Beyond target cell death - Granzyme serine proteases in health and disease

Remodeling of the extracellular matrix by serine proteases as a prerequisite for cancer initiation and progression

The extracellular matrix (ECM) serves as a physical scaffold for tissues that is composed of structural proteins such as laminins, collagens, proteoglycans and fibronectin, forming a three dimensional network, and a wide variety of other matrix proteins with ECM-remodeling and signaling functions. The activity of ECM-associated signaling proteins is tightly regulated. Thus, the ECM serves as a reservoir for water and growth regulatory signals. The ECM architecture is dynamically modulated by multiple serine proteases that process both structural and signaling proteins to regulate physiological processes such as organogenesis and tissue homeostasis but they also contribute to pathological events, especially cancer progression. Here, we review the current literature regarding the role of ECM remodeling by serine proteases (KLKs, uPA, furin, HtrAs, granzymes, matriptase, hepsin) in tumorigenesis.

Upregulation of granzyme B and C-X3-C motif receptor 1 in circulating plasmablasts was negatively regulated by Notch signal in patients with systemic lupus erythematosus

As one molecule related to cytotoxicity, surface expression of C-X3-C motif receptor 1 (CX3CR1) was highly correlated with intracellular granzyme B (GZMB) in natural killer and cytolytic T cells. However, the expression of CX3CR1 and GZMB in B cells has not been clarified, and their clinical significance in systemic lupus erythematosus (SLE) remains unclear. This study aimed to clarify the changes and clinical significance of peripheral blood B cells expressing GZMB and/or CX3CR1 in SLE. Peripheral blood was collected from 39 patients with SLE and 48 healthy controls. We found that GZMB and CX3CR1 expression varied in different B-cell subsets, with plasmablasts possessing the highest positive percentages, consistent with bioinformatics prediction. GZMB+ and CX3CR1+ percentages in circulating B cells and plasmablasts were increased in patients with SLE. CX3CR1 was upregulated on B cells after in vitro stimulation. Notch intracellular domain expression was significantly decreased in plasmablasts of patients with SLE, and CX3CR1 in plasmablasts was downregulated with the addition of JAG1. In conclusion, GZMB and CX3CR1 were increased in B cells and in plasmablasts of patients with SLE and CX3CR1 was negatively regulated by Notch signal in plasmablasts, which may be involved in SLE pathogenesis.

Overview of multifunctional Tregs in cardiovascular disease: From insights into cellular functions to clinical implications

Regulatory T cells (Tregs) are crucial in regulating T-cell-mediated immune responses. Numerous studies have shown that dysfunction or decreased numbers of Tregs may be involved in inflammatory cardiovascular diseases (CVDs) such as atherosclerosis, hypertension, myocardial infarction, myocarditis, cardiomyopathy, valvular heart diseases, heart failure, and abdominal aortic aneurysm. Tregs can help to ameliorate CVDs by suppressing excessive inflammation through various mechanisms, including inhibition of T cells and B cells, inhibition of macrophage-induced inflammation, inhibition of dendritic cells and foam cell formation, and induction of anti-inflammatory macrophages. Enhancing or restoring the immunosuppressive activity of Tregs may thus serve as a fundamental immunotherapy to treat hypertension and CVDs. However, the precise molecular mechanisms underlying the Tregs-induced protection against hypertension and CVDs remain to be investigated. This review focuses on recent advances in our understanding of Tregs subsets and function in CVDs. In addition, we discuss promising strategies for using Tregs through various pharmacological approaches to treat hypertension and CVDs.

Assessment of In Vitro Antioxidant and Anti-Inflammatory Activities of Pumpkin (Cucurbita pepo) Natural Plant

Objectives

The objective of this research was to investigate the potential anti-inflammatory properties of the Cucurbita pepo fruit. Given the adverse effects associated with long-term use or excessive doses of conventional anti-inflammatory medications, exploring herbal therapies as alternatives has become increasingly important.

Methods

Various preliminary tests and antioxidant assays, both enzymatic and non-enzymatic, were conducted on the C . pepo fruit. Bioactive substances present in the fruit, including alkaloids, carbohydrates, flavonoids, tannins, amino acids, triterpenoids, and saponin glycosides, were identified through early analysis. Different extraction solvents, such as chloroform, methanol, and water, were utilized to extract samples. The methanolic extract was subjected to further testing for its in vitro anti-inflammatory characteristics. This involved evaluating their ability to stabilize RBC membranes, inhibit protein denaturation, and suppress proteinase activity using two concentrations (150 µg/ml and 300 µg/ml) of the extract.

Results

The methanolic extract of the C. pepo fruit exhibited strong free radical scavenging activity in both DPPH and H2O2 assays. Moreover, it demonstrated the dose-dependent stabilization of RBC membranes, resulting in reduced hemolysis, protein denaturation, and proteinase activity. These findings suggest potent anti-inflammatory effects of the methanolic extract.

Conclusion

This research study has found that the C. pepo fruit methanolic extract significantly reduced inflammation. This demonstrates the promise of natural chemicals as less risky substitutes for traditional anti-inflammatory medications. Potentially safe and efficient treatments for inflammatory illnesses could be found in herbal remedies such as the C. pepo fruit. Therefore, this study highlights the significance of exploring herbal remedies as a potential treatment option for inflammation-related diseases.

Granzymes in health and diseases: the good, the bad and the ugly

Granzymes are a family of serine proteases, composed of five human members: GA, B, H, M and K. They were first discovered in the 1980s within cytotoxic granules released during NK cell- and T cell-mediated killing. Through their various proteolytic activities, granzymes can trigger different pathways within cells, all of which ultimately lead to the same result, cell death. Over the years, the initial consideration of granzymes as mere cytotoxic mediators has changed due to surprising findings demonstrating their expression in cells other than immune effectors as well as new intracellular and extracellular activities. Additional roles have been identified in the extracellular milieu, following granzyme escape from the immunological synapse or their release by specific cell types. Outside the cell, granzyme activities mediate extracellular matrix alteration via the degradation of matrix proteins or surface receptors. In certain contexts, these processes are essential for tissue homeostasis; in others, excessive matrix degradation and extensive cell death contribute to the onset of chronic diseases, inflammation, and autoimmunity. Here, we provide an overview of both the physiological and pathological roles of granzymes, highlighting their utility while also recognizing how their unregulated presence can trigger the development and/or worsening of diseases.

Role of pyroptosis in the pathogenesis of various neurological diseases

Pyroptosis, an inflammatory programmed cell death process, has recently garnered significant attention due to its pivotal role in various neurological diseases. This review delves into the intricate molecular signaling pathways governing pyroptosis, encompassing both caspase-1 dependent and caspase-1 independent routes, while emphasizing the critical role played by the inflammasome machinery in initiating cell death. Notably, we explore the Nucleotide-binding domain leucine-rich repeat (NLR) containing protein family, the Absent in melanoma 2-like receptor family, and the Pyrin receptor family as essential activators of pyroptosis. Additionally, we comprehensively examine the Gasdermin family, renowned for their role as executioner proteins in pyroptosis. Central to our review is the interplay between pyroptosis and various central nervous system (CNS) cell types, including astrocytes, microglia, neurons, and the blood-brain barrier (BBB). Pyroptosis emerges as a significant factor in the pathophysiology of each cell type, highlighting its far-reaching impact on neurological diseases. This review also thoroughly addresses the involvement of pyroptosis in specific neurological conditions, such as HIV infection, drug abuse-mediated pathologies, Alzheimer's disease, and Parkinson's disease. These discussions illuminate the intricate connections between pyroptosis, chronic inflammation, and cell death in the development of these disorders. We also conducted a comparative analysis, contrasting pyroptosis with other cell death mechanisms, thereby shedding light on their unique aspects. This approach helps clarify the distinct contributions of pyroptosis to neuroinflammatory processes. In conclusion, this review offers a comprehensive exploration of the role of pyroptosis in various neurological diseases, emphasizing its multifaceted molecular mechanisms within various CNS cell types. By elucidating the link between pyroptosis and chronic inflammation in the context of neurodegenerative disorders and infections, it provides valuable insights into potential therapeutic targets for mitigating these conditions.

Potential Immunoregulatory Mechanism of Plant Saponins: A Review

Saponins are extracted from different parts of plants such as seeds, roots, stems, and leaves and have a variety of biological activities including immunomodulatory, anti-inflammatory effects, and hypoglycemic properties. They demonstrate inherent low immunogenicity and possess the capacity to effectively regulate both the innate and adaptive immune responses. Plant saponins can promote the growth and development of the body's immune organs through a variety of signaling pathways, regulate the activity of a variety of immune cells, and increase the secretion of immune-related cytokines and antigen-specific antibodies, thereby exerting the role of immune activity. However, the chemical structure of plant saponins determines its certain hemolytic and cytotoxicity. With the development of science and technology, these disadvantages can be avoided or reduced by certain technical means. In recent years, there has been a significant surge in interest surrounding the investigation of plant saponins as immunomodulators. Consequently, the objective of this review is to thoroughly examine the immunomodulatory properties of plant saponins and elucidate their potential mechanisms, with the intention of offering a valuable point of reference for subsequent research and advancement within this domain.

Identification of PANoptosis-related biomarkers and immune infiltration characteristics in psoriasis

BACKGROUND

PANoptosis may play a vital role in psoriasis. We investigated the relationship between PANoptosis in psoriasis.

METHODS

Genes information was mainly obtained from GeneCards and the gene expression omnibus database. Genefunctions identification was based on gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses. Gene set enrichment analysis was used to identify enriched signaling pathways in psoriasis. We constructed PPI networks using the search tool for the retrieval of interacting genes database and Cytoscape and explored mRNA-miRNA, mRNA-TF, and mRNA-drug interaction networks. Receiver operating characteristic curves were performed to screen potential biomarkers among these hub genes. Immune cell infiltration was analyzed using the Pearson algorithm, and the correlation between immune-cell abundance and PANoptosis-related differentially expressed gene (PDGs) was investigated.

RESULTS

We identified 10 PDGs, which were mainly involved in pyroptosis, cytokine-mediated signaling pathways, Salmonella infection and NOD-like receptor signaling pathway. The activated pathways were mostly proinflammatory and immunoregulatory pathways between immune cells. BAK1, CASP4, IL18, and IRF1 were identified as hub genes in the mRNA-miRNA network, and BAK1, IRF1, and PYCARD were hub genes in the mRNA-TF network. CASP1 was found to be the most targeted gene by drugs or molecular compounds. We found PDGs were positively associated with proinflammatory immune cell infiltration and negatively associated with anti-inflammatory or regulatory immune cells.

CONCLUSION

We confirmed the role of PANoptosis in psoriasis for the first time and predicted hub genes and immune characteristics, which provides new ideas for further investigation of psoriasis on pathogenic mechanisms and therapeutic strategies.

Transcriptomic Approaches in Studies on and Applications of Chimeric Antigen Receptor T Cells

Chimeric antigen receptor T (CAR-T) cells are specifically modified T cells which bear recombinant receptors, present at the cell surface and devoted to detect selected antigens of cancer cells, and due to the presence of transmembrane and activation domains, able to eliminate the latter ones. The use of CAR-T cells in anti-cancer therapies is a relatively novel approach, providing a powerful tool in the fight against cancer and bringing new hope for patients. However, despite huge possibilities and promising results of preclinical studies and clinical efficacy, there are various drawbacks to this therapy, including toxicity, possible relapses, restrictions to specific kinds of cancers, and others. Studies desiring to overcome these problems include various modern and advanced methods. One of them is transcriptomics, a set of techniques that analyze the abundance of all RNA transcripts present in the cell at certain moment and under certain conditions. The use of this method gives a global picture of the efficiency of expression of all genes, thus revealing the physiological state and regulatory processes occurring in the investigated cells. In this review, we summarize and discuss the use of transcriptomics in studies on and applications of CAR-T cells, especially in approaches focused on improved efficacy, reduced toxicity, new target cancers (like solid tumors), monitoring the treatment efficacy, developing novel analytical methods, and others.

Resisting T cell attack: tumor-cell-intrinsic defense and reparation mechanisms

Cytotoxic T lymphocytes (CTLs) are antigen-specific killer cells equipped to identify and eliminate host cells that have been altered through infection or transformation. Both chimeric antigen-receptor (CAR) T cell therapies and immune checkpoint blockade (ICB) therapies are based on successful elimination of tumor cells by cytotoxic effectors. In this opinion article, we outline cell-intrinsic mechanisms by which tumor cells defend against CTLs, highlighting pathways that confer resistance and proposing opportunities for combination therapies. We discuss how exogenous killing entities [e.g., supramolecular attack particles (SMAPs)] offer a novel strategy to circumvent cellular resistance mechanisms. Our opinion article highlights the importance of identifying, quantifying, and targeting tumor defense mechanisms at the interface between tumor cells and CTLs as a critical consideration in the development of immunotherapy approaches.

The roles of ERIANIN in tumor and innate immunity and its' perspectives in immunotherapy

Traditional Chinese medicine has been used in China for thousands of years. In 2022, the 14th Five-Year Plan for the Development of Traditional Chinese Medicine was released, aiming to enhance traditional Chinese medicine health services and improve policies and systems for high-quality traditional Chinese medicinal development by 2025. ERIANIN, the main component of the traditional Chinese medicine Dendrobium, plays an important role in anti-inflammatory, antiviral, antitumor, antiangiogenic, and other pharmacological effects. ERIANIN has broad-spectrum antitumor effects, and its tumor-suppressive effects have been confirmed in the study of various diseases, such as precancerous lesions of the stomach, gastric cancer, liver cancer, lung cancer, prostate cancer, bladder cancer, breast cancer, cervical cancer, osteosarcoma, colorectal cancer, leukaemia, nasopharyngeal cancer and melanoma through the multiple signaling pathways. Thus, the aim of this review was to systematically summarise the research on ERIANIN with the aim of serving as a reference for future research on this compound and briefly discuss some future perspectives development of ERIANIN in combined immunotherapy.