Mechanisms of natural killer cell-mediated cellular cytotoxicity

Discussion on the mechanism of HER2 resistance in esophagogastric junction and gastric cancer in the era of immunotherapy

Human epidermal growth factor receptor 2 (HER2) is a critical biomarker and therapeutic target in gastric/gastroesophageal junction (G/GEJ) cancers, despite the initial success of HER2-targeted therapies, such as trastuzumab, resistance to these drugs has emerged as a major impediment to effective long-term treatment. This review examines the mechanisms of drug resistance in HER2-positive G/GEJ cancer, the primary mechanisms of resistance explored include alterations in the HER2 receptor itself, such as mutations and changes in expression levels, as well as downstream signaling pathways, and interactions with the tumor microenvironment (TME). Furthermore, the review discusses the Novel therapeutic approaches, including the use of antibody-drug conjugates (ADCs) and combination therapies are assessed for their potential to enhance outcomes. By integrating recent research findings and clinical trials, this review aims to provide oncologists and researchers with insights into developing more effective treatments for patients with drug-resistant HER2-positive G/GEJ cancer.

Deciphering distinct pathogenic mechanisms of ankylosing spondylitis and systemic sclerosis via shared biomarkers ZSWIM6 and CCL3L3: Insights from an integrative bioinformatics approach

Ankylosing Spondylitis (AS) and Systemic Sclerosis (SSc) are both autoimmune diseases, albeit with distinct anatomical targets. AS primarily affects the spine and sacroiliac joints, triggering inflammation and eventual fusion of the vertebrae. SSc predominantly impacts the skin and connective tissues, leading to skin fibrosis, thickening, and potential damage to vital organs such as the lungs, heart, and kidneys. Despite their differing anatomical manifestations, inflammation serves as a pivotal factor in both conditions. Exploring the causes of the different pathogenesis of inflammation in AS and SSc could provide new insights into their treatment. We selected RNA-seq profiles of peripheral blood mononuclear cells (PBMCs) from the GEO datasets GSE73754 and GSE19617. DEGs were identified using the Limma R package with an adjusted p-value cutoff of < 0.05. Gene Ontology pathway analysis, SVM recursive feature elimination, and Gene Set Enrichment Analysis (GSEA) were conducted to analyze the DEGs. CIBERSORT was applied to estimate immune cell composition and its correlation with hub genes. Single-cell RNA sequencing data from peripheral blood mononuclear cells in the GSE194315 dataset were included to support differential expression analysis and biomarker identification. Additionally, single-cell RNA sequencing data from bone marrow blood samples were utilized to further validate these findings, offering complementary insights into biomarker expression across distinct sample types. A total of 762 DEGs were identified between AS patients and controls, and 441 DEGs between SSc patients and controls. Both conditions showed enrichment in the Natural killer cell mediated cytotoxicity pathway. ZSWIM6 and CCL3L3 were identified as potential biomarkers in AS and SSc, with significant diagnostic capabilities demonstrated by ROC analysis. Correlation analysis revealed associations between these biomarkers and specific immune cell types. The study utilizing ZSWIM6 and CCL3L3 as potential biomarkers provides deep insights into the distinct molecular mechanisms of SSc and AS. These findings lay the foundation for future research on targeted therapies and enhance our understanding of immune cell interactions in these autoimmune diseases.

Advances in research on flavonoids in tumor immunotherapy (Review)

Cancer immunotherapy is an approach used in anti‑tumor treatment; however, its efficacy is limited to specific tumor types that are inherently sensitive to immune system modulation. Expanding the scope of indications and enhancing the efficacy of cancer immunotherapy are key goals for continued advancement. Flavonoids modulate the tumor‑immunosuppressive microenvironment. Integrating flavonoids with immunotherapeutic modalities, including cancer vaccines, immune checkpoint inhibitors and adoptive immune‑cell therapy, has potential in terms of augmenting the therapeutic efficacy of immunotherapy. The present review aimed to summarize flavonoids that enhance cancer immunotherapy, focusing on their underlying mechanisms and the application of nanotechnology to overcome inherent limitations such as poor solubility, low bioavailability, rapid metabolism, and instability under physiological conditions, thereby highlighting the potential of flavonoids in advancing cancer immunotherapy.

Enhanced in vitro transfection efficiency of mRNA-loaded polyplexes into natural killer cells through osmoregulation

High expression of externally injected in vitro transcribed (IVT) mRNA in natural killer (NK) cells is a prerequisite for NK cell-mediated cell therapy. To enhance the transfection efficacy of IVT mRNA-loaded polyplexes, we exposed NK cells to a hypertonic condition during transfection, which facilitated endo/exocytosis to maintain the isotonic state of the cells. The transfection efficacy of IVT mRNA was significantly enhanced after 24 h, which was mainly due to the facilitated cellular uptake and endosomal escape of the polyplexes. Interestingly, osmotic alterations in NK cells significantly affect the expression levels of endosome-escape-related genes in ion channels. Treatment with a mild hypertonic condition exhibited negligible toxicity to NK cells, without disturbing the integrity of the cellular membranes or the innate cytotoxic abilities of NK cells against cancer cells. These results demonstrate that the hypertonic treatment of NK cells enhances the transfection efficacy of IVT mRNA to produce genetically engineered NK cells.

Targeting EGFR-TKI resistance in lung cancer: Role of miR-5193/miR-149-5p loaded NK-EVs and Carboplatin combination

Lung cancer remains the leading cause of cancer-related deaths, and there is an urgent need for innovative therapies. MicroRNA (miRNA)-based gene therapy has shown promise, but efficient delivery systems are required for its success. This study investigates the use of extracellular vehicles (EVs) secreted by natural killer (NK) cells as delivery systems for miRNAs targeting PD-L1/PD-1 immune checkpoint and FOXM1, in combination with Carboplatin, to enhance anticancer efficacy in lung cancer models. NK-EVs were isolated from NK92-MI cells and characterized using nanoparticle tracking analysis (NTA), proteomics and Western blotting, confirming their exosomal characteristics. Gene ontology profiling and RNA-seq identified highly expressed miRNAs such as miR-5193 and miR-149-5p, which were loaded into NK-EVs via electroporation. Agarose gel electrophoresis confirmed their entrapment and Quickdrop spectrophotometer was used to estimate the quantity. In vitro, miRNA-loaded NK-EVs demonstrated significant cytotoxicity against Osimertinib-resistant PDX (TM0019, Jackson Labs) and H1975R (with L858R mutations) lung cancer cells, with approximately 1.2 to 1.6-fold (p < 0.01) decrease in cell viability compared to NK-EVs alone. In vivo, the combination of miRNA-loaded NK-EVs and Carboplatin significantly reduced tumor volumes (3.5 to 4-fold, p < 0.001) in PDX and H1975R xenograft models, with the most pronounced effect observed in combination therapies. Western blot analysis showed downregulation of tumor-associated markers: PD-1/PD-L1, FOXM1, Survivin, NF-κB and others vs untreated group, p < 0.001) suggesting immune checkpoint inhibition, apoptosis and anti-inflammatory activity. These findings highlight the potential of NK-EVs as effective carriers for miRNAs in combination with chemotherapy, offering a promising therapeutic strategy for NSCLC with EGFR mutations.

Fc gamma receptor polymorphisms in antibody therapy: implications for bioassay development to enhance product quality

The effectiveness of therapeutic antibodies is often associated with their Fc-mediated effector functions, such as antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis. These functions rely on interactions between Fc gamma receptors (FcγRs) on immune cells and the Fc region of antibodies. Genetic variations in these receptors, known as FcγR polymorphisms, can influence therapeutic outcomes by altering receptor expression levels, affinity, and function. This review examines the impact of FcγR polymorphisms on antibody therapy, emphasizing their role in developing and optimizing functional bioassays to assess product quality. Understanding these polymorphisms is essential for refining bioassays, which are crucial for accurately characterizing antibody products and ensuring consistency in manufacturing processes.

Spatial statistics of submicron size clusters of activating and inhibitory Natural Killer cell receptors in the resting state regulate early time signal discrimination

Natural Killer (NK) cells are lymphocytes of the innate immunity and sense healthy or diseased target cells with activating and inhibitory NK cell receptor (NKR) molecules expressed on the cell surface. The protection provided by NK cells against viral infections and tumors critically depends on their ability to distinguish healthy cells from diseased target cells that express 100- fold more activating ligands. NK cell signaling and activation depend on integrating opposing signals initiated by activating and inhibitory NKRs interacting with the cognate ligands expressed on target cells. A wide range of imaging experiments have demonstrated aggregation of both activating and inhibitory NKRs in the plasma membrane on submicron scales in resting NK cells. How do these submicron size NKR clusters formed in the resting state affect signal discrimination? Using in silico mechanistic signaling modeling with information theory and published superresolution imaging data for two well-studied human NKRs, activating NKG2D and inhibitory KIR2DL1, we show that early time signal discrimination by NK cells depends on the spatial statistics of these clusters. When NKG2D and KIR2DL1 clusters are disjoint in the resting state, these clusters help NK cells to discriminate between target cells expressing low and high doses of the activating cognate ligand, whereas, when the NKR clusters fully overlap the NK cells are unable to distinguish between healthy and diseased target cells. Therefore, the spatial statistics of submicron scale clusters of activating and inhibitory NKRs at the resting state provides an additional layer of control for signal discrimination in NK cells.

Significance

Signal integration of opposing signals initiated by activating and inhibitory NK cell receptors (NKRs) in a noisy environment determine an NK cell's response to healthy and diseased target cells. Superresolution microscopy imaging revealed aggregation of NKRs in submicron scales in resting NK cells. Using computational modeling, information theory, and published imaging data, we show when these clusters of the opposing NKRs are disjoint, the NK cells can separate healthy from diseased target cells but fail to do so when the clusters overlap. Thus, spatial statistics of submicron-sized NKR clusters in the resting state provide a lever for distinguishing self from non-self. The results suggest spatial organization of receptors in the resting state in may modulate signal discrimination in immune cells.

Oxidative phosphorylation and breast cancer progression: insights into PGC-1α's role in mitochondrial function

Breast cancer still ranks high as a leading cause of mortality in women due to its complex relationship with metabolic reprogramming and tumor progression. The peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), a key transcriptional coactivator regulating mitochondrial biogenesis and oxidative phosphorylation (OXPHOS), plays a dual role in breast cancer metabolism. On the one hand, PGC-1α enhances mitochondrial function and energy production, facilitating tumor survival and metastasis, particularly in hypoxic environments. On the other hand, its suppression can limit tumor aggressiveness and energy metabolism. This dual functionality underscores its context-dependent role in cancer progression, where its activation or inhibition varies across tumor subtypes and microenvironmental conditions. The purpose of this review is to provide a comprehensive understanding of PGC-1α's dual roles in breast cancer, elucidating its regulation of mitochondrial function, its contribution to tumor progression, and the therapeutic implications of targeting this key metabolic regulator.

Axl Regulation of NK Cell Activity Creates an Immunosuppressive Tumor Immune Microenvironment in Head and Neck Cancer

Background: Head and neck cancer (HNC) evades immune responses by manipulating the tumor immune microenvironment (TIME). Tumor-bound Axl has been implicated in promoting an immunosuppressive TIME in HNC, though its precise role remains unclear. Understanding Axl's contribution to immune evasion in HNC could lead to the identification of new therapeutic targets; therapies directed at these targets could be combined with and thereby enhance immunotherapies. Results: Using Axl knockout (Axl KO) cell lines derived from the immunologically "cold" MOC2 mouse model, we found that Axl loss delayed tumor growth in immunocompetent mice. This was accompanied by reduced immunosuppressive cells, including MDSCs, Tregs, B cells, and neutrophils, and increased infiltration of cytotoxic CD8 T cells and NK cells. To identify the immune population(s) responsible for these changes, Axl KO tumors were implanted in immune-deficient mice. Axl KO tumor growth in athymic nude mice (which lack T cells) was unchanged, whereas tumor growth in NCG mice (which lack NK cells) was rescued, suggesting that NK cells mediate the Axl KO tumor growth delay. Further, Axl loss enhanced NK cell cytotoxicity in vitro and in vivo, and NK cell depletion reversed delayed Axl KO tumor growth. Mechanistically, Axl KO tumors showed decreased expression of CD73 and CCL2, which inhibit NK cells, and increased expression of CCL5 and CXCL10, which promote NK cell recruitment and activation. Conclusions: These novel findings suggest that tumor-bound Axl fosters an immunosuppressive TIME by inhibiting NK cell recruitment and function, thereby promoting tumor growth. Targeting Axl may enhance NK cell-mediated tumor killing and improve immunotherapy efficacy in HNC.

Advancing Natural Killer Cell Therapy: Genetic Engineering Strategies for Enhanced Cancer Immunotherapy

Natural killer (NK) cells are pivotal innate immune system components that exhibit spontaneous cytolytic activity against abnormal cells, such as infected and tumor cells. NK cells have shown significant promise in adoptive cell therapy because of their favorable safety profiles and minimal toxicity in clinical settings. Despite their advantages, the therapeutic application of unmodified NK cells faces challenges, including limited in vivo persistence, particularly in the immunosuppressive tumor microenvironment. Recent advances in genetic engineering have enhanced the therapeutic potential of NK cells by addressing these limitations and improving their therapeutic efficacy. In this review, we have described various methodologies for the genetic modification of NK cells, including viral vectors, electroporation, and nanoparticle-based approaches. The ongoing research on nanomaterialbased approaches highlights their potential to overcome current limitations in NK cell therapy, paving the way for advanced cancer therapy and improved clinical outcomes. In this review, we also emphasize the potential of engineered NK cells in cancer immunotherapy and other clinical applications, highlighting the expanding scope of NK cell-based treatments and the critical role of innovative genetic engineering techniques.

Exploration of key genes associated with oxidative stress in polycystic ovary syndrome and experimental validation

Introduction

The current study demonstrated that oxidative stress (OS) is closely related to the pathogenesis of polycystic ovary syndrome (PCOS). However, there are numerous factors that lead to OS, therefore, identifying the key genes associated with PCOS that contribute to OS is crucial for elucidating the pathogenesis of PCOS and selecting appropriate treatment strategies.

Methods

Four datasets (GSE95728, GSE106724, GSE138572, and GSE145296) were downloaded from the gene expression omnibus (GEO) database. GSE95728 and GSE106724 were combined to identify differentially expressed genes (DEGs) in PCOS. weighted gene correlation network analysis (WGCNA) was used to screen key module genes associated with PCOS. Differentially expressed OS related genes (DE-OSRGs) associated with PCOS were obtained by overlapping DEGs, key module genes, and OSRGs. Subsequently, the optimal machine model was obtained to identify key genes by comparing the performance of the random forest model (RF), support vector machine model (SVM), and generalized linear model (GLM). The molecular networks were constructed to reveal the non-coding regulatory mechanisms of key genes based on GSE138572 and GSE145296. The Drug-Gene Interaction Database (DGIdb) was used to predict the potential therapeutic agents of key genes for PCOS. Finally, the expression of key OSRGs was validated by RT-PCR.

Results

In this study, 8 DE-OSRGs were identified. Based on the residuals and root mean square error of the three models, the best performance of RF was derived and 7 key genes (TNFSF10, CBL, IFNG, CP, CASP8, APOA1, and DDIT3) were identified. The GSEA enrichment analysis revealed that TNFSF10, CP, DDIT3, and INFG are all enriched in the NOD-like receptor signaling pathway and natural killer cell-mediated cytotoxicity pathways. The molecular regulatory network uncovered that both TNFSF10 and CBL are regulated by non-coding RNAs. Additionally, 70 potential therapeutic drugs for PCOS were predicted, with ibuprofen associated with DDIT3 and IFNG. RT-qPCR validation confirmed the expression trends of key genes IFNG, DDIT3, and APOA1 were consistent with the dataset, and the observed differences were statistically significant (P < 0.05).

Conclusion

The identification of seven key genes and molecular regulatory networks through bioinformatics analysis is of great significance for exploring the pathogenesis and therapeutic strategies of PCOS.

Supplementation with heat-sterilized Lactobacillus crispatus strain KT-11 stimulates the T cell-related immune function of healthy Japanese adults: A pilot randomized, placebo-controlled, double-blind, parallel-group study

Viral infections are a global public health threat, reaffirming the importance of immune function. We previously identified Lactobacillus crispatus strain KT-11 (KT-11) and found that heat-sterilized KT-11 affect counts of T cell and dendritic cell in vitro, as well as promoted immunoglobulin A production and prevented weight loss caused by influenza virus infection in vivo. It was hypothesized that heat-sterilized KT-11 affects immune cell count/activity even in healthy individuals. We conducted a pilot study to examine the design to verify the effects of heat-sterilized KT-11 supplementation on immune cell count/activity and physical condition. This was a pilot randomized, double-blind, placebo-controlled, parallel-group study including 22 healthy adults who consumed either KT-11 or placebo for 4 weeks. Immunological status (immune cell count/activity and its score) and various immune-related indicators including SARS-CoV-2 immunoglobulin G antibody were assessed, and a physical condition questionnaire was administered. The primary outcome was immune cell count/activity (T cell subsets, B cell, natural killer cell) and overall immunological status score after 4 weeks. Two patients were excluded because of noncompliance; the final analysis included 20 participants (10 participants/group). The KT-11 group had a significantly higher CD3+ T cell count versus placebo group. The female subgroup also had a significantly higher CD8+CD28+ T cell count. Although the KT-11 group showed no changes in SARS-CoV-2 immunoglobulin G titer, it had fewer self-reported common cold-like symptoms, particularly fatigue. This pilot study showed that KT-11 affected immune cell profiles, suggesting that the feasibility of a verification study. This trial was registered at UMIN Clinical Trials Registry (UMIN000046991).

FCGR2C Q13 and FCGR3A V176 alleles jointly associate with worse natural killer cell-mediated antibody-dependent cellular cytotoxicity and microvascular inflammation in kidney allograft antibody-mediated rejection

Natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity (ADCC) is a major mechanism of humoral allograft injury. FCGR3A V176/F176 polymorphism influences ADCC activity. Additionally, NK cell FcγRIIc expression, dictated by the Q13/STP13 polymorphism, was never investigated in kidney transplantation. To assess the clinical relevance of FCGR2C Q13/STP13 polymorphism in conjunction with FCGR3A V176/F176 polymorphism, 242 kidney transplant recipients were genotyped. NK cell Fc gamma receptor (FcγR) expression and ADCC activity were assessed. RNA sequencing was performed on kidney allograft biopsies to explore the presence of infiltrating FcγR+ NK cells. The FCGR2C Q13 allele was enriched in antibody-mediated rejection patients. FcγRIIc Q13+ NK cells had higher ADCC activity than FcγRIIc Q13- NK cells. In combination with the high-affinity FCGR3A V176 allele, Q13+V176+ NK cells were the most functionally potent. Q13+ was associated with worse microvascular inflammation and a higher risk of allograft loss. Among V176- patients, previously described in the literature as lower-risk patients, Q13+V176- showed a lower graft survival than Q13-V176- patients. In antibody-mediated rejection biopsies, FCGR2C transcripts were enriched and associated with ADCC-related transcripts. Our results suggest that FCGR2C Q13 in addition to FCGR3A V176 is a significant risk allele that may enhance NK cell-mediated ADCC and contribute to allograft injury and poor survival.

Prognostic significance of perioperative circulating CD56bright NK cell and recovery of NK cell activity in patients with colorectal cancer undergoing radical surgery

INTRODUCTION

Natural killer (NK) cell activity (NKA) is downregulated in patients with colorectal cancer (CRC), and its dysfunction is possibly associated with increased risk of recurrence. However, its role in prognosis of CRC remains unclear. Prior research has shown that surgical stress can suppress NKA. This study explores the relationship between NK cell/NKA and clinicopathological factors during the perioperative period in patients with CRC.

METHODS

We prospectively enrolled 45 patients with CRC. Venous blood samples were collected preoperatively and on postoperative day 3 (POD3) and 30 (POD30). NKA was assessed by measuring the plasma levels of NK cell-secreted IFN-γ.

RESULTS

NKA was significantly reduced on POD3 compared with baseline levels before surgery but showed significant recovery by POD30. NKA on POD30 was considerably higher in patients with advanced disease stages or one or more high-risk preoperative factors. Additionally, a higher NKA recovery in patients with advanced stage exhibited improved recurrence-free survival (RFS) and progression-free survival (PFS) (hazards ratio (HR): 0.2442). Furthermore, an increased percentage of CD56bright NK cells and a higher CD56bright/CD56dim NK cell ratio postoperatively on POD30 were associated with better RFS/PFS (HR: 0.2732, P = 0.0433 and HR: 0.2193, P = 0.024, respectively).

CONCLUSIONS

Our findings indicate that a notable postoperative increase in CD56bright NK cells on POD30, both in percentage and ratio, correlates with a more favorable prognosis in CRC patients. Additionally, higher recovery rates of NKA in patients with advanced stages may offer potential applications in risk stratification and the development of treatment strategies for CRC.

Circulatory age-associated B cells: Their distinct transcriptomic characteristics and clinical significance in drug-naïve patients with rheumatoid arthritis

Age-associated B cells (ABCs) have been implicated in the pathogenesis of autoimmune diseases. However, the global gene expression and clinical significance of circulatory ABCs in rheumatoid arthritis (RA) remain poorly understood. Here, single-cell RNA sequencing identified nine B cell subsets in peripheral blood of RA patients, including ABCs. Increased phagocytosis and antigen presentation were functionally enriched by the genes expressed differentially in ABCs. Network analysis and in vitro experiments demonstrated SYK as a key regulator defining the myeloid-like phenotypes in ABCs. Flow cytometry showed that the proportion of ABCs correlated with RA activity and serum tumor necrosis factor-alpha level. Notably, ABCs above a cutoff threshold specifically distinguished RA from healthy controls and indicated higher disease activity. This study highlights the myeloid characteristics of circulatory ABCs regulated by SYK in RA. Increased ABCs may reflect disease activity and could serve as a potential biomarker in RA.

Hypoxia as a critical player in extracellular vesicles-mediated intercellular communication between tumor cells and their surrounding microenvironment

In the past years, increasing attention has been paid to the role of extracellular vesicles (EVs) as mediators of intercellular communication in cancer. These small size particles mediate the intercellular transfer of important bioactive molecules involved in malignant initiation and progression. Hypoxia, or low partial pressure of oxygen, is recognized as a remarkable feature of solid tumors and has been demonstrated to exert a profound impact on tumor prognosis and therapeutic efficacy. Indeed, the high-pitched growth rate and chaotic neovascular architecture that embodies solid tumors results in a profound reduction in oxygen pressure within the tumor microenvironment (TME). In response to oxygen-deprived conditions, tumor cells and their surrounding milieu develop homeostatic adaptation mechanisms that contribute to the establishment of a pro-tumoral phenotype. Latest evidence suggests that the hypoxic microenvironment that surrounds the tumor bulk may be a clincher for the observed elevated levels of circulating EVs in cancer patients. Thus, it is proposed that EVs may play a role in mediating intercellular communication in response to hypoxic conditions. This review focuses on the EVs-mediated crosstalk that is established between tumor cells and their surrounding immune, endothelial, and stromal cell populations, within the hypoxic TME.

Adipokines in Breast Cancer: Decoding Genetic and Proteomic Mechanisms Underlying Migration, Invasion, and Proliferation

Background

Adipokines, bioactive peptides secreted by adipose tissue, appear to contribute to breast cancer development and progression. While numerous studies suggest their role in promoting tumor growth, the exact mechanisms of their involvement are not yet completely understood.

Methods

In this project, varying concentrations of recombinant human adipokines (Leptin, Lipocalin-2, PAI-1, and Resistin) were used to study their effects on four selected breast cancer cell lines (EVSA-T, MCF-7, MDA-MB-231, and SK-Br-3). Over a five-day proliferation phase, linear growth was assessed by calculating doubling times and malignancy-associated changes in gene and protein expression were identified using quantitative TaqMan real-time PCR and multiplex protein analysis. Migration and invasion behaviors were quantified using specialized Boyden chamber assays.

Results

We found significant, adipokine-mediated genetic and proteomic alterations, with PCR showing an up to 6-fold increase of numerous malignancy-associated genes after adipokine-supplementation. Adipokines further altered protein secretion, such as raising the concentrations of different tumor-associated proteins up to 13-fold. Effects on proliferation varied, however, with most approaches showing significant enhancement in growth kinetics. A concentration-dependent increase in migration and invasion was generally observed, with no significant reductions in any approaches.

Conclusion

We could show a robust promoting effect of several adipokines on different breast cancer cells in vitro. Understanding the interaction between adipose tissue and breast cancer cells opens potential avenues for innovative breast cancer prevention and therapy strategies. Our findings indicate that antibodies against specific adipokines could become a beneficial component of clinical breast cancer treatment in the future.

Enhanced Immune Functions of In Vitro Human Natural Killer Cells and Splenocytes in Immunosuppressed Mice Supplemented with Mature Silkworm Products

OBJECTIVES

The immune-enhancing properties of steamed mature silkworm, known as HongJam (HJ), were investigated using human interleukin-2-independent Natural Killer 92 (NK92-MI) cells and a cyclophosphamide intraperitoneal injection-induced immunosuppressed mice model (CPA-IP). White Jade variety mature silkworm HJ (WJ-HJ) was used to prepare WJ-HJ supercritical fluid extracts (WJ-SCE) and WJ-HJ-supplemented feeds.

RESULTS

Treatment with WJ-SCE significantly enhanced proliferation, migration, and cytotoxicity of NK92-MI cells against various cancer cells while improving mitochondrial function and ATP production (p < 0.05). In CPA-IP mice, consumption of WJ-HJ-supplemented feeds restored immune function by improving body weight, immune organ indices, immunoglobulin levels, and blood cytokines. Splenocyte proliferation and cytotoxicity were significantly elevated in both saline intraperitoneal injection (Sal-IP) and CPA-IP groups with WJ-HJ supplementation, independent of mitogen activation (p < 0.05).

CONCLUSIONS

These results suggest that WJ-HJ enhances immune modulation and immune surveillance functions of NK cells by improving mitochondrial and cytotoxic functions. WJ-HJ holds promise as a functional food for immune enhancement, pending clinical validation.

MiR-216a-3p inhibits the cytotoxicity of primary natural killer cells

Introduction

The role of miRNAs in regulating variable molecular functions has been sought by scientists for its promising utility in regulating the immune response and, hence, in treating various diseases. In hepatocellular carcinoma (HCC) specifically, a reduction in the number and efficiency of circulating and intrahepatic natural killer (NK) cells has been reported. Our project aims to investigate the role of miR-216a-3p in the regulation of NK cell cytotoxicity, especially since it plays a tumor suppressor role in the context of HCC.

Methods

To achieve our aim, we isolated NK cells from the whole blood of 86 patients with HCC and 23 healthy controls. We assessed the expression profile of miR-216a-3p in NK cells of patients and controls. Furthermore, we induced the expression of miR-216a-3p in NK cells isolated from healthy controls, followed by measuring the release of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), perforins (PRF) and granzyme B (GrB) using ELISA as well as NK cells cytolytic activity against Huh7 cells using lactate dehydrogenase (LDH) cytotoxicity assay. After that, we performed an in silico analysis to understand the mechanistic regulation imposed by miR-216a-3p on NK cells to study its impact on one of its potential downstream targets.

Results

Our results have indicated that miR-216a-3p has higher expression in NK cells of patients with HCC, and simulating this elevated expression pattern via forcing miR-216a-3p expression in normal NK cells has negatively impacted the release of TNF- α, IFN- γ, GrB, and PRF. Consequently, a decrease in cell cytolysis was observed. Our in silico analysis revealed that the predicted downstream targets of miR-216a-3p are enriched in the FOXO-signaling pathway. Among those targets is FOXO-1, which has been reported to play a role in NK cell maturation. Thus, we evaluated FOXO-1 expression upon mimicking miR-216a-3p in control NK cells that showed significant downregulation of FOXO-1 on both RNA and protein levels.

Conclusion

In conclusion, we report miR-216-3p as a negative regulator of NK cell cytotoxicity.

Pulmonary delivery of silver nanoparticles prevents influenza infection by recruiting and activating lymphoid cells

Silver nanoparticles (AgNPs) are a potential antiviral agent due to their ability to disrupt the viral particle or alter the virus metabolism inside the host cell. In vitro, AgNPs exhibit antiviral activity against the most common human respiratory viruses. However, their capacity to modulate immune responses during respiratory viral infections has yet to be explored. This study demonstrates that administering AgNPs directly into the lungs prior to infection can reduce viral loads and therefore virus-induced cytokines in mice infected with influenza virus or murine pneumonia virus. The prophylactic effect was diminished in mice with depleted lymphoid cells. We showed that AgNPs-treatment resulted in the recruitment and activation of lymphocytes in the lungs, particularly natural killer (NK) cells. Mechanistically, AgNPs enhanced the ability of alveolar macrophages to promote both NK cell migration and IFN-γ production. By contrast, following infection, in mice treated with AgNPs, NK cells exhibited decreased activation, indicating that these nanoparticles can regulate the potentially deleterious activation of these cells. Overall, the data suggest that AgNPs may possess prophylactic antiviral properties by recruiting and controlling the activation of lymphoid cells through interaction with alveolar macrophages.

M6A-mediated molecular patterns and tumor microenvironment infiltration characterization in nasopharyngeal carcinoma

N6-methyladenosine (m6A) is the most predominant RNA epigenetic regulation in eukaryotic cells. Numerous evidence revealed that m6A modification exerts a crucial role in the regulation of tumor microenvironment (TME) cell infiltration in several tumors. Nevertheless, the potential role and mechanism of m6A modification in nasopharyngeal carcinoma (NPC) remains unknown. mRNA expression data and clinical information from GSE102349, and GSE53819 datasets obtained from Gene Expression Omnibus (GEO) was used for differential gene expression and subsequent analysis. Consensus clustering was used to identify m6A-related molecular patterns of 88 NPC samples based on prognostic m6A regulators using Univariate Cox analysis. The TME cell-infiltrating characteristics of each m6A-related subclass were explored using single-sample gene set enrichment (ssGSEA) algorithm and CIBERSORT algotithm. DEGs between two m6A-related subclasses were screened using edgeR package. The prognostic signature and predicated nomogram were constructed based on the m6A-related DEGs. The cell infiltration and expression of prognostic signature in NPC was determined using immunohistochemistry (IHC) analysis. Chi-square test was used to analysis the significance of difference of the categorical variables. And survival analysis was performed using Kaplan-Meier plots and log-rank tests. The NPC samples were divided into two m6A-related subclasses. The TME cell-infiltrating characteristics analyses indicated that cluster 1 is characterized by immune-related and metabolism pathways activation, better response to anit-PD1 and anti-CTLA4 treatment and chemotherapy. And cluster 2 is characterized by stromal activation, low expression of HLA family and immune checkpoints, and a worse response to anti-PD1 and anti-CTLA4 treatment and chemotherapy. Furthermore, we identified 1558 DEGs between two m6A-related subclasses and constructed prognostic signatures to predicate the progression-free survival (PFS) for NPC patients. Compared to non-tumor samples, REEP2, TMSB15A, DSEL, and ID4 were upregulated in NPC samples. High expression of REEP2 and TMSB15A showed poor survival in NPC patients. The interaction between REEP2, TMSB15A, DSEL, ID4, and m6A regulators was detected. Our finding indicated that m6A modification plays an important role in the regulation of TME heterogeneity and complexity.

Unraveling the copper-death connection: Decoding COVID-19's immune landscape through advanced bioinformatics and machine learning approaches

This study aims to analyze Coronavirus Disease 2019 (COVID-19)-associated copper-death genes using the Gene Expression Omnibus (GEO) dataset and machine learning, exploring their immune microenvironment correlation and underlying mechanisms. Utilizing GEO, we analyzed the GSE217948 dataset with control samples. Differential expression analysis identified 16 differentially expressed copper-death genes, and Cell type Identification By Estimating Relative Subsets Of RNA Transcripts (CIBERSORT) quantified immune cell infiltration. Gene classification yielded two copper-death clusters, with Weighted Gene Co-expression Network Analysis (WGCNA) identifying key module genes. Machine learning models (random forest, Support Vector Machine (SVM), Generalized Linear Model (GLM), eXtreme Gradient Boosting (XGBoost)) selected 6 feature genes validated by the GSE213313 dataset. Ferredoxin 1 (FDX1) emerged as the top gene, corroborated by Area Under the Curve (AUC) analysis. Gene Set Enrichment Analysis (GSEA) and Gene Set Variation Analysis (GSVA) revealed enriched pathways in T cell receptor, natural killer cytotoxicity, and Peroxisome Proliferator-Activated Receptor (PPAR). We uncovered differentially expressed copper-death genes and immune infiltration differences, notably CD8 T cells and M0 macrophages. Clustering identified modules with potential implications for COVID-19. Machine learning models effectively predicted COVID-19 risk, with FDX1's pivotal role validated. FDX1's high expression was associated with immune pathways, suggesting its role in COVID-19 pathogenesis. This comprehensive approach elucidated COVID-19-related copper-death genes, their immune context, and risk prediction potential. FDX1's connection to immune pathways offers insights into COVID-19 mechanisms and therapy.

Elevated Galectin-3 levels in the tumor microenvironment of ovarian cancer - implication of ROS mediated suppression of NK cell antitumor response via tumor-associated neutrophils

Introduction

Ovarian cancer is a lethal disease with low survival rates for women diagnosed in advanced stages. Current cancer immunotherapies are not efficient in ovarian cancer, and there is therefore a significant need for novel treatment options. The β-galactoside-binding lectin, Galectin-3, is involved in different immune processes and has been associated with poor outcome in various cancer diagnoses. Here, we investigated how Galectin-3 affects the interaction between natural killer (NK) cells and neutrophils in the tumor microenvironment of ovarian cancer.

Method

Ascites from the metastatic tumor microenvironment and cyst fluid from the primary tumor site were collected from patients with high-grade serous carcinoma (HGSC) together with peripheral blood samples. Galectin-3 concentration was measured in ascites, cyst fluid and serum or plasma. Neutrophils isolated from HGSC ascites and autologous blood were analyzed to evaluate priming status and production of reactive oxygen species. In vitro co-culture assays with NK cells, neutrophils and K562 target cells (cancer cell line) were conducted to evaluate NK cell viability, degranulation and cytotoxicity.

Results

High levels of Galectin-3 were observed in cyst fluid and ascites from patients with HGSC. Neutrophils present in HGSC ascites showed signs of priming; however, the priming status varied greatly among the patient samples. Galectin-3 induced production of reactive oxygen species in ascites neutrophils, but only from a fraction of the patient samples, which is in line with the heterogenous priming status of the ascites neutrophils. In co-cultures with NK cells and K562 target cells, we observed that Galectin-3-induced production of reactive oxygen species in neutrophils resulted in decreased NK cell viability and lowered anti-tumor responses.

Conclusion

Taken together, our results demonstrate high levels of Galectin-3 in the tumormicroenvironment of HGSC. High levels of Galectin-3 may induce production of reactiveoxygen species in ascites neutrophils in some patients. In turn, reactive oxygen species produced by neutrophils may modulate the NK cell anti-tumor immunity. Together, this study suggests further investigation to evaluate if a Galectin-3-targeting therapy may be used in ovarian cancer.

Enhancing Anti-Cancer Immune Response by Acidosis-Sensitive Nanobody Display

One of the main challenges with many cancer immunotherapies is that biomarkers are needed for targeting. These biomarkers are often associated with tumors but are not specific to a particular tumor and can lead to damage in healthy tissues, resistance to treatment, or the need for customization for different types of cancer due to variations in targets. A promising alternative approach is to target the acidic microenvironment found in most solid tumor types. This can be achieved using the pH (Low) Insertion Peptide (pHLIP), which inserts selectively into cell membranes under acidic conditions, sparing healthy tissues. pHLIP has shown potential for imaging, drug delivery, and surface display. For instance, we previously used pHLIP to display epitopes on the surfaces of cancer cells, enabling antibody-mediated immune cell recruitment and selective killing of cancer cells. In this study, we further explored this concept by directly fusing an anti-CD16 nanobody, which activates natural killer (NK) cells, to pHLIP, eliminating the need for antibody recruitment. Our results demonstrated the insertion of pH-sensitive agents into cancer cells, activation of the CD16 receptor on effector cells, and successful targeting and destruction of cancer cells by high-affinity CD16+ NK cells in two cancer cell lines.

SARS-CoV-2 infection induces adaptive NK cell responses by spike protein-mediated induction of HLA-E expression

HLA-E expression plays a central role for modulation of NK cell function by interaction with inhibitory NKG2A and stimulatory NKG2C receptors on canonical and adaptive NK cells, respectively. Here, we demonstrate that infection of human primary lung tissue with SARS-CoV-2 leads to increased HLA-E expression and show that processing of the peptide YLQPRTFLL from the spike protein is primarily responsible for the strong, dose-dependent increase of HLA-E. Targeting the peptide site within the spike protein revealed that a single point mutation was sufficient to abrogate the increase in HLA-E expression. Spike-mediated induction of HLA-E differentially affected NK cell function: whereas degranulation, IFN-γ production, and target cell cytotoxicity were enhanced in NKG2C+ adaptive NK cells, effector functions were inhibited in NKG2A+ canonical NK cells. Analysis of a cohort of COVID-19 patients in the acute phase of infection revealed that adaptive NK cells were induced irrespective of the HCMV status, challenging the paradigm that adaptive NK cells are only generated during HCMV infection. During the first week of hospitalization, patients exhibited a selective increase of early NKG2C+CD57- adaptive NK cells whereas mature NKG2C+CD57+ cells remained unchanged. Further analysis of recovered patients suggested that the adaptive NK cell response is primarily driven by a wave of early adaptive NK cells during acute infection that wanes once the infection is cleared. Together, this study suggests that NK cell responses to SARS-CoV-2 infection are majorly influenced by the balance between canonical and adaptive NK cells via the HLA-E/NKG2A/C axis.

Immunogenicity risk assessment of empty capsids present in adeno-associated viral vectors using predictive innate immune responses

Immunogenicity of gene therapy and the impacts on safety and efficacy are of increasing interest in the pharmaceutical industry. Unique structural aspects of gene therapy delivery vectors, such as adeno-associated viral (AAV) vectors, are expected to activate the innate immune system. The risk of innate immune activation is critical to understand due to the potential impacts on safety and on subsequent adaptive immune responses. In this study, we investigated the responses of key innate immune players-dendritic cells, natural killer (NK) cells, and the complement system-to AAV8 capsids. Immunogenicity risk was also predicted in the presence empty AAV capsids for AAV gene therapy. Compared to genome-containing "full" AAV8 capsids, empty AAV8 capsids more strongly induced proinflammatory cytokine production and migration by human and mouse dendritic cells, but the "full" capsid increased expression of co-stimulatory markers. Furthermore, in an NK cell degranulation assay, we found mixtures of empty and full AAV8 capsids to activate expression of TNF-α, IFN-γ, and CD107a more strongly in multiple NK cell populations compared to either capsid type alone. Serum complement C3a was also induced more strongly in the presence of mixed empty and full AAV8 capsid formulations. Risk for innate immune activation suggests the importance to determine acceptable limits of empty capsids. Immunogenicity risk assessment of novel biological modalities will benefit from the aforementioned in vitro innate immune activation assays providing valuable mechanistic information.

Chronic stimulation desensitizes β2-adrenergic receptor responses in natural killer cells

Adrenergic receptors (ARs) are preferentially expressed by innate lymphocytes such as natural killer (NK) cells. Here, we study the effect of epinephrine-mediated stimulation of the β2-adrenergic receptor (β2AR) on the function of human NK cells. Epinephrine stimulation inhibited early NK cell signaling events and blocked the function of the integrin LFA-1. This reduced the adhesion of NK cells to ICAM-1, explaining how NK cells are mobilized into the peripheral blood upon epinephrine release during acute stress or exercise. Additionally, epinephrine stimulation transiently reduced NK cell degranulation, serial killing, and cytokine production and affected metabolic changes upon NK cell activation via the cAMP-protein kinase A (PKA) pathway. Repeated exposure to β2AR agonists resulted in the desensitization of the β2AR via a PKA feedback loop-initiated G-protein switch. Therefore, acute epinephrine stimulation of chronically β2AR stimulated NK cells no longer resulted in inhibited signaling and reduced LFA-1 activity. Sustained stimulation by long-acting β2-agonists (LABA) not only inhibited NK cell functions but also resulted in desensitization of the β2AR. However, peripheral NK cells from LABA-treated asthma patients still reacted unchanged to epinephrine stimulation, demonstrating that local LABA administration does not result in detectable systemic effects on NK cells.

Downregulating human leucocyte antigens on mesenchymal stromal cells by epigenetically repressing a β2-microglobulin super-enhancer

Immune rejection caused by mismatches in human leucocyte antigens (HLAs) remains a major obstacle to the success of allogeneic cell therapies. Current strategies for the generation of 'universal' immune-compatible cells, particularly the editing of HLA class I (HLA-I) genes or the modulation of proteins that inhibit natural killer cells, often result in genomic instability or cellular cytotoxicity. Here we show that a β2-microglobulin super-enhancer (B2M-SE) that is responsive to interferon-γ is a critical regulator of the expression of HLA-I on mesenchymal stromal cells (MSCs). Targeted epigenetic repression of B2M-SE in MSCs reduced the surface expression of HLA-I below the threshold required to activate allogenic T cells while maintaining levels sufficient to evade cytotoxicity mediated by natural killer cells. In a humanized mouse model, the epigenetically edited MSCs demonstrated improved survival by evading the immune system, allowing them to exert enhanced therapeutic effects on LPS-induced acute lung injury. Targeted epigenetic repression of B2M-SE may facilitate the development of off-the-shelf cell sources for allogeneic cell therapy.

C/EBPβ-dependent autophagy inhibition hinders NK cell function in cancer

NK cells are endowed with tumor killing ability, nevertheless most cancers impair NK cell functionality, and cell-based therapies have limited efficacy in solid tumors. How cancers render NK cell dysfunctional is unclear, and overcoming resistance is an important immune-therapeutic aim. Here, we identify autophagy as a central regulator of NK cell anti-tumor function. Analysis of differentially expressed genes in tumor-infiltrating versus non-tumor NK cells from our previously published scRNA-seq data of advanced human prostate cancer shows deregulation of the autophagic pathway in tumor-infiltrating NK cells. We confirm this by flow cytometry in patients and in diverse cancer models in mice. We further demonstrate that exposure of NK cells to cancer deregulates the autophagic process, decreases mitochondrial polarization and impairs effector functions. Mechanistically, CCAAT enhancer binding protein beta (C/EBPβ), downstream of CXCL12-CXCR4 interaction, acts as regulator of NK cell metabolism. Accordingly, inhibition of CXCR4 and C/EBPβ restores NK cell fitness. Finally, genetic and pharmacological activation of autophagy improves NK cell effector and cytotoxic functions, which enables tumour control by NK and CAR-NK cells. In conclusion, our study identifies autophagy as an intracellular checkpoint in NK cells and introduces autophagy regulation as an approach to strengthen NK-cell-based immunotherapies.

Integrated single-cell transcriptome and TCR profiles of hepatocellular carcinoma highlight the convergence on interferon signaling during immunotherapy

BACKGROUND

Despite the success of immune checkpoint inhibitor (ICI)-based combination therapies in hepatocellular carcinoma (HCC), its effectiveness remains confined to a subset of patients. The development of reliable, predictive markers is important for accurate patient stratification and further mechanistic understanding of therapy response.

METHODS

We comprehensively analyzed paired single-cell RNA transcriptome and T-cell repertoire profiles from 14 HCC ascites samples, collected from 7 patients before and after treatment with the combination of sintilimab (anti-PD-1) and bevacizumab (anti-VEGF).

RESULTS

We identify a widespread convergence on interferon (IFN) signaling across various immune cell lineages in treatment-responsive patients with HCC, indicating a common transcriptional state transition in the immune microenvironment linked to immunotherapy response in HCC. Strong IFN signaling marks CD8+ T cells with larger clonal expansion and enhanced cytotoxicity, macrophages toward M1-like polarization and strong T-cell recruitment ability, dendritic cells with increased antigen presentation capacity, as well as highly cytotoxic natural killer cells and activated B cells. By translating our finding to cohorts of patients with HCC, we demonstrate the specificity of IFN-signaling in the prognosis of patients with HCC and its ability to predict immunotherapy response.

CONCLUSIONS

This study provides a unique single-cell resource with clonal and longitudinal resolution during ICI therapy and reveals IFN signaling as a biomarker of immunotherapy response in HCC, suggesting a beneficial effect by combining IFN inducers with ICIs for patients with HCC.

Mechanisms by which obesity regulates inflammation and anti-tumor immunity in cancer

Obesity is associated with an increased risk for 13 different cancers. The increased risk for cancer in obesity is mediated by obesity-associated changes in the immune system. Obesity has distinct effects on different types of inflammation that are tied to tumorigenesis. For example, obesity promotes chronic inflammation in adipose tissue that is tumor-promoting in peripheral tissues. Conversely, obesity inhibits acute inflammation that rejects tumors. Obesity therefore promotes cancer by differentially regulating chronic versus acute inflammation. Given that obesity is chronic, the initial inflammation in adipose tissue will lead to systemic inflammation that could induce compensatory anti-inflammatory reactions in peripheral tissues to suppress chronic inflammation. The overall effect of obesity in peripheral tissues is therefore dependent on the duration and severity of obesity. Adipose tissue is a complex tissue that is composed of many cell types in addition to adipocytes. Further, adipose tissue cellularity is different at different anatomical sites throughout the body. Consequently, the sensitivity of adipose tissue to obesity is dependent on the anatomical location of the adipose depot. For example, obesity induces more inflammation in visceral than subcutaneous adipose tissue. Based on these studies, the mechanisms by which obesity promotes tumorigenesis are multifactorial and immune cell type-specific. The objective of our paper is to discuss the cellular mechanisms by which obesity promotes tumorigenesis by regulating distinct types of inflammation in adipose tissue and the tumor microenvironment.

The antitumor effect of extracellular vesicles derived from cytokine-activated CD8+ T cells

Extracellular vesicles (EVs) are nano-sized membrane particles secreted by various cell types that are involved in many important cellular processes. Recently, EVs originating from immune cells, such as dendritic cells, chimeric antigen receptor T cells, and natural killer cells, have attracted much attention because of their known direct and indirect antitumor activity. Here, we report the EVs released by cytokine-activated CD8+ T (caCD8) cells and its cytotoxicity against cancer cells. CaCD8 cells can release EVs following stimulation of CD8+ T cells with an anti-CD3 antibody and a cytokine cocktail ex vivo. The isolated vesicles have typical EV characteristics, such as an oval shape and a size distribution between 30 and 200 nm, as well as CD81 expression. Notably, caCD8-EVs displayed cytotoxicity against various cancer cells in vitro. Furthermore, mechanism analysis demonstrates that caCD8-EVs not only contain typical cytotoxic proteins (i.e. granzyme B and perforin), but also significantly enrich interferon γ (IFNγ) compared with caCD8 cells. EV-derived IFNγ participates in EV-induced apoptosis in cancer cells. Therefore, our data reveal antitumor effects of EVs secreted from caCD8 cells and the potential role of the EV-derived IFNγ.

A review and statistical analysis to identify and describe relationships between CQAs and CPPs of natural killer cell expansion processes

Natural killer (NK) cells make only a small fraction of immune cells in the human body, however, play a pivotal role in the fight against cancer by the immune system. They are capable of eliminating abnormal cells via several direct or indirect cytotoxicity pathways in a self-regulating manner, which makes them a favorable choice as a cellular therapy against cancer. Additionally, allogeneic NK cells, unlike other lymphocytes, do not or only minimally cause graft-versus-host diseases opening the door for an off-the-shelf therapy. However, to date, the production of NK cells faces several difficulties, especially because the critical process parameters (CPPs) influencing the critical quality attributes (CQAs) are difficult to identify or correlate. There are numerous different cultivation platforms available, all with own characteristics, benefits and disadvantages that add further difficulty to define CPPs and relate them to CQAs. Our goal in this contribution was to summarize the current knowledge about NK cell expansion CPPs and CQAs, therefore we analyzed the available literature of both dynamic and static culture format experiments in a systematic manner. We present a list of the identified CQAs and CPPs and discuss the role of each CPP in the regulation of the CQAs. Furthermore, we could identify potential relationships between certain CPPs and CQAs. The findings based on this systematic literature research can be the foundation for meaningful experiments leading to better process understanding and eventually control.

Natural Killer Cells in Cancers of Respiratory System and Their Applications in Therapeutic Approaches

BACKGROUND

Cancer is still regarded as a major worldwide health issue due to its high health and socioeconomic burden. Currently, lung cancer is the most common cause of cancer-related fatalities globally. Additionally, mesotheliomas and other cancers of the respiratory system, including those of the trachea, larynx, and bronchi, are also posing a significant health threat. Natural killer (NK) cells are lymphocytes of the innate immune system involved in response against cancer.

OBJECTIVE

This review discussed recent findings in the context of NK cell activity in the immune surveillance of respiratory system cancers and NK cell-based treatments to combat those malignancies.

RESULTS

The presence of natural killer cells in the tumor microenvironment is shown to be associated with a higher survival rate in patients with various malignancies. However, cancerous cells benefit from several mechanisms to evade natural killer cell-mediated cytotoxicity, including reduced major histocompatibility complex I expression, shedding of ligands, upregulation of inhibitory receptors, and release of soluble factors. Using NK cells to design therapeutic approaches may enhance antitumor immunity and improve clinical outcomes. Clinical trials investigating the use of natural killer cells in combination with cytokine stimulation or immune checkpoint inhibitors have exhibited promising results in various respiratory system malignancies.

CONCLUSION

Respiratory system cancers present significant health challenges worldwide, and while NK cells play a crucial role in tumor surveillance, tumors often evade NK cell responses through various mechanisms. Advances in NK cell-based therapies, including CAR-NK cells, immune checkpoint inhibitors, and cytokine stimulation, have shown promising outcomes in tackling these tactics. However, challenges such as the immunosuppressive tumor microenvironment persist. Ongoing research is crucial to improve NK cell therapies by targeting autophagy, modulating miRNAs, and developing combinatorial approaches to enhance treatment efficacy for respiratory cancers.

CD56-targeted in vivo genetic engineering of natural killer cells mediates immunotherapy for acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy that starts from bone marrow and spreads to other organs. At the time of diagnosis, both innate and defective natural killer (NK) cells are present in AML patients. The dysfunction of the NK cells is due to the absence of NK cell receptors such as NKG2D on tumor cells that help with tumor immune escape, and also the polycomb protein, EzH2, which plays an important role in the commitment and differentiation of NK cells. The inhibition of EzH2 activates NK cells towards enhanced lytic activity. However, the adoptive transfer of NK cells for cancer treatment is still under scrutiny due to limitations like production cost, vein-to-vein time, and complicated experimental procedures. In order to circumvent these issues, here, in vivo CD56+ NK cell genetic engineering is hypothesized through the CD56-directed delivery of the pSMP-EzH2 shRNA plasmid encapsulated in chitosan nanoparticles (pEzH2@CSNPs@CD56). The pSMP-EzH2 shRNA plasmid was encapsulated in chitosan nanoparticles followed by CD56 antibody conjugation through EDC-NHS chemistry. CD56 antibody-conjugated nanoparticles selectively target CD56+ NK cells and downregulate EzH2 expression in CD56+ NK cells of human PBMCs. The in vitro CD56+ CD3- NK cells were enriched and stably suppressed EzH2 expression to prepare adoptive CD56+ CD3- NK (EzH2-) cells for anti-AML immunotherapy. The in vitro NK (EzH2-) cells and pEzH2@CSNPs@CD56 reduced splenomegaly while immunophenotyping revealed in vivo downregulation of the c-Kit+ leukemia stem cell population along with upregulation of the differentiation markers CD11b and Gr-1 in the peripheral blood and bone marrow of AML1-ETO9a-induced xenograft nude mice. CD56+CD3- and CD56+CD38+ cell populations were significantly increased in the peripheral blood and bone marrow, which indicated NK cell-mediated AML cell killing took place suggesting that use of pEzH2@CSNPs@CD56 is a safe and viable strategy for NK cell-mediated anti-AML immunotherapy.

Understanding dental pulp inflammation: from signaling to structure

The pulp is a unique tissue within each tooth that is susceptible to painful inflammation, known as pulpitis, triggered by microbial invasion from carious lesions or trauma that affect many individuals. The host response involves complex immunological processes for pathogen defense and dentin apposition at the site of infection. The interplay of signaling between the immune and non-immune cells via cytokines, chemokines, neuropeptides, proteases, and reactive nitrogen and oxygen species leads to tissue reactions and structural changes in the pulp that escalate beyond a certain threshold to irreversible tissue damage. If left untreated, the inflammation, which is initially localized, can progress to pulpal necrosis, requiring root canal treatment and adversely affecting the prognosis of the tooth. To preserve pulp vitality and dental health, a deeper understanding of the molecular and cellular mechanisms of pulpitis is imperative. In particular, elucidating the links between signaling pathways, clinical symptoms, and spatiotemporal spread is essential to develop novel therapeutic strategies and push the boundaries of vital pulp therapy.

Longitudinal transcriptional changes reveal genes from the natural killer cell-mediated cytotoxicity pathway as critical players underlying COVID-19 progression

Patients present a wide range of clinical severities in response severe acute respiratory syndrome coronavirus 2 infection, but the underlying molecular and cellular reasons why clinical outcomes vary so greatly within the population remains unknown. Here, we report that negative clinical outcomes in severely ill patients were associated with divergent RNA transcriptome profiles in peripheral immune cells compared with mild cases during the first weeks after disease onset. Protein-protein interaction analysis indicated that early-responding cytotoxic natural killer cells were associated with an effective clearance of the virus and a less severe outcome. This innate immune response was associated with the activation of select cytokine-cytokine receptor pathways and robust Th1/Th2 cell differentiation profiles. In contrast, severely ill patients exhibited a dysregulation between innate and adaptive responses affiliated with divergent Th1/Th2 profiles and negative outcomes. This knowledge forms the basis of clinical triage that may be used to preemptively detect high-risk patients before life-threatening outcomes ensue.

Polysaccharide extract of Spirulina sp. increases effector immune-cell killing activities against cholangiocarcinoma

Cyanobacteria and algae serving as promising food supplements have recently garnered attention for their emerging potential in anti-cancer activity. Cholangiocarcinoma (CCA) or bile duct cancer is one of the top-leading cancers affecting people, particularly in Asian continent. With patients exhibiting no or minimal symptoms in the early stages, advanced CCA is often diagnosed, and primary treatments such as surgery may not be suitable. Discovery of natural bioactive compounds for cancer treatments have, thus, attracted attention as one of the effective means to combat CCA or to supplement primary treatments. In this work, ethanolic and polysaccharide extracts of cyanobacteria and algae were tested for their cytotoxicity against 2 CCA cell lines (KKU055 and KKU213A). The ethanolic extracts from Leptolyngbya sp. and Chlorella sp. demonstrated growth inhibition of both CCA cell lines, with IC50 values of 0.658 mg/mL and 0.687 mg/mL for KKU055, and 0.656 mg/mL and 0.450 mg/mL for KKU213A. In contrast, only the polysaccharide extracts from Sargassum spp. exhibited a remarkable cytotoxic effect, while the polysaccharide extract from Spirulina sp. showed slight effect only at a higher concentration (2 mg/mL). All tested extracts were further investigated for improving immune cell killing ability and showed that Spirulina sp. polysaccharide extract was able to improve the immune cell killing ability. This extract was then investigated for its effects on the immune cell population, which demonstrated to have positive impact on NK cell population. To further explore the potential use, synergistic effect of Spirulina sp. polysaccharide extract with an already-in-use chemotherapeutic drug, gemcitabine, on immune cell cytotoxicity was investigated. The results showed that the immune cell cytotoxicity was enhanced in the co-treatment compared to the use of each treatment separately. The most apparent difference was observed in KKU055 cells where % living cells were reduced from 78.96% (immune cell alone) to 20.93% when the combined gemcitabine and Spirulina sp. extracts were used.

Integrated temporal transcriptional and epigenetic single-cell analysis reveals the intrarenal immune characteristics in an early-stage model of IgA nephropathy during its acute injury

Rationale

Kidney inflammation plays a crucial role in the pathogenesis of IgA nephropathy (IgAN), yet the specific phenotypes of immune cells involved in disease progression remain incompletely understood. Utilizing joint profiling through longitudinal single-cell RNA-sequencing (scRNAseq) and single-cell assay for transposase-accessible chromatin sequencing (scATACseq) can provide a comprehensive framework for elucidating the development of cell subset diversity and how chromatin accessibility regulates transcription.

Objective

We aimed to characterize the dynamic immune cellular landscape at a high resolution in an early IgAN mouse model with acute kidney injury (AKI).

Methods and results

A murine model was utilized to mimic 3 immunological states -"immune stability (IS), immune activation (IA) and immune remission (IR)" in early human IgAN-associated glomerulopathy during AKI, achieved through lipopolysaccharide (LPS) injection. Urinary albumin to creatinine ratio (UACR) was measured to further validate the exacerbation and resolution of kidney inflammation during this course. Paired scRNAseq and scATACseq analysis was performed on CD45+ immune cells isolated from kidney tissues obtained from CTRL (healthy vehicle), IS, IA and IR (4 or 5 mice each). The analyses revealed 7 major cell types and 24 clusters based on 72304 single-cell transcriptomes, allowing for the identification and characterization of various immune cell types within each cluster. Our data offer an impartial depiction of the immunological characteristics, as the proportions of immune cell types fluctuated throughout different stages of the disease. Specifically, these analyses also revealed novel subpopulations, such as a macrophage subset (Nlrp1b Mac) with distinct epigenetic features and a unique transcription factor motif profile, potentially exerting immunoregulatory effects, as well as an early subset of Tex distinguished by their effector and cytolytic potential (CX3CR1-transTeff). Furthermore, in order to investigate the potential interaction between immune cells and renal resident cells, we conducted single-cell RNA sequencing on kidney cells obtained from a separate cohort of IS and IA mice without isolating immune cells. These findings underscored the diverse roles played by macrophages and CD8+ T cells in maintaining homeostasis of endothelial cells (ECs) under stress.

Conclusions

This study presents a comprehensive analysis of the dynamic changes in immune cell profiles in a model of IgAN, identifying key cell types and their roles and interactions. These findings significantly contribute to the understanding of the pathogenesis of IgAN and may provide potential targets for therapeutic intervention.

Investigating nano-sized tumor-derived extracellular vesicles in enhancing anti-PD-1 immunotherapy

Anti-PD1 immune checkpoint blockade (ICB) has shown promising results for treating several aggressive cancers, enhancing patient survival rates. The variability in clinical response to anti-PD1 ICB is thought to be driven by patient-specific biology and heterogeneity within the tumor microenvironment. Tumor-derived extracellular vesicles (TDEVs), nano-sized particles released from tumor cells, can modulate the tumor microenvironment, leading to immunosuppression and tumor progression. Hence, TDEVs may contribute to the variability in treatment response and play a crucial role in the failure of anti-PD1 immunotherapy. In this study, we develop a systems biology approach to interrogate the role of TDEVs on the response dynamics for anti-PD1 blockade. Our results suggest that the detection and profiling of TDEVs can help screen patients for anti-PD-1 immunotherapy. Moreover, the results in this study suggest that TDEVs and IL-12 can potentially be liquid biopsy biomarkers to profile patient response to anti-PD1 ICB and tailor patient-specific treatment protocols. Importantly, the methodology is generalizable to other types of cancer immunotherapies. Therefore, the collection of patient-specific liquid biopsy data, and the implementation of those data into the systems biology framework, may offer the opportunity to discover new biomarkers for patient drug screening and enable the continuous monitoring of patient response to treatment and adaptation of patient-specific immunotherapy treatment protocols to overcome therapeutic resistance.

Assessment of NK cytotoxicity and interactions with porcine endothelial cells by live-cell imaging in 2D static and 3D microfluidic systems

Natural Killer (NK) cells are pivotal in immune responses to viral infections, malignancies, autoimmune diseases, and transplantation. Assessment of NK cell adhesion, migration, and cytotoxicity is fundamental for in vitro studies. We propose a novel live-cell tracking method that addresses these three major aspects of NK cell function using human NK cells and primary porcine aortic endothelial cells (PAECs) in two-dimensional (2D) static assays and an in-house cylindrical 3D microfluidic system. The results showed a significant increase of NK cytotoxicity against pTNF-activated PAECs, with apoptotic cell death observed in the majority of dead cells, while no difference was observed in the conventional Delfia assay. Computed analysis of NK cell trajectories revealed distinct migratory behaviors, including trajectory length, diameter, average speed, and arrest coefficient. In 3D microfluidic experiments, NK cell attachment to pTNF-activated PAECs substantially increased, accompanied by more dead PAECs compared to control conditions. NK cell trajectories showed versatile migration in various directions and interactions with PAECs. This study uniquely demonstrates NK attachment and killing in a 3D system that mimics blood vessel conditions. Our microscope method offers sensitive single-cell level results, addressing diverse aspects of NK functions. It is adaptable for studying other immune and target cells, providing insights into various biological questions.

State of the Field: Cytotoxic Immune Cell Responses in C. neoformans and C. deneoformans Infection

Cryptococcus neoformans is an environmental pathogen that causes life-threatening disease in immunocompromised persons. The majority of immunological studies have centered on CD4+ T-cell dysfunction and associated cytokine signaling pathways, optimization of phagocytic cell function against fungal cells, and identification of robust antigens for vaccine development. However, a growing body of literature exists regarding cytotoxic cells, specifically CD8+ T-cells, Natural Killer cells, gamma/delta T-cells, NK T-cells, and Cytotoxic CD4+ T-cells, and their role in the innate and adaptive immune response during C. neoformans and C. deneoformans infection. In this review, we (1) provide a comprehensive report of data gathered from mouse and human studies on cytotoxic cell function and phenotype, (2) discuss harmonious and conflicting results on cellular responses in mice models and human infection, (3) identify gaps of knowledge in the field ripe for exploration, and (4) highlight how innovative immunological tools could enhance the study of cytotoxic cells and their potential immunomodulation during cryptococcosis.

Transcriptome-wide N6-methyladenosine modification profiling of long non-coding RNAs in patients with recurrent implantation failure

N6-methyladenosine (m6A) is involved in most biological processes and actively participates in the regulation of reproduction. According to recent research, long non-coding RNAs (lncRNAs) and their m6A modifications are involved in reproductive diseases. In the present study, using m6A-modified RNA immunoprecipitation sequencing (m6A-seq), we established the m6A methylation transcription profiles in patients with recurrent implantation failure (RIF) for the first time. There were 1443 significantly upregulated m6A peaks and 425 significantly downregulated m6A peaks in RIF. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that genes associated with differentially methylated lncRNAs are involved in the p53 signalling pathway and amino acid metabolism. The competing endogenous RNA network revealed a regulatory relationship between lncRNAs, microRNAs and messenger RNAs. We verified the m6A methylation abundances of lncRNAs by using m6A-RNA immunoprecipitation (MeRIP)-real-time polymerase chain reaction. This study lays a foundation for further exploration of the potential role of m6A modification in the pathogenesis of RIF.

Consensus, debate, and prospective on pancreatic cancer treatments

Pancreatic cancer remains one of the most aggressive solid tumors. As a systemic disease, despite the improvement of multi-modality treatment strategies, the prognosis of pancreatic cancer was not improved dramatically. For resectable or borderline resectable patients, the surgical strategy centered on improving R0 resection rate is consensus; however, the role of neoadjuvant therapy in resectable patients and the optimal neoadjuvant therapy of chemotherapy with or without radiotherapy in borderline resectable patients were debated. Postoperative adjuvant chemotherapy of gemcitabine/capecitabine or mFOLFIRINOX is recommended regardless of the margin status. Chemotherapy as the first-line treatment strategy for advanced or metastatic patients included FOLFIRINOX, gemcitabine/nab-paclitaxel, or NALIRIFOX regimens whereas 5-FU plus liposomal irinotecan was the only standard of care second-line therapy. Immunotherapy is an innovative therapy although anti-PD-1 antibody is currently the only agent approved by for MSI-H, dMMR, or TMB-high solid tumors, which represent a very small subset of pancreatic cancers. Combination strategies to increase the immunogenicity and to overcome the immunosuppressive tumor microenvironment may sensitize pancreatic cancer to immunotherapy. Targeted therapies represented by PARP and KRAS inhibitors are also under investigation, showing benefits in improving progression-free survival and objective response rate. This review discusses the current treatment modalities and highlights innovative therapies for pancreatic cancer.

Killing of xenogenous and virally infected homogenous target cells by shrimp lymphocyte-like haemocytes

Haemocytes play a crucial role in the invertebrate's immune system. In our lab, five subpopulations of shrimp haemocytes were identified in the past: hyalinocytes, granulocytes, semi-granulocytes and two subpopulations of non-phagocytic cells. In the latter two subpopulations, their characteristics such as having small cytoplasmic rims and not adhering to plastic cell-culture plates are very similar to those of mammalian lymphocytes. Therefore, they were designated lymphocyte-like haemocytes. Although little is known about their function, we hypothesize, based on their morphology, that they may have a cytotoxic activity like natural killer cells, with the ability to recognize and kill target cells. In our study, K562 cells and Sf9 cells were used as xenogenous target cells to detect the cytotoxic activity of the shrimp non-adherent lymphocyte-like haemocytes. Non-adherent haemocytes were collected and mixed with K562 cells and Sf9 cells at a 5:1 ratio and the binding activity was examined under a microscope. The binding rate of non-adherent haemocytes to K562 cells and Sf9 cells reached 6.6 % and 2.4 % after 240 min of culture, respectively. Then, the killing activity of non-adherent haemocytes was detected by an EMA staining (fluorescence microscopy), which showed 3.75 % dead K562 cells and 1.025 % dead Sf9 cells, and by Sytox® blue staining (flow cytometry), which showed 4.97 % of dead K562 cells. Next, a killing assay was developed to visualize the killing activity of shrimp non-adherent haemocytes. Non-adherent haemocytes were pre-labeled in blue (CellTracker blue) and K562/Sf9 cells in green (CFSE); dead cells were differentially stained red with ethidium bromide. The cytotoxic activity increased and reached a level of 2.59 % in K562 cells and 0.925 % in Sf9 cells at 120 min after co-culture. Furthermore, in the co-cultures of non-adherent haemocytes with K562 cells and Sf9 cells, upregulation of the gene and protein expression of the cytotoxic molecules torso-like protein and granzyme B was observed by RT-qPCR at 240 min and western blotting at 180 min. Additionally, non-adherent haemocytes were co-cultured with WSSV-inoculated shrimp ovary and lymphoid organ cells to detect the cytotoxicity to homogenous target cells. The binding activity started at 60 min in both the ovary and lymphoid organ cultures and reached at 240 min 50.62 % and 40.7 %, respectively. The killing activity was detected by EMA staining and the percentage of dead ovary and lymphoid organ cells increased respectively from 10.84 % to 6.89 % at 0 min to 13.09 % and 8.37 % at 240 min. In conclusion, we demonstrated the existence of cytotoxic activity of shrimp lymphocyte-like haemocytes against xenogenous cells from mammals and insects and against WSSV-infected homogenous shrimp cells.

The Role of Viral Infections in the Development and Progression of COPD

Chronic obstructive pulmonary disease (COPD) is a common chronic disease seen in smokers associated with poor functional status, quality of life, and morbidity and mortality from acute worsening of chronic symptoms, also called exacerbations. As a disease, the risk factors for COPD are well defined; however, there is room for innovation in identifying underlying biological processes, or "endotypes," that lead to the emergence and/or progression of COPD. Identifying endotypes allows for more thorough understanding of the disease, may reveal the means of disease prevention, and may be leveraged in novel therapeutic approaches. In this review, we discuss the interface of viral infections with both cellular and epithelial immunity as a potential endotype of interest in COPD.

Left out in the cold: Moving beyond hormonal therapy for the treatment of immunologically cold prostate cancer with CAR T cell immunotherapies

Prostate cancer is primarily hormone-dependent, and medical treatments have focused on inhibiting androgen biosynthesis or signaling through various approaches. Despite significant advances with the introduction of androgen receptor signalling inhibitors (ARSIs), patients continue to progress to castration-resistant prostate cancer (CRPC), highlighting the need for targeted therapies that extend beyond hormonal blockade. Chimeric Antigen Receptor (CAR) T cells and other engineered immune cells represent a new generation of adoptive cellular therapies. While these therapies have significantly enhanced outcomes for patients with hematological malignancies, ongoing research is exploring the broader use of CAR T therapy in solid tumors, including advanced prostate cancer. In general, CAR T cell therapies are less effective against solid cancers with the immunosuppressive tumor microenvironment hindering T cell infiltration, activation and cytotoxicity following antigen recognition. In addition, inherent tumor heterogeneity exists in patients with advanced prostate cancer that may prevent durable therapeutic responses using single-target agents. These barriers must be overcome to inform clinical trial design and improve treatment efficacy. In this review, we discuss the innovative and rationally designed strategies under investigation to improve the clinical translation of cellular immunotherapy in prostate cancer and maximise therapeutic outcomes for these patients.