-
Pathogens (Basel, Switzerland) May 2024Disseminated leishmaniasis (DL) caused by is characterized by the presence of 10 to more than 1000 lesions spread on the body. While protection against is mediated by...
Disseminated leishmaniasis (DL) caused by is characterized by the presence of 10 to more than 1000 lesions spread on the body. While protection against is mediated by macrophages upon activation by IFN-γ produced by CD4T cells, the pathology of disseminated leishmaniasis (DL) could be mediated by macrophages, NK, and CD8T cells. Herein, we evaluate the participation of senescent CD8T cells in the pathogenesis of DL. Peripheral blood mononuclear cells (PBMCs), biopsies, co-cultures of CD8T cells with uninfected and infected macrophages (MØ), and PBMC cultures stimulated with soluble antigen (SLA) for 72 h from patients with cutaneous leishmaniasis (CL) and DL were used to characterize senescent CD8T cells. Statistical analysis was performed using the Mann-Whitney and Kruskal-Wallis tests, followed by Dunn's. Patients with DL have an increase in the frequency of circulating CD8T cells that present a memory/senescent phenotype, while lesions from DL patients have an increase in the frequency of infiltrating CD8T cells with a senescent/degranulation phenotype. In addition, after specific stimuli, DL patients' circulating CD8T with memory/senescent profile, showing degranulation characteristics, increased upon SLA stimuli, and those specific CD8T cells from DL patients had an increased degranulation phenotype, causing more apoptosis of infected target cells. DL patients show a higher frequency of cytotoxic senescent CD8T cells compared to CL patients, and that could promote the lysis of infected cells, although without parasite killing, releasing to the extracellular compartment, contributing to the spread of parasites.
PubMed: 38921758
DOI: 10.3390/pathogens13060460 -
Advances in Respiratory Medicine May 2024Ragweed pollen allergy is the most common seasonal allergy in western Romania. Prolonged exposure to ragweed pollen may induce sensitization to pan-allergens such as...
Ragweed pollen allergy is the most common seasonal allergy in western Romania. Prolonged exposure to ragweed pollen may induce sensitization to pan-allergens such as calcium-binding proteins (polcalcins) and progression to more severe symptoms. We aimed to detect IgE sensitization to recombinant Amb a 9 and Amb a 10 in a Romanian population, to assess their potential clinical relevance and cross-reactivity, as well as to investigate the relation with clinical symptoms. rAmb a 9 and rAmb a 10 produced in were used to detect specific IgE in sera from 87 clinically characterized ragweed-allergic patients in ELISA, for basophil activation experiments and rabbit immunization. Rabbit rAmb a 9- and rAmb a 10-specific sera were used to detect possible cross-reactivity with rArt v 5 and reactivity towards ragweed and mugwort pollen extracts. The results showed an IgE reactivity of 25% to rAmb a 9 and 35% to rAmb a 10. rAmb a 10 induced basophil degranulation in three out of four patients tested. Moreover, polcalcin-negative patients reported significantly more skin symptoms, whereas polcalcin-positive patients tended to report more respiratory symptoms. Furthermore, both rabbit antisera showed low reactivity towards extracts and showed high reactivity to rArt v 5, suggesting strong cross-reactivity. Our study indicated that recombinant ragweed polcalcins might be considered for molecular diagnosis.
Topics: Humans; Immunoglobulin E; Cross Reactions; Rhinitis, Allergic, Seasonal; Romania; Calcium-Binding Proteins; Antigens, Plant; Allergens; Female; Male; Ambrosia; Rabbits; Adult; Plant Extracts
PubMed: 38921061
DOI: 10.3390/arm92030022 -
Nature Biotechnology Jun 2024Natural killer (NK) cells have clinical potential against cancer; however, multiple limitations hinder the success of NK cell therapy. Here, we performed unbiased...
Natural killer (NK) cells have clinical potential against cancer; however, multiple limitations hinder the success of NK cell therapy. Here, we performed unbiased functional mapping of tumor-infiltrating NK (TINK) cells using in vivo adeno-associated virus (AAV)-SB (Sleeping Beauty)-CRISPR (clustered regularly interspaced short palindromic repeats) screens in four solid tumor mouse models. In parallel, we characterized single-cell transcriptomic landscapes of TINK cells, which identified previously unexplored subpopulations of NK cells and differentially expressed TINK genes. As a convergent hit, CALHM2-knockout (KO) NK cells showed enhanced cytotoxicity and tumor infiltration in mouse primary NK cells and human chimeric antigen receptor (CAR)-NK cells. CALHM2 mRNA reversed the CALHM2-KO phenotype. CALHM2 KO in human primary NK cells enhanced their cytotoxicity, degranulation and cytokine production. Transcriptomics profiling revealed CALHM2-KO-altered genes and pathways in both baseline and stimulated conditions. In a solid tumor model resistant to unmodified CAR-NK cells, CALHM2-KO CAR-NK cells showed potent in vivo antitumor efficacy. These data identify endogenous genetic checkpoints that naturally limit NK cell function and demonstrate the use of CALHM2 KO for engineering enhanced NK cell-based immunotherapies.
PubMed: 38918616
DOI: 10.1038/s41587-024-02282-4 -
The Journal of Clinical Investigation Jun 2024Neutrophil infiltration occurs in a variety of liver diseases, but it is unclear how neutrophils and hepatocytes interact. Neutrophils generally use granule proteases to...
Neutrophil infiltration occurs in a variety of liver diseases, but it is unclear how neutrophils and hepatocytes interact. Neutrophils generally use granule proteases to digest phagocytosed bacteria and foreign substances or neutralize them in neutrophil extracellular traps. In certain pathological states, granule proteases play a destructive role against the host as well. More recently, non-destructive actions of neutrophil granule proteins have been reported, such as modulation of tissue remodeling and metabolism. Here we report a completely different mechanism by which neutrophils act non-destructively, by inserting granules directly into hepatocytes. Specifically, elastase-containing granules were transferred to hepatocytes where elastase selectively degraded intracellular calcium channels to reduce cell proliferation without cytotoxicity. In response, hepatocytes increased expression of serpin E2 and A3, which inhibited elastase activity. Elastase insertion was seen in patient specimens of alcohol-associated hepatitis, and the relationship between elastase-mediated ITPR2 degradation and reduced cell proliferation was confirmed in mouse models. Moreover, neutrophils from patients with alcohol-associated hepatitis were more prone to degranulation and more potent in reducing calcium channel expression than neutrophils from healthy subjects. This non-destructive and reversible action on hepatocytes defines a previously unrecognized role for neutrophils in the transient regulation of epithelial calcium signaling mechanisms.
PubMed: 38916955
DOI: 10.1172/JCI171691 -
Journal of Leukocyte Biology Jun 2024Effector CD4+ T lymphocytes (Teff) infiltrate sites of inflammation and orchestrate the immune response by instructing local leukocytes. Mast cells (MCs) are tissue...
Effector CD4+ T lymphocytes (Teff) infiltrate sites of inflammation and orchestrate the immune response by instructing local leukocytes. Mast cells (MCs) are tissue sentinel cells strategically located near blood vessels and T cell rich areas. MC/Teff cells interactions shape Teff cell responses but in turn, Teff cell action on MC is still poorly understood. Here, we analyzed the human MC/Teff cells interplay through both the application of RNAseq and functional assays. We showed that activated Teff cells induce a specific transcriptomic program in MCs including production of both inflammatory cytokines and chemokines, prostaglandin, and a FcεRI-dependent degranulation facilitation thereby driving them toward an inflammatory phenotype. Moreover, Teff cells induce in MCs the capacity to interact with CD4+ T cell through a wide-range of dedicated soluble and membrane ligands and to play the role of antigen presenting cells (APCs).
PubMed: 38916515
DOI: 10.1093/jleuko/qiae139 -
Veterinary Research Communications Jun 2024Mastitis represents the biggest threat to the health and productivity of dairy cows, leading to substantial economic losses in milk production. It manifests in two...
Mastitis represents the biggest threat to the health and productivity of dairy cows, leading to substantial economic losses in milk production. It manifests in two forms: clinical mastitis, easily diagnosed by visible symptoms, and subclinical mastitis (SCM), which lacks overt clinical signs. SCM's elusive nature often results in it going undetected, thus facilitating the spread of the disease-causing agent due to lack of treatment. Finding a reliable biomarker for early SCM would reduce the possibility of mastitis spreading in the herd, reduce the need for antibiotic use and ultimately reduce milk losses for producers. Utilizing state-of-the-art proteomics techniques, 138 milk samples from dairy cows in continental Croatia underwent analysis. These samples were categorized into four groups based on the Zagreb Mastitis Test (ZMT) and microbiological analysis: lowSCC- (n = 20), lowSCC + (n = 20), medSCC + (n = 79), and highSCC + (n = 19). A total of 386 proteins were identified and quantified, with 76 proteins showing significant differential abundances among the groups. Many of these proteins are linked to the innate immune system, as well as neutrophil and platelet degranulation processes. Through fold changes observed between groups, 15 proteins exhibiting biomarker characteristics for subclinical mastitis (SCM) were identified. Among these, five proteins-cathelicidins (-1, -4, and -7), lactoferrin, and haptoglobin-showed particular promise.
PubMed: 38913241
DOI: 10.1007/s11259-024-10442-9 -
Allergy, Asthma & Immunology Research May 2024The diagnosis of anaphylaxis is based on the clinical history. The utility of tryptase measurements in clinical setting is limited. Mas-related G protein-coupled...
The diagnosis of anaphylaxis is based on the clinical history. The utility of tryptase measurements in clinical setting is limited. Mas-related G protein-coupled receptor-X2 (MRGPRX2) is expressed in mast cells and is involved in the degranulation of these cells. We evaluated the potential of MRGPRX2 as a diagnostic biomarker in patients with iodinated contrast media (ICM)-induced immediate hypersensitivity reactions (IHRs). A total of 173 patients with documented ICM-induced IHR within 4 months from registration were enrolled and skin tests for the culprit ICM were performed. The time interval was evaluated as the duration between the onset of ICM-induced IHR and the measurement of serum MRGPRX2 levels. Serum MRGPRX2 concentration was determined using an enzyme-linked immunosorbent assay kit. Of the 173 patients, 33 and 140 were included in the anaphylaxis and non-anaphylaxis groups, respectively. Serum MRGPRX2 levels were significantly higher in the anaphylaxis than in the non-anaphylaxis group (29.9 ± 24.1 vs. 20.7±17.5, = 0.044). Serum MRGPRX2 showed a moderate predictive ability for anaphylaxis, with an area under the curve of 0.61 ( = 0.058). When groups were classified based on the time interval, T1(0-2months) and T2 (2-4months), patients with anaphylaxis had higher MRGPRX2 levels compared to the non-anaphylaxis group in the T2 group (36.5±19.2 vs. 20.5±19.0, = 0.035). This pilot study shows that serum MRGPRX2 is a potential long-term biomarker for predicting anaphylaxis, particularly ICM-induced anaphylaxis. Further studies are needed to determine the role of MRGPRX2 in anaphylaxis in a larger population of patients with various drug-induced IHRs.
PubMed: 38910288
DOI: 10.4168/aair.2024.16.3.308 -
Frontiers in Neural Circuits 2024The olfactory epithelium (OE) is directly exposed to environmental agents entering the nasal cavity, leaving OSNs prone to injury and degeneration. The causes of... (Review)
Review
The olfactory epithelium (OE) is directly exposed to environmental agents entering the nasal cavity, leaving OSNs prone to injury and degeneration. The causes of olfactory dysfunction are diverse and include head trauma, neurodegenerative diseases, and aging, but the main causes are chronic rhinosinusitis (CRS) and viral infections. In CRS and viral infections, reduced airflow due to local inflammation, inflammatory cytokine production, release of degranulated proteins from eosinophils, and cell injury lead to decreased olfactory function. It is well known that injury-induced loss of mature OSNs in the adult OE causes massive regeneration of new OSNs within a few months through the proliferation and differentiation of progenitor basal cells that are subsequently incorporated into olfactory neural circuits. Although normal olfactory function returns after injury in most cases, prolonged olfactory impairment and lack of improvement in olfactory function in some cases poses a major clinical problem. Persistent inflammation or severe injury in the OE results in morphological changes in the OE and respiratory epithelium and decreases the number of mature OSNs, resulting in irreversible loss of olfactory function. In this review, we discuss the histological structure and distribution of the human OE, and the pathogenesis of olfactory dysfunction associated with CRS and viral infection.
Topics: Humans; Olfactory Mucosa; Olfaction Disorders; Olfactory Receptor Neurons; Sinusitis; Rhinitis; Animals
PubMed: 38903957
DOI: 10.3389/fncir.2024.1406218 -
Burns & Trauma 2024Bacterial infections pose a considerable threat to skin wounds, particularly in the case of challenging-to-treat diabetic wounds. Systemic antibiotics often struggle to...
BACKGROUND
Bacterial infections pose a considerable threat to skin wounds, particularly in the case of challenging-to-treat diabetic wounds. Systemic antibiotics often struggle to penetrate deep wound tissues and topically applied antibiotics may lead to sensitization, necessitating the development of novel approaches for effectively treating germs in deep wound tissues. Neutrophils, the predominant immune cells in the bloodstream, rapidly release an abundance of molecules via degranulation upon activation, which possess the ability to directly eliminate pathogens. This study was designed to develop novel neutrophil cell engineered nanovesicles (NVs) with high production and explore their bactericidal properties and application in promoting infectious wound healing.
METHODS
Neutrophils were isolated from peripheral blood and activated via phorbol myristate acetate (PMA) stimulation. Engineered NVs were prepared by sequentially extruding activated neutrophils followed by ultracentrifugation and were compared with neutrophil-derived exosomes in terms of morphology, size distribution and protein contents. The bactericidal effect of NVs was evaluated using the spread plate technique, LIVE/DEAD backlight bacteria assay and observation of bacterial morphology. The therapeutic effects of NVs were evaluated using wound contraction area measurements, histopathological examinations, assessments of inflammatory factors and immunochemical staining.
RESULTS
Activated neutrophils stimulated with PMA promptly release a substantial amount of bactericidal proteins. NVs are similar to exosomes in terms of morphology and particle size, but they exhibit a significantly higher enrichment of bactericidal proteins. , NVs demonstrated a significant bactericidal effect, presumably mediated by the enrichment of bactericidal proteins such as lysozyme. These NVs significantly accelerated wound healing, leading to a marked reduction in bacterial load, downregulation of inflammatory factors and enhanced collagen deposition in a full-thickness infectious skin defect model.
CONCLUSIONS
We developed engineered NVs derived from activated neutrophils to serve as a novel debridement method targeting bacteria in deep tissues, ultimately promoting infectious wound healing.
PubMed: 38903935
DOI: 10.1093/burnst/tkae018 -
International Immunopharmacology Jun 2024
PubMed: 38902129
DOI: 10.1016/j.intimp.2024.112497