The multifaceted role of CD4(+) T cells in CD8(+) T cell memory

Maternal probiotic exposure enhances CD8 T cell protective neonatal immunity and modulates offspring metabolome to control influenza virus infection

Maternal gut microbiota composition contributes to the status of the neonatal immune system and could influence the early life higher susceptibility to viral respiratory infections. Using a novel protocol of murine maternal probiotic supplementation, we report that perinatal exposure to Lacticaseibacillus rhamnosus (L.rh) or Bifidobacterium animalis subsp. lactis (B.lac) increases the influenza A/PR8 virus (IAV) clearance in neonates. Following either supplementation, type 1 conventional dendritic cells (cDC1) were amplified in the lymph nodes leading to an enhanced IAV antigen-experienced IFN-γ producing effector CD8 T cells in neonates and IAV-specific resident memory CD8 T cells in adulthood. This was compatible with a higher protection of the offspring upon a secondary infection. Interestingly, only mice born to L.rh supplemented mothers further displayed an increased activation of IFN-γ producing virtual memory CD8 T cells and a production of IL-10 by CD4 and CD8 T cells that could explain a better control of the lung damages upon infection. In the offspring and the mothers, no disturbance of the gut microbiota was observed but, as analyzed through an untargeted metabolomic approach, both exposures modified neonatal plasma metabolites. Among them, we further demonstrated that genistein and 3-(3-hydroxyphenyl)propionic acid recapitulate viral clearance or cDC1 activation in neonates exposed to IAV. We conclude that maternal L.rh or B.lac supplementation confers the neonates specific metabolomic modulations with a better CD8 T cell-mediated immune protection against IAV infection.

Engineered bacterial membrane biomimetic covalent organic framework as nano-immunopotentiator for cancer immunotherapy

The cellular uptake and tissue dispersion efficiency of nanomedicines are crucial for realizing their biological functionality. As a cutting-edge category of nanomedicine, covalent organic frameworks (COFs)-based photosensitizers, have been extensively employed in cancer phototherapy in recent years. However, the inherent aggregation tendency of COFs hinders their uptake by tumor cells and dispersion within tumor tissues, thereby limiting their therapeutic efficacy. In this study, we employed Fusobacterium nucleatum (F.n.), a prevalent intratumoral bacterium, to construct a bacterium membrane-wrapped COF, COF-306@FM, which is readily taken up by cancer cells and uniformly dispersed within tumor tissues. Meanwhile, the F.n. membrane can also serve as an immune adjuvant to warm up the "cold" tumor immune microenvironment by enhancing the CD8+ T and B cells infiltration, and inducing the formation of tumor-located tertiary lymphoid structures. Consequently, the response rate of αPD-L1 immunotherapy was drastically promoted to efficiently prevent tumor metastasis and recurrence, causing 84.6 % distant tumor inhibition and complete suppression of tumor metastasis. In summary, this innovative approach not only enhances the therapeutic potential of COFs but also opens up new avenues for integrating microbial and nanotechnological strategies in cancer treatment.

Dissecting the immune response of CD4+ T cells in Alzheimer's disease

The formation of amyloid-β (Aβ) plaques is a neuropathological hallmark of Alzheimer's disease (AD), however, these pathological aggregates can also be found in the brains of cognitively unimpaired elderly population. In that context, individual variations in the Aβ-specific immune response could be key factors that determine the level of Aβ-induced neuroinflammation and thus the propensity to develop AD. CD4+ T cells are the cornerstone of the immune response that coordinate the effector functions of both adaptive and innate immunity. However, despite intensive research efforts, the precise role of these cells during AD pathogenesis is still not fully elucidated. Both pathogenic and beneficial effects have been observed in various animal models of AD, as well as in humans with AD. Although this functional duality of CD4+ T cells in AD can be simply attributed to the vast phenotype heterogeneity of this cell lineage, disease stage-specific effect have also been proposed. Therefore, in this review, we summarized the current understanding of the role of CD4+ T cells in the pathophysiology of AD, from the aspect of their antigen specificity, activation, and phenotype characteristics. Such knowledge is of practical importance as it paves the way for immunomodulation as a therapeutic option for AD treatment, given that currently available therapies have not yielded satisfactory results.

Advances and Challenges in Aeromonas hydrophila Vaccine Development: Immunological Insights and Future Perspectives

Aeromonas hydrophila presents a significant threat to global aquaculture due to its ability to infect freshwater and marine fish species, leading to substantial economic losses. Effective mitigation methods are essential to address these challenges. Vaccination has emerged as a promising strategy to reduce A. hydrophila infections; however, it faces several obstacles, including variability in immune responses, pathogen diversity, and environmental factors affecting vaccine efficacy. To enhance vaccine performance, researchers focus on adjuvants to boost immune responses and develop multivalent vaccines targeting multiple A. hydrophila strains. Tailoring vaccines to specific environmental conditions and optimizing vaccination schedules can further address the challenges posed by pathogen diversity and variable immune responses. This review provides an in-depth analysis of the immunological hurdles associated with A. hydrophila vaccine development. Current vaccine types-live attenuated, inactivated, subunit, recombinant, and DNA-exhibit diverse mechanisms for stimulating innate and adaptive immunity, with varying levels of success. Key focus areas include the potential of advanced adjuvants and nanoparticle delivery systems to overcome existing barriers. The review also highlights the importance of understanding host-pathogen interactions in guiding the development of more targeted and effective immune responses in fish. Complementary approaches, such as immunostimulants, probiotics, and plant-based extracts, are explored as adjuncts to vaccination in aquaculture health management. Despite notable progress, challenges remain in translating laboratory innovations into scalable, cost-effective solutions for aquaculture. Future directions emphasize the integration of advanced genomic and proteomic tools to identify novel antigen candidates and the need for industry-wide collaborations to standardize vaccine production and delivery. Addressing these challenges can unlock the potential of innovative vaccine technologies to safeguard fish health and promote sustainable aquaculture practices globally.

IL-4 induces CD22 expression to restrain the effector program of virtual memory T cells

Parasitic helminths induce the production of interleukin-4 (IL-4), which causes the expansion of virtual memory CD8+ T cells (TVM cells), a cell subset that contributes to the control of coinfection with intracellular pathogens. However, the mechanisms regulating IL-4-dependent TVM cell activation and expansion remain ill defined. Here, we used single-cell RNA sequencing of CD8+ T cells to identify pathways that control IL-4-dependent TVM cell responses. Gene signature analysis of CD8+ T cells identified a cell cluster marked by CD22, a canonical regulator of B cell activation, as a selective surface marker of IL-4-induced TVM cells. CD22+ TVM cells were enriched for interferon-γ and granzyme A and retained a diverse TCR repertoire while enriched in self-reactive CDR3 sequences. CD22 intrinsically regulated the IL-4-induced CD8+ T cell effector program, resulting in reduced responsiveness of CD22+ TVM cells and regulatory functions to infection and inflammation. Thus, helminth-induced IL-4 drives the expansion and activation of TVM cells that is counterinhibited by CD22.

Restoring tumor antigenicity activates the "bystander" T cell immune cycle

Tumor-specific T cells play a crucial role in tumor immunity. However, these cells are often scarce and functionally exhausted within the tumor microenvironment (TME), leading to the limited efficacy of immunotherapy in many cancer patients. In contrast, increasing evidence suggests that the TME is rich in "bystander" T cells (TBYS), most of which are virus-specific and unrelated to the tumor. These TBYS cells retain functional memory characteristics and the potential to kill tumor cells. To utilize TBYS cells in the TME for tumor elimination, we designed an intracellular delivery system, ASCP, encoding a TBYS epitope to redirect tumor cell antigen specificity toward pre-existing TBYS cells, resulting in effective tumor inhibition in multiple preclinical models. The ASCP-antigen peptide strategy restores the antigenicity of tumor cells and induces epitope spreading of tumor antigens, thereby eliciting more diverse tumor-specific T cell responses. Remarkably, this strategy incorporates MHC-II epitopes containing unnatural amino acids (p-nitrophenylalanine, termed NiraTh), which stimulate CD4+ T cell-mediated immunity and assist CD8+ T cells in clearing tumors. Overall, the ASCP-mediated tumor antigen reprogramming strategy provides important insights for cancer immunotherapy in populations with a history of common viral infections.

Glucose Metabolism Reprogramming of Immune Cells in the Microenvironment of Pancreatic and Hepatobiliary Cancers

BACKGROUND AND AIM

Pancreatic and hepatobiliary cancers are increasing in prevalence and contribute significantly to cancer-related mortality worldwide. Emerging therapeutic approaches, particularly immunotherapy, are gaining attention for their potential to harness the patient's immune system to combat these tumors. Understanding the role of immune cells in the tumor microenvironment (TME) and their metabolic reprogramming is key to developing more effective treatment strategies. This review aims to explore the relationship between immune cell function and glucose metabolism in the TME of pancreatic and hepatobiliary cancers.

METHODS

This review synthesizes current research on the metabolic adaptations of immune cells, specifically focusing on glucose metabolism within the TME of pancreatic and hepatobiliary cancers. We examine the mechanisms by which immune cells influence tumor progression through metabolic reprogramming and how these interactions can be targeted for therapeutic purposes.

RESULTS

Immune cells in the TME undergo significant metabolic changes, with glucose metabolism playing a central role in modulating immune responses. These metabolic shifts not only affect immune cell function but also influence tumor behavior and progression. The unique metabolic features of immune cells in pancreatic and hepatobiliary cancers provide new opportunities for targeting immune responses to combat these malignancies more effectively.

CONCLUSION

Understanding the complex relationship between immune cell glucose metabolism and tumor progression in the TME of pancreatic and hepatobiliary cancers offers promising therapeutic strategies. By modulating immune responses through targeted metabolic interventions, it may be possible to improve the efficacy of immunotherapies and better combat these aggressive cancers.

ETV7 limits the antiviral and antitumor efficacy of CD8+ T cells by diverting their fate toward exhaustion

Terminal exhaustion is a critical barrier to antitumor immunity. By integrating and analyzing single-cell RNA-sequencing and single-cell assay for transposase-accessible chromatin with sequencing data, we found that ETS variant 7 (ETV7) is indispensable for determining CD8+ T cell fate in tumors. ETV7 introduction drives T cell differentiation from memory to terminal exhaustion, limiting antiviral and antitumor efficacy in male mice. Mechanistically, ETV7 acts as a central transcriptional node by binding to specific memory genes and exhaustion genes and functionally skewing these transcriptional programs toward exhaustion. Clinically, ETV7 expression is negatively correlated with progression and responsiveness to immune checkpoint blockade in various human cancers. ETV7 depletion strongly enhances the antitumor efficacy of CD8+ T cells and engineered chimeric antigen receptor T cells in solid tumors. Thus, these findings demonstrate a decisive role for ETV7 in driving CD8+ T cell terminal exhaustion and reveal that ETV7 may be a promising target and biomarker for improving the efficacy of cancer immunotherapy.

Immune checkpoints in B-cell Lymphoma: Still an Unmet challenge from Basic research to clinical practice

In the last decade, advancements in immunotherapy knowledge have highlighted CTLA-4, PD-1, LAG-3, TIM-3, and TIGIT, decisive immune checkpoints exhibiting within the tumor microenvironment (TME), as fundamental objects for cancer immunotherapy. The widespread clinical use of immune checkpoint inhibitors (ICls), employing PD-1/PD-L1 or CTLA-4 antibodies to obstruct crucial checkpoint regulators, is noted in treating B-cell lymphoma patients. Nevertheless, the prolonged advantages of the currently employed treatments against CTLA-4, PD-1, and PD-L1 are uncommon among patients. Thus, recent focus has been progressively moved to additional immune checkpoints on T cells, like LAG-3, TIM-3, and TIGIT, which are now seen as reassuring targets for treatment and broadly acknowledged. There are several types of immunecheckpoint molecules expressed by T cells, and inhibitors targeting immune checkpoints can revive and amplify the immune response of T lymphocytes against tumors, a crucial aspect in lymphoma therapy. However, there is little knowledge about their regulation. Herein, we discuss the anti-tumor effects and functions of ICIs in controlling T-cell activity, as well as the progress in combined application with other immunotherapies.

Impact of a Concurrent Respiratory Virus Infection on the Clinical Presentation and Response to Initial Treatment of Kawasaki Disease: A Single-Center Observational Study

Background: The impact of respiratory viral infections associated with Kawasaki Disease (KD) cases on KD's clinical presentation and initial response to treatment has not been clearly determined. Objective: This study aimed to evaluate respiratory viral infections using FilmArray Respiratory Panel (FARP) testing and analyze the effect of the concurrent presence of pathogens on clinical presentations of KD. Methods: Between January 2021 and June 2023, we conducted a retrospective, single-center observational study of 105 Japanese children with KD. KD was diagnosed and treated according to RAISE study guidelines, and the cases' clinical information was assessed. FARP testing was performed in 71 out of 105 KD cases with fever and/or respiratory symptoms. Results: In 38 (53.5%) out of 71 cases, at least one virus was detected. The FARP-positive cases tended to have a higher frequency of Kobayashi scores (K-scores) ≥ 5 than the negative cases (42.1% vs. 21.2%), and lower initial treatment failure (7.89% vs. 21.2%). The most common virus detected was rhino/enterovirus (RV/EV: 27 cases), followed by seven cases of respiratory syncytial virus (RSV). RV/EV-positive KD cases did not differ significantly in their clinical data or the frequency of K-scores ≥ 5, and RSV-positive cases showed significantly elevated liver enzyme (AST:59 U/L (43.5-150.5) vs. 35 U/L (27-41), ALT:40 U/L (28.5-244.5) vs. 18 U/L (14-27)) and CRP levels (12 mg/dL (7.3-14.2) vs. 6.5 mg/dL (4.1-8.5)), and an increased frequency of K-scores ≥ 5 (71.4% vs. 21.2%) compared to FARP-negative cases. KD cases that were also RSV-positive or RV/EV-positive showed favorable responses to initial treatments. Conclusions: Concurrent respiratory virus infection could affect the clinical manifestation and initial treatment response of KD.

Identification of novel Kv1.3 channel-interacting proteins using proximity labelling in T-cells

Potassium channels regulate membrane potential, calcium flux, cellular activation and effector functions of adaptive and innate immune cells. The voltage-activated Kv1.3 channel is an important regulator of T cell-mediated autoimmunity and microglia-mediated neuroinflammation. Kv1.3 channels, via protein-protein interactions, are localized with key immune proteins and pathways, enabling functional coupling between K+ efflux and immune mechanisms. To gain insights into proteins and pathways that interact with Kv1.3 channels, we applied a proximity-labeling proteomics approach to characterize protein interactors of the Kv1.3 channel in activated T-cells. Biotin ligase TurboID was fused to either N or C termini of Kv1.3, stably expressed in Jurkat T cells and biotinylated proteins in proximity to Kv1.3 were enriched and quantified by mass spectrometry. We identified over 1,800 Kv1.3 interactors including known interactors (beta-integrins, Stat1) although majority were novel. We found that the N-terminus of Kv1.3 preferentially interacts with protein synthesis and protein trafficking machinery, while the C-terminus interacts with immune signaling and cell junction proteins. T-cell Kv1.3 interactors included 335 cell surface, T-cell receptor complex, mitochondrial, calcium and cytokine-mediated signaling pathway and lymphocyte migration proteins. 178 Kv1.3 interactors in T-cells also represent genetic risk factors of T cell-mediated autoimmunity, including STIM1, which was further validated using co-immunoprecipitation. Our studies reveal novel proteins and molecular pathways that interact with Kv1.3 channels in adaptive (T-cell) and innate immune (microglia), providing a foundation for how Kv1.3 channels may regulate immune mechanisms in autoimmune and neurological diseases.

Cellular and humoral immune responses in cats vaccinated with feline herpesvirus 1 modified live virus vaccine

Feline herpesvirus 1 (FHV-1) is an important pathogen causing infectious rhinotracheitis in felids, mainly infecting the upper respiratory tract and conjunctiva. Multiple vaccines are available to prevent FHV-1 infection, and the antibody levels are always used to evaluate their effectiveness. However, the cellular immunity response following immunization in cats remains unclear. This study investigated the immune responses (humoral and cellular) in cats immunized with the FHV-1 modified live virus vaccine. The results indicated that vaccination significantly reduced clinical signs, and antibody levels, including virus-neutralizing (VN) antibodies and immunoglobulin G (IgG), in the vaccine group were higher than those in the control groups. Additionally, the vaccine significantly increased cytokine secretion, indicating Th1-type cellular immune responses in cats. Moreover, cellular immune-related indicators, such as CD8+ T cells, CD4+ T cells, and interferon-gamma levels, were inversely correlated with clinical signs post-challenge by FHV-1 in vaccinated cats, highlighting its crucial role in protecting cats against FHV-1 infection. In summary, this study demonstrated the importance of cellular immune responses in protecting cats from FHV-1 infection after vaccination.

Anti-CTLA-4 generates greater memory response than anti-PD-1 via TCF-1

The effects of T cell differentiation arising from immune checkpoint inhibition targeting cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1) on the immunological memory response remain unclear. Our investigation into the effects of anti-CTLA-4 and anti-PD-1 on memory T cell formation in mice reveals that memory T cells generated by anti-CTLA-4 exhibit greater expansion, cytokine production, and antitumor activity than those from anti-PD-1. Notably, anti-CTLA-4 preserves more T cell factor-1 (TCF-1)+ T cells during priming, while anti-PD-1 leads to more thymocyte selection-associated high mobility group box (TOX)+ T cells. Experiments using conditional Tcf7- or Tox-knockout mice highlight that TCF-1 is essential for the memory response generated by anti-CTLA-4, whereas TOX deletion alone in T cells has no effect on the response to anti-PD-1. Deepening our understanding of how checkpoint inhibition affects memory response is crucial for advancing our understanding of the enduring impacts of these immunotherapies on the immune system.

Ketogenic diet and cancer: multidimensional exploration and research

The ketogenic diet (KD) has attracted attention in recent years for its potential anticancer effects. KD is a dietary structure of high fat, moderate protein, and extremely low carbohydrate content. Originally introduced as a treatment for epilepsy, KD has been widely applied in weight loss programs and the management of metabolic diseases. Previous studies have shown that KD can potentially inhibit the growth and spread of cancer by limiting energy supply to tumor cells, thereby inhibiting tumor angiogenesis, reducing oxidative stress in normal cells, and affecting cancer cell signaling and other processes. Moreover, KD has been shown to influence T-cell-mediated immune responses and inflammation by modulating the gut microbiota, enhance the efficacy of standard cancer treatments, and mitigate the complications of chemotherapy. However, controversies and uncertainties remain regarding the specific mechanisms and clinical effects of KD as an adjunctive therapy for cancer. Therefore, this review summarizes the existing research and explores the intricate relationships between KD and cancer treatment.

scImmOmics: a manually curated resource of single-cell multi-omics immune data

Single-cell sequencing technology has enabled the discovery and characterization of subpopulations of immune cells with unique functions, which is critical for revealing immune responses under healthy or disease conditions. Efforts have been made to collect and curate single-cell RNA sequencing (scRNA-seq) data, yet an immune-specific single-cell multi-omics atlas with harmonized metadata is still lacking. Here, we present scImmOmics (https://bio.liclab.net/scImmOmics/home), a manually curated single-cell multi-omics immune database constructed based on high-quality immune cells with known immune cell labels. Currently, scImmOmics documents >2.9 million cell-type labeled immune cells derived from seven single-cell sequencing technologies, involving 131 immune cell types, 47 tissues and 4 species. To ensure data consistency, we standardized the nomenclature of immune cell types and presented them in a hierarchical tree structure to clearly describe the lineage relationships within the immune system. scImmOmics also provides comprehensive immune regulatory information, including T-cell/B-cell receptor sequencing clonotype information, cell-specific regulatory information (e.g. gene/chromatin accessibility/protein/transcription factor states within known cell types, cell-to-cell communication and co-expression networks) and immune cell responses to cytokines. Collectively, scImmOmics is a comprehensive and valuable platform for unraveling the heterogeneity and diversity of immune cells and elucidating the specific regulatory mechanisms at the single-cell level.

Distinct Requirements for CD4+ T Cell Help for Immune Responses Induced by mRNA and Adenovirus-Vector SARS-CoV-2 Vaccines

CD4+ T cells have been established as central orchestrators of cellular and humoral immune responses to infection or vaccination. However, the need for CD4+ T cell help to generate primary CD8+ T cell responses is variable depending on the infectious agent or vaccine and yet consistently required for the recall of CD8+ T cell memory responses or antibody responses. Given the deployment of new vaccine platforms such as nucleoside-modified mRNA vaccines, we sought to elucidate the requirement for CD4+ T cell help in the induction of cellular and antibody responses to mRNA and adenovirus (Ad)-vectored vaccines against SARS-CoV-2. Using antibody-mediated depletion of CD4+ T cells in a mouse immunization model, we observed that CD4+ T cell help was dispensable for both primary and secondary CD8+ T cell responses to the BNT162b2 and mRNA-1273 mRNA vaccines but required for the AZD1222 Ad-vectored vaccine. Nonetheless, CD4+ T cell help was needed by both mRNA and Ad-vectored vaccine platforms for the generation of antibodies, demonstrating the centrality of CD4+ T cells in vaccine-induced protective immunity against SARS-CoV-2. Ultimately, this highlights the shared and distinct regulation of humoral and cellular responses induced by these vaccine platforms.

Receptor Binding Domain-Specific B Cell Memory Responses Among Individuals Vaccinated Against SARS-CoV-2

Background: The COVID-19 pandemic prompted unprecedented vaccine development efforts against SARS-CoV-2. India, which was one of the countries most impacted by COVID-19, developed its indigenous vaccine in addition to utilizing the ones developed by other countries. While antibody levels and neutralizing antibody titres are considered initial correlates of immune protection, long-term protection from the pathogen relies on memory B and T cells and their recall responses. In this regard, global research has primarily focused on mRNA-based vaccines. The studies on immune memory response, particularly B cell memory response induced by the vaccines given to Indians, remain relatively obscure. Methods: We assessed Receptor Binding Domain-specific memory B cells in the peripheral circulation and their ability to secrete antigen-specific antibodies among Indians vaccinated with Covaxin (BBV152), Covishield (AZD1222), Corbevax (BECOV2D), and Sputnik Light, as well as unvaccinated individuals. Results: Corbevax and Sputnik Light conferred better antibody-secreting cell (ASC) responses over time compared to other groups. Conclusions: These findings contribute to our understanding of vaccine-induced immune memory in the Indian population; providing insights that could inform future vaccine strategies.

Plasticity and Tumor Microenvironment in Pancreatic Cancer: Genetic, Metabolic, and Immune Perspectives

Cancer has long been believed to be a genetic disease caused by the accumulation of mutations in key genes involved in cellular processes. However, recent advances in sequencing technology have demonstrated that cells with cancer driver mutations are also present in normal tissues in response to aging, environmental damage, and chronic inflammation, suggesting that not only intrinsic factors within cancer cells, but also environmental alterations are important key factors in cancer development and progression. Pancreatic cancer tissue is mostly comprised of stromal cells and immune cells. The desmoplasmic microenvironment characteristic of pancreatic cancer is hypoxic and hypotrophic. Pancreatic cancer cells may adapt to this environment by rewiring their metabolism through epigenomic changes, enhancing intrinsic plasticity, creating an acidic and immunosuppressive tumor microenvironment, and inducing noncancerous cells to become tumor-promoting. In addition, pancreatic cancer has often metastasized to local and distant sites by the time of diagnosis, suggesting that a similar mechanism is operating from the precancerous stage. Here, we review key recent findings on how pancreatic cancers acquire plasticity, undergo metabolic reprogramming, and promote immunosuppressive microenvironment formation during their evolution. Furthermore, we present the following two signaling pathways that we have identified: one based on the small G-protein ARF6 driven by KRAS/TP53 mutations, and the other based on the RNA-binding protein Arid5a mediated by inflammatory cytokines, which promote both metabolic reprogramming and immune evasion in pancreatic cancer. Finally, the striking diversity among pancreatic cancers in the relative importance of mutational burden and the tumor microenvironment, their clinical relevance, and the potential for novel therapeutic strategies will be discussed.

Triclocarban disrupts the activation and differentiation of human CD8+ T cells by suppressing the vitamin D receptor signaling

Triclocarban (TCC) is a widely applied environmental endocrine-disrupting chemical (EDC). Similar to most of EDCs, TCC potentially damages the immunity of various species. However, whether and how TCC impacts the adaptive immunity in mammals has yet to be determined. Herein, we discovered that TCC disrupts the activation and differentiation of CD8+ T cells in primary human peripheral blood samples, purified CD8+ T cells, and in mice in vivo. Mechanistically, TCC might block the activation of the vitamin D receptor (VDR) and reduce the synthesis of cholesterol, a precursor of vitamin D, resulting in inhibition of VDR signaling due to the suppression of both its ligand and the receptor itself by TCC. Our findings elucidate the hazard and potential mechanisms of TCC in mammalian adaptive immunity and highlighted VDR as a potential therapeutic target for the immunodeficiency caused by TCC.

Local administration of immunotherapy for patients with skin cancer: A systematic review

Since the introduction of immune checkpoint inhibitors (ICIs) targeting PD-1 and CTLA-4 receptors, survival has improved significantly for patients with irresectable and metastatic skin cancer, including cutaneous squamous cell cancer and melanoma. However, systemic administration of these drugs is associated with immune related adverse events (irAEs), which can be severe, irreversible and even fatal. To reduce the risk of irAEs associated with systemic exposure to immunotherapeutic drugs, local administration of low doses could be considered. This systematic review provides an overview of early phase clinical trials with drugs that are currently under investigation for intratumoral administration in patients with melanoma and non-melanoma skin cancer.

The standardization and efficacy of fermented Crescentia cujete (L.) in combination with enrofloxacin against artificially induced pneumonic pasteurellosis in rat models

Background

Pasteurella multocida is an opportunistic bacterium that causes pneumonic pasteurellosis (PP). The common treatment against PP is using antibiotics in conjunction with nonsteroidal anti-inflammatory drugs (NSAIDs). This combination presents various complications, i.e., immune-depression. Hence, the alternative therapy to replace the effects of NSAIDs needs to be clarified. One of them is using fermented calabash [Crescentia cujete (L.)] (FCC).

Aim

This study aimed to elucidate the efficacy of FCC in combination with enrofloxacin against artificially induced PP in rat models.

Methods

The calabash was collected and fermented. Moreover, the product of FCC was standardized regarding its biochemical compounds using Liquid chromatography-tandem mass spectrometry and high-performance liquid chromatography. This study used 30 male Sprague Dawley rats, weighing 251.52 ± 2.65 grams, 6 months old. The rats were divided into six groups as follows: G1 (control); G2 (infected with Pasteurella multocida + untreated); G3 (infected + 20 mg/kg enrofloxacin); G4 (infected + 20 mg/kg enrofloxacin + 30 mg/kg ibuprofen); G5 (infected + 20 mg/kg enrofloxacin + 2.96 mg/kg FCC); and G6 (infected + 20 mg/kg enrofloxacin + 5.92 mg/kg FCC). The treatment was given once daily for 7 days. On day eight, the rats were radiographed. The serum was collected and tested against C-reactive protein (CRP) and procalcitonin. The rats were euthanized and lung tissue was collected for histopathology and immunohistochemistry against CD4+, CD8+, and COX-2. The data were analyzed using SPSS.

Results

This study indicated that FCC contains choline, phytonadione, alpha-tocopherol, and retinol. Moreover, using FCC as a combination therapy with enrofloxacin against PP in group G6 promotes a repair of radiology image compared to other treatments (p < 0.05). Group G5 and G6 showed increased activity of bronchial-associated lymphoid tissue, immune expression of CD4+ and COX-2, and the level of CRP and procalcitonin within the lung tissue (p < 0.05). Group G6 indicated better effects in various parameters in this study. However, the FCC has not influenced the immune expression of CD8+ during PP (p > 0.05).

Conclusion

This study proved that FCC could be used in rat models as an alternative anti-inflammatory treatment in combination with enrofloxacin against PP. Further research is needed to explore other effects of FCC to support the current findings.

B2M or CIITA knockdown decreased the alloimmune response of dental pulp stem cells: an in vitro study

BACKGROUND

Dental pulp stem cells (DPSCs) have acquired noteworthy attention for their application in treating ischemic diseases and facilitating tissue regeneration. However, the host's immune response following allogenic DPSC transplantation often handicaps the long-term survival of transplanted cells, thereby limiting the application of DPSCs in cell therapy. This study aims to investigate whether genetic modification can alleviate the immunogenicity of DPSCs.

METHODS

Beta 2-microglobulin (B2M) and the class II histocompatibility complex transactivator (CIITA) were individually knocked down in DPSCs by lentiviral particles encoding short hairpin (sh) RNAs. The self-renewal capacity and pluripotency of DPSCs-shB2M (B2M silenced DPSCs) and DPSCs-shCIITA (CIITA silenced DPSCs) were evaluated by CCK8 and differentiation assays including osteogenesis, adipogenesis, and neurogenesis. The expression of HLA-I and HLA-II in DPSCs-shB2M and DPSCs-shCIITA after IFN-γ treatment were analyzed by western blotting, immunofluorescence, and flow cytometry. The function of genetically modified cells was assessed by leukocyte-mediated cytotoxicity and T-cell proliferation assays.

RESULTS

Western blotting, immunofluorescence, and flow cytometry revealed that DPSCs-shB2M and DPSCs-shCIITA exhibited impaired IFN-γ inducible HLA-I and HLA-II expression. There were no significant differences in the self-renewal capacity and pluripotency among DPSCs-shB2M, DPSCs-shCIITA, and control groups (p > 0.05). Lower leukocyte-mediated cytotoxicity and higher cell survival rates were found in DPSCs-shB2M and DPSCs-shCIITA groups compared to the control (p < 0.05). T cell proliferation was significantly inhibited in both DPSCs-shB2M and DPSCs-shCIITA groups (p < 0.05).

CONCLUSION

Genetic knockdown of B2M or CIITA in DPSCs substantially reduced their immunogenicity without compromising their stemness, thereby broadening the clinical application of DPSCs in cell therapy and tissue regeneration.

MDM2 inhibitors in cancer immunotherapy: Current status and perspective

Murine double minute 2 (MDM2) plays an essential role in the cell cycle, apoptosis, DNA repair, and oncogene activation through p53-dependent and p53-independent signaling pathways. Several preclinical studies have shown that MDM2 is involved in tumor immune evasion. Therefore, MDM2-based regulation of tumor cell-intrinsic immunoregulation and the immune microenvironment has attracted increasing research attention. In recent years, immune checkpoint inhibitors targeting PD-1/PD-L1 have been widely used in the clinic. However, the effectiveness of a single agent is only approximately 20%-40%, which may be related to primary and secondary drug resistance caused by the dysregulation of oncoproteins. Here, we reviewed the role of MDM2 in regulating the immune microenvironment, tumor immune evasion, and hyperprogression during immunotherapy. In addition, we summarized preclinical and clinical findings on the use of MDM2 inhibitors in combination with immunotherapy in tumors with MDM2 overexpression or amplification. The results reveal that the inhibition of MDM2 could be a promising strategy for enhancing immunotherapy.

CD8+ tissue-resident memory T cells are essential in bleomycin-induced pulmonary fibrosis

Human tissue-resident memory T (TRM) cells play a crucial role in protecting the body from infections and cancers. Recent research observed increased numbers of TRM cells in the lung tissues of idiopathic pulmonary fibrosis patients. However, the functional consequences of TRM cells in pulmonary fibrosis remain unclear. Here, we found that the numbers of TRM cells, especially the CD8+ subset, were increased in the mouse lung with bleomycin-induced pulmonary fibrosis. Increasing or decreasing CD8+ TRM cells in mouse lungs accordingly altered the severity of fibrosis. In addition, the adoptive transfer of CD8+ T cells containing a large number of CD8+ TRM cells from fibrotic lungs was sufficient to induce pulmonary fibrosis in control mice. Treatment with chemokine CC-motif ligand (CCL18) induced CD8+ TRM cell expansion and exacerbated fibrosis, whereas blocking C-C chemokine receptor 8 (CCR8) prevented CD8+ TRM recruitment and inhibited pulmonary fibrosis. In conclusion, CD8+ TRM cells are essential for bleomycin-induced pulmonary fibrosis, and targeting CCL18/CCR8/CD8+ TRM cells may be a potential therapeutic approach. NEW & NOTEWORTHY The role of CD8+ TRM cells in the development of pulmonary fibrosis was validated and studied in the classic model of pulmonary fibrosis. It was proposed for the first time that CCL18 has a chemotactic effect on CD8+ TRM cells, thereby exacerbating pulmonary fibrosis.

Abnormal Cellular Populations Shape Thymic Epithelial Tumor Heterogeneity and Anti-Tumor by Blocking Metabolic Interactions in Organoids

A variety of abnormal epithelial cells and immature and mature immune cells in thymic epithelial tumors (TETs) affect histopathological features, the degree of malignancy, and the response to treatment. Here, gene expression, trajectory inference, and T cell antigen receptor (TCR)-based lineage tracking are profiled in TETs at single-cell resolution. An original subpopulation of KRT14+ progenitor cells with a spindle cell phenotype is shown. An abnormal infiltration of immature T cells with a TCR hyper-rearrangement state is revealed, due to the lack of CCL21+ medullary epithelial cells. For thymic carcinoma, the novel biomarkers of MSLN, CCL20, and SLC1A5 are identified and observed an elevated expression of LAG3 and HAVCR2 in malignant tumorn-infiltrating mature T cells. These common features based on the single-cell populations may inform pathological reclassification of TETs. Meanwhile, it is found that macrophages (MACs) attract thymic tumor cells through the LGALS9-SLC1A5 axis, providing them with glutamine to elicit metabolic reprogramming. This MAC-based metabolic pattern can promote malignancy progression. Additionally, an interactive immune environment in TETs is identified that correlates with the infiltration of abnormal FOXI1+ CFTR- ionocytes. Collectively, the data broaden the knowledge of TET cellular ecosystems, providing a basis for tackling histopathological diagnosis and related treatment.

Tissue-resident memory T cells: Harnessing their properties against infection for cancer treatment

We have rapidly gained insights into the presence and function of T lymphocytes in non-lymphoid tissues, the tissue-resident memory T (TRM) cells. The central pillar of adaptive immunity has been expanded from classic central memory T cells giving rise to progeny upon reinfection and effector memory cells circulating through the blood and patrolling the tissues to include TRM cells that reside and migrate inside solid organs and tissues. Their development and maintenance have been studied in detail, providing exciting clues on how their unique properties used to fight infections may benefit therapies against solid tumors. We provide an overview of CD8 TRM cells and the properties that make them of interest for vaccination and cancer therapies.

Neoantigen sequestrated autophagosomes as therapeutic cancer vaccines

Neoantigens serve as ideal personalized cancer vaccines because of their high immunogenicity, ability to evade central thymic tolerance, and minimal risk of eliciting autoimmune responses. Herein, we describe a genetically engineered autophagosome-based neoantigen vaccine (APNV) in combination with an immune checkpoint inhibitor (anti-PD-1 antibody) for cancer immunotherapy. The APNV was derived from engineered NIH 3T3 cells, which co-express melanoma neoantigens and autophagosome maker microtubule-associated proteins 1 A/1B light chain 3B (LC3), from which the LC3-labeled neoantigen-autophagosomes were isolated. These purified autophagosomes, in conjunction with vaccine adjuvants high-mobility group box 1 (HMGB1) and granulocyte-macrophage colony-stimulating factor (GM-CSF), were integrated into a hydrogel to create an APNV. The APNV effectively activated dendritic cells both in vitro and in vivo. Moreover, APNV, in combination with checkpoint blockade therapy, significantly hampered post-surgical tumor recurrence in a subcutaneous melanoma tumor model and effectively impeded metastatic progression in a melanoma lung metastasis model. This APNV may be conducive to making personalized therapeutic neoantigen vaccines for cancer immunotherapy.

In vivo safety evaluation and tracing of arginylglycylaspartic acid-engineered phage nanofiber in murine model

The engineered phage YSY184, mimicking the extracellular matrix nanofiber, effectively promotes stem cell differentiation and angiogenesis. This study evaluated its safety in a mouse model, monitoring weight, immunogenicity, spleen immune responses, and macrophage infiltration. Rapid clearance of YSY184 was observed, with peak tissue presence within three hours, significantly reduced by 24 hours, and negligible after one month. No adverse physiological or pathological effects were detected post-administration, affirming YSY184's safety and underscore its potential for therapeutic use, warranting further clinical exploration.

A single-dose circular RNA vaccine prevents Zika virus infection without enhancing dengue severity in mice

Antibody-dependent enhancement (ADE) is a potential concern for the development of Zika virus (ZIKV) vaccines. Cross-reactive but poorly neutralizing antibodies, usually targeting viral pre-membrane or envelope (E) proteins, can potentially enhance dengue virus (DENV) infection. Although E domain III (EDIII) contains ZIKV-specific epitopes, its immunogenicity is poor. Here, we show that dimeric EDIII, fused to human IgG1 Fc fragment (EDIII-Fc) and encoded by circular RNA (circRNA), induces better germinal center reactions and higher neutralizing antibodies compared to circRNAs encoding monomeric or trimeric EDIII. Two doses of circRNAs encoding EDIII-Fc and ZIKV nonstructural protein NS1, another protective antigen, prevent lethal ZIKV infection in neonates born to immunized C57BL/6 mice and in interferon-α/β receptor knockout adult C57BL/6 mice. Importantly, a single-dose optimized circRNA vaccine with improved antigen expression confers potent and durable protection without inducing obvious DENV ADE in mice, laying the groundwork for developing flavivirus vaccines based on circRNAs encoding EDIII-Fc and NS1.

Potential Contributions of Human Endogenous Retroviruses in Innate Immune Memory

The phenomenon wherein innate immune cells adopt long-term inflammatory phenotypes following the first stimuli is named trained immunity and can improve host defense against infections. Transcriptional and epigenetic reprogramming are critical mechanisms of trained immunity; however, the regulatory networks are not entirely clear at present. The human endogenous retroviruses (HERVs) provide large amounts of transcriptional regulators in the regulatory pathways. In this study, we analyzed published large omics data to explore the roles of such "dark matter" of the human genome in trained and tolerant macrophages. We collected 80 RNA sequencing data and 62 sequencing data to detect histone modifications and active regulatory regions from nine published studies on trained and tolerant macrophages. By analyzing the characteristics of transcription and epigenetic modification of HERVs, as well as their association with gene expression, we found that 15.3% of HERVs were transcribed nonrandomly from noncoding regions and enriched in specific HERV families and specific chromosomes, such as chromosomes 11, 15, 17, and 19, and they were highly related with the expression of adjacent genes. We found that 295 differentially expressed HERVs are located in 50-kbp flanking regions of 142 differentially expressed genes. We found epigenetic changes of these HERVs and that overlap with predicted enhancers and identified 35 enhancer-like HERVs. The related genes were highly involved in the activation and inflammatory responses, such as the TLR pathway. Other pathways including phosphoinositide signaling and transport of folate and K+ might be also related with trained immunity, which require further study. These results demonstrated that HERVs might play important roles in trained immunity.

Active role of the immune system in metabolic dysfunction-associated steatotic liver disease

Non-alcoholic fatty liver disease, recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is a complex multifactorial disease that progresses from steatohepatitis (MASH) to liver cirrhosis and liver cancer. Recent research has revealed that crosstalk between innate immune cells and hepatic parenchymal and non-parenchymal cells is involved in the pathogenesis of liver disease in MASLD/MASH. Of particular importance, novel inflammatory mechanisms, including macrophage diversity, neutrophil NETosis, B-cell biology, auto-reactive T cells, unconventional T cells, and dendritic cell-T cell interactions, are considered key drivers for disease progression. These mechanisms and factors are potential targets for the therapeutic intervention of MASLD/MASH. In this review, we focus on recent discoveries related to liver inflammation and discuss the role of innate immune cell subsets in MASLD/MASH.

NitraTh epitope-based neoantigen vaccines for effective tumor immunotherapy

Neoantigen vaccines represent an emerging and promising strategy in the field of tumor immunotherapy. Despite their potential, designing an effective neoantigen vaccine remains a challenge due to the current limitations in predicting CD4+ T cell epitopes with high accuracy. Here, we introduce a novel approach to neoantigen vaccine design that does not rely on computational prediction of CD4+ T cell epitopes. Utilizing nitrated helper T cell epitope containing p-nitrophenylalanine, termed "NitraTh epitope," we have successfully engineered a series of tumor neoantigen vaccines capable of eliciting robust neoantigen-specific immune responses. With the help of NitraTh epitope, even mutations with low predicted affinity for MHC class I molecules were successfully induced to elicit neoantigen-specific responses. In H22 cell allograft and patient-derived xenograft (PDX) liver cancer mouse models, the NitraTh epitope-based neoantigen vaccines significantly suppressed tumor progression. More strikingly, through single-cell sequencing we found that the NitraTh epitope-based neoantigen vaccines regulate macrophage reprogramming and modulate macrophages to decrease the levels of the immunosuppressive molecule prostaglandin E2 (PGE2), which in turn reshapes the tumor immunosuppressive microenvironment. In summary, NitraTh epitope-based neoantigen vaccines possess the dual effects of potently activating neoantigen-specific immunity and alleviating immunosuppression, potentially providing a new paradigm for the design of tumor neoantigen vaccines.

Benefit delayed immunosenescence by regulating CD4+T cells: A promising therapeutic target for aging-related diseases

CD4+T cells play a notable role in immune protection at different stages of life. During aging, the interaction between the body's internal and external environment and CD4+T cells results in a series of changes in the CD4+T cells pool making it involved in immunosenescence. Many studies have extensively examined the subsets and functionality of CD4+T cells within the immune system, highlighted their pivotal role in disease pathogenesis, progression, and therapeutic interventions. However, the underlying mechanism of CD4+T cells senescence and its intricate association with diseases remains to be elucidated and comprehensively understood. By summarizing the immunosenescent progress and network of CD4+T cell subsets, we reveal the crucial role of CD4+T cells in the occurrence and development of age-related diseases. Furthermore, we provide new insights and theoretical foundations for diseases targeting CD4+T cell subsets aging as a treatment focus, offering novel approaches for therapy, especially in infections, cancers, autoimmune diseases, and other diseases in the elderly.

Superior antitumor immune response achieved with proton over photon immunoradiotherapy is amplified by the nanoradioenhancer NBTXR3

Recent findings suggest that immunoradiotherapy (IRT), combining photon radiotherapy (XRT) or proton radiotherapy (PRT) with immune checkpoint blockade, can enhance systemic tumor control. However, the comparative efficacy of XRT and PRT in IRT remains understudied. To address this, we compared outcomes between XRT + αPD1 and PRT + αPD1 in murine αPD1-resistant lung cancer (344SQR). We also assessed the impact of the nanoparticle radioenhancer NBTXR3 on both XRT + αPD1 and PRT + αPD1 for tumor control and examined the tumor immune microenvironment using single-cell RNA sequencing (scRNAseq). Additionally, mice cured by NBTXR3 + PRT + αPD1 were rechallenged with three lung cancer cell lines to evaluate memory antitumor immunity. PRT + αPD1 showed superior local tumor control and abscopal effects compared to XRT + αPD1. NBTXR3 + PRT + αPD1 significantly outperformed NBTXR3 + XRT + αPD1 in tumor control, promoting greater infiltration of antitumor lymphocytes into irradiated tumors. Unirradiated tumors treated with NBTXR3 + PRT + αPD1 had more NKT cells, CD4 T cells, and B cells, with fewer Tregs, than those treated with NBTXR3 + XRT + αPD1. NBTXR3 + PRT + αPD1 also stimulated higher expression of IFN-γ, GzmB, and Nkg7 in lymphocytes, reduced the TGF-β pathway, and increased tumor necrosis factor alpha expression compared to NBTXR3 + XRT + αPD1. Moreover, NBTXR3 + PRT + αPD1 resulted in greater M1 macrophage polarization in both irradiated and unirradiated tumors. Mice achieving remission through NBTXR3 + PRT + αPD1 exhibited a robust memory immune response, effectively inhibiting growth of subsequent tumors from three distinct lung cancer cell lines. Proton IRT combined with NBTXR3 offers enhanced tumor control and survival rates over photon-based treatments in managing αPD1-resistant lung cancer, indicating its potential as a potent systemic therapy.

CD4+ T cell help during early acute hepacivirus infection is critical for viral clearance and the generation of a liver-homing CD103+CD49a+ effector CD8+ T cell subset

In hepatitis C virus (HCV) infection, CD4+ and CD8+ T cells are crucial for viral control. However, a detailed understanding of the kinetic of CD4+ T cell help and its role in the generation of different CD8+ T cell subsets during acute infection is lacking. The absence of a small HCV animal model has impeded mechanistic studies of hepatic antiviral T cell immunity and HCV vaccine development. In this study, we used a recently developed HCV-related rodent hepacivirus infection mouse model to investigate the impact of CD4+ T cell help on the hepatic CD8+ T cell response and viral clearance during hepacivirus infection in vivo. Our results revealed a specific kinetic of CD4+ T cell dependency during acute infection. Early CD4+ T cell help was essential for CD8+ T cell priming and viral clearance, while CD4+ T cells became dispensable during later stages of acute infection. Effector CD8+ T cells directly mediated timely hepacivirus clearance. An analysis of hepatic CD8+ T cells specific for two different viral epitopes revealed the induction of subsets of liver-homing CD103+CD49a+ and CD103-CD49a+ effector CD8+ T cells with elevated IFN-γ and TNF-α production. CD103+CD49a+ T cells further persisted as tissue-resident memory subsets. A lack of CD4+ T cell help and CD40L-CD40 interactions resulted in reduced effector functions and phenotypical changes in effector CD8+ T cells and a specific loss of the CD103+CD49a+ subset. In summary, our study shows that early CD4+ T cell help through CD40L signaling is essential for priming functional effector CD8+ T cell subsets, including unique liver-homing subsets, and hepacivirus clearance.

Opportunities and challenges for T cell-based influenza vaccines

Vaccination remains our main defence against influenza, which causes substantial annual mortality and poses a serious pandemic threat. Influenza virus evades immunity by rapidly changing its surface antigens but, even when the vaccine is well matched to the current circulating virus strains, influenza vaccines are not as effective as many other vaccines. Influenza vaccine development has traditionally focused on the induction of protective antibodies, but there is mounting evidence that T cell responses are also protective against influenza. Thus, future vaccines designed to promote both broad T cell effector functions and antibodies may provide enhanced protection. As we discuss, such vaccines present several challenges that require new strategic and economic considerations. Vaccine-induced T cells relevant to protection may reside in the lungs or lymphoid tissues, requiring more invasive assays to assess the immunogenicity of vaccine candidates. T cell functions may contain and resolve infection rather than completely prevent infection and early illness, requiring vaccine effectiveness to be assessed based on the prevention of severe disease and death rather than symptomatic infection. It can be complex and costly to measure T cell responses and infrequent clinical outcomes, and thus innovations in clinical trial design are needed for economic reasons. Nevertheless, the goal of more effective influenza vaccines justifies renewed and intensive efforts.

Indirect suppression of CD4 T cell activation through LAG-3-mediated trans-endocytosis of MHC class II

Blockade of immune checkpoint receptors has shown outstanding efficacy for tumor immunotherapy. Promising treatment with anti-lymphocyte-activation gene-3 (LAG-3) has already been recognized as the next efficacious treatment, but there is still limited understanding of the mechanism of LAG-3-mediated immune suppression. Here, utilizing high-resolution molecular imaging, we find a mechanism of CD4 T cell suppression via LAG-3, in which LAG-3-bound major histocompatibility complex (MHC) class II molecules on antigen-presenting cells (APCs) gather at the central region of an immunological synapse and are trans-endocytosed by T cell receptor-driven internalization motility toward CD4 and CD8 T cells expressing LAG-3. Downregulation of MHC class II molecules on APCs thus results in the attenuation of their antigen-presentation function and impairment of CD4 T cell activation. From these data, anti-LAG-3 treatment is suggested to have potency to directly block the inhibitory signaling via LAG-3 and simultaneously reduce MHC class II expression on APCs by LAG-3-mediated trans-endocytosis for recovery from T cell exhaustion.

A promising strategy to improve the stability and immunogenicity of killed but metabolically active vaccines: low-temperature preparation and coating of nanoparticles

Bacteria are becoming an increasingly serious threat to human health. The emergence of super bacteria makes clinical treatment more difficult. Vaccines are one of the most effective means of preventing and treating bacterial infections. As a new class of vaccines, killed but metabolically active (KBMA) vaccines provide the immunogenicity of live vaccines and the safety of inactivated vaccines. Herein, a promising strategy is proposed to improve the stability and immunogenicity of KBMA vaccines. KBMA vaccines were produced at low temperature (4 °C), and the bacterial surface was engineered using mesoporous silica nanoparticle (MSN) coating. Compared to vaccines prepared at room temperature, the metabolic activity of KBMA vaccines prepared at 4 °C remarkably improved. Benefiting from the induction of MSNs, the stability of KBMA vaccines was increased and the preservation time was prolonged at 4 °C. Meanwhile, metabolomics analysis showed that the metabolite spectrum of live bacteria changed after photochemical treatment and MSN coating, which interfered with organic acid metabolism pathways, lipid metabolism and biosynthesis of secondary metabolites. Furthermore, the immune response in the mice treated with KBMA/MSN vaccines was similar to that in those treated with live vaccines and stronger than that in those treated with inactivated vaccines. In comparison with the control group, bacteria tissue burdens of KBMA/MSN group were significantly reduced. CD4+ T cells dominated immune responses for the protection of mice. Thus, the current work promotes the application of KBMA vaccines, providing an alternative choice for treating bacterial infections.

Novel tumor gene expression signatures improve the overall survival prediction efficiency over tumor mutation burden and PD-L1 expression in bladder carcinoma with checkpoint blockade immunotherapy

Although immune checkpoint blockade therapy (ICBT) has revolutionized cancer treatment with good therapeutic response in a number of human cancers, including bladder cancer, many cancers still do not respond to ICBT. Analyzing genetic signatures helps the understanding of underlying biological mechanisms. Here, based on two cohorts of bladder cancer patients receiving ICBT, we identified three novel ICBT-associated signatures in the bladder cancer microenvironment, involving genomic stability, angiogenesis and RNA regulatory, which affect PD-L1 expression and patient response to ICBT. The combinations of these signatures with TMB or PD-L1 expression improved the overall survival prediction efficiency over TMB and PD-L1 expression alone for patients receiving ICBT. Moreover, we utilized two methods to search potential drugs or small-molecules that have an impact on ICBT-associated signatures. This study provides new molecular insight into ICBT response of bladder cancer and has the potential to improve the prediction accuracy for patients to benefit from ICBT.

T-cell responses to ancestral SARS-CoV-2 and Omicron variant among unvaccinated pregnant and postpartum women living with and without HIV in South Africa

SARS-CoV-2 cell-mediated immunity remains understudied during pregnancy in unvaccinated Black African women living with HIV (WLWH) from low- and middle-income countries. We investigated SARS-CoV-2-specific T-cell responses 1 month following infection in 24 HIV-uninfected women and 15 WLWH at any stage during pregnancy or postpartum. The full-length spike (FLS) glycoprotein and nucleocapsid (N) protein of wild-type (WT) SARS-CoV-2, as well as mutated spike protein regions found in the Omicron variant (B.1.1.529) were targeted by flow cytometry. WT-specific CD4+ and CD8+ T cells elicited similar FLS- and N-specific responses in HIV-uninfected women and WLWH. SARS-CoV-2-specific T-lymphocytes were predominantly TNF-α monofunctional in pregnant and postpartum women living with and without HIV, with fever cells producing either IFN-γ or IL-2. Furthermore, T-cell responses were unaffected by Omicron-specific spike mutations as similar responses between Omicron and the ancestral virus were detected for CD4+ and CD8+ T cells. Our results collectively demonstrate comparable T-cell responses between WLWH on antiretroviral therapy and HIV-uninfected pregnant and postpartum women who were naïve to Covid-19 vaccination. Additionally, we show that T cells from women infected with the ancestral virus, Beta variant (B.1.351), or Delta variant (B.1.617.2) can cross-recognize Omicron, suggesting an overall preservation of T-cell immunity.

Ovarian cancer ascites proteomic profile reflects metabolic changes during disease progression

Ovarian cancer (OC) patients develop ascites, an accumulation of ascitic fluid in the peritoneal cavity anda sign of tumour dissemination within the peritoneal cavity. This body fluid is under-researched, mainly regarding the ascites formed during tumour progression that have no diagnostic value and, therefore, are discarded. We performed a discovery proteomics study to identify new biomarkers in the ascites supernatant of OC patients. In this preliminary study, we analyzed a small amount of OC ascites to highlight the importance of not discarding such biological material during treatment, which could be valuable for OC management. Our findings reveal that OC malignant ascitic fluid (MAF) displays a proliferative environment that promotes the growth of OC cells that shift the metabolic pathway using alternative sources of nutrients, such as the cholesterol pathway. Also, OC ascites drained from patients during treatment showed an immunosuppressive environment, with up-regulation of proteins from the signaling pathways of IL-4 and IL-13 and down-regulation from the MHC-II. This preliminary study pinpointed a new protein (Transmembrane Protein 132A) in the OC context that deserves to be better explored in a more extensive cohort of patients' samples. The proteomic profile of MAF from OC patients provides a unique insight into the metabolic kinetics of cancer cells during disease progression, and this information can be used to develop more effective treatment strategies.

Reprogramming the immunosuppressive tumor microenvironment through nanomedicine: an immunometabolism perspective

Increasing evidence indicates that immunotherapy is hindered by a hostile tumor microenvironment (TME) featured with deprivation of critical nutrients and pooling of immunosuppressive metabolites. Tumor cells and immunosuppressive cells outcompete immune effector cells for essential nutrients. Meanwhile, a wide range of tumor cell-derived toxic metabolites exerts negative impacts on anti-tumor immune response, diminishing the efficacy of immunotherapy. Nanomedicine with excellent targetability offers a novel approach to improving cancer immunotherapy via metabolically reprogramming the immunosuppressive TME. Herein, we review recent strategies of enhancing immunotherapeutic effects through rewiring tumor metabolism via nanomedicine. Attention is drawn on immunometabolic tactics for immune cells and stromal cells in the TME via nanomedicine. Additionally, we discuss future directions of developing metabolism-regulating nanomedicine for precise and efficacious cancer immunotherapy.

A review of CD4+ T cell differentiation and diversity in dogs

CD4+ T cells are an integral component of the adaptive immune response, carrying out many functions to combat a diverse range of pathogenic challenges. These cells exhibit remarkable plasticity, differentiating into specialized subsets such as T helper type 1 (TH1), TH2, TH9, TH17, TH22, regulatory T cells (Tregs), and follicular T helper (TFH) cells. Each subset is capable of addressing a distinct immunological need ranging from pathogen eradication to regulation of immune homeostasis. As the immune response subsides, CD4+ T cells rest down into long-lived memory phenotypes-including central memory (TCM), effector memory (TEM), resident memory (TRM), and terminally differentiated effector memory cells (TEMRA) that are localized to facilitate a swift and potent response upon antigen re-encounter. This capacity for long-term immunological memory and rapid reactivation upon secondary exposure highlights the role CD4+ T cells play in sustaining both adaptive defense mechanisms and maintenance. Decades of mouse, human, and to a lesser extent, pig T cell research has provided the framework for understanding the role of CD4+ T cells in immune responses, but these model systems do not always mimic each other. Although our understanding of pig immunology is not as extensive as mouse or human research, we have gained valuable insight by studying this model. More akin to pigs, our understanding of CD4+ T cells in dogs is much less complete. This disparity exists in part because canine immunologists depend on paradigms from mouse and human studies to characterize CD4+ T cells in dogs, with a fraction of available lineage-defining antibody markers. Despite this, every major CD4+ T cell subset has been described to some extent in dogs. These subsets have been studied in various contexts, including in vitro stimulation, homeostatic conditions, and across a range of disease states. Canine CD4+ T cells have been categorized according to lineage-defining characteristics, trafficking patterns, and what cytokines they produce upon stimulation. This review addresses our current understanding of canine CD4+ T cells from a comparative perspective by highlighting both the similarities and differences from mouse, human, and pig CD4+ T cell biology. We also discuss knowledge gaps in our current understanding of CD4+ T cells in dogs that could provide direction for future studies in the field.

Effect of dietary inclusion of 25-hydroxyvitamin D₃ and vitamin E on performance, gut health, oxidative status, and immune response in laying hens infected with coccidiosis

Vitamin D3 (25-hydroxyvitamin D3 (VD)) and vitamin E (VE) have proven to have immunomodulatory and antioxidant functions along with capacities to improve the reproductive function in chickens. Coccidiosis in laying hens at different stages of growth has been shown to negatively affect performance, immune response, and oxidative status, thus increasing the cost of production. A study was conducted to evaluate the influence of dietary VD or VE on performance, gut health, immune response, and oxidative status of laying hens at peak production. Laying hens (23 wk-of-age, n = 225) were randomly allocated into 5 treatment groups (n = 9 hens/replicate) with 5 replicate groups each: 1) unchallenged control (UC), 2) pair-fed control (PF), 3) challenged control (CC), 4) challenged control top-dressed with 5,000 IU of 25-hydroxyvitamin D3 (VD) per kg of diet, and 5) challenged control top-dressed with 100 IU of DL-α-tocopherol (VE). At 25 wk-of-age, hens grouped in CC, VD, and VE were challenged with mixed Eimeria spp. to induce coccidiosis. VD or VE supplemented hens did not impact bird body weight; however, egg production increased by 10.36% and 13.77%, respectively (P < 0.0001). Furthermore, the gut health of the hens was improved with either VD or VE supplementation, as indicated by lowered gut permeability and intestinal lesion scores (P < 0.05). VE significantly reduced the heterophil count (P = 0.0490) alongside numerically increasing the peripheral CD4+ and CD8+ T cells and monocyte counts (P > 0.05). Both VD or VE increased the TAC at 14 DPI compared to UC (P<0.05). Preliminary findings suggest that dietary VD or VE supplementation has the potential to improve gut health, modulate the immune response, and increase egg production in coccidiosis-infected laying hens.

Maternal Undernutrition Affects Fetal Thymus DNA Methylation, Gene Expression, and, Thereby, Metabolism and Immunopoiesis in Wagyu (Japanese Black) Cattle

We aimed to determine the effects of maternal nutrient restriction (MNR) on the DNA methylation and gene expression patterns associated with metabolism and immunopoiesis in the thymuses of fetal Wagyu cattle. Pregnant cows were allocated to two groups: a low-nutrition (LN; 60% nutritional requirement; n = 5) and a high-nutrition (HN; 120% nutritional requirement, n = 6) group, until 8.5 months of gestation. Whole-genome bisulfite sequencing (WGBS) and RNA sequencing were used to analyze DNA methylation and gene expression, while capillary electrophoresis-Fourier transform mass spectrometry assessed the metabolome. WGBS identified 4566 hypomethylated and 4303 hypermethylated genes in the LN group, with the intergenic regions most frequently being methylated. Pathway analysis linked hypoDMGs to Ras signaling, while hyperDMGs were associated with Hippo signaling. RNA sequencing found 94 differentially expressed genes (66 upregulated, 28 downregulated) in the LN group. The upregulated genes were tied to metabolic pathways and oxidative phosphorylation; the downregulated genes were linked to natural killer cell cytotoxicity. Key overlapping genes (GRIA1, CACNA1D, SCL25A4) were involved in cAMP signaling. The metabolomic analysis indicated an altered amino acid metabolism in the MNR fetuses. These findings suggest that MNR affects DNA methylation, gene expression, and the amino acid metabolism, impacting immune system regulation during fetal thymus development in Wagyu cattle.

Unveiling the unique role of TSPAN7 across tumors: a pan-cancer study incorporating retrospective clinical research and bioinformatic analysis

BACKGROUND

TSPAN7 is an important factor in tumor progression. However, the precise function of TSPAN7 and its role in pan-cancer are not clear.

METHODS

Based on Xinhua cohort incorporating 370 patients with kidney neoplasm, we conducted differential expression analysis by immunohistochemistry between tumor and normal tissues, and explored correlations of TSPAN7 with patients' survival. Subsequently, we conducted a pan-cancer study, and successively employed differential expression analysis, competing endogenous RNA (ceRNA) analysis, protein-protein interaction (PPI) analysis, correlation analysis of TSPAN7 with clinical characteristics, tumor purity, tumor genomics, tumor immunity, and drug sensitivity. Last but not least, gene set enrichment analysis was applied to identify enriched pathways of TSPAN7.

RESULTS

In Xinhua cohort, TSPAN7 expression was significantly up-regulated (P-value = 0.0019) in tumor tissues of kidney neoplasm patients. High TSPAN7 expression was associated with decreases in overall survival (OS) (P-value = 0.009) and progression-free survival (P-value = 0.009), and it was further revealed as an independent risk factor for OS (P-value = 0.0326, HR = 5.66, 95%CI = 1.155-27.8). In pan-cancer analysis, TSPAN7 expression was down-regulated in most tumors, and it was associated with patients' survival, tumor purity, tumor genomics, tumor immunity, and drug sensitivity. The ceRNA network and PPI network of TSPAN7 were also constructed. Last but not least, the top five enriched pathways of TSPAN7 in various tumors were identified.

CONCLUSION

TSPAN7 served as a promising biomarker of various tumors, especially kidney neoplasms, and it was closely associated with tumor purity, tumor genomics, tumor immunology, and drug sensitivity in pan-cancer level.

Unveiling major histocompatibility complex-mediated pan-cancer immune features by integrated single-cell and bulk RNA sequencing

Immune checkpoint inhibitors (ICIs) have transformed cancer therapy, yet persistent challenges such as low response rate and significant heterogeneity necessitate attention. The pivotal role of the major histocompatibility complex (MHC) in ICI efficacy, its intricate impacts and potentials as a prognostic marker, warrants comprehensive exploration. This study integrates single-cell RNA sequencing (scRNA-seq), bulk RNA-seq, and spatial transcriptomic analyses to unveil pan-cancer immune characteristics governed by the MHC transcriptional feature (MHC.sig). Developed through scRNA-seq analysis of 663,760 cells across diverse cohorts and validated in 30 solid cancer types, the MHC.sig demonstrates a robust correlation between immune-related genes and infiltrating immune cells, highlighting its potential as a universal pan-cancer marker for anti-tumor immunity. Screening the MHC.sig for therapeutic targets using CRISPR data identifies potential genes for immune therapy synergy and validates its predictive efficacy for ICIs responsiveness across diverse datasets and cancer types. Finally, analysis of cellular communication patterns reveals interactions between C1QC+macrophages and malignant cells, providing insights into potential therapeutic agents and their sensitivity characteristics. This comprehensive analysis positions the MHC.sig as a promising marker for predicting immune therapy outcomes and guiding combinatorial therapeutic strategies.

The Role and Clinical Relevance of Glycolysis-Associated Genes on Immune Infiltration in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) poses a significant challenge with dismal survival rates, necessitating a deeper understanding of its molecular mechanisms and the development of improved therapies. Metabolic reprogramming, particularly heightened glycolysis, plays a crucial role in HCC progression. Glycolysis-associated genes (GAGs) emerge as key players in HCC pathogenesis, influencing the tumor microenvironment and immune responses. This study aims to investigate the intricate interplay between GAGs and the immune landscape within HCC, offering valuable insights into potential prognostic markers and therapeutic targets to enhance treatment strategies and patient outcomes. Through the exploration of GAGs, we have identified two distinct molecular glycolytic subtypes in HCC patients, each exhibiting significant differences in both the immune microenvironment and prognosis. A risk model comprising five key GAGs was formulated and subsequently evaluated for their predictive accuracy. Our findings underscore the diverse tumor microenvironment and immune responses associated with the varying glycolytic subtypes observed in HCC. The identified key GAGs hold promise as prognostic indicators for evaluating HCC risk levels, predicting patient outcomes, and guiding clinical treatment decisions, particularly in the context of anticipating responses to immunotherapy drugs.

Outcomes of Human Leukocyte Antigen-Matched Related Donor and Haploidentical Allogeneic Hematopoietic Cell Transplantation Recipients by Immune Profiles of Recipients and Donors

Haploidentical (Haplo) allogeneic HCTs (alloHCT) have been used more frequently over the last decade as survival is similar to HLA-matched related donor (MRD) alloHCTs. We aimed to identify donor and recipient immune signatures before alloHCT that are associated with clinically meaningful outcomes in MRD vs Haplo alloHCT recipients. This retrospective cohort study of 165 MRD (n = 132) and Haplo (n = 33) alloHCT recipients and their related donors between 2007-2019 with paired peripheral blood samples immunophenotyped for T-cell, B-cell, NK cell and dendritic cell (DC) subsets. Immune cells were quantified before alloHCT in donors and recipients; calculations of immune cell ratios were classified as high, intermediate, and low and analyzed with alloHCT outcomes. Haplo donors were younger than MRD donors (median: 35 vs 51 years), whereas Haplo recipients were older than MRD recipients (median: 68 vs 54 years), were more likely to have a Karnofsky Performance Score ≤ 70 (76% vs 57%), 3+ comorbidities (54% vs 47%), and were in complete remission prior to alloHCT (58% vs 42%). In MRD alloHCT, a lower ratio of CD4+ to CD8+ effector memory cells in the donor was associated with lower 4-yr overall survival (OS; 25% vs 61%; P = .009), lower 4-yr progression free survival (PFS; 25% vs 58%; P = .014) and higher incidence of 1-yr transplant-related mortality (TRM; 39% vs 7%; P = .009) in recipients. A higher ratio of CD8+ effector memory to total NK cells measured in MRD recipients was associated with a higher incidence of grade II-IV aGvHD (63% vs 37%; P = .004) but was not statistically significant for III-IV aGvHD (23% vs 12%). In Haplo alloHCT, a lower ratio of total T-regulatory to CD4+ central memory cells in the donor was associated with lower 4-yr PFS (22% vs 60%; P = .0091). A higher ratio of CD4+ effector memory to CD8+ effector memory cells measured in Haplo recipients pre-alloHCT was associated with lower 4-yr OS (25% vs 88%; P = .0039). In both MRD and Haplo recipients, a higher ratio of CD4+ naïve to CD4+ central memory cells was associated with a higher incidence of grade II-IV aGvHD (64% vs 38%; P = .04). Evaluation of pre-alloHCT immune signatures of the donor and recipient may influence clinically meaningful patient outcomes in both MRD and Haplo transplants.

DOK1 and DOK2 regulate CD8 T cell signaling and memory formation without affecting tumor cell killing

Targeting intracellular inhibiting proteins has been revealed to be a promising strategy to improve CD8+ T cell anti-tumor efficacy. Here, we are focusing on intracellular inhibiting proteins specific to TCR signaling: DOK1 and DOK2 expressed in T cells. We hypothesized that depletion of intracellular inhibition checkpoint DOK1 and DOK2 could improve CD8+ T-cell based cancer therapies. To evaluate the role of DOK1 and DOK2 depletion in physiology and effector function of CD8+ T lymphocytes and in cancer progression, we established a transgenic T cell receptor mouse model specific to melanoma antigen hgp100 (pmel-1 TCR Tg) in WT and Dok1/Dok2 DKO (double KO) mice. We showed that both DOK1 and DOK2 depletion in CD8+ T cells after an in vitro pre-stimulation induced a higher percentage of effector memory T cells as well as an up regulation of TCR signaling cascade- induced by CD3 mAbs, including the increased levels of pAKT and pERK, two major phosphoproteins involved in T cell functions. Interestingly, this improved TCR signaling was not observed in naïve CD8+ T cells. Despite this enhanced TCR signaling essentially shown upon stimulation via CD3 mAbs, pre-stimulated Dok1/Dok2 DKO CD8+ T cells did not show any increase in their activation or cytotoxic capacities against melanoma cell line expressing hgp100 in vitro. Altogether we demonstrate here a novel aspect of the negative regulation by DOK1 and DOK2 proteins in CD8+ T cells. Indeed, our results allow us to conclude that DOK1 and DOK2 have an inhibitory role following long term T cell stimulations.