Search Results (1,520)

Klebsiella pneumoniae (K. pneumoniae), a kind of zoonotic bacteria, is among the most common antibiotic-resistant pathogens, and it causes nosocomial infections that pose a threat to public health. In this study, the roles of synthetic bovine neutrophil β-defensin-5 (B5) in regulating inflammatory response and metabolic response against multidrug-resistant K. pneumoniae infection in a mouse model were investigated. Mice were administrated intranasally with 20 μg of B5 twice and challenged with K. pneumoniae three days after B5 pretreatment. Results showed that B5 failed to directly kill K. pneumoniae in vitro, but it provided effective protection against multidrug-resistant K. pneumoniae via decreasing the bacterial load in the lungs and spleen, and by alleviating K. pneumoniae-induced histopathological damage in the lungs. Furthermore, B5 significantly enhanced the mRNA expression of TNF-α, IL-1β, Cxcl1, Cxcl5, Ccl17, and Ccl22 and obviously enhanced the rapid recruitment of macrophages and dendritic cells in the lungs in the early infection phase, but significantly down-regulated the levels of TNF-α, IL-1β, and IL-17 in the lungs in the later infection phase. Moreover, RNA-seq results showed that K. pneumoniae infection activated signaling pathways related to natural killer cell-mediated cytotoxicity, IL-17 signaling pathway, inflammatory response, apoptosis, and necroptosis in the lungs, while B5 inhibited these signaling pathways. Additionally, K. pneumoniae challenge led to the suppression of glycerophospholipid metabolism, the phosphotransferase system, the activation of microbial metabolism in diverse environments, and metabolic pathways in the lungs. However, B5 significantly reversed these metabolic responses. Collectively, B5 can effectively regulate the inflammatory response caused by K. pneumoniae and offer protection against K. pneumoniae. B5 may be applied as an adjuvant to the existing antimicrobial therapy to control multidrug-resistant K. pneumoniae infection. Our study highlights the potential of B5 in enhancing pulmonary bacterial clearance and alleviating K. pneumoniae-caused inflammatory damage. Full article

Diabetes-related ulcers and slow-healing wounds pose a significant health risk to individuals due to their uncertain causes. Mortality rates for diabetes foot ulcers (DFUs) range from 10% after 16 months to 24% after five years. The use of bioactive phytochemicals can play a key role in healing wounds in a predictable time. Recent literature has demonstrated that various natural substances, including flavonoids, saponins, phenolic compounds, and polysaccharides, play key roles at different stages of the wound-healing process through diverse mechanisms. These studies have categorized the compounds according to their characteristics, bioactivities, and modes of action. In this study, we evaluated the role of natural compounds derived from plant sources that have been shown to play a crucial role in immunomodulation. Macrophages are closely involved in immunomodulation within the wound microenvironment and are key players in efferocytosis, inflammation resolution, and tissue regeneration, all of which contribute to successful wound healing. Phytochemicals and their derivatives have shown capabilities in immune regulation, including macrophage migration, nitric oxide synthase inhibition, lymphocyte and T-cell stimulation, cytokine activation, natural killer cell enhancement, and the regulation of NF-κβ, TNF-α, and apoptosis. In this review, we have studied the role of phytochemicals in immunomodulation for the resolution of diabetic wound inflammation. Full article

Endometrial Cancer (EC) is one of the most common gynecological malignancies. Despite its prevalence, molecular pathways, such as the Sonic Hedgehog (SHH) pathway, have not been extensively studied in the context of EC. This study aims to explore the clinical implications of SHH expression in EC, potentially uncovering new insights into the disease’s pathogenesis and offering valuable insights for therapeutic strategies in EC. We utilized data from The Cancer Genome Atlas (TCGA) to divide the dataset into ‘High SHH’ and ‘Low SHH’ groups based on a gene signature score derived from SHH pathway-related genes. We explored the clinical and tumor characteristics of these groups, focusing on key cancer hallmarks, including stemness, proliferation, cytolytic activity, tumor micro-environment, and genomic instability. ‘High SHH’ tumors emerged as a distinct category with favorable clinical and molecular features. These tumors exhibited lower proliferation rates, reduced angiogenesis, and diminished genomic instability, indicating a controlled and less aggressive tumor growth pattern. Moreover, ‘High SHH’ tumors displayed lower stemness, highlighting a less invasive phenotype. The immune micro-environment in ‘High SHH’ tumors was enriched with immune cell types, such as macrophage M0, monocytes, B cells, CD8 T cells, CD4 T cells, follicular helper T cells, and natural killer cells. This immune enrichment, coupled with higher cytolytic activity, suggested an improved anti-tumor immune response. Our study sheds light on the clinical significance of Sonic signaling in EC. ‘High SHH’ tumors exhibit a unique molecular and clinical profile associated with favorable cancer hallmarks, lower grades, and better survival. These findings underscore the potential utility of SHH expression as a robust prognostic biomarker, offering valuable insights for tailored therapeutic strategies in EC. Understanding the SHH pathway’s role in EC contributes to our growing knowledge of this cancer and may pave the way for more effective treatment strategies in the future. Full article

Cancer therapies have evolved from traditional chemotherapy to more precise molecular-targeted immunotherapies, which have been associated with improved side effects and outcomes. These modern strategies rely on cancer-specific biomarkers that differentiate malignant from normal cells. The B7 family of immune checkpoint molecules is crucial for cancer immune evasion and a prime therapeutic target. B7-H6, a recently identified member of the B7 family, has emerged as a promising therapeutic target. Unlike other B7 proteins, B7-H6 is not expressed in healthy tissues but is upregulated in several cancers. It binds to NKp30, activating natural killer (NK) cells and triggering immune responses against cancer cells. This review explores the expression of B7-H6 in different cancers, the factors that regulate its expression, and its intrinsic and extrinsic pathways. Additionally, we discuss potential anticancer therapies targeting B7-H6, highlighting its significance in advancing precision medicine. Understanding the role of B7-H6 in cancer immunity may inform the development of appropriate therapies that exploit its cancer-specific expression. Full article

Background: Compared with conventional chemotherapy and targeted therapy, immunotherapy has improved the treatment outlook for a variety of solid tumors, including lung cancer, colorectal cancer (CRC), and melanoma. However, it is effective only in certain patients, necessitating the search for alternative strategies to targeted immunotherapy. The deubiquitinating enzyme USP18 is known to play an important role in various aspects of the immune response, but its role in tumor immunity in CRC remains unclear. Methods: In this study, multiple online datasets were used to systematically analyze the expression, prognosis, and immunomodulatory role of USP18 in CRC. The effect of USP18 on CRC was assessed via shRNA-mediated knockdown of USP18 expression in combination with CCK-8 and colony formation assays. Finally, molecular docking analysis of USP18/ISG15 and programmed death-ligand 1 (PD-L1) was performed via HDOCK, and an ELISA was used to verify the potential of USP18 to regulate PD-L1. Results: Our study revealed that USP18 expression was significantly elevated in CRC patients and closely related to clinicopathological characteristics. The experimental data indicated that silencing USP18 significantly promoted the proliferation and population-dependent growth of CRC cells. In addition, high USP18 expression was positively correlated with the CRC survival rate and closely associated with tumor-infiltrating CD8+ T cells and natural killer (NK) cells. Interestingly, USP18 was correlated with the expression of various chemokines and immune checkpoint genes. The results of molecular docking simulations suggest that USP18 may act as a novel regulator of PD-L1 and that its deficiency may potentiate the antitumor immune response to PD-L1 blockade immunotherapy in CRC. Conclusions: In summary, USP18 shows great promise for research and clinical application as a potential target for CRC immunotherapy. Full article

Mucosal-associated invariant T cells (MAIT cells) are a subset of T cells with innate, effector-like properties that play an essential role in the immune response to microbial infections. In humans, MAIT cells are detectable in the blood, liver, and lungs, but little is known about the frequency of these cells in the bone marrow. Also, the pathogenic role, if any, of MAIT cells in the development of aplastic anemia, a disease with an exquisite origin in the bone marrow, is currently unknown. We investigated the frequency and clinical relevance of bone marrow MAIT cells in a cohort of 14 patients (60.6 ± 23 and 57% women) with aplastic anemia. MAIT cells in the bone marrow samples obtained at diagnosis were evaluated by flow cytometry, and their association with various blood cell parameters and the patients’ clinical features was analyzed. MAIT cells were detectable in the bone marrow of all patients, with considerable variations among them. Bone marrow MAIT cells expressing the activator receptor natural killer group 2D - NKG2D (NKG2D+ MAIT cells) were significantly more abundant in the specimens of the aplastic anemia patients than in patients with bone marrow failure distinct from aplastic anemia. In addition, the NKG2D+ MAIT cells positively correlated with whole blood cell counts (WBC), platelet counts, and neutrophil counts, as well as with various inflammatory markers, including neutrophil-to-lymphocyte rate (NLR), platelet-to-lymphocyte rate (PLR), and systemic inflammatory index (SII). In functional studies, bone marrow CD34+ hematopoietic cells exposed to phytohemagglutinin or bacterial-derived lipopolysaccharide and acetyl-6-formylpterin upregulated MR1 (major histocompatibility complex, class I-related, known to interact with MAIT cells) and MICA/B (MHC class I chain-related gene A, a ligand of NKG2D) proteins on their cell surface, suggesting that under stress conditions, CD34+ hematopoietic cells are more likely to interact with NKG2D+ MAIT cells. In addition, NKG2D+ MAIT cells upregulated perforin and granzyme B in response to their interaction with recombinant MICA protein in vitro. This study reports for the first time the frequency of MAIT cells in the bone marrow of patients with aplastic anemia and assesses the potential implications of these cells in the pathogenesis or progression of aplastic anemia. Full article

Endometriosis, a debilitating condition, affects one in ten women of reproductive age. Its pathophysiology remains unclear, though deficiencies in immune surveillance are thought to create an environment conducive to the evasion of ectopic endometrial cells from the immune system. Our research explores the immunological impact of endometriosis both locally and systemically, emphasizing natural killer (NK) and T cell subpopulations. We incorporated 62 female patients who underwent laparoscopic surgery; of those, 47 had endometriosis, and 15 were controls. We collected peritoneal fluid (PF) and peripheral blood (PB) samples which were tagged with monoclonal antibodies and subsequently scrutinized using flow cytometry. Our findings revealed significant differences in immunological profiles based on demographic factors and symptomatology. In the endometriosis cohort, there was an increase in PB CD56^HiCD16^dim and PF CD8⁺ CD56^dimCD16^Hi NK cells. CD16⁺ CD4 T cell levels were significantly lower in the PB of endometriosis patients who smoke. Individuals with more severe disease displayed significantly higher levels of PB CD16⁺ CD8 T cells, which also increased in those with non-menstrual pelvic pain. Dysmenorrhea severity correlated with a progressive increase in PF CD8⁺ CD56^dimCD16^Hi NK cells. These variations in specific lymphocyte subsets, namely, within NK and T cells, suggest potential immunological mechanisms in the evolution and clinical presentation of endometriosis. Full article

Background: Adult T-cell leukemia/lymphoma (ATL) is caused by human T-cell leukemia virus type 1 (HTLV-1) after a long latent infection. HTLV-1 induces the indolent or aggressive type of leukemia in 5% of HTLV-1 carriers. ATL, especially the aggressive type, is resistant to multi-agent chemotherapy. The indolent type often progresses to the aggressive type. Even in the most indolent-type cases, that is, smoldering ATL, the average survival time is 55.0 months. Case Presentation: Five patients with ATL were followed up for their clinical course after amplified natural killer cell (ANK) therapy. Four patients who received ANK therapy as first-line therapy achieved complete remission and showed long-term survival without aggressive conversion or relapse for more than 5 years. One patient was treated with multiagent chemotherapy due to acute exacerbation but relapsed 2 months later. She was subsequently treated with radiation and ANK therapy and survived for more than 6 years. Furthermore, ANK therapy enhanced the immune function of ATL patients to a level higher than that of normal individuals. Conclusions: ANK therapy has great potential as first-line treatment for ATL. Full article

Invariant natural killer T (iNKT) cells are glycolipid-reactive T cells with potent immunoregulatory properties. iNKT cells activated with the marine-sponge-derived glycolipid, α-galactosylceramide (αGC), provide a universal source of T-cell help that has shown considerable promise for a wide array of therapeutic applications. This includes harnessing iNKT-cell-mediated immune responses to adjuvant whole inactivated influenza virus (WIV) vaccines. An important concern with WIV vaccines is that under certain circumstances, they are capable of triggering vaccine-associated enhanced respiratory disease (VAERD). This immunopathological phenomenon can arise after immunization with an oil-in-water (OIW) adjuvanted WIV vaccine, followed by infection with a hemagglutinin and neuraminidase mismatched challenge virus. This elicits antibodies (Abs) that bind immunodominant epitopes in the HA2 region of the heterologous virus, which purportedly causes enhanced virus fusion activity to the host cell and increased infection. Here, we show that αGC can induce severe VAERD in pigs. However, instead of stimulating high concentrations of HA2 Abs, αGC elicits high concentrations of interferon (IFN)-γ-secreting cells both in the lungs and systemically. Additionally, we found that VAERD mediated by iNKT cells results in distinct cytokine profiles and altered adaptation of the challenge virus following infection compared to an OIW adjuvant. Overall, these results provide a cautionary note about considering the formulation of WIV vaccines with iNKT-cell agonists as a potential strategy to modulate antigen-specific immunity. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV) causes abortions, stillbirths, and dummy pregnancies. Previous studies found that PRRSV can promote secondary bacterial infections and elevate bacterial endotoxin levels, further increasing the abortion rate in sows. However, the pathways by which bacterial endotoxins invade the bodies of PRRSV(+) sows and aggravate their clinical symptoms are unknown. In this study, we established a model of PRRSV and lipopolysaccharide (LPS) working together on porcine endometrial epithelial cells (PEECs). We speculate that PRRSV and LPS affect PEECs through viral protein interaction with cytokines and cytokine receptors, natural killer cell-mediated cytotoxicity, and regulation of actin cytoskeleton signaling pathways by analyzing seq-RNA. The PRRSV proteins act on inflammatory factors and their receptors to activate chemokines-5 (CCL5), chemokines-4 (CCL4), and chemokines-8 (CCL8) mRNA expression, causing severe inflammatory reactions. In addition, the elevation of MEK1/2 factors and the integrins acting on NK cells promote the upregulation of VAV1/Tiam1, RAC, and IRSp53, leading to increased expression of Arp2/3 and F-actin in PEECs in the PRRSV + LPS(+) groups. However, the highly expressed cell microfilaments and cytoskeleton disrupt the original network structure, causing changes in the original physiological function of the PEECs. In summary, the PRRSV protein interacts with cytokines and cytokine receptors of PEECs, thereby enhancing virus-mediated chemokine factors and their receptor activity, accelerating bacterial endotoxin entry into the body and the invasion of cells. They destroy the cytoskeletal structure of the cells and increase damage to uterine tissue. Full article

Glioblastoma multiforme (GBM) is the most common type of primary malignant brain tumor and has a dismal overall survival rate. To date, no GBM therapy has yielded successful results in survival for patients beyond baseline surgical resection, radiation, and chemotherapy. Immunotherapy has taken the oncology world by storm in recent years and there has been movement from researchers to implement the immunotherapy revolution into GBM treatment. Natural killer (NK) cell-based immunotherapies are a rising candidate to treat GBM from multiple therapeutic vantage points: monoclonal antibody therapy targeting tumor-associated antigens (TAAs), immune checkpoint inhibitors, CAR-NK cell therapy, Bi-specific killer cell engagers (BiKEs), and more. NK therapies often focus on tumor antigens for targeting. Here, we reviewed some common targets analyzed in the fight for GBM immunotherapy relevant to NK cells: EGFR, HER2, CD155, and IL-13Rα2. We further propose investigating the Lectin-like Transcript 1 (LLT1) and cell surface proliferating cell nuclear antigen (csPCNA) as targets for NK cell-based immunotherapy. Full article

Spermatogenesis is a complex biological process crucial for male reproduction and is characterized by intricate interactions between testicular somatic cells and germ cells. Due to the cellular heterogeneity of the testes, investigating different cell types across developmental stages has been challenging. Single-cell RNA sequencing (scRNA-seq) has emerged as a valuable approach for addressing this limitation. Here, we conducted an unbiased transcriptomic study of spermatogenesis in sexually mature 4-month-old Hezuo pigs using 10× Genomics-based scRNA-seq. A total of 16,082 cells were collected from Hezuo pig testes, including germ cells (spermatogonia (SPG), spermatocytes (SPCs), spermatids (SPTs), and sperm (SP)) and somatic cells (Sertoli cells (SCs), Leydig cells (LCs), myoid cells (MCs), endothelial cells (ECs), and natural killer (NK) cells/macrophages). Pseudo-time analysis revealed that LCs and MCs originated from common progenitors in the Hezuo pig. Functional enrichment analysis indicated that the differentially expressed genes (DEGs) in the different types of testicular germ cells were enriched in the PI3K–AKT, Wnt, HIF-1, and adherens junction signaling pathways, while the DEGs in testicular somatic cells were enriched in ECM–receptor interaction and antigen processing and presentation. Moreover, genes related to spermatogenesis, male gamete generation, sperm part, sperm flagellum, and peptide biosynthesis were expressed throughout spermatogenesis. Using immunohistochemistry, we verified several stage-specific marker genes (such as UCHL1, WT1, SOX9, and ACTA2) for SPG, SCs, and MCs. By exploring the changes in the transcription patterns of various cell types during spermatogenesis, our study provided novel insights into spermatogenesis and testicular cells in the Hezuo pig, thereby laying the foundation for the breeding and preservation of this breed. Full article

We previously reported the structure, affinity, and anticancer activity of a bivalent bispecific natural killer cell engager (BiKE) composed of one anti-CD16a VHH and one anti-HER2 VHH fused via a linker. In this study, we explored the engineering of a tetravalent BiKE by fusing two anti-CD16a and two anti-HER2 VHHs in tandem, using bivalent BiKE as a template. The tetravalent BiKE was genetically engineered, and its tertiary structure was predicted using in silico modeling. The antigen binding and affinity of the tetravalent BiKE were assessed using ELISA, flow cytometry, and biolayer interferometry. The ability of the BiKEs to kill cancer cells was evaluated through classical and residual antibody-dependent cellular cytotoxicity (ADCC) assays. Additionally, we investigated the potential for NK cell fratricide via CD16a-CD16a crosslinking. Our results revealed that the tetravalent BiKE exhibited at least 100-fold higher affinity toward its target antigens compared to its bivalent counterpart. The residual ADCC assay indicated that the tetravalent BiKE was more effective in killing cancer cells than the bivalent BiKE, attributable to its lower K_off value, which prolonged its binding to NK cell surfaces. Fratricide assays demonstrated that neither the bivalent nor the tetravalent BiKE mediated fratricide. Notably, our findings showed that daratumumab-induced NK fratricide was restricted to CD38-CD38 crosslinking and was not related to ADCC via CD16a-CD38 crosslinking. This study is the first in the literature to show the successful engineering of a tetravalent immune cell engager composed of tandem VHH units, which achieves high affinity and anticancer activity without mediating fratricide. Full article

The use of chimeric antigen receptors (CAR T-cells) for the treatment of patients with malignant haematological diseases has become a well-established application for conditions such as refractory or relapsed B-cell acute lymphoblastic leukaemia (B-ALL), B-cell lymphomas (BCL), and multiple myeloma (MM). Nearly 35,000 patients have received autologous CAR T-cells for the treatment of these conditions only in the USA. Since their approval by the Food and Drug Administration (FDA) in 2017, over 1200 clinical trials have been initiated globally and there are at least 10 different CAR T-cells with approval by different regulatory agencies around the globe. In the USA, the FDA has approved six commercial CAR T-cells that are widely distributed worldwide. At the time of writing, several clinical trials have been performed in patients with solid tumours such as glioblastoma, renal and pancreatic cancer, as well as in patients with autoimmune conditions such as systemic lupus erythematosus (SLE), idiopathic inflammatory myositis (IIM), and systemic sclerosis (SS). There are also several studies showing the potential benefit of CAR T-cells for other non-malignant diseases such as asthma and even fungal infections. In this review, without pretending to cover all current areas of treatments with CAR T-cells, we offer a brief summary of some of the most relevant aspects of the use of CAR T-cells for some of these conditions. Full article

The disruption of hematopoietic and immune functions is a significant consequence of the long-term effects of radiation exposure. This study investigated the potential mechanisms by which ferulic acid (FA) acts as a radioprotective agent in mitigating radiation-induced immune damage. C57BL/6J mice were exposed to a dose of 6.0 Gy of ⁶⁰Co γ irradiation. FA was administered at doses of 25, 50, and 100 mg/kg/d for 7 days before and 30 days following irradiation. We evaluated changes in peripheral blood cells, T and B lymphocytes, natural killer cells in the spleen, and hematopoietic stem/progenitor cells in the bone marrow (BM). Whole-genome transcriptome sequencing of BM was performed to explore potential mechanisms. FA administration resulted in a significant reduction in malonaldehyde levels (p < 0.0001), an increase in catalase and beta-nicotinamide adenine dinucleotide levels in serum (p < 0.05), and enhanced multipotent progenitors (p < 0.01) and common lymphoid progenitors (p < 0.05) in the BM. Additionally, there was an elevation in white blood cell levels, red blood cell levels, and hemoglobin levels in peripheral blood (p < 0.01). Transcriptome analysis indicated that FA reversed the radiation-induced expression of genes related to immunity and inflammation. Enzyme-linked immunosorbent assay experiments further demonstrated that FA reduced interleukin-6 levels in the BM and decreased JAK1, JAK2, and STAT3 protein content (p < 0.01). In conclusion, FA might mitigate hematopoietic and immune damage by modulating the JAK/STAT signaling pathway. Full article