Peptide Aggregation Induced Immunogenic Rupture (PAIIR)

Engineered probiotic Escherichia coli elicits immediate and long-term protection against influenza A virus in mice

Influenza virus infection remains a major global health problem and requires a universal vaccine with broad protection against different subtypes as well as a rapid-response vaccine to provide immediate protection in the event of an epidemic outbreak. Here, we show that intranasal administration of probiotic Escherichia coli Nissle 1917 activates innate immunity in the respiratory tract and provides immediate protection against influenza virus infection within 1 day. Based on this vehicle, a recombinant strain is engineered to express and secret five tandem repeats of the extracellular domain of matrix protein 2 from different influenza virus subtypes. Intranasal vaccination with this strain induces durable humoral and mucosal responses in the respiratory tract, and provides broad protection against the lethal challenge of divergent influenza viruses in female BALB/c mice. Our findings highlight a promising delivery platform for developing mucosal vaccines that provide immediate and sustained protection against respiratory pathogens.

Immunopeptides: immunomodulatory strategies and prospects for ocular immunity applications

Immunopeptides have low toxicity, low immunogenicity and targeting, and broad application prospects in drug delivery and assembly, which are diverse in application strategies and drug combinations. Immunopeptides are particularly important for regulating ocular immune homeostasis, as the eye is an immune-privileged organ. Immunopeptides have advantages in adaptive immunity and innate immunity, treating eye immune-related diseases by regulating T cells, B cells, immune checkpoints, and cytokines. This article summarizes the application strategies of immunopeptides in innate immunity and adaptive immunity, including autoimmunity, infection, vaccine strategies, and tumors. Furthermore, it focuses on the mechanisms of immunopeptides in mediating ocular immunity (autoimmune diseases, inflammatory storms, and tumors). Moreover, it reviews immunopeptides' application strategies and the therapeutic potential of immunopeptides in the eye. We expect the immune peptide to get attention in treating eye diseases and to provide a direction for eye disease immune peptide research.

A multifunctional CaCO3 bioreactor coated with coordination polymers enhances cancer immunotherapy

Designing effective nanomedicines to induce durable anti-tumor immunity represents a promising strategy for improving moderate immune stimulation. In this study, we engineered a multifunctional nanoreactor (named SCGFP NPs) for remodeling the tumor microenvironment (TME) to improve the therapeutic efficacy of immunotherapy. The core of SCGFP NPs consists of CaCO3 loaded with SN38, prepared by the gas diffusion method, and coated with a significant amount of gallic acid-Fe3+-PEG coordination polymer on the surface. In the acidic TME, SCGFP NPs explosively release exogenous Ca2+ and SN38. The SN38-induced intracellular Ca2+ accumulation and exogenous Ca2+ synergistically trigger immunogenic cell death (ICD) through sustained Ca2+ overload. The ablation of tumors with high-intensity photothermal therapy (PTT) by near-infrared (NIR) irradiation of GA-Fe3+ induces tumor cell necrosis, further enhancing ICD activation. Additionally, SN38 upregulates PD-L1, amplifying tumor responsiveness to immune checkpoint inhibitors (ICIs). This study indicates that SCGFP NPs, through the integration of a trimodal therapeutic strategy, hold enormous potential for various types of tumor immunotherapy through distinct mechanisms or synergistic effects.

Peptide aggregation-induced immunogenic cell death in a breast cancer spheroid model

Utilizing multicellular aggregates (spheroids) for in vitro cancer research offers a physiologically relevant model that closely mirrors the intricate tumor microenvironment, capturing properties of solid tumors such as cell interactions and drug resistance. In this research, we investigated the Peptide-Aggregation Induced Immunogenic Response (PAIIR), an innovative method employing engineered peptides we designed specifically to induce immunogenic cell death (ICD). We contrasted PAIIR-induced ICD with standard ICD and non-ICD inducer chemotherapeutics within the context of three-dimensional breast cancer tumor spheroids. Our findings reveal that PAIIR outperforms traditional chemotherapeutics in its efficacy to stimulate ICD. This is marked by the release of key damage-associated molecular patterns (DAMPs), which bolster the phagocytic clearance of dying cancer cells by dendritic cells (DCs) and, in turn, activate powerful anti-tumor immune responses. Additionally, we observed that PAIIR results in elevated dendritic cell activation and increased antitumor cytokine presence. This study not only showcases the utility of tumor spheroids for efficient high-throughput screening but also emphasizes PAIIR's potential as a formidable immunotherapeutic strategy against breast cancer, setting the stage for deeper exploration and potential clinical implementation.

Biomaterials That Induce Immunogenic Cell Death

The immune system takes part in most physiological and pathological processes of the body, including the occurrence and development of cancer. Immunotherapy provides a promising modality for inhibition and even the cure of cancer. During immunotherapy, the immunogenic cell death (ICD) of tumor cells induced by chemotherapy, radiotherapy, phototherapy, bioactive materials, and so forth, triggers a series of cellular responses by causing the release of tumor-associated antigens and damage-associated molecular patterns, which ultimately activate innate and adaptive immune responses. Among them, the ICD-induced biomaterials attract increasing conditions as a benefit of biosafety and multifunctional modifications. This Review summarizes the research progress in biomaterials for inducing ICD via triggering endoplasmic reticulum oxidative stress, mitochondrial dysfunction, and cell membrane rupture and discusses the application prospects of ICD-inducing biomaterials in clinical practice for cancer immunotherapy.

Controllable membrane damage by tunable peptide aggregation with albumin

Aggregation of otherwise soluble proteins into amyloid structures is a hallmark of many disorders, such as Alzheimer's and Parkinson's disease. There is an increasing evidence that the small aggregations, instead of ordered fibrillar aggregates, are the main structures causing toxicity. However, the studies on the small aggregation phase are limited due to the variety of structures and the complexity of the physiological environment. Here, we showed an engineered co-assembling oppositely charged amyloid-like peptide pair ([II]) as a simple tool to establish methodologies to study the mechanism and kinetics of aggregation and relate its aggregation to toxicity. The toxicity mechanism of [II] is through cell membrane damage and stress, shown with YAP and eIF2α, as in the amyloid protein-initiated diseases. Albumin is demonstrated as an extrinsic and physiologically relevant molecule in controlling the aggregation lag time and toxicity of [II]. This study represents a molecular engineering strategy to create simplistic molecular tools for establishing methodologies to study the aggregation process and kinetics of amyloid-like proteins in various conditions. Understanding the nature of protein aggregation kinetics and linking them to their biological functions through engineered peptides paves the way for future designs and drug development applications.

Self-Splittable Transcytosis Nanoraspberry for NIR-II Photo-Immunometabolic Cancer Therapy in Deep Tumor Tissue

Cancer photo-immunotherapy (CPIT) as an ideal strategy can rapidly release hostile signals by appropriate dosage of focal laser irradiation to unmask primary tumor immunogenicity and can activate adaptive immunity to control distant metastases. However, many factors, including disordered immunometabolism, poor penetration of photothermal agents and immuno-regulators, inadequate laser penetration into the deep tumor region, restrict the therapeutic outcomes of CPIT. Here, a second near-infrared window (NIR-II) photo-immunometabolic cancer therapy (PICT) by a programmed raspberry-structured nanoadjuvant (PRNMT ) is presented that can potentiates efficient immunogenic cell death (ICD) in deep tumor tissue and alleviates immunometabolic disorder. The PRNMT is architected through self-assembly of indoleamine 2,3-dioxygenase 1 (IDO-1) inhibitor modified small-sized CuS nanoparticles (CuS5 ) and tumor microenvironment (TME) responsive cationized polymeric matrix. The TME can trigger the splitting and surface cationization of PRNMT into small cationized CuS5 that feature high transcytosis potential and TME immunometabolic regulation. Upon NIR-II irradiation, CuS5 induce homogeneous ICD and release immunometabolic regulator in deep tumor tissues, which ameliorates IDO-1 mediated immunometabolic disorder and further suppresses regulatory T cells infiltration. PRNMT mediated PICT effectively delays the primary murine mammary carcinoma 4T1 tumor growth and inhibits the lethal pulmonary metastasis in combination with programmed cell death protein 1 (PD1) blockade.