Introduction:PD-1/PD-L1 inhibitors lack evidence-based support in patients aged ≥75 years due to their frequent exclusion from clinical trials. This study aimed to evaluate the safety and efficacy of PRaG therapy-combining PD-1/PD-L1 inhibitors with radiotherapy-specifically in this elderly demographic. Materials and methods:Data were collected from patients aged ≥75 years who received PRaG therapy at our center between 1 January 2019, and 31 December 2024. Eligible patients were required to have at least one post-baseline efficacy evaluation. Tumor response was evaluated according to RECIST v1.1, and adverse events were graded using CTCAE v5.0. Results:A total of 36 elderly patients aged ≥75 years were included, with a median age of 77 years (range: 75-93). The objective response rate (ORR) was 23.5%, and the disease control rate (DCR) was 70.6%. After a median follow-up of 46.3 months, the median progression-free survival (mPFS) was 7.0 months (95% CI: 2.4-11.6 months) and the median overall survival (mOS) was 11.1 months (95% CI: 5.3-16.9 months). The Geriatric Nutritional Risk Index (GNRI) was associated with the efficacy of PRaG therapy, as well as PFS and OS. Any-grade treatment-related adverse events (TRAEs) occurred in 34 patients (94.4%), with 3 patients (8.3%) experiencing ≥Grade 3 TRAEs. No Grade 5 TRAEs were observed. Conclusion:The PRaG regimen appears feasible and tolerable in selected elderly patients with advanced cancer. Given the retrospective nature of this small cohort, an ongoing prospective trial (NCT06112041) will further validate these findings. Combining PRaG with robust nutritional support represents a rational hypothesis for future investigation.
Introduction:Intravenous immunoglobulin (IVIG) therapy can occasionally induce unexpected inflammatory complications. Materials and methods:A case report and literature review. Results:We report a patient with hypogammaglobulinemia and systemic autoimmunity who developed reproducible unilateral anterior uveitis following IVIG administration across multiple formulations. Discontinuation of IVIG resolved the ocular inflammation but caused underlying disease exacerbation. Transition to facilitated subcutaneous immunoglobulin (SCIG) achieved stable serum IgG levels and maintained complete ocular and systemic remission over a four-year follow-up period. Conclusion:This case demonstrates peak-driven immune activation as a plausible mechanism for IVIG-induced uveitis and highlights SCIG as a safe, effective therapeutic alternative that bypasses rapid peak IgG dynamics while preserving immune protection.
Introduction:Type 1 diabetes (T1D) is an autoimmune disease characterized by T cell-mediated destruction of pancreatic β cells. Current insulin therapy does not address autoimmune pathology or restore endogenous β-cell function, highlighting the need for disease-modifying strategies. Methods:We developed a combination therapy integrating a proton pump inhibitor (PPI; omeprazole) with a non-Fc-binding anti-CD3 F(ab')2 antibody fragment (anti-CD3 F(ab')2) to concurrently promote β-cell neogenesis and modulate autoimmune T-cell responses. T1D was induced in nonobese diabetic (NOD) mice using a cyclophosphamide-accelerated protocol (CY-NOD). Following hyperglycemia onset, mice received combination treatment and were evaluated by blood glucose monitoring, flow cytometric analysis of T-cell populations, and assessment of pancreatic β-cell function. Therapeutic efficacy was further examined in spontaneous-onset NOD mice. Results:Combination therapy restored normoglycemia without exogenous insulin, reduced lymphocytic infiltration in pancreatic islets, and preserved endogenous insulin secretion. Treatment decreased pathogenic CD4+ and CD8+ T cells, increased regulatory T cells, and enhanced transforming growth factor-β expression. Comparable and durable glycemic control was observed in spontaneous-onset NOD mice. Conclusions:Concurrent modulation of β-cell function and autoimmune immunity achieved sustained glycemic control in T1D models. The use of clinically approved agents supports the translational potential of this non-insulin-dependent therapeutic strategy.
Abstract Introduction Irradiation and reconstitution has often been used to analyse plasma cell turnover. Here, we characterised the kinetics of plasma cell reconstitution following irradiation, focussing on representation of recipient and donor plasma cells. Methods In a first setup, bone marrow chimeras were generated using congenic Ly5 allotype marked bone marrow transfer after lethal X-ray irradiation. Representation of donor and recipient B cells and plasma cells were tracked in the weeks thereafter. In a second setup, we repeated the reconstitution using plasma cell timestamp mice as recipients and BLIMP1gfp as donor bone marrow, allowing tracing of both recipient- and donor-source plasma cells with fluorescent reporters. Results In recipient spleen and bone marrow in the first setup, B cell and plasma cell numbers returned to homeostasis within 4 weeks of reconstitution. We determined that while B cells were essentially donor-derived by 4 weeks and plasma cells reached maximum donor representation at 4 weeks, they retained a significant fraction of recipient origin plasma cells to at least 8 weeks, the experiment endpoint. This clearly resolved plasma cell origin and revealed recipient plasma cells comprised both persistent and newly formed, the latter being the majority. When irradiated, timestamped mice were reconstituted with B-cell-insufficient µMT bone marrow, leaving irradiated recipient B cells as the sole source of new plasma cells, the recipients generated significantly more nascent plasma cells from endogenous B cells than occurred in the BLIMP1gfp recipients. Conclusion These data suggest that irradiated B cells are at a disadvantage to donor-derived B cells but can give rise to plasma cells when competition is alleviated, here by donor B cell lymphopenia. Bone marrow reconstitution after irradiation thus reveals a population of radiation resistant long-lived plasma cells and B cell or early-stage plasma cell competition for production and retention.
Introduction Targeting tumour antigens is a major challenge in cancer-immunotherapy. We use active vaccination to induce antibodies targeting self-antigen Robo4, which is selectively expressed on tumour vascular endothelium, and supports vascular development. Our previous work showed that a conjugate of Robo4 with a foreign carrier protein induced autoantibodies specific to Robo4, which inhibited angiogenesis and tumour growth.Methods To translate the vaccine protocol to exploit a carrier protein used in routine human vaccination schedules, the well-characterized, non-toxic fragment C of tetanus toxin (TTc) was selected as the carrier protein. Recombinant protein Robo4-TTc (R4-TTc) was produced by Robo4 genetically linked to TTc.Results Priming with the carrier TTc followed by boost with Robo4-TTc (R4-TTc) efficiently induces strong antibody responses to Robo4 and inhibits tumour growth in LLC1 and 4T1 tumour models. The growth inhibition was correlated with anti-Robo4 IgG1 titres. Furthermore, decreased vessel formation and increased immune cell infiltration in tumours from R4-TTc vaccinated mice in the absence of detectable adverse effects on health.Conclusion The data indicate that this vaccination strategy remodels tumour vessels and probably promotes immunogenic pathway activation, therefore repressing tumour growth.
The field of immunology is increasingly intersecting with molecular biology, metabolic biology, and neurobiology (Zhu et al, A neuroimmune circuit mediates cancer cachexia-associated apathy. Science 2025;388:eadm8857; Jaschke et al, Gut-to-brain signaling restricts dietary protein intake during recovery from catabolic states. Cell 2025;188:7481-7494.e16; Zheremyan et al, Regulatory B cells: changing the landscape of immunoregulation and immunotherapy. Cytokine Growth Factor Rev 2025;86:121-36), marking a shift beyond traditional research approaches toward a more comprehensive understanding of the immune system. Central to this integrated perspective is the growing recognition that B cells are not only antibody producers, but also multifunctional cells dynamically modulated by their microenvironment. This comprehensive synthesis of recent research illuminates the dual nature of regulatory B cells (Bregs) as pivotal orchestrators of immune homeostasis. We examine how Bregs, governed by complex metabolic cues, neural signaling pathways, and local tissue microenvironments, can either suppress pathological inflammation or be co-opted to drive disease progression in autoimmunity, cancer, and allergic conditions. Understanding these microenvironmental determinants of Breg function is particularly critical for developing next-generation prognostic tools and targeted therapeutic strategies that effectively modulate B cell activity in various disease states.
Mesenchymal stem cells (MSC) represent a potential target to reverse inflammaging and to halt immunosenescence, as these cells can modulate immune cell responses. Neutrophils, known as polymorphonuclear leukocytes (PMNs), are required for host defence against bacterial pathogens such as Streptococcus pneumoniae; however, their function significantly declines with age. Whether MSCs can reverse the age-driven decline in PMN antibacterial function is unknown. To test that, we cultured MSCs from young and aged mice and tested the paracrine effect of factors present in the conditioned media (CM) on antimicrobial responses of PMNs across host age. The ex vivo treatment with MSCs-CM from aged mice blunted the antimicrobial activity of PMNs from young hosts. However, treatment of PMNs from aged mice with young MSCs-CM significantly increased S. pneumoniae uptake, production of mitochondrial reactive oxygen species, and boosted overall bacterial killing. In exploring the pathways involved, we found that presence of immune modulatory extracellular adenosine in the young MSCs-CM was required for boosting PMN responses. Further, in contrast to aged mice MSCs-CM, young mice MSCs CM increased the responsiveness of aged mice PMNs to adenosine activation by upregulating the A1 adenosine receptor expression. Blocking this high affinity adenosine receptor reversed the rejuvenating effect of young mice MSCs-CM on bacterial killing by PMNs from aged hosts. In summary, this study suggests a potential cell-free therapeutic role of the young host MSC secretome in reversing the age-driven defects in PMN function against bacterial infection. It is the first study to demonstrate an anti-immunosenescence activity of the MSC secretome through extracellular adenosine.
Introduction Tumors downregulate NLRC5 expression to reduce MHC-I and evade CD8(+) T cell-mediated killing. Introducing full-length NLRC5 (N5FL) or NLRC5-CIITA chimeric protein (N5CA) can restore tumor immunogenicity. Here, we elucidated the underlying mechanisms and also evaluated the requirement of NLRC5 expression in antigen-presenting cells (APCs) of the host for tumor control. Materials and methods Nlrc5(-/-) and Nlrc5(+/+) mice were implanted with B16-F10 melanoma expressing N5FL or NC5A. Tumor growth, activation of lymphoid cells, their infiltration into tumors and the requirement for tumor control were assessed. The proteomes of B16-F10 cells expressing N5FL or N5CA were analyzed. Results NLRC5-expressing tumors were efficiently controlled in both Nlrc5(+/+) and Nlrc5(-/-) mice, characterized by infiltration of CD8(+) and CD4(+) cells, natural killer (NK) cells, NK T (NKT) cells and invariant NKT (iNKT) cells, increased tumor vascularization and upregulation of Ccl4 and Cxcl9 genes. Both CD8(+) and NK1.1(+) cells contribute to NLRC5-dependent tumor control. NLRC5 expression in the Tumor Cancer Genome Atlas-skin cutaneous melanoma correlated with NK cell markers and nonclassical MHC-Ib expression. Proteomes of NLRC5-expressing tumor cells showed downmodulation of dominant tumor antigens, but displayed significant changes in the lysosome and the proteasome pathways, upregulated the protein processing in endoplasmic reticulum pathway, and downregulated the autophagy pathway, all of which could impact processing and presentation of subdominant tumor antigens. Conclusion NLRC5 expression in APCs is dispensable for NLRC5-dependent antitumor immunity. NLRC5-dependent tumor control requires both CD8(+) and NK1.1(+) cells. Tumor-intrinsic NLRC5 promotes vasculature that is permissive to infiltration by antitumor immune cells. In addition to upregulating MHC-I, NLRC5 may enhance alternative antigen-processing pathways and attenuate autophagic degradation of MHC-I, thereby augmenting tumor immunogenicity.
Cancer stem cells (CSCs) are a small subset of cells that possess unique characteristics, including the ability to initiate and sustain tumor growth, self-renew, and differentiate into various types of cancer cells. They play a crucial role in tumor progression, metastasis, and recurrence. In recent years, CSCs have garnered significant attention due to their involvement in therapeutic resistance to both conventional and novel cancer treatments, including immunotherapy. This review delves into the fundamental properties of CSCs, molecular, cellular, and metabolic, focusing particularly on their immunomodulatory effects. We propose a comprehensive model that reflects the involvement of CSCs in various interlinked contexts, including key signaling pathways, the suppressive microenvironment, and the surrounding stromal components. Through this triaxial conceptualization, we highlight the key role of the stemness-orchestrated architecture in contributing to therapeutic failure. We present evidence gathered from diverse clinical settings, demonstrating a tight correlation between a stem tumor phenotype and poor clinical outcomes, including reduced survival rates and dampened response to immune checkpoint inhibitors (ICB). Finally, we propose therapeutic interventions specifically designed to disrupt the architecture of cancer stemness. These include vaccination against CSC antigens, differentiation therapies, cellular therapies, and combinatorial approaches. In summary, this review apprises an integral, up-to-date perspective that redefines the role of CSCs, positioning them at the core of immunotherapeutic resistance.
Introduction:Hyaluronidase-facilitated subcutaneous immunoglobulin 10% (fSCIG 10%) is a unique and effective treatment for primary immunodeficiency disease (PID), allowing for less frequent administration than conventional subcutaneous immunoglobulin therapies. Methods:The pharmacokinetics (PK) of fSCIG 10% in pediatric patients (aged 2 to <16 years at screening) with PID was assessed in a prospective, phase 3, open-label, multicenter, clinical trial conducted in the USA. Patients previously treated with intravenous or conventional subcutaneous immunoglobulin therapy (consistent dose for ≥3 months) received fSCIG 10% via a dose ramp-up schedule for ≤6 weeks (Epoch 1), then at full target dose every 3-4 weeks for ≤3 years (Epoch 2). Serum total immunoglobulin G (IgG) trough levels were reported throughout Epoch 2 across pediatric age groups (2 to <6, 6 to <12, and 12 to ≤16 years); serial PK were characterized at the Month 6 infusion. In total, 44 patients (mean age: 9.0 years; 59% male and 91% White) were eligible for the study. Results:Mean total IgG trough levels during Epoch 2 were similar across age groups. Geometric mean area under the IgG concentration-time curve per week ranged from 63.4 to 76.8 g·day/L, and body weight-adjusted apparent clearance ranged from 1.5 to 1.9 ml/day/kg. Conclusion:This study showed that serum total IgG trough levels were effectively maintained in pediatric patients with PID treated with fSCIG 10%, regardless of age. The dosing strategy for pediatric patients should be informed by assessing individual IgG levels and clinical status as for adults. Clinical trials registration:The study is registered with the ClinicalTrials.gov registry at https://clinicaltrials.gov/ct2/study/NCT03277313 (ClinicalTrials.gov Identifier: NCT03277313).
Gene-engineered T-cell products have been developed for immunotherapy to treat cancers, with great success observed in haematological malignancies but limited efficacy in treating solid cancers. TCR-engineered T cells utilize transferred TCRs targeting tumour-associated and cancer-specific peptides presented by MHC molecules. The CD3ζ chains are part of the TCR-CD3 complex expressed by T cells and mediate signal transduction when the TCR binds to MHC-presented peptides. In this study, we explored whether co-stimulation domains, that were effective in improving the function of T cells engineered with chimeric antigen receptors (CARs), can be exploited to improve the functionality of TCR-engineered T cells. We inserted the signalling domains of CD28 or 4-1BB at the membrane proximal or the membrane distal position of the intracellular tail of CD3ζ and engineered human T cells to express a specific TCR in combination with either modified CD3ζ or unmodified control. Antigen-specific in vitro stimulation assays revealed that T cells expressing CD3ζ constructs with CD28 signal domains displayed enhanced peptide-specific IL-2 production and, following repeated antigen stimulation, expanded to substantially greater numbers than T cells expressing unmodified CD3ζ. Importantly, greater expansion seen with the CD28-containing ζ did not result in any reduction of effector function as assessed by peptide-specific cytotoxicity and cytokine production. The data indicate that modification of the CD3ζ chain with a CD28 signal motif provides an opportunity to improve antigen-specific expansion and effector function of TCR-engineered T cells by combining signal 1 and co-stimulatory signal 2 in one molecular TCR-CD3 complex.
The Systemic Immune-Inflammation Index (SIII; neutrophils/lymphocytes × platelets) is a low-cost biomarker proposed to predict outcomes with immune checkpoint inhibitors (ICIs). This study evaluated associations of baseline and early on-treatment changes in SIII with overall survival (OS) for common ICI regimens. Patients with advanced cancer treated with ICIs at a UK centre were categorized by baseline SIII (above vs. below the median) and by changes at 3-6 weeks (increase/decrease). OS was analysed using Kaplan-Meier estimates. Adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) were calculated using multivariable Cox regression. Among 2578 patients included, 1514 deaths occurred over a median follow-up of 2.6 years. Common regimens included pembrolizumab or atezolizumab with (15.9%) or without chemotherapy (13.9%) for NSCLC, and nivolumab plus ipilimumab for melanoma (12.6%). Lower baseline SIII was associated with improved OS (28.1 vs. 11.1 months; aHR 0.56, 0.50-0.62), with a weaker association observed in those receiving ICI-targeted therapy combinations. An on-treatment increase in SIII was linked to reduced OS (16.8 vs. 21.5 months; aHR 1.33, 1.18-1.49). Patients with low baseline SIII and an on-treatment decline had the longest OS (33.2 months), whereas those with high baseline SIII and an on-treatment increase had the shortest (8.2 months; aHR 2.88, 2.41-3.44; interaction between baseline and on-treatment SIII P < 0.001). SIII is a low-cost, readily available biomarker. Both baseline SIII levels and on-treatment changes in SIII are significantly associated with OS. SIII may help identify patients who could benefit from closer monitoring or treatment adjustments.
Streptococcus pneumoniae (pneumococcus) is a leading cause of bacterial meningitis worldwide and is associated with cerebrovascular complications and long-term neurological sequelae. These outcomes are largely driven by an excessive yet ineffective neuroinflammatory response. Although pneumococci express multiple virulence factors that enable immune evasion, how these factors modulate phagocytic responses in the central nervous system remains unclear. Here, we identify neuraminidase A (NanA) as a critical regulator of phagocytic activation in microglia and macrophages. Using murine and human microglia and RAW 264.7 macrophages, we show that NanA deficiency increases bacterial adhesion, indicating enhanced immune recognition, but paradoxically promotes intracellular bacterial survival. Despite elevated expression of the phagocytic marker CD68, microglia infected with NanA-deficient pneumococci fail to efficiently eliminate intracellular bacteria, as evidenced by unchanged levels of the lysosomal enzyme cathepsin 3 compared with NanA-expressing strains. Treatment with recombinant NanA restored phagocytic activation and significantly enhanced clearance of NanA-deficient bacteria. This effect was dependent on NanA sialidase activity, as enzymatically inactive NanA failed to restore immune sensing. Notably, this immunomodulatory function was specific to the secreted form of NanA produced by the invasive TIGR4 strain and was not observed with membrane-anchored NanA from D39-derived mutants. Together, these findings reveal an unexpected role for NanA in promoting effective innate immune activation and bacterial clearance, highlighting its potential as a therapeutic target for pneumococcal meningitis and invasive pneumococcal disease.
Introduction:Programmed cell death protein 1 (PD-1) inhibitors improve survival in advanced melanoma but can induce immune-related adverse events (irAEs). IrAEs have been linked to better outcomes. However, it remains unclear whether specific irAE types drive this effect and how corticosteroid treatment of irAEs influences survival. Materials and methods:A seven-year retrospective cohort study of 301 patients with advanced cutaneous melanoma treated with single-agent PD-1 inhibition at Sahlgrenska University Hospital. irAEs were identified using CTCAE v4.0/v5.0, and irAEs requiring systemic corticosteroids or endocrine replacement therapy were included. Corticosteroid therapy was categorized as low dose (≤0.5 mg/kg prednisolone equivalent) or high dose (>0.5 mg/kg). Overall survival (OS) was assessed using Kaplan-Meier and Cox models, including time-dependent analyses to address immortal time bias. Results:Patients with irAE (109 of 301 patients) had longer OS than those without irAEs. Of the eight most common irAEs, four were associated with superior survival, one was borderline significant, and three were non-significant. Rheumatic irAEs and late-onset thyroid irAEs remained associated with improved OS after adjustment for negative prognostic factors and immoral time bias. Colitis irAE were borderline significant in univariate analysis. Sarcoidosis-like and hypophysitis irAEs were rare but conferred excellent outcomes. Hepatitis, nephritis, and pneumonitis were not associated with better survival. Most survival-associated irAEs were treated with a lower start dose of corticosteroids but duration and time to onset were similar to non-survival-associated irAEs. Conclusion:Rheumatic, endocrine, and sarcoidosis-like irAEs are markers of superior survival and suggest that lower initial corticosteroid doses may preserve PD-1 inhibitor efficacy.
Introduction:Mismatch repair-deficient (dMMR) colorectal cancers (CRCs) exhibit variable clinical responses to immune checkpoint inhibitors (ICIs) despite their high immunogenicity. Methods:To investigate the molecular and spatial determinants of this heterogeneity, we analyzed five metastatic sites (colon, liver, peritoneum, left ovary, and right ovary) from a dMMR CRC patient treated with pembrolizumab using bulk and single-cell RNA sequencing combined with multiplex immunohistochemistry. Results:Responsive lesions were characterized by enriched cytotoxic and interferon-γ signatures, greater CD8+ T-cell infiltration, and close spatial proximity between programmed death-ligand 1(PD-L1)+ tumor cells and M1-like macrophages. In contrast, resistant lesions demonstrated reduced effector cell presence and were enriched in immunosuppressive programs, including SPP1+ and CD163+ macrophages, noncanonical WNT5A/B signaling, and TGF-β-mediated matrix remodeling. Conclusion:Collectively, these findings highlight the importance of spatial immune architecture and macrophage polarization in shaping ICI responses in dMMR CRC and underscore the need for spatial profiling to guide immunotherapy strategies in metastatic disease.
Introduction:The cytokine CD137 (TNFRSF9, 4-1BB) is best known as a T cell costimulatory molecule. However, CD137 is also part of a negative feedback mechanism that limits T cell activation, and that is employed by regulatory T cells (Tregs) to prevent an overstimulation of T cells and subsequent autoimmune damage. CD137 has been identified as the gene that most significantly distinguishes intra- from extratumoral Tregs. CD137+ Tregs are more immunosuppressive than CD137- ones, and CD137 levels on intratumoral Tregs correlate with a poor prognosis for cancer patients. In addition, CD137 is also ectopically expressed on several types of malignant cells that usurp this physiological feedback mechanism to evade immune surveillance. This suggests CD137 as a target for eliminating or changing intratumoral Tregs. Here we demonstrate that a murine CD137-specific aptamer can bind to CD137 on malignant cells and T cells and be internalized. Methods and Results:We fused the aptamer to short hairpin (sh) RNAs that are specific for Enhancer of zeste homolog 2 (EzH2) or neuropilin-1 (Nrp1), and demonstrated their uptake into CD137+ malignant cells and Tregs, and the subsequent downregulation or EzH2 and Nrp1. Conclusion:This study confirms CD137 as a target for tumor immunotherapy and introduces CD137 aptamer-shRNA chimeras as novel tools to be evaluated for their usefulness in cancer treatment.
T cell (Tc) receptor (TCR)-based cell therapies have shown clinical efficacy across many cancer types and represent an attractive strategy for targeting solid tumors. However, the immunosuppressive tumor microenvironment, downregulation of target antigen and HLA, and the need for an autologous source limit the efficacy and the accessibility of TCR-Tc therapies. Early clinical trials have shown the potential of natural killer cells (NKs) as a therapy to treat hematological and solid cancers. Allogeneic NKs, engineered to express a TCR, represent a novel and promising strategy overcoming the limitations of T and NKs therapies. Here we describe the development of a product consisting of NKs engineered to express an affinity-enhanced TCR recognizing MAGE-A4, a clinically validated tumor antigen expressed across several solid tumors. The introduction of the TCR does not disrupt the innate functionality of NKs and adds TCR-mediated specific killing of antigen-positive targets. In fact, the innate potential of the NKs appears to be enhanced by the presence of the CD3-TCR complex, creating NKs with increased potency. TCR-NKs are faster, more potent than TCR-Tc and retain killing activity in the absence of TCR target antigen thus potentially overcoming tumor heterogeneity and/or antigen loss. Lastly, TCR-NKs are not activated when co-cultured with normal cells, displaying a safe profile. Combining the innate cytotoxicity of NKs with MAGE-A4-specific targeting of an affinity-enhanced TCR, results in a potent and safe cellular product representing a promising and novel therapeutic off-the-shelf paradigm for the treatment of many solid cancers.
Abstract Introduction Synthetic T cell receptor (TCR) engagers are cancer therapeutics that activate T cells through recognition of antigens on the tumor cell surface. Immune-mobilizing monoclonal TCRs against cancer (ImmTAC) are composed of the extracellular domains of the alpha and beta chains of an affinity-enhanced TCR recognizing a tumor-associated antigenic peptide-major histocompatibility complex (MHC) complex linked to an scFv fragment of an antibody against CD3ε. A first-in-class ImmTAC, Tebentafusp, is approved for the treatment of metastatic uveal melanoma. Here we asked how ImmTACs activate human primary cytotoxic T lymphocytes (CTL) in response to antigen-presenting tumor target cells. Materials and methods We used a recently established experimental strategy to generate active and matched suppressed CTL in vitro. Results ImmTACs could elicit tumor cell cytolysis in response to endogenous antigen presentation by both active and suppressed CTL, but much less so for IFNγ secretion, in a manner dependent on the engager affinity for CD3ε. ImmTACs did so by enhancing the efficient execution of subcellular CTL polarization steps required for effective cytolysis and could trigger calcium signaling. Conclusion These data establish that ImmTACs are powerful inducers of CTL cytotoxicity and do so with a comparable efficacy and mechanism as direct engagement of a TCR by peptide-MHC. ImmTACs retain this capability under suppressive conditions comparable to those in the tumor microenvironment.
T-cell receptors can sense cancer-associated changes in cellular proteins, lipids, metabolites, and stress pathways, enabling immune-mediated tumour elimination in some patients. These receptors underpin T-cell receptor-based immunotherapies, yet their isolation from clinical samples remains challenging due to labour-intensive workflows, dependence on prior antigen knowledge, and loss of cell viability. We developed an optimized flow cytometry-based assay, termed the T107 assay, to isolate viable cancer-reactive T-cells directly from clinical samples. Following short-term exposure to cancer cells, responding T-cells are identified by simultaneous surface detection of tumour necrosis factor and the degranulation marker CD107a, enabling recovery of live antigen-reactive cells for downstream analysis. The T107 assay enabled rapid identification of cancer-reactive T-cells from tumour-infiltrating lymphocyte products derived from melanoma and sarcoma patients. The assay supported phenotypic and functional characterization of αβ and γδ T-cell receptor populations, including CD4+ and CD8+ subsets, responding to both patient-specific and shared cancer antigens. Isolation of viable responding cells enabled high-resolution receptor sequencing, generation of functional T-cell clones, determination of antigen specificity and major histocompatibility complex restriction or independence. Paired receptors were engineered into primary T-cells to generate T-cell receptor-engineered products capable of recognizing multiple cancer types. The T107 assay provides a rapid and robust method for antigen-agnostic procurement of viable cancer-reactive T-cells and their receptors from clinical material. This approach removes key bottlenecks in T-cell receptor discovery and is expected to accelerate development of T-cell receptor-based immunotherapies across a broad range of cancers.
Cancer vaccines offer transformative potential in oncology, especially with advances in mRNA technologies. To accelerate advances in cancer vaccine research and capitalize on its COVID-19 vaccine leadership, the UK Government has launched the UK Vaccine Innovation Pathway (VIP) through a partnership between the National Institute for Health and Care Research (NIHR), NHS England, and pharmaceutical partners. Its innovative approaches to trial delivery have enabled a 500% increase in patient recruitment with 33 trials open or recently closed across 85 sites and 11 cancer types. Working alongside the Cancer Vaccine Launchpad (CVLP), which pre-screens patients across 55 NHS sites, VIP offers streamlined trial set-up, decentralized delivery, and equity-focused design. The UK's approach aligns scientific innovation with rapid clinical deployment, creating a scalable, patient-centred model for delivering individualized therapies. This article outlines the strategic framework, outcomes, and lessons from the VIP and CVLP to inform future national strategies in cancer vaccine deployment.
