Dong-Wan Kim, Hak Jae Kim, Jiwon Koh, Kyeong Cheon Jung, Kwon Joong Na, Chang Hyun Kang, Bhumsuk Keam.

   Background: Pembrolizumab is a promising treatment option for platinum-failed thymic carcinoma; however, the lack of established predictive biomarkers remains a challenge. Therefore, this study aimed to assess the predictive value of artificial intelligence (AI)-powered tumor-infiltrating lymphocyte (TIL) analysis of pembrolizumab for thymic carcinoma.
Methods: Patients with platinum-failed, advanced thymic carcinoma treated with pembrolizumab between January 2016 and December 2021 were included. Hematoxylin and eosin-stained sections from the samples closest to the time before pembrolizumab treatment were analyzed using an AI-powered TIL analyzer. Intratumoral TIL (iTILs) and stromal TIL (sTILs) were quantified, and their immune phenotypes (IP) were identified.
Results: In total, 10 patients were included in this study. The best response was complete response in 1 patient (10%) and partial response in 1 patient (10%). The median progression-free survival (PFS) was 5.0 months. Patients with higher iTIL (>27.23/mm2) exhibited longer PFS (median, 9.5 vs. 1.5 months, P=0.03) and overall survival (OS) (median, not determined vs. 4 months, P=0.03). Patients with higher sTIL (>252.54/mm2) exhibited longer PFS (median, 10 vs. 1 month, P=0.006) and OS (median, not determined vs. 9 months, P=0.01). Patients with inflamed IP exhibited longer PFS than those with non-inflamed IP (median, 10 vs. 3 months, P=0.046).
Conclusions: Increased infiltration of both iTIL and sTIL is associated with longer PFS and OS. Additionally, an inflamed IP is associated with longer PFS. Thus, TIL density and IP may be promising predictive biomarkers for pembrolizumab in patients with platinum-failed thymic carcinoma.

Keywords:  Thymic carcinoma; artificial intelligence (AI); immune phenotype; pembrolizumab; tumor-infiltrating lymphocyte (TIL)

DOI:  https://doi.org/10.21037/jtd-2025-526
Biomark Res. 2025 Aug 12. 13(1): 102

Combination immunotherapy targeting LAG-3, PD-1 and STING suppresses hepatocellular carcinoma as monitored by LAG-3 targeted PET imaging.

Zhen Quan, Yu Gao, Bo Sun, Yiwan Guo, Ziwei Jin, Na Hao, Dawei Jiang, Chuansheng Zheng, Xin Li, Quan Chen.

   BACKGROUND: The low response rate of anti-PD-1 monoclonal antibodies (mAbs) in hepatocellular carcinoma (HCC) requires the development of combination immunotherapy strategies to improve their efficacy. This study aimed to use LAG-3-targeted PET imaging to monitor the efficacy of anti-PD-1 mAb, a stimulator of interferon genes (STING) agonist, and anti-LAG-3 mAb, both individually and in combination. Furthermore, we evaluated the potential of a triple immunotherapy regimen (anti-PD-1 mAb, STING agonist, and anti-LAG-3 mAb) to improve HCC treatment.
METHODS: The LAG-3 inhibitor C25 based on a cyclic peptide was chelated with NOTA, radiolabeled with [68Ga]GaCl3. The resulting [68Ga]Ga-NOTA-C25 underwent in vivo PET imaging and ex vivo biodistribution examination in Hepa1-6 tumor-bearing mice. [68Ga]Ga-NOTA-C25 PET was used to monitor the efficacy of monotherapy and dual immunotherapy with anti-PD-1 monoclonal antibody (mAb) and STING agonists. The tumor uptake of [68Ga]Ga-NOTA-C25, tumor response, and survival rates were measured following different treatments. The therapeutic efficacy, molecular mechanisms, and safety of triple immunotherapy were validated using histopathological analysis and flow cytometry.
RESULTS: [68Ga]Ga-NOTA-C25 PET imaging effectively and noninvasively detected LAG-3+ tumor-infiltrating lymphocytes (TILs) in Hepa1-6 tumor-bearing mice. In mice treated with anti-PD-1 mAb, STING agonist, or a combination immunotherapy, [68Ga]Ga-NOTA-C25 PET revealed significantly increased LAG-3+ TIL levels. At the treatment endpoint, the combination of the STING agonist with the anti-PD-1 mAb resulted in a significantly higher uptake (1.35 ± 0.191%ID/g) compared to the control group (0.402 ± 0.017%ID/g), the anti-PD-1 mAb group (0.647 ± 0.037%ID/g), and the STING agonist group (0.874 ± 0.089%ID/g). Uptake of [68Ga]Ga-NOTA-C25 was positively correlated with tumor therapeutic effects and survival rates. Triple immunotherapy with anti-PD-1 mAb, a STING agonist, and anti-LAG-3 mAb further enhanced efficacy compared to any dual immunotherapy regimen, and treatment efficacy was linearly associated with [68Ga]Ga-NOTA-C25 tumor uptake.
CONCLUSIONS: Anti-PD-1 mAb and STING agonists have shown notable synergy in upregulating LAG-3 expression on TILs in HCC, which can be successfully tracked by [68Ga]Ga-NOTA-C25 PET imaging. Furthermore, integration of a triple immunotherapy regimen comprising an anti-PD-1 mAb, STING agonist, and anti-LAG-3 mAb demonstrated a significant improvement in therapeutic efficacy over dual immunotherapy approaches.

Keywords:  Combination immunotherapy; Lymphocyte activation gene 3 (LAG-3); PET imaging; Programmed cell death protein 1 (PD-1); Stimulator of interferon genes (STING)

DOI:  https://doi.org/10.1186/s40364-025-00820-z
J Immunol. 2025 Aug 07. pii: vkaf142. [Epub ahead of print]

SAR-444245, an engineered not-alpha IL-2 leveraging synthetic biology, modulates critical components of the immune system for durable anti-tumoral activity.

Lina Ma, Nicole V Acuff, Jerod L Ptacin, Carolina E Caffaro, Kristine M San Jose, Hans R Aerni, Rob W Herman, Yelena Pavlova, Michael J Pena, David B Chen, Helene V Pham, Christen Buetz, Ean Esche, Lilia K Koriazova, Laura K Shawver, Ingrid B Joseph, Marcos E Milla.

  Anti-tumoral immunity requires coordination of diverse responses leading to durable tumor clearance. Immunotherapy leverages specific mechanisms of the immune system to improve effector cell-mediated attack of tumors. We engineered SAR-444245 [SAR'245, formerly known as THOR-707] as a not-alpha interleukin-2 (IL-2) designed for increased half-life and selective targeting of CD8+ T and natural killer (NK) cells while reducing targeting of immune-suppressive CD4+ regulatory T cells (Tregs). The anti-tumoral efficacy of SAR'245 was investigated using the syngeneic CT-26 mouse model characterized by high infiltration with Tregs and responsiveness to programmed cell-death protein-1 (PD-1) checkpoint inhibitory antibodies. We evaluated SAR'245 pharmacokinetics and peripheral and intra-tumoral pharmacodynamics employing cytometry, histochemistry, RNAseq and secreted cytokine readouts, and in vivo efficacy as single-agent and in combination with an anti-mouse PD-1 antibody. In CT-26 tumor-bearing mice, SAR'245 administration induced peripheral expansion of CD8+ T and NK cells, including T cell memory subpopulations, without significant Treg expansion. SAR'245 stimulated anti-tumor activity that was enhanced in combination with an anti-PD-1 checkpoint inhibitory antibody, promoting both long-term survival and rejection of tumor cells on re-challenge. This agent elevated lymphocytic infiltration of tumors and T cell clonal diversity, eliciting multiple intra-tumoral gene signatures reporting on enhanced effector cell activity and persistence in the tumor microenvironment. Overall, we demonstrate that the IL-2 not-alpha agent SAR'245 induces immune responses that promote infiltration of CD8+ T and NK cells with enhanced effector function, leading to durable antitumoral response. These findings suggest SAR'245 potential for the treatment of solid tumors, particularly in combination with inhibitors of PD-1.

Keywords:  CT-26 tumor; SAR-444245; T cells; cytokines; natural killer cells

DOI:  https://doi.org/10.1093/jimmun/vkaf142