Calcineurin-nuclear factor of activated T cells (CN-NFAT) inhibitors are widely clinically used drugs for immunosuppression, but besides their required T cell response inhibition, they also undesirably affect innate immune cells. Disruption of innate immune cell function can explain the observed susceptibility of CN-NFAT inhibitor-treated patients to opportunistic fungal infections. Neutrophils play an essential role in innate immunity as a defense against pathogens; however, the effect of CN-NFAT inhibitors on neutrophil function was poorly described. Thus, we tested the response of human neutrophils to opportunistic fungal pathogens, namely Candida albicans and Aspergillus fumigatus, in the presence of CN-NFAT inhibitors. Here, we report that the NFAT pathway members were expressed in neutrophils and mediated part of the neutrophil response to pathogens. Upon pathogen exposure, neutrophils underwent profound transcriptomic changes with subsequent production of effector molecules. Importantly, genes and proteins involved in the regulation of the immune response and chemotaxis, including the chemokines CCL2, CCL3, and CCL4 were significantly upregulated. The presence of CN-NFAT inhibitors attenuated the expression of these chemokines and impaired the ability of neutrophils to chemoattract other immune cells. Our results amend knowledge about the impact of CN-NFAT inhibition in human neutrophils.
- MeSH
- Aspergillus fumigatus imunologie MeSH
- Candida albicans imunologie MeSH
- chemotaxe MeSH
- kalcineurin * metabolismus MeSH
- lidé MeSH
- mykózy imunologie MeSH
- neutrofily * imunologie metabolismus MeSH
- signální transdukce * MeSH
- transkripční faktory NFATC * metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
From the beginning of 2020, an urgent need to understand the pathophysiology of SARS-CoV-2 disease (COVID-19), much of which is due to dysbalanced immune responses, resonates across the world. COVID-19-associated neutrophilia, increased neutrophil-to-lymphocyte ratio, aberrant neutrophil activation, and infiltration of neutrophils into lungs suggest that neutrophils are important players in the disease immunopathology. The main objective of this study was to assess the phenotypic and functional characteristics of neutrophils in COVID-19 patients, with particular focus on the interaction between neutrophils and T cells. We hypothesize that the altered functional characteristics of COVID-19 patient-derived neutrophils result in skewed Th1/Th17 adaptive immune response, thus contributing to disease pathology. The expansion of G-MDSC and immature forms of neutrophils was shown in the COVID-19 patients. In the COVID-19 neutrophil/T cell cocultures, neutrophils caused a strong polarity shift toward Th17, and, conversely, a reduction of IFNγ-producing Th1 cells. The Th17 promotion was NOS dependent. Neutrophils, the known modulators of adaptive immunity, skew the polarization of T cells toward the Th17 promotion and Th1 suppression in COVID-19 patients, contributing to the discoordinated orchestration of immune response against SARS-CoV-2. As IL-17 and other Th17-related cytokines have previously been shown to correlate with the disease severity, we suggest that targeting neutrophils and/or Th17 represents a potentially beneficial therapeutic strategy for severe COVID-19 patients.
- MeSH
- aktivace neutrofilů * MeSH
- buňky Th17 imunologie patologie MeSH
- COVID-19 imunologie patologie MeSH
- interleukin-17 imunologie MeSH
- lidé MeSH
- neutrofily imunologie patologie MeSH
- SARS-CoV-2 imunologie MeSH
- Th1 buňky imunologie patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
IL-2 was initially characterized as a T cell growth factor in the 1970s, and has been studied intensively ever since. Decades of research have revealed multiple and diverse roles for this potent cytokine, indicating a unique linking role between adaptive and innate arms of the immune system. Here, we review the literature showing that IL-2 is expressed in a plethora of cell types across the immune system, where it has indispensable functions in orchestrating cellular interactions and shaping the nature and magnitude of immune responses. Emerging from the basic research that has revealed the molecular mechanisms and the complexity of the biologic actions of IL-2, several immunotherapeutic approaches have now focused on manipulating the levels of this cytokine in patients. These strategies range from inhibition of IL-2 to achieve immunosuppression, to the application of IL-2 as a vaccine adjuvant and in cancer therapies. This review will systematically summarize the major findings in the field and identify key areas requiring further research in order to realize the potential of IL-2 in the treatment of human diseases.
Calcineurin (CN) inhibitors are effective clinical immunosuppressants but leave patients vulnerable to potentially fatal fungal infections. This study tested the hypothesis that CN inhibition interferes with antifungal immune defenses mediated by monocytes. We showed that NFAT is expressed by human monocytes, and is activated by exposure to fungal ligands. We confirmed that NFAT translocation potently activated target gene transcription using a human monocytic reporter cell line. Inhibition of CN-NFAT by cyclosporine A significantly reduced monocyte production of TNF-α, IL-10, and MCP-1 proteins in response to pattern recognition receptor ligands as well as to Aspergillus fumigatus conidia. Moreover, we revealed that human monocytes express the antifungal protein pentraxin-3 under control of NFAT. In conclusion, clinical CN inhibitors have the potential to interfere with the novel NFAT-dependent pentraxin-3 pathway as well as antifungal cytokine production in human monocytes, thereby impeding monocyte-mediated defenses against fungal infection in immune-suppressed patients.
- MeSH
- antifungální látky metabolismus MeSH
- Aspergillus fumigatus účinky léků MeSH
- C-reaktivní protein metabolismus MeSH
- chemokiny metabolismus MeSH
- cyklosporin farmakologie MeSH
- inhibitory kalcineurinu farmakologie MeSH
- interleukin-10 metabolismus MeSH
- lidé MeSH
- monocyty účinky léků metabolismus MeSH
- myeloidní buňky účinky léků metabolismus MeSH
- myši MeSH
- sekvence nukleotidů MeSH
- sekvenční homologie aminokyselin MeSH
- sérový amyloidový protein metabolismus MeSH
- signální transdukce účinky léků MeSH
- THP-1 buňky MeSH
- TNF-alfa metabolismus MeSH
- transkripční faktory NFATC metabolismus MeSH
- transport proteinů účinky léků MeSH
- vazebná místa MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The release of neutrophil extracellular traps (NETs) is one of the weapons neutrophils have in their armory. NETs consist of extracellular chromatin fibers decorated with a plethora of cytoplasmic and granular proteins, such as the antimicrobial serine protease neutrophil elastase (NE). Because the first description of NETs as beneficial to the host, reports on their double-faced role in health and disease have considerably increased recently. On one hand, NETs reportedly trap and kill bacteria and also participate in the resolution of the acute inflammation associated with infection and with tissue damage. On the other hand, numerous negative aspects of NETs contribute to the etiopathogenesis of autoimmune disorders. Employing soluble and solid fluorescent substrates, we demonstrate the interaction of NE with aggregated NETs (aggNETs), the limitation of its enzymatic activity and the containment of the enzyme from surrounding tissues. These events prevent the spread of inflammation and tissue damage. The detection of DNase 1-dependent elevation of NE activity attests the continuous presence of patrolling neutrophils forming NETs and aggNETs even under conditions physiologic conditions.
- MeSH
- aktivace enzymů MeSH
- deoxyribonukleasa I metabolismus MeSH
- deoxyribonukleasy metabolismus MeSH
- extracelulární pasti imunologie metabolismus MeSH
- leukocytární elastasa metabolismus MeSH
- lidé MeSH
- myši MeSH
- neutrofily imunologie metabolismus MeSH
- tělesné tekutiny metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Eye rheum is a physiological discharge, which accumulates at the medial angle of the healthy eye soon after opening in the morning. Microscopic evaluation of eye rheum revealed the presence of viable neutrophils, bacteria, epithelial cells, and particles, aggregated by neutrophil extracellular traps. We observed that in the evening, during eye closure, high C5a recruited neutrophils to the tear film and activated them. In this hypoxic area rich in CO2 , neutrophils fight microbial aggressors by degranulation. Immediately after eye opening, the microenvironment of the ocular surface changes, the milieu gets normoxic, and loss of CO2 induces subtle alkalinization of tear film. These conditions favored the formation of neutrophil extracellular traps (NETs) that initially covers the ocular surface and tend to aggregate by eyelid blinking. These aggregated neutrophil extracellular traps (aggNETs) are known as eye rheum and contain several viable neutrophils, epithelial cells, dust particles, and crystals packed together by NETs. Similar to aggNETs induced by monosodium urate crystals, the eye rheum shows a robust proteolytic activity that degraded inflammatory mediators before clinically overt inflammation occur. Finally, the eye rheum passively floats with the tear flow to the medial angle of the eye for disposal. We conclude that the aggNETs-based eye rheum promotes cleaning of the ocular surface and ameliorates the inflammation on the neutrophil-rich ocular surfaces.
The plasminogen system is harnessed in a wide variety of physiological processes, such as fibrinolysis, cell migration, or efferocytosis; and accordingly, it is essential upon inflammation, tissue remodeling, wound healing, and for homeostatic maintenance in general. Previously, we identified a plasminogen receptor in the mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R, CD222). Here, we demonstrate by means of genetic knockdown, knockout, and rescue approaches combined with functional studies that M6P/IGF2R is up-regulated on the surface of macrophages, recognizes plasminogen exposed on the surface of apoptotic cells, and mediates plasminogen-induced efferocytosis. The level of uptake of plasminogen-coated apoptotic cells inversely correlates with the TNF-α production by phagocytes indicating tissue clearance without inflammation by this mechanism. Our results reveal an up-to-now undetermined function of M6P/IGF2R in clearance of apoptotic cells, which is crucial for tissue homeostasis.
- MeSH
- buněčná diferenciace účinky léků MeSH
- fagocytóza účinky léků MeSH
- fibroblasty účinky léků metabolismus MeSH
- genový knockout MeSH
- Jurkat buňky MeSH
- lidé MeSH
- makrofágy cytologie účinky léků metabolismus MeSH
- myši MeSH
- plazminogen farmakologie MeSH
- receptor IGF typ 2 metabolismus MeSH
- THP-1 buňky MeSH
- TNF-alfa metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Glycosaminoglycans have anti-inflammatory properties and interact with a variety of soluble and membrane-bound molecules. Little is known about their effects on B cells and humoral immune responses. We show that CS but not dextran or other glycosaminoglycans induces a pronounced proliferation of B cells in vitro compared with TLR4 or TLR9 ligands. With the use of inhibitors and KO mice, we demonstrate that this proliferation is mediated by the tyrosine kinases BTK and Syk but independent of CD44. Antibodies against Ig-α or Ig-β completely block CS-induced B cell proliferation. Injection of CS in mice for 4-5 days expands B cells in the spleen and results in a marked increase of CD138(+) cells in the spleen that is dependent on BTK but independent of CD4(+) T cells. Long-term treatment with CS for 14 days also increases CD138(+) cells in the bone marrow. When mice were immunized with APC or collagen and treated with CS for up to 14 days during primary or after secondary immune responses, antigen-specific humoral immune responses and antigen-specific CD138(+) plasma cells in the bone marrow were reduced significantly. These data show that CD138(+) cells, induced by treatment with CS, migrate into the bone marrow and may displace other antigen-specific plasma cells. Overall, CS is able to interfere markedly with primary and fully established humoral immune responses in mice.
- MeSH
- aktivace lymfocytů účinky léků genetika MeSH
- antigeny CD44 genetika imunologie MeSH
- buňky kostní dřeně imunologie MeSH
- chondroitin sulfáty farmakologie MeSH
- humorální imunita účinky léků genetika MeSH
- intracelulární signální peptidy a proteiny genetika imunologie MeSH
- myši inbrední BALB C MeSH
- myši knockoutované MeSH
- myši MeSH
- plazmatické buňky imunologie MeSH
- pohyb buněk účinky léků imunologie MeSH
- proliferace buněk účinky léků MeSH
- syndekan-1 genetika imunologie MeSH
- toll-like receptor 4 genetika imunologie MeSH
- toll-like receptor 9 genetika imunologie MeSH
- tyrosinkinasy genetika imunologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Membrane rafts are microdomains of the plasma membrane that have multiple biological functions. The involvement of these structures in the biology of T cells, namely in signal transduction by the TCR, has been widely studied. However, the role of membrane rafts in immunoreceptor signaling in NK cells is less well known. We studied the distribution of the activating NKG2D receptor in lipid rafts by isolating DRMs in a sucrose density gradient or by raft fractionation by β-OG-selective solubility in the NKL cell line. We found that the NKG2D-DAP10 complex and pVav are recruited into rafts upon receptor stimulation. Qualitative proteomic analysis of these fractions showed that the actin cytoskeleton is involved in this process. In particular, we found that the actin-bundling protein L-plastin plays an important role in the clustering of NKG2D into lipid rafts. Moreover, coengagement of the inhibitory receptor NKG2A partially disrupted NKG2D recruitment into rafts. Furthermore, we demonstrated that L-plastin participates in NKG2D-mediated inhibition of NK cell chemotaxis.
- MeSH
- buněčná membrána účinky léků metabolismus MeSH
- buňky NK cytologie metabolismus MeSH
- centrifugace - gradient hustoty MeSH
- chemotaxe leukocytů fyziologie MeSH
- detergenty farmakologie MeSH
- kultivované buňky MeSH
- lektinové receptory NK-buněk - podrodina C metabolismus MeSH
- lektinové receptory NK-buněk - podrodina K fyziologie MeSH
- lidé MeSH
- malá interferující RNA farmakologie MeSH
- membránové mikrodomény účinky léků fyziologie MeSH
- mikrofilamenta fyziologie MeSH
- mikrofilamentové proteiny antagonisté a inhibitory genetika fyziologie MeSH
- multiproteinové komplexy MeSH
- proteom MeSH
- receptory imunologické metabolismus MeSH
- RNA interference MeSH
- signální transdukce imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The histamine H4 receptor regulates the inflammatory response. However, it is not known whether this receptor has a functional role in human neutrophils. We found that fMLP (1 μM), but not histamine (0.1-1 μM), induced Mac-1-dependent adhesion, polarization, and degranulation (release of lactoferrin). A pretreatment of neutrophils with histamine (0.001-1 μM) or JNJ 28610244 (0.1-10 μM), a specific H4 receptor agonist, led to inhibition of degranulation. Total inhibition of degranulation was obtained with 0.1 μM histamine and 10 μM JNJ 28610244. Furthermore, such inhibition by histamine of degranulation was reversed by JNJ 7777120 and JNJ 28307474, two selective H4 receptor antagonists. However, neither histamine nor the H4 receptor agonist JNJ 28610244 prevented fMLP-induced, Mac-1-dependent adhesion, indicating that the H4 receptor may block signals emanating from Mac-1-controlling degranulation. Likewise, engagement of the H4 receptor by the selective agonist JNJ 28610244 blocked Mac-1-dependent activation of p38 MAPK, the kinase that controls neutrophil degranulation. We also show expression of the H4 receptor at the mRNA level in ultrapure human neutrophils and myeloid leukemia PLB-985 cells. We concluded that engagement of this receptor by selective H4 receptor agonists may represent a good, therapeutic approach to accelerate resolution of inflammation.
- MeSH
- akutní promyelocytární leukemie patologie MeSH
- antigen-1 spojený s lymfocytární funkcí chemie MeSH
- buněčná adheze účinky léků fyziologie MeSH
- cytochalasin B farmakologie MeSH
- degranulace buněk * účinky léků MeSH
- fibrinogen MeSH
- histamin farmakologie MeSH
- indoly farmakologie MeSH
- konformace proteinů účinky léků MeSH
- kultivované buňky MeSH
- lidé MeSH
- makrofágový antigen 1 fyziologie MeSH
- MAP kinasový signální systém účinky léků MeSH
- messenger RNA biosyntéza genetika MeSH
- mitogenem aktivované proteinkinasy p38 fyziologie MeSH
- N-formylmethionin-leucyl-fenylalanin farmakologie MeSH
- nádorové buněčné linie MeSH
- neutrofily účinky léků fyziologie MeSH
- oximy farmakologie MeSH
- piperaziny farmakologie MeSH
- piperidiny farmakologie MeSH
- pyridiny farmakologie MeSH
- receptory histaminu fyziologie MeSH
- receptory spřažené s G-proteiny agonisté antagonisté a inhibitory fyziologie MeSH
- tvar buňky účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
