Synergy Between NK Cells and Monocytes in Potentiating Cardiovascular Disease Risk in Severe COVID-19.

BACKGROUND: Evidence suggests that COVID-19 predisposes to cardiovascular diseases (CVDs). While monocytes/macrophages play a central role in the immunopathogenesis of atherosclerosis, less is known about their immunopathogenic mechanisms that lead to CVDs during COVID-19. Natural killer (NK) cells, which play an intermediary role during pathologies like atherosclerosis, are dysregulated during COVID-19. Here, we sought to investigate altered immune cells and their associations with CVD risk during severe COVID-19. METHODS: We measured plasma biomarkers of CVDs and determined phenotypes of circulating immune subsets using spectral flow cytometry. We compared these between patients with severe COVID-19 (severe, n=31), those who recovered from severe COVID-19 (recovered, n=29), and SARS-CoV-2-uninfected controls (controls, n=17). In vivo observations were supported using in vitro assays to highlight possible mechanistic links between dysregulated immune subsets and biomarkers during and after COVID-19. We performed multidimensional analyses of published single-cell transcriptome data of monocytes and NK cells during severe COVID-19 to substantiate in vivo findings. RESULTS: During severe COVID-19, we observed alterations in cardiometabolic biomarkers including oxidized-low-density lipoprotein, which showed decreased levels in severe and recovered groups. Severe patients exhibited dysregulated monocyte subsets, including increased frequencies of proinflammatory intermediate monocytes (also observed in the recovered) and decreased nonclassical monocytes. All identified NK-cell subsets in the severe COVID-19 group displayed increased expression of activation and tissue-resident markers, such as CD69. We observed significant correlations between altered immune subsets and plasma oxidized-low-density lipoprotein levels. In vitro assays revealed increased uptake of oxidized-low-density lipoprotein into monocyte-derived macrophages in the presence of NK cells activated by plasma of patients with severe COVID-19. Transcriptome analyses confirmed enriched proinflammatory responses and lipid dysregulation associated with epigenetic modifications in monocytes and NK cells during severe COVID-19. CONCLUSIONS: Our study provides new insights into the involvement of monocytes and NK cells in the increased CVD risk observed during and after COVID-19.

Single-cell transcriptomic analysis to identify endomembrane regulation of metalloproteins and motor proteins in autoimmunity.

TMEM230 promotes antigen processing, trafficking, and presentation by regulating the endomembrane system of membrane bound organelles (lysosomes, proteosomes and mitochondria) and phagosomes. Activation of the immune system requires trafficking of various cargos between the endomembrane system and cell plasma membrane. The Golgi apparatus is the hub of the endomembrane system and essential for the generation, maintenance, recycling, and trafficking of the components of the endomembrane system itself and immune system. Intracellular trafficking and secretion of immune system components depend on mitochondrial metalloproteins for ATP synthesis that powers motor protein transport of endomembrane cargo. Glycan modifying enzyme genes and motor proteins are essential for the activation of the immune system and trafficking of antigens between the endomembrane system and the plasma membrane. Recently, TMEM230 was identified as co-regulated with RNASET2 in lysosomes and with metalloproteins in various cell types and organelles, including mitochondria in autoimmune diseases. Aberrant metalloproteinase secretion by motor proteins is a major contributor to tissue remodeling of synovial membrane and joint tissue destruction in rheumatoid arthritis (RA) by promoting infiltration of blood vessels, bone erosion, and loss of cartilage by phagocytes. In this study, we identified that specific glycan processing enzymes are upregulated in certain cell types (fibroblast or endothelial cells) that function in destructive tissue remodeling in rheumatoid arthritis compared to osteoarthritis (OA). TMEM230 was identified as a regulator in the secretion of metaloproteinases and heparanase necessary tissue remodeling in OA and RA. In dendritic (DC), natural killer and T cells, TMEM230 was expressed at low or no levels in RA compared to OA. TMEM230 expression in DC likely is necessary for regulatory or helper T cells to maintain tolerance to self-antigens and prevent susceptibility to autoimmune disease. To identify how TMEM230 and the endomembrane system contribute to autoimmunity we investigated, glycan modifying enzymes, metalloproteinases and motor protein genes co-regulated with or regulated by TMEM230 in synovial tissue by analyzing published single cell transcriptomic datasets from RA patient derived synovial tissue.

HLA-E-expressing macrophage polarization and increased NKG2A/CD94 expression in adult-onset Still's disease.

We investigated the phenotypic characteristics of human leukocyte antigen (HLA)-E-expressing macrophages, NKG2A/CD94 expression in T and natural killer (NK) cells, and their interactions in patients with adult-onset Still's disease (AOSD). Peripheral blood mononuclear cells from 22 patients with AOSD and 22 healthy controls (HC) were used. Isolated monocytes were cultured first with macrophage colony-stimulating factor to differentiate into M0 macrophages and subsequently with lipopolysaccharide/interferon-γ or interleukin-4 to differentiate into M1 or M2 macrophages, respectively. HLA-E and NKG2A/CD94 expression levels were evaluated using quantitative RT-PCR and flow cytometry. HLA-E expression in M0 and M2 macrophages was significantly higher in patients with AOSD than in HC, and was positively correlated with serum C-reactive protein levels and erythrocyte sedimentation rate. NKG2A/CD94 expression in CD4 + and CD8 + T cells was significantly higher in patients with AOSD than in HC, but that in NK cells was not significantly different. In patients with AOSD, NKG2A expression in CD4 + T cells positively correlated with HLA-E expression in M0, M1, and M2 macrophages. CD94 expression in CD8 + T cells inversely correlated with HLA-E expression in M1 and M2 macrophages. NKG2A and CD94 expression in NK cells inversely correlated with HLA-E expression in M0, M1, and M2 macrophages. No significant correlation was observed between HLA-E and NKG2A/CD94 expression in HC. Increased expression of HLA-E in macrophages and NKG2A/CD94 in T cells can be observed in the inflammatory condition of AOSD. HLA-E-expressing macrophages may be associated with NKG2A/CD94 expression in T and NK cells with different correlations.

Natural killer cell-derived exosome-based cancer therapy: from biological roles to clinical significance and implications.

Natural killer (NK) cells are important immune cells in the organism and are the third major type of lymphocytes besides T cells and B cells, which play an important function in cancer therapy. In addition to retaining the tumor cell killing function of natural killer cells, natural killer cell-derived exosomes cells also have the characteristics of high safety, wide source, easy to preserve and transport. At the same time, natural killer cell-derived exosomes are easy to modify, and the engineered exosomes can be used in combination with a variety of current cancer therapies, which not only enhances the therapeutic efficacy, but also significantly reduces the side effects. Therefore, this review summarizes the source, isolation and modification strategies of natural killer cell-derived exosomes and the combined application of natural killer cell-derived engineered exosomes with other antitumor therapies, which is expected to accelerate the clinical translation process of natural killer cell-derived engineered exosomes in cancer therapy.

Blockade of the TIGIT-CD155/CD112 axis enhances functionality of NK-92 but not cytokine-induced memory-like NK cells toward CD155-expressing acute myeloid leukemia.

TIGIT is an alternative checkpoint receptor (CR) whose inhibition promotes Graft-versus-Leukemia effects of NK cells. Given the significant immune-permissiveness of NK cells circulating in acute myeloid leukemia (AML) patients, we asked whether adoptive transfer of activated NK cells would benefit from additional TIGIT-blockade. Hence, we characterized cytokine-induced memory-like (CIML)-NK cells and NK cell lines for the expression of inhibitory CRs. In addition, we analyzed the transcription of CR ligands in AML patients (CCLE and Beat AML 2.0 cohort) in silico and evaluated the efficacy of CR blockade using in vitro cytotoxicity assays, CD69, CD107a and IFN-γ expression. Alternative but not classical CRs were abundantly expressed on healthy donor NK cells and even further upregulated on CIML-NK cells. In line with our finding that CD155, one important TIGIT-ligand, is reliably expressed on AMLs, we show improved killing of CD155+-AML blasts by NK-92 but interestingly not CIML-NK cells in the presence of TIGIT-blockade. Additionally, our in silico data (n = 671) show that poor prognosis AML patients rather displayed a CD86low CD112/CD155high phenotype, whereas patients with a better outcome rather exhibited a CD86high CD112/CD155low phenotype. Collectively, our data evidence that the complex CR ligand expression profile on AML blasts may be one explanation for the intrinsic NK cell exhaustion observed in AML patients which might be overcome with adoptive NK-92 transfer in combination with TIGIT-blockade.

Dynamic Changes in the Immune Microenvironment in Tumor-Draining Lymph Nodes of a Lewis Lung Cancer Mouse Model After Microwave Ablation.

Purpose: Microwave ablation (MWA) is a minimally invasive technique for treating lung cancer. It can induce immune response; however, its effect on the immune microenvironment in tumor-draining lymph nodes (TdLN) is not well understood. This study aims to identify changes in the immune microenvironment in TdLN following MWA in a Lewis lung cancer (LLC) mouse model. Methods: LLC mouse model was established and followed by MWA. TdLN were collected at various time points, including pre-MWA and days 1, 2, 4, and 8 post-MWA. Flow cytometry was used to determine the frequencies of CD4+ T cells, CD8+ T cells, regulatory T (Treg) cells, natural killer (NK) cells, dendritic cells (DCs) and other immune cells in the TdLN. Certain cytokines were also detected. Results: Compared with pre-MWA, the frequency of CD4+ T cells significantly increased from day 1 to day 8 post-MWA. The frequency of CD8+ T cells decreased significantly on days 2 and 4, but no significant changes occurred on days 1 and 8. Significant decreases in the frequencies of Treg cells and Klrg1+ Treg cells were observed from day 1 to day 4. On days 4 and 8, there was a significant increase in the frequency of NK cells. The frequency of resident cDC2 significantly increased on day 4, whereas CD11b+ migratory cDCs increased on day 1. Additionally, on day 4, a notable rise was observed in the frequency of NK cells secreting IFN-γ, while on day 8, there was a significant increase in the frequency of CD8+ T cells secreting both IFN-γ and TNF-α. Conclusion: MWA of lung cancer can alter the immune microenvironment in the TdLN, triggering immune responses. These changes are particularly evident and intricate within the initial 4 days post-MWA. Treatment combined with MWA within a certain period may significantly enhance anti-tumor immunity.

Genetic ablation of adhesion ligands mitigates rejection of allogeneic cellular immunotherapies.

Allogeneic cellular immunotherapies hold promise for broad clinical implementation but face limitations due to potential rejection of donor cells by the host immune system. Silencing of beta-2 microglobulin (B2M) expression is commonly employed to evade T cell-mediated rejection by the host, although the absence of B2M is expected to trigger missing-self responses by host natural killer (NK) cells. Here, we demonstrate that genetic deletion of the adhesion ligands CD54 and CD58 in B2M-deficient chimeric antigen receptor (CAR) T cells and multi-edited induced pluripotent stem cell (iPSC)-derived CAR NK cells reduces their susceptibility to rejection by host NK cells in vitro and in vivo. The absence of adhesion ligands limits rejection in a unidirectional manner in B2M-deficient and B2M-sufficient settings without affecting the antitumor functionality of the engineered donor cells. Thus, these data suggest that genetic ablation of adhesion ligands effectively alleviates rejection by host immune cells, facilitating the implementation of universal immunotherapy.

Infectious mononucleosis complicated by transitory Epstein-Barr virus infection of T and natural killer cells.

Epstein-Barr virus (EBV) typically infects B cells in infectious mononucleosis (IM), but a rare case shows EBV infection in T cells. Seven cases of lymphoproliferative disorder caused by EBV-positive cytotoxic T/natural killer (NK) cell proliferation in the lymph nodes, termed IM with transient EBV infection of T and NK cells (EBV + T/NK cells in IM), are reported here. The purpose of the study is to describe clinicopathological features of EBV + T/natural killer (NK) cells in IM of the lymph node. We retrospectively analysed seven cases of Chinese children and young people adults with EBV + T/NK cells in IM. We used morphological observation, immunohistochemical staining, EB virus in situ hybridisation detection, and analysis of T-cell receptor gene rearrangement. The patients were healthy prior to illness, experiencing sudden onset occurring in all the patients, with high fever as the first symptom, followed by lymphadenopathy and hepatosplenomegaly. Diagnosis occurred < 1.5 months of symptom onset. Most lymphocytes in lesions expressed CD3 and Granzyme B or TIA-1 and lacked CD5. CD56 was expressed in numerous cells in 5 of the 7 cases. EBV-encoded RNA (EBER) was detected in medium-to-large-sized cells (50-100 cells per cell/high-power field). T-cell receptor (TCR) gene rearrangement was seen in six cases, with monoclonal rearrangement in four cases. Treatment was conservative treatment but not chemotherapy. Four received anti-HLH therapy and others anti-inflammatory treatment. All patients survived with relapse after long-term clinical observation and follow-up. EBV + T/NK cells in IM can elicit malignant features that mimic T/NK-cell lymphoma pathologically and benign features mimicking IM clinically. These findings indicate that EBV + T/NK cells in IM could serve as valuable diagnosis. Additional clinical information, including age of onset (children and young people), nature of onset (sudden), disease course (short), symptoms (systemic), EBV infection status (acute), and lymph node involvement, is crucial for accurate diagnosis and prognostic evaluation.

A replication study of sHLA-E influence on schizophrenia and bipolar disorder.

OBJECTIVES: Schizophrenia (SZ) and bipolar disorders (BP) are chronic and severe neuropsychiatric diseases. These disorders are tightly related to immune deregulations. In the current study, we intended to replicate the previously reported involvement of the soluble HLA-E isoforms (sHLA-E) in the risk of developing the two conditions along with disease severity in a Tunisian population group. PATIENTS AND METHODS: One hundred and twenty-four patients with schizophrenia and 121 with bipolar disorder meeting the DSM-IV criteria along 111 healthy controls were included in this present case-control study. The soluble HLA-E isoforms circulating levels were measured using the ELISA method. The statistical analyses were performed using Kruskal-Wallis and Wilcoxon rank sum tests by R software and GraphPad prism 9. RESULTS: We found that the sHLA-E circulating levels were significantly higher in BP patients as compared to healthy controls (P<0.0001) and that such increases were mainly observed in patients during an acute phase of their disease (P<0.0001). In SZ patients, while we failed to observe an association with the levels of sHLA-E in the entire SZ sample, we found that high sHLA-E levels characterized stabilized patients in comparison with those during an acute episode (P=0.022). Finally, we did not observe any association between sHLA-E circulating levels and symptoms assessed by the classical clinical scales either in BP or SZ patients. CONCLUSION: Overall, the present findings replicate in a Tunisian population group the previously demonstrated implication of sHLA-E circulating levels in the risk of developing BP or SZ in a French patient cohort. Such replication allows to consider HLA-E as a potent and true inflammatory marker in the context of the two disorders.

Alginate-gelatine hydrogel microspheres protect NK cell proliferation and cytotoxicity under hypoxic conditions.

AIMS: This study aimed to encapsulate natural killer (NK) cells in a hydrogel to sustain their function within the hypoxic tumour microenvironments. METHODS: An alginate-gelatine hydrogel was generated via electrospray technology. Hydrogel biocompatibility was assessed through cell counting kit-8 and Live/Dead assays to ascertain cell. Moreover, we analysed lactate dehydrogenase assays to evaluate the cytotoxicity against tumours and utilised RT-qPCR to analyse cytokine gene level. RESULTS: Alginate and gelatine formed hydrogels with diameters ranging from 489.2 ± 23.0 µm, and the encapsulation efficiency was 34.07 ± 1.76%. Encapsulated NK cells exhibited robust proliferation and tumour-killing capabilities under normoxia and hypoxia. Furthermore, encapsulation provided a protective shield against cell viability under hypoxia. Importantly, tumour-killing cytotoxicity through cytokines upregulation such as granzyme B and interferon-gamma was preserved under hypoxia. CONCLUSION: The encapsulation of NK cells not only safeguards their viability but also reinforces anticancer capacity, countering the inhibition of activation induced by hypoxia.

Making a Monkey out of Human Immunodeficiency Virus/Simian Immunodeficiency Virus Pathogenesis: Immune Cell Depletion Experiments as a Tool to Understand the Immune Correlates of Protection and Pathogenicity in HIV Infection.

Understanding the underlying mechanisms of HIV pathogenesis is critical for designing successful HIV vaccines and cure strategies. However, achieving this goal is complicated by the virus's direct interactions with immune cells, the induction of persistent reservoirs in the immune system cells, and multiple strategies developed by the virus for immune evasion. Meanwhile, HIV and SIV infections induce a pandysfunction of the immune cell populations, making it difficult to untangle the various concurrent mechanisms of HIV pathogenesis. Over the years, one of the most successful approaches for dissecting the immune correlates of protection in HIV/SIV infection has been the in vivo depletion of various immune cell populations and assessment of the impact of these depletions on the outcome of infection in non-human primate models. Here, we present a detailed analysis of the strategies and results of manipulating SIV pathogenesis through in vivo depletions of key immune cells populations. Although each of these methods has its limitations, they have all contributed to our understanding of key pathogenic pathways in HIV/SIV infection.

Exploring the Potential of Natural Killer Cell-Based Immunotherapy in Targeting High-Grade Serous Ovarian Carcinomas.

High-grade serous ovarian cancers (HGSOCs) likely consist of poorly differentiated stem-like cells (PDSLCs) and differentiated tumor cells. Conventional therapeutics are incapable of completely eradicating PDSLCs, contributing to disease progression and tumor relapse. Primary NK cells are known to effectively lyse PDSLCs, but they exhibit low or minimal cytotoxic potential against well-differentiated tumors. We have introduced and discussed the characteristics of super-charged NK (sNK) cells in this review. sNK cells, in comparison to primary NK cells, exhibit a significantly higher capability for the direct killing of both PDSLCs and well-differentiated tumors. In addition, sNK cells secrete significantly higher levels of cytokines, especially those known to induce the differentiation of tumors. In addition, we propose that a combination of sNK and chemotherapy could be one of the most effective strategies to eliminate the heterogeneous population of ovarian tumors; sNK cells can lyse both PDSLCs and well-differentiated tumors, induce the differentiation of PDSLCs, and could be used in combination with chemotherapy to target both well-differentiated and NK-induced differentiated tumors.

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.

Increased CD56 expression after photodynamic therapy indicates an increased natural killer cell count following early photodynamic therapy for cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is the second most common type of skin cancer. Photodynamic therapy (PDT) is a promising therapeutic method for managing cSCC due to its proven ability to target specific areas over time and its low risk of side effects. PDT may cause tissue damage and vascular shutdown, and may regulate local immunological responses. The present study aimed to investigate and compare the early lymphocyte modifications before and after PDT for SCC. A total of 10 patients with SCC were identified by pathological investigation. Initially, all wounds were treated with 20% aminolevulinic acid (ALA)-PDT as the initial stage in the therapeutic procedure. The wounds were treated by exposing them to red LED light with a wavelength of 635 nm, an energy density of 100 J/cm2 and an intensity of 80 mW/cm2. The tumor tissue was surgically removed 24 h later, and another round of PDT therapy was administered. Immunohistochemistry for CD3 and CD56 was conducted on the wound tissue post-surgery. If the wound showed granulation, necrosis or secretion, debridement was added to the therapy. All patients were monitored for 0.6-1.0 year post-treatment. ALA-PDT combination surgery fully controlled the tumor tissue in all 10 patients. The immunohistochemical analysis of the wound tissues showed that the expression of CD56 increased, while the expression of CD3 was not different after photodynamic therapy. These results also indirectly indicated that the overall count of NK cells in the 10 patients increased, nevertheless, there was no alteration in the T lymphocyte count. In conclusion, the ALA-PDT combination surgical therapy for cSCC demonstrates favorable results. An increase in CD56 expression may be a mechanism for the effective treatment of cSCC with PDT.

Innate and adaptive immune responses that control lymph-borne viruses in the draining lymph node.

The interstitial fluids in tissues are constantly drained into the lymph nodes (LNs) as lymph through afferent lymphatic vessels and from LNs into the blood through efferent lymphatics. LNs are strategically positioned and have the appropriate cellular composition to serve as sites of adaptive immune initiation against invading pathogens. However, for lymph-borne viruses, which disseminate from the entry site to other tissues through the lymphatic system, immune cells in the draining LN (dLN) also play critical roles in curbing systemic viral dissemination during primary and secondary infections. Lymph-borne viruses in tissues can be transported to dLNs as free virions in the lymph or within infected cells. Regardless of the entry mechanism, infected myeloid antigen-presenting cells, including various subtypes of dendritic cells, inflammatory monocytes, and macrophages, play a critical role in initiating the innate immune response within the dLN. This innate immune response involves cellular crosstalk between infected and bystander innate immune cells that ultimately produce type I interferons (IFN-Is) and other cytokines and recruit inflammatory monocytes and natural killer (NK) cells. IFN-I and NK cell cytotoxicity can restrict systemic viral spread during primary infections and prevent serious disease. Additionally, the memory CD8+ T-cells that reside or rapidly migrate to the dLN can contribute to disease prevention during secondary viral infections. This review explores the intricate innate immune responses orchestrated within dLNs that contain primary viral infections and the role of memory CD8+ T-cells following secondary infection or CD8+ T-cell vaccination.

Lung Cancer Organoid System to Evaluate the Cytotoxicity of Natural Killer Cells.

Natural killer (NK) cells are gaining growing attention due to their promise for immunotherapy. A fast and accurate system is needed to test NK cell biology and their therapeutic application. Here, we report a lung cancer organoid-based system to evaluate NK cells' cytotoxicity. We first established the lung cancer organoids on top of Matrigel, which allows the co-culture with NK cells. When co-cultured, NK cells moved close to and inside the lung cancer organoids. When we analyzed by flow cytometry, co-culture of NK cells induced a significantly higher ratio of cell death of lung cancer organoids, suggesting that lung cancer organoids can be employed to test the cytotoxicity of NK cells. Finally, the pretreatment of NK cells with A83-01, a TGFß inhibitor, significantly enhanced the cell death of lung cancer organoids by NK cells, indicating that lung cancer organoid-based system faithfully recapitulates cell line-based system in evaluating the in vitro cytotoxicity of NK cells. These data represent that cancer organoid-based NK cell co-culture system is a reliable platform for studying NK cell biology and evaluating their cytotoxicity for screening for NK cell immunotherapy.

Acute Ascaris infection impairs the effector functions of natural killer cells in single and Salmonella co-infected pigs.

Natural killer (NK) cells play a key role in defense against Salmonella infections during the early phase of infection. Our previous work showed that the excretory/secretory products of Ascaris suum repressed NK activity in vitro. Here, we asked if NK cell functionality was influenced in domestic pigs during coinfection with Ascaris and Salmonella enterica serotype Typhimurium. Ascaris coinfection completely abolished the IL-12 and IL-18 driven elevation of IFN-γ production seen in CD16 + CD8α + perforin + NK cells of Salmonella single-infected pigs. Furthermore, Ascaris coinfection prohibited the Salmonella-driven rise in NK perforin levels and CD107a surface expression. In line with impaired effector functions, NK cells from Ascaris-single and coinfected pigs displayed elevated expression of the inhibitory KLRA1 and NKG2A receptors genes, contrasting with the higher expression of the activating NKp46 and NKp30 receptors in NK cells during Salmonella single infection. These differences were accompanied by the highly significant upregulation of T-bet protein expression in NK cells from Ascaris-single and Ascaris/Salmonella coinfected pigs. Together, our data strongly indicate a profound repression of NK functionality by an Ascaris infection which may hinder infected individuals from adequately responding to a concurrent bacterial infection.

Near-Infrared Light-Activatable DNA Tentacles for Efficient Inhibition of Tumor Metastasis by Bio-Orthogonal Cell Assembly.

Tumor metastasis remains a major challenge in cancer management. Among various treatment strategies, immune cell-based cancer therapy holds a great potential for inhibiting metastasis. However, its wide application in cancer therapy is restricted by complex preparations, as well as inadequate homing and controllability. Herein, we present a groundbreaking approach for bioorthogonally manipulating tumor-NK (natural killer) cell assembly to inhibit tumor metastasis. Multiple dibenzocyclootyne (DBCO) groups decorated long single-stranded DNA were tail-modified on core-shell upconversion nanoparticles (CSUCNPs) and condensed by photosensitive chemical linker (PC-Linker) DNA to shield most of the DBCO groups. On the one hand, the light-triggered DNA scaffolds formed a cross-linked network by click chemistry, effectively impeding tumor cell migration. On the other hand, the efficient cellular assembly facilitated the effective communication between tumor cells and NK-92 cells, leading to enhanced immune response against tumors and further suppression of tumor metastasis. These features make our strategy highly applicable to a wide range of metastatic cancers.

Leveraging Integrated RNA Sequencing to Decipher Adrenomedullin's Protective Mechanisms in Experimental Bronchopulmonary Dysplasia.

Bronchopulmonary dysplasia (BPD) is a chronic lung disease commonly affecting premature infants, with limited therapeutic options and increased long-term consequences. Adrenomedullin (Adm), a proangiogenic peptide hormone, has been found to protect rodents against experimental BPD. This study aims to elucidate the molecular and cellular mechanisms through which Adm influences BPD pathogenesis using a lipopolysaccharide (LPS)-induced model of experimental BPD in mice. Bulk RNA sequencing of Adm-sufficient (wild-type or Adm+/+) and Adm-haplodeficient (Adm+/-) mice lungs, integrated with single-cell RNA sequencing data, revealed distinct gene expression patterns and cell type alterations associated with Adm deficiency and LPS exposure. Notably, computational integration with cell atlas data revealed that Adm-haplodeficient mouse lungs exhibited gene expression signatures characteristic of increased inflammation, natural killer (NK) cell frequency, and decreased endothelial cell and type II pneumocyte frequency. Furthermore, in silico human BPD patient data analysis supported our cell type frequency finding, highlighting elevated NK cells in BPD infants. These results underscore the protective role of Adm in experimental BPD and emphasize that it is a potential therapeutic target for BPD infants with an inflammatory phenotype.

An Improved Two-Shot Tracking Algorithm for Dynamics Analysis of Natural Killer Cells in Tumor Contexts.

Natural killer cells (NKCs) are non-specific immune lymphocytes with diverse morphologies. Their broad killing effect on cancer cells has led to increased attention towards activating NKCs for anticancer immunotherapy. Consequently, understanding the motion characteristics of NKCs under different morphologies and modeling their collective dynamics under cancer cells has become crucial. However, tracking small NKCs in complex backgrounds poses significant challenges, and conventional industrial tracking algorithms often perform poorly on NKC tracking datasets. There remains a scarcity of research on NKC dynamics. In this paper, we utilize deep learning techniques to analyze the morphology of NKCs and their key points. After analyzing the shortcomings of common industrial multi-object tracking algorithms like DeepSORT in tracking natural killer cells, we propose Distance Cascade Matching and the Re-Search method to improve upon existing algorithms, yielding promising results. Through processing and tracking over 5000 frames of images, encompassing approximately 300,000 cells, we preliminarily explore the impact of NKCs' cell morphology, temperature, and cancer cell environment on NKCs' motion, along with conducting basic modeling. The main conclusions of this study are as follows: polarized cells are more likely to move along their polarization direction and exhibit stronger activity, and the maintenance of polarization makes them more likely to approach cancer cells; under equilibrium, NK cells display a Boltzmann distribution on the cancer cell surface.