Tumor-associated Antigens Research Articles

Predicting Antigen-Specificities of Orphan T Cell Receptors from Cancer Patients with TCRpcDist.

Approaches to analyze and cluster T-cell receptor (TCR) repertoires to reflect antigen specificity are critical for the diagnosis and prognosis of immune-related diseases and the development of personalized therapies. Sequence-based approaches showed success but remain restrictive, especially when the amount of experimental data used for the training is scarce. Structure-based approaches which represent powerful alternatives, notably to optimize TCRs affinity toward specific epitopes, show limitations for large-scale predictions. To handle these challenges, TCRpcDist is presented, a 3D-based approach that calculates similarities between TCRs using a metric related to the physico-chemical properties of the loop residues predicted to interact with the epitope. By exploiting private and public datasets and comparing TCRpcDist with competing approaches, it is demonstrated that TCRpcDist can accurately identify groups of TCRs that are likely to bind the same epitopes. Importantly, the ability of TCRpcDist is experimentally validated to determine antigen specificities (neoantigens and tumor-associated antigens) of orphan tumor-infiltrating lymphocytes (TILs) in cancer patients. TCRpcDist is thus a promising approach to support TCR repertoire analysis and TCR deorphanization for individualized treatments including cancer immunotherapies.

Bioinspired Hf-based metal-organic framework radiosensitizer for nitric oxide-assisted radio-immunotherapy

Radiotherapy is a crucial antineoplastic approach in clinical practice, but it often suffers from low therapeutic efficacy due to inadequate deposition of X-ray radiation and limited inhibition of metastatic tumors. Here, a bioinspired Hf-based metal-organic framework (Hf-MOF) nano-radiosensitizer (SHMR) is elaborately designed for boosting radio-immunotherapy by synergizing radio-sensitization with nitric oxide-assisted immune microenvironment remodeling. The engineered SHMR is constructed by wrapping RGD peptide-modified erythrocyte membrane onto sodium nitroprusside-loaded Hf-MOF. In vitro and in vivo experiments demonstrate that SHMR can induce immunogenic cell death and release abundant tumor-associated antigens to promote dendritic cells maturation and T cells activation under X-ray irradiation. Importantly, nitric oxide (NO) released from SHMR can not only relieve tumor hypoxia to alleviate radiotherapy resistance, but also reprogram tumor microenvironment, thereby reshaping the extracellular matrix barrier and enhancing immune cells infiltration. Specifically, SHMR in conjunction with αPD-L1 therapy exhibits favorable therapeutic outcomes in bilateral tumor and metastatic tumor models. This work creates a practical nano-radiosensitizer to achieve effective radiotherapy and NO-mediated tumor microenvironment reconstruction, providing a promising strategy for potentiating the radio-immunotherapy against “immune-cold” tumors.

Impact of N-Terminal PEGylation on Synthesis and Purification of Peptide-Based Cancer Epitopes for Pancreatic Ductal Adenocarcinoma (PDAC).

Peptide-based cancer vaccines have shown promising results in preclinical trials focusing on tumor immunotherapy. However, the presence of hydrophobic amino acid segments within these peptide sequences poses challenges in their synthesis, purification, and solubility, thereby hindering their potential use as cancer vaccines. In this study, we successfully synthesized peptide sequences derived from mesothelin (MSLN), a tumor-associated antigen overexpressed in pancreatic ductal adenocarcinoma (PDAC) by conjugating them with monodisperse polyethylene glycol (PEG). By PEGylating mesothelin epitopes of varying lengths (ranging from 9 to 38 amino acids) and hydrophobicity (60-90%), we achieved an effective method to improve the peptide yield and facilitate the processes of synthesis and purification. PEGylation significantly enhanced the solubility, facilitating the single-step purification of lengthy hydrophobic peptides. Most importantly, PEGylation did not compromise cell viability and had little to no effect on the immunogenicity of the peptides. In contrast, the addition of a palmitoyl group to increase immunogenicity led to reduced yield and solubility. Overall, PEGylation proves to be an effective technique for enhancing the solubility and broadening the range of utility of diverse long hydrophobic peptides.

Safety, tolerability, and immunogenicity of WGc-043 in subjects with EBV-positive cancers: Results from an investigator-initiated trial.

139 Background: The Epstein-Barr virus (EBV) persists and spreads after infection in humans, leading to the occurrence and metastasis of a variety of cancers, posing great challenges in the treatment of cancer.. Conventional cancer therapies tend to have limited success and significant side effects. Therefore, there is an urgent need to develop more safe and efficient treatments such as innovative mRNA vaccines, which provide a new approach to cancer immunotherapy. WGc-043, an mRNA vaccine targeting EBV-positive tumor associated antigens, was evaluated for safety, tolerability, and immunogenicity in a prospective, single-center, investigator-initiated study. Methods: The study included 12 patients aged ≥18 with EBV-positive recurrent or metastatic nasopharyngeal carcinoma. Eligibility criteria included at least one measurable lesion, ECOG performance status 0-1, expected survival greater than three months, and no autoimmune disease. Participants were divided into three dose cohorts (25 μg, 50 μg, 100 μg) and received five administrations followed by optional continued monthly treatment of WGc-043 by intramuscular injection. The study assessed safety by adverse event monitoring, immune response based on the peripheral blood and tumor tissue sample analysis and efficacy according to imaging guidelines and irRECIST version 1.1. Results: The study results demonstrated that WGc-043 had a favorable safety profile with only grade 1 or 2 adverse events and fever (4/12) reported as the most common adverse event. Notably, two patients achieved partial response (PR) and five patients had stable disease (SD), highlighting the potential clinical efficacy of WGc-043. In addition, most (91.7%) subjects showed a significant reduction in plasma EBV DNA levels after administration. Immunogenicity analysis using IFN-γ ELISpot showed that 8 (66.7%) of the 12 enrolled patients developed strong specific immune responses against EBV-associated antigens, indicating that WGc-043 is a potent immunotherapy. Conclusions: This exploratory study underscores the safety and potential efficacy of WGc-043 as an mRNA vaccine for EBV-associated cancers, demonstrating its ability to induce specific immune responses and achieve substantial disease control in a challenging patient population, although further studies in larger clinical trials are needed. These results not only support the advancement of WGc-043 as a candidate for immunotherapy in EBV-positive cancers, but also highlight the translational potential of mRNA vaccine technology in the oncology landscape. Clinical trial information: NCT05714748 . [Table: see text]

Discovery of high-expressing lncRNA-derived sORFs as potential tumor-associated antigens in hepatocellular carcinoma.

This study is based on deep mining of Ribo-seq data for the identification of lncRNAs that have highly expressed sORFs in HCC. In this paper, dynamic prospects associated with sORFs acting as newly defined tumor-specific epitopes are discussed with possible improvement in strategies for tumor immunotherapy. Using ribosome profiling to identify and characterize sORFs within lncRNAs in HCC, identify potential therapeutic targets and tumor-specific epitopes applicable for immunotherapy. MetamORF performed the identification of sORFs with deep analysis of the data of ribosome profiling in lncRNAs associated with HCC. The translation efficiency in these molecules was estimated, and epitope prediction was done by pVACbind. Peptide search was done to check the presence of micropeptides translated from these identified sORFs. validated translational activity and identified potential epitopes. Higher translation efficiency was noted in the case of lncRNAs associated with HCC compared to normal tissues. Of particular note is ORF3418981, which results in the highest expression and has supporting experimental evidence at the protein level. Epitope prediction identified a putative epitope at the C-terminus of ORF3418981. This study uncovers the as-yet-unknown potential of lncRNA-derived sORFs as sources of tumor antigens, shifting the research focus from protein-coding genes to non-coding RNAs also in the HCC context. Moreover, this study highlights the contribution of a subset of lncRNAs, especially LINC00152, to the development of tumors and modulation of the immune response by its sORFs.

Precise Regulation of Reactive Oxygen Species in Tumor Microenvironment for Alleviating Inhibitory Immunogenic Cell Death.

High level of C (ROS) within the tumor microenvironment (TME) not only damage tumor cells but also diminish the efficacy of immunogenic cell death (ICD) and the activity of tumor-infiltrating T lymphocytes, thereby limiting the effectiveness of immunotherapy. Therefore, precise modulation of ROS level is crucial to effectively eliminate tumor cells and activate ICD-induced immunotherapy. Here, an intelligent yolk shell nanoplatform (SPCCM) that features calcium carbonate shells capable of decomposing under acidic TME conditions, thereby releasing the natural antioxidant proanthocyanidins (PAs) and the photosensitizer Ce6 is designed. PAs scavenge ROS within tumors, extending the survival time of T lymphocytes, while Ce6, as an ICD inducer, generates high ROS concentrations upon laser irradiation, thus reaching the toxic threshold within tumor cells and inducing apoptosis. The resulting apoptotic cells serve as tumor-associated antigens, promoting dendritic cells (DCs) maturation, and activating ICD. By effectively neutralizing ROS in the TME, PAs sustainably reduce ROS level, thereby enhancing DCs activation and restoring antitumor immune cell activity suppressed by ROS (resulting in an eightfold increase in DCs activation). This study demonstrates effective synergistic effects between photodynamic therapy and immunotherapy by precisely modulating ROS level.

Conversion of anti-tissue factor antibody sequences to chimeric antigen receptor and bi-specific T-cell engager format

BackgroundThe efficacy of antibody-targeted therapy of solid cancers is limited by the lack of consistent tumour-associated antigen expression. However, tumour-associated antigens shared with non-malignant cells may still be targeted using conditionally activated-antibodies, or by chimeric antigen receptor (CAR) T cells or CAR NK cells activated either by the tumour microenvironment or following 'unlocking' via multiple antigen-recognition. In this study, we have focused on tissue factor (TF; CD142), a type I membrane protein present on a range of solid tumours as a basis for future development of conditionally-activated BiTE or CAR T cells. TF is frequently upregulated on multiple solid tumours providing a selective advantage for growth, immune evasion and metastasis, as well as contributing to the pathology of thrombosis via the extrinsic coagulation pathway.MethodsTwo well-characterised anti-TF monoclonal antibodies (mAb) were cloned into expression or transposon vectors to produce single chain (scFv) BiTE for assessment as CAR and CD28-CD3-based CAR or CD3-based BiTE. The affinities of both scFv formats for TF were determined by surface plasmon resonance. Jurkat cell line-based assays were used to confirm the activity of the BiTE or CAR constructs.ResultsThe anti-TF mAb hATR-5 and TF8-5G9 mAb were shown to maintain their nanomolar affinities following conversion into a single chain (scFv) format and could be utilised as CD28-CD3-based CAR or CD3-based BiTE format.ConclusionBecause of the broad expression of TF on a range of solid cancers, anti-TF antibody formats provide a useful addition for the development of conditionally activated biologics for antibody and cellular-based therapy.

Engineered bacteria breach tumor physical barriers to enhance radio-immunotherapy

Radiotherapy widely applied for local tumor therapy in clinic has been recently reinvigorated by the discovery that radiotherapy could activate systematic antitumor immune response. Nonetheless, the endogenous radio-immune effect is still incapable of radical tumor elimination due to the prevention of immune cell infiltration by the physical barrier in tumor microenvironment (TME). Herein, an engineered Salmonella secreting nattokinase (VNPNKase) is developed to synergistically modulate the physical and immune characteristics of TME to enhance radio-immunotherapy of colon tumors. The facultative anaerobic VNPNKase enriches at the tumor site after systemic administration, continuously secreting abundant NKase to degrade fibronectin, dredge the extracellular matrix (ECM), and inactivate cancer-associated fibroblasts (CAFs). The VNPNKase- dredged TME facilitates the infiltration of CD103+ dendritic cells (DCs) and thus the presentation of tumor-associated antigens (TAAs) after radiotherapy, recruiting sufficient CD8+ T lymphocytes to specifically eradicate localized tumors. Moreover, the pre-treatment of VNPNKase before radiotherapy amplifies the abscopal effect and achieves a long-term immune memory effect, preventing the metastasis and recurrence of tumors. Our research suggests that this strategy using engineered bacteria to breach tumor physical barrier for promoting immune cell infiltration possesses great promise as a translational strategy to enhance the effectiveness of radio-immunotherapy in treating solid tumors.

67 Preclinical evaluation of PSMA-based68Ga-/225Ac-labeled radiotheranostic pair in a syngeneic mouse model of renal cell carcinoma

Abstract Background Despite the significant progress achieved with PD-1/PD-L1 inhibitors in the treatment of metastatic renal cell carcinoma (mRCC), most patients ultimately progress. Targeted radiotheranostics offer a new potential approach. Although a radiotheranostic platform targeting the prostate-specific membrane antigen (PSMA) has been tested in mRCC in patients preliminarily, thorough preclinical optimization has not been reported. Prostate-specific membrane antigen (PSMA) is overexpressed in tumor-associated neovascular endothelial cells of many solid tumors, including metastatic RCC. Furthermore, radiopharmaceutical therapy using β- and α-particle emitting agents causes immunomodulation by inducing immunogenic cell death, and release of tumor-associated antigens, potentially enhancing inflammatory phenotype. Here, we investigated whether PSMA-based radiotheranostics can be utilized to improve the efficacy of PD-1 therapy. Methods The PSMA+ RENCA model was developed by lentiviral transduction of RENCA (wt) cells and then characterized for basal and IFN-g induced PD-L1 expression. 68Ga-L1 and 225Ac-L1 were synthesized in high radiochemical yield and purity following our reported methods. Male and female BALB/c mice were used for tumor inoculation. 68Ga-L1 was evaluated in small animal PET/CT imaging in flank and PET/MR imaging in orthotopic implantation. A treatment study was conducted to assess the effect of combination therapy in seven groups in the flank tumors at 2 weeks post-inoculation: Control (saline); PD-1 (10 mg/kg); Anti-PD-1 (10 mg/kg)+axitinib (tyrosine kinase inhibitor, 5 mg/kg, oral gavage, for five days/wk); 225Ac-L1 (37 kBq); 225Ac-L1 (2×37 kBq, 1 wk apart); [225Ac-L1 (37 kBq)+PD-1 (10 mg/kg) and [225Ac-L1 2×37 kBq)+PD-1 (10 mg/kg)]. Therapeutic efficacy was assessed by tumor weight and time to progression of tumor volume doubling (TVD). To determine the mechanism of action of the 225Ac-L1/anti-PD-1 combination treatment, tumor-infiltrating lymphoid populations from tumor samples were collected at day 30, and Fluorescence-Activated Cell Sorting analysis was done with fluorochrome-labeled antibodies against CD45, CD3, CD8, IL10, and IL12. Results 68Ga-L1 and 225Ac-L1 confirmed 10-fold and 2-fold higher uptake, respectively, in the PSMA+ RENCA cells compared to RENCA (wt) cells. PET imaging in the flank model displayed ~7-fold higher accumulation of 68Ga-L1 in PSMA+ RENCA than the RENCA (wt). Two-fold higher accumulation of 68Ga-L1 was observed in orthotopic tumors than the normal kidneys during 1-3 h post-injection. Significant lung metastases were detected with 68Ga-L1 PET at 3 weeks in mice with orthotopic tumors. A combination therapy study was conducted using anti-PD-1 and anti-PD-1+axitinib and compared the efficacy with 225Ac-L1 as a single agent (37 kBq and 2×37 kBq, 1 wk apart) and in combination with PD-1. Median TVD increased from 12 d (control) to 16 d (anti-PD-1), 16 d (anti-PD-1+axitinib), 24 d [225Ac-L1 (37 kBq) P<0.001], 24 d [225Ac-L1 (2 × 37 kBq) P<0.0001}, 30 d [anti-PD-1+225Ac-L1 (1×37 kBq) P<0.0001], and undefined, [anti-PD-1+225Ac-L1 2×37 kBq), P<0.0001], respectively. Furthermore, treatment with 225Ac-L1 (2×37 kBq, 1 wk) resulted in a significant lowering of tumor growth (P< 0.01) compared to control, whereas anti-PD-1 (vs. control) alone moderately reduced tumor growth. The combination of the treatment of [PD-1+225Ac-L1 (2×37 kBq), P=0.0001] was the most effective in enhancing tumor growth inhibition compared with the PD-1+axitinib group. Flow cytometry of tumor-infiltrating immune cells of the treatment groups PD-1+225Ac-L1(37 kBq) and PD-1+225Ac-L1 (2×37 kBq) revealed a higher proportion of effector CD3+CD8+ T cells, accompanied by a significant decline in the proportion of immunosuppressive and pro-tumoral CD8+IL10+ T cells and increase in antitumor CD8+IL12+ T cells compared to untreated and treatment control groups (PD-1 or PD-1+axitinib groups). Conclusions Combining radiotheranostic platform, 68Ga-L1/225Ac-L1 with PD-1 therapy reduces tumor burden and improves TVD in a syngeic model of RCC. This is a promising option for metastatic RCC patients with low and heterogeneous PSMA expression. Translation of this method will be pursued actively. DOD CDMRP Funding: yes

Prophylactic and therapeutic cancer vaccine with continuous localized immunomodulation

Selective in vivo immune cell manipulation offers a promising strategy for cancer vaccines. In this context, spatiotemporal control over recruitment of specific cells, and their direct exposure to appropriate immunoadjuvants and antigens are key to effective cancer vaccines. We present an implantable 3D-printed cancer vaccine platform called the ‘NanoLymph’ that enables spatiotemporally-controlled recruitment and manipulation of immune cells in a subcutaneous site. Leveraging two reservoirs each for continuous immunoadjuvant release or antigen presentation, the NanoLymph attracts dendritic cells (DCs) on site and exposes them to tumor-associated antigens. Upon local antigen-specific activation, DCs are mobilized to initiate a systemic immune response. NanoLymph releasing granulocyte-macrophage colony-stimulating factor and CpG-oligodeoxynucleotides with irradiated whole cell tumor lysate inhibited tumor growth of B16F10 murine melanoma in a prophylactic and therapeutic vaccine setting. Overall, this study presents the NanoLymph as a versatile cancer vaccine development platform with replenishable and controlled local release of antigens and immunoadjuvants.

TALEN-edited allogeneic inducible dual CAR T cells enable effective targeting of solid tumors while mitigating off-tumor toxicity

Adoptive cell therapy using chimeric antigen receptor (CAR) T-cells has proven to be lifesaving for many cancer patients. However, its therapeutic efficacy has been limited in solid tumors. One key factor for this are cancer-associated fibroblasts (CAFs), that modulate the tumor microenvironment (TME) to inhibit T cell infiltration and induce “T cell dysfunction”. Additionally, the sparsity of tumor-specific antigens (TSA) and expression of CAR-directed tumor-associated antigens (TAA) on normal tissues often results in “on-target off-tumor” cytotoxicity, raising safety concerns. Using TALEN-mediated gene editing, we present here an innovative CAR-T cell engineering strategy to overcome these challenges. Our allogeneic "Smart CAR T-cells” are designed to express a constitutive CAR, targeting FAP+ CAFs in solid tumors. Additionally, a second CAR targeting a Tumor Associated Antigen (TAA) such as mesothelin is specifically integrated at a TCR signaling-inducible locus like PDCD1. FAPCAR-mediated CAF targeting induces expression of the mesothelin-CAR, establishing an IF/THEN-gated circuit sensitive to dual antigen sensing. Using this approach, we observe enhanced anti-tumor cytotoxicity, while limiting "on-target off-tumor" toxicity. Our study thus demonstrates TALEN-mediated gene editing capabilities for design of allogeneic IF/THEN-gated Dual CAR T-cells which efficiently target immunotherapy-recalcitrant solid tumors while mitigating potential safety risks, encouraging clinical development of this strategy.

A novel shark VNAR antibody-based immunotoxin targeting TROP-2 for cancer therapy

TROP-2, a tumor-associated antigen, has been implicated in the progression of various epithelial tumors. Due to its favorable expression profile, TROP-2 has emerged as a promising target for antibody–drug conjugates (ADCs) based anti-tumor therapies. Although ADCs have shown efficacy in cancer treatment, their application in solid tumors is hindered by their high molecular weight, poor tumor penetration, and release of cytotoxic molecules. Therefore, a recombinant immunotoxin was developed based on a shark-derived variable domain of immunoglobulin new antigen receptor (VNAR) antibody. VNARs are only one-tenth the size of IgG antibodies and possess remarkable tissue penetration capabilities and high stability. In this study, a shark VNAR phage display library was created, leading to the identification of shark VNAR-5G8 that targets TROP-2. VNAR-5G8 exhibited a high affinity and cellular internalization ability towards cells expressing high levels of TROP-2. Epitope analysis revealed that VNAR-5G8 recognizes a hidden epitope consisting of CRD and TY-1 on TROP-2. Subsequently, VNAR-5G8 was fused with a truncated form of Pseudomonas exotoxin (PE38) to create the recombinant immunotoxin (5G8-PE38), which exhibited significant anti-tumor activity in vitro and in vivo. Overall, this study highlights the promise of 5G8-PE38 as a valuable candidate for cancer therapy.

HLA evolutionary divergence (HED) informs the effect of HLA-B mismatch on outcomes after haploidentical transplantation.

Graft versus tumor relies on tumor-associated antigens (TAAs) that are presented to donor T cells via human leukocyte antigens (HLAs). The HLA evolutionary divergence (HED) between alleles of a single individual can dictate the ability to present TAAs. The impact of HED in haploidentical donor transplantation (HIDT) has not been studied. We studied the effect of HED on transplant outcomes following HIDT. We analyzed 322 consecutive recipient/donor pairs with a median follow-up of 57.2 months. Pairwise divergence of HLA class I and II showed that HLA-B, -DRB1, and -DQB1 contributing most to mean HED. The mean HED was class I 6.85 (HLA-A 7.08, -B 8.24, and -C 5.07), class II 8.58 (HLA-DRB1 10.97, -DQB1 10.06 and -DPB1 4.06). A high HED in class I mismatched recipient/donor haplotype (RD MM) was significant for worse DFS (HR 1.11, p = 0.020), and relapse (HR 1.11, p = 0.02). Also, a high HED in RD MM HLA-B haplotype had worse OS (HR 1.07, p = 0.02), DFS (HR 1.09, p = 0.002), higher relapse (HR 1.10, p = 0.003), and similar NRM to low HED. The multivariate analysis showed that high HED in RD MM HLA-B (≥7.8 vs <7.8) had worse DFS (HR 1.53, p = 0.01), higher relapse (HR 1.61, p = 0.024), and similar NRM and OS.

Synthesis and Thermodynamic Evaluation of Sialyl-Tn MUC1 Glycopeptides Binding to Macrophage Galactose-Type Lectin.

Interactions between the tumor-associated carbohydrate antigens of Mucin 1 (MUC1) and the carbohydrate-binding proteins, lectins, often lead to the creation of a pro-tumor microenvironment favoring tumor initiation, progression, metastasis, and immune evasion. Macrophage galactose binding lectin (MGL) is a C-type lectin receptor found on antigen-presenting cells that facilitates the uptake of carbohydrate antigens for antigen presentation, modulating the immune response homeostasis, autoimmunity, and cancer. Considering the crucial role of tumor-associated forms of MUC1 and MGL in tumor immunology, a thorough understanding of their binding interaction is essential for it to be exploited for cancer vaccine strategies. The synthesis of MUC1 glycopeptide models carrying a single or multiple Tn and/or sialyl-Tn antigen(s) is described. A novel approach for the sialyl-Tn threonine building block suitable for the solid phase peptide synthesis was developed. The thermodynamic profile of the binding interaction between the human MGL and MUC1 glycopeptide models was analyzed using isothermal titration calorimetry. The measured dissociation constants for the sialyl-Tn-bearing peptide epitopes were consistently lower compared to the Tn antigen and ranged from 10 μM for mono- to 1 μM for triglycosylated MUC1 peptide, respectively. All studied interactions, regardless of the glycan's site of attachment or density, exhibited enthalpy-driven thermodynamics.

Harnessing microbial antigens as cancer antigens: a promising avenue for cancer immunotherapy.

Immunotherapy has revolutionized cancer treatment by leveraging the immune system's innate capabilities to combat malignancies. Despite the promise of tumor antigens in stimulating anti-tumor immune responses, their clinical utility is hampered by limitations in eliciting robust and durable immune reactions, exacerbated by tumor heterogeneity and immune evasion mechanisms. Recent insights into the immunogenic properties of host homologous microbial antigens have sparked interest in their potential for augmenting anti-tumor immunity while minimizing off-target effects. This review explores the therapeutic potential of microbial antigen peptides in tumor immunotherapy, beginning with an overview of tumor antigens and their challenges in clinical translation. We further explore the intricate relationship between microorganisms and tumor development, elucidating the concept of molecular mimicry and its implications for immune recognition of tumor-associated antigens. Finally, we discuss methodologies for identifying and characterizing microbial antigen peptides, highlighting their immunogenicity and prospects for therapeutic application.

A pseudotyped adenovirus serotype 5 vector with serotype 49 fiber knob is an effective vector for vaccine and gene therapy applications

Adenoviruses (Ad) have demonstrated significant success as replication-deficient (RD) viral vectored vaccines, as well as broad potential across gene therapy and cancer therapy. Ad vectors transduce human cells via direct interactions between the viral fiber knob and cell surface receptors, with secondary cellular integrin interactions. Ad receptor usage is diverse across the extensive phylogeny. Commonly studied human Ad serotype 5 (Ad5), and chimpanzee Ad-derived vector “ChAdOx1” in licensed ChAdOx1 nCoV-19 vaccine, both form primary interactions with the Coxsackie and Adenovirus Receptor (CAR), which is expressed on human epithelial cells and erythrocytes. CAR usage is suboptimal for targeted gene delivery to cells with low/negative CAR expression, including human dendritic cells (DCs) and vascular smooth muscle cells (VSMCs). We evaluated the performance of a RD Ad5 vector pseudotyped with the fiber knob of human Ad serotype 49, termed Ad5/49K vector. Ad5/49K demonstrated superior transduction of murine and human DCs over Ad5, which translated into significantly increased T cell immunogenicity when evaluated in a mouse cancer vaccine model using 5T4 tumour-associated antigen. Additionally, Ad5/49K exhibited enhanced transduction of primary human VSMCs. These data highlight the potential of Ad5/49K vector for both vascular gene therapy applications and as a potent vaccine vector.

Dual Adjuvant-Loaded Peptide Antigen Self-Assembly Potentiates Dendritic Cell-Mediated Tumor Immunotherapy.

Clinical translation of current cancer vaccine research has been hampered by limited antitumor immune responses due to inefficient antigen delivery and presentation, suboptimal DC and T cell activation. Biomaterial-based nanovaccine offers targeted antigen delivery, protection from degradation in vivo, and prolonged tumor therapeutic efficacy. This study introduces a lipid-coated deoxycholic acid-survivin nanoassembly (DA-L-DSA). Survivin, overexpressed in several cancer cells and involved in cancer cell growth and immune evasion, is selected as a tumor-associated antigen. An major histocompatibility complex class I binding epitope of survivin is engineered into the nanoassembly. R848, TLR 7/8 agonist, and SD-208, TGF-beta receptor1 kinase inhibitor, are coencapsulated into the nanoassembly as potent adjuvants to boost DC maturation and enhance antigen presentation. The DA-L-DSA effectively stimulates the maturation of dendritic cells, migrates into lymph nodes, and enhances T-cell activation and Th1 response. A substantial influx of cytotoxic T lymphocytes into primary tumors is observed in a murine melanoma model and demonstrates anti-metastatic effects in a spontaneous breast cancer metastasis model. Furthermore, DA-L-DSA exhibits a remarkable synergistic effect in the combination therapy with immune checkpoint inhibitors alleviating immunosuppressive tumor microenvironment. Taken together, these findings suggest DA-L-DSA as a promising immuno-therapeutic platform that could be applicable to diverse intractable cancers.

Harnessing Dual Phototherapy and Immune Activation for Cancer Treatment: The Development and Application of BODIPY@F127 Nanoparticles.

Conventional phototherapeutic agents are typically used in either photodynamic therapy (PDT) or photothermal therapy (PTT). However, efficacy is often hindered by hypoxia and elevated levels of heat shock proteins in the tumor microenvironment (TME). To address these limitations, a formylated, near-infrared (NIR)-absorbing and heavy-atom-free Aza-BODIPY dye is presented that exhibits both type-I and type-II PDT actions with a high yield of reactive oxygen species (ROS) and manifests efficient photothermal conversion by precise adjustments to the conjugate structure and electron distribution, leading to a large amount of ROS production even under severe hypoxia. To improve biosafety and water solubility, the dye with an amphiphilic triblock copolymer (Pluronic F-127), yielding BDP-6@F127 nanoparticles (NPs) is coated. Furthermore, inspired by the fact that phototherapy triggers the release of tumor-associated antigens, a strategy that leverages potential immune activation by combining PDT/PTT with immune checkpoint blockade (ICB) therapy to amplify the systemic immune response and achieve the much-desired abscopal effect is developed. In conclusion, this study presents a promising molecular design strategy that integrates multimodal therapeutics for a precise and effective approach to cancer therapy.

Enhanced Lung Cancer Detection Using a Combined Ratio of Antigen-Autoantibody Immune Complexes against CYFRA 21-1 and p53.

The early detection of lung cancer (LC) improves patient outcomes, but current methods have limitations. Autoantibodies against tumor-associated antigens have potential as early biomarkers. This study evaluated the 9G testTM Cancer/Lung, measuring circulating complexes of two antigen-autoantibody immune complexes (AIC) against their respective free antigens (CYFRA 21-1 and p53) for LC diagnosis. We analyzed 100 LC patients and 119 healthy controls using the 9G testTM Cancer/Lung, quantifying the levels of AICs (CYFRA 21-1-Anti-CYFRA 21-1 autoantibody immune complex (CIC) and p53-Anti-p53 autoantibody immune complex (PIC)), free antigens (CYFRA 21-1 and p53), and ratios of AICs/antigens (LC index). The levels of the CICs and PICs were significantly elevated in LC compared to the controls (p < 0.0062 and p < 0.0026), while free antigens showed no significant difference. The CIC/CYFRA 21-1 and PIC/p53 ratios were also significantly higher in LC (all, p < 0.0001). The LC index, when combining both ratios, exhibited the best diagnostic performance with an area under the curve (AUC) of 0.945, exceeding individual CICs, PICs, and free antigens (AUCs ≤ 0.887). At a cut-off of 3.60, the LC index achieved 81% sensitivity and 95% specificity for LC diagnosis. It detected early-stage (Stage I-II) LC with 87.5% sensitivity, exceeding its performance in advanced stages (72.7%). The LC index showed no significant differences based on age, gender, smoking status (former, current, or never smoker), or pack years smoked. The LC index demonstrates promising potential for early LC diagnosis, exceeding conventional free antigen markers.

Combination of oncolytic Maraba virus with immune checkpoint blockade overcomes therapy resistance in an immunologically cold model of advanced melanoma with dysfunctional T-cell receptor signalling

BackgroundOver the past decade, cancer immunotherapies have revolutionized the treatment of melanoma; however, responses vary across patient populations. Recently, baseline tumor size has been identified as an independent prognostic factor...