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As the prevalence of viral infection in body, human T‐cell leukemia virus type 1 (HTLV‐1) is receiving increasing attention. Research on the corresponding virus models is of great significance to tackle the challenges of understanding HTLV‐1 development and treatment. This paper focuses on the dynamic analysis for a stochastic model with nonlinear cytotoxic T lymphocyte (CTL) response, which is driven by Ornstein–Uhlenbeck (OU) process to model the progression of HTLV‐1 in vivo. Rich dynamic behaviors such as the extinction of infected CD4+ T cells (ITCs), stationary distribution (SD), probability density, and finite‐time stability (FTS) of the model are established to reveal the interaction of cell populations. The optimal therapeutic strategy based on the cost‐benefit viewpoint is further obtained. Finally, illustrative numerical simulations are represented to corroborate the effectiveness of treatment and the ambient perturbation's impact that strengthening the noise strength can lead to rapid virus clearance. [ABSTRACT FROM AUTHOR]

This paper explores the dynamics analysis of a human immunodeficiency virus (HIV) model with saturated cytotoxic T lymphocyte (CTL) immune response and Beddington–DeAngelis infection rate. There are two time delays in the model to describe the time needed for infection of cell and CTL immune response generation, respectively. We obtain two thresholds and three possible equilibria from the model. By analyzing the corresponding characteristic equations, we study the stabilities of equilibrium and the effect of delays on CTL immune response. The results indicate that when immune delay is present, the steady state of equilibrium is disrupted and leads to a Hopf bifurcation. Finally, we use sensitivity analyses to show the effect of parameters on thresholds and numerical simulations to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

Immunotherapy using immune checkpoint inhibitors (ICIs) has shown superior efficacy compared with conventional chemotherapy in certain cancer types, establishing immunotherapy as the fourth standard treatment alongside surgical intervention, chemotherapy, and radiotherapy. In cancer immunotherapy employing ICIs, CD8‐positive cytotoxic T lymphocytes are recognized as the primary effector cells. For effective clinical outcomes, it is essential that the targeted cancer cells express HLA class I molecules to present antigenic peptides derived from the tumor. However, cancer cells utilize various mechanisms to downregulate or lose HLA class I molecules from their surface, resulting in evasion from immune surveillance. Correlations between prognosis and the integrity of HLA class I molecules expressed by cancer cells have been consistently found across different types of cancer. This paper provides an overview of the regulatory mechanisms of HLA class I molecules and their role in cancer immunotherapy, with a particular emphasis on the significance of utilizing pathological tissues to evaluate HLA class I molecules expressed in cancer cells. [ABSTRACT FROM AUTHOR]

According to the latest evidence, the microbial metabolite Urolithin A (UA), known for its role in promoting cellular health, modulates CD8+ T cell‐mediated antitumor activity. However, the direct target protein of UA and its underlying mechanism remains unclear. Here, this research identifies ERK1/2 as the specific target crucial for UA‐mediated CD8+ T cell activation. Even at low doses, UA markedly enhances the persistence and effector functions of primary CD8+ cytotoxic T lymphocytes (CTLs) and human chimeric antigen receptor (CAR) T cells both in vitro and in vivo. Mechanistically, UA interacts directly with ERK1/2 kinases, enhancing their activation and subsequently facilitating T cell activation by engaging ULK1. The UA‐ERK1/2‐ULK1 axis promotes autophagic flux in CD8+ CTLs, enhancing cellular metabolism and maintaining reactive oxygen species (ROS) levels, as evidenced by increased oxygen consumption and extracellular acidification rates. UA‐treated CD8+ CTLs also display elevated ATP levels and enhanced spare respiratory capacity. Overall, UA activates ERK1/2, inducing autophagy and metabolic adaptation, showcasing its potential in tumor immunotherapy and interventions for diseases involving ERKs. [ABSTRACT FROM AUTHOR]

Personalized cancer vaccines based on resected tumors from patients is promising to address tumor heterogeneity to inhibit tumor recurrence or metastasis. However, it remains challenge to elicit immune activation due to the weak immunogenicity of autologous tumor antigens. Here, a hybrid membrane cancer vaccine is successfully constructed by membrane fusion to enhance adaptive immune response and amplify personalized immunotherapy, which formed a codelivery system for autologous tumor antigens and immune adjuvants. Briefly, the functional hybrid vesicles (HM‐NPs) are formed by hybridizing ginseng‐derived extracellular vesicles‐like particles (G‐EVLPs) with the membrane originated from the resected autologous tumors. The introduction of G‐EVLPs can enhance the phagocytosis of autologous tumor antigens by dendritic cells (DCs) and facilitate DCs maturation through TLR4, ultimately activating tumor‐specific cytotoxic T lymphocytes (CTLs). HM‐NPs can indeed strengthen specific immune responses to suppress tumors recurrence and metastasis including subcutaneous tumors and orthotopic tumors. Furthermore, a long‐term immune protection can be obtained after vaccinating with HM‐NPs, and prolonging the survival of animals. Overall, this personalized hybrid autologous tumor vaccine based on G‐EVLPs provides the possibility of mitigating tumor recurrence and metastasis after surgery while maintaining good biocompatibility. [ABSTRACT FROM AUTHOR]

This article explores the molecular characteristics and immune microenvironments of secondary radiation-exposed rectal cancers (SRCs) compared to primary rectal cancers (PRCs). The study used single-cell transcriptomic sequencing to analyze the cell type-specific profiles of 18 SRCs and identified distinct differences in copy number variation and immune cell composition between SRCs and PRCs. The findings suggest that oncogene amplification and the activation of Treg cells may promote the progression of SRCs, while the emergence of neutrophils and activation of macrophages contribute to the immune microenvironment of SRCs. The study provides valuable insights into the tumorigenesis of SRCs and potential therapeutic strategies. [Extracted from the article]

Immunotherapy targeting PD‐L1 is still ineffective for a wide variety of tumors with high unpredictability. Deploying combined immunotherapy with alternative targeting is practical to overcome this therapeutic resistance. Here, the deficiency of serine‐threonine kinase STK24 is observed in tumor cells causing substantial attenuation of tumor growth in murine syngeneic models, a process relying on cytotoxic CD8+ T and NK cells. Mechanistically, STK24 in tumor cells associates with and directly phosphorylates AKT at Thr21, which promotes AKT activation and subsequent PD‐L1 induction. Deletion or inhibition of STK24, by contrast, blocks IFN‐γ‐mediated PD‐L1 expression. Various murine models indicate that in vivo silencing of STK24 can significantly enhance the efficacy of the anti‐PD‐1 blockade strategy. Elevated STK24 levels are observed in patient specimens in multiple tumor types and inversely correlated with intratumoral infiltration of cytotoxic CD8+ T cells and with patient survival. The study collectively identifies STK24 as a critical modulator of antitumor immunity, which engages in AKT and PD‐L1/PD‐1 signaling and is a promising target for combined immunotherapy. [ABSTRACT FROM AUTHOR]

The liver is the most tolerogenic of transplanted organs. However, the mechanisms underlying liver transplant tolerance are not well understood. The comparison between liver transplantation tolerance and heart/kidney transplantation rejection will deepen our understanding of tolerance and rejection in solid organs. Here, we built a mouse model of liver, heart and kidney allograft and performed single-cell RNA sequencing of 66,393 cells to describe the cell composition and immune cell interactions at the early stage of tolerance or rejection. We also performed bulk RNA-seq of mouse liver allografts from Day 7 to Day 60 posttransplantation to map the dynamic transcriptional variation in spontaneous tolerance. The transcriptome of lymphocytes and myeloid cells were characterized and compared in three types of organ allografts. Cell-cell interaction networks reveal the coordinated function of Kupffer cells, macrophages and their associated metabolic processes, including insulin receptor signalling and oxidative phosphorylation in tolerance induction. Cd11b+ dendritic cells (DCs) in liver allografts were found to inhibit cytotoxic T cells by secreting anti-inflammatory cytokines such as Il10. In summary, we profiled single-cell transcriptome analysis of mouse solid organ allografts. We characterized the immune microenvironment of mouse organ allografts in the acute rejection state (heart, kidney) and tolerance state (liver). [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer‐related death worldwide. Hepatectomy remains the first‐line treatment for patients with resectable HCC. However, the reported recurrence rate of HCC at 5 years after surgery is between 50% and 70%. Tumor‐related factors, including tumor size, number and differentiation, and underlying liver disease are well‐known risk factors for recurrence after treatment. In addition to tumor‐related factors, ever‐increasing amounts of studies are finding that the tumor microenvironment also plays an important role in the recurrence of HCC, including systemic inflammatory response and immune regulation. Based on this, some inflammatory and immune markers were used in predicting postoperative cancer recurrence. These include neutrophil‐to‐lymphocyte ratio, platelet‐to‐lymphocyte ratio, cytotoxic T cells, and regulatory T cells, among others. In this review, we summarized the inflammatory and immune markers that affect recurrence after HCC resection in order to provide direction for adjuvant therapy after HCC resection and ultimately achieve the goal of reducing recurrence. [ABSTRACT FROM AUTHOR]