scholarly journals Activation of MAIT cells plays a critical role in viral vector vaccine immunogenicity

2019 ◽  
Author(s):  
Nicholas M. Provine ◽  
Ali Amini ◽  
Lucy C. Garner ◽  
Christina Dold ◽  
Claire Hutchings ◽  
...  
Keyword(s):  
Cell Activation ◽  
Viral Vector ◽  
Critical Role ◽  
Vector Vaccine ◽  
Future Design ◽  
Mait Cells ◽  
Lethal Infection ◽  
Mait Cell

AbstractMucosal-associated invariant T (MAIT) cells can be activated by viruses through a cytokine-dependent mechanism, and thereby protect from lethal infection. Given this, we reasoned MAIT cells may have a critical role in the immunogenicity of replication-incompetent adenovirus vectors, which are novel and highly potent vaccine platforms. In vitro, ChAdOx1 (Chimpanzee Adenovirus Ox1) induced potent activation of MAIT cells. Activation required transduction of monocytes and plasmacytoid dendritic cells to produce IL-18 and IFN-α, respectively. IFN-α-induced monocyte-derived TNF-α was identified as a novel intermediate in this activation pathway, and activation required combinatorial signaling of all three cytokines. Furthermore, ChAdOx1-induced in vivo MAIT cell activation in both mice and human volunteers. Strikingly, MAIT cell activation was necessary in vivo for development of ChAdOx1-induced HCV-specific CD8 T cell responses. These findings define a novel role for MAIT cells in the immunogenicity of viral vector vaccines, with potential implications for future design.One sentence summaryRobust immunogenicity of candidate adenovirus vaccine vectors requires the activation of unconventional T cells.

scholarly journals Influenza A Virus Infection v1

2020 ◽  
Author(s):  
Timothy S C Hinks ◽  
Bonnie van Wilgenburg ◽  
Huimeng Wang ◽  
Liyen Loh ◽  
Marios Koutsakos ◽  
...  
Keyword(s):  
Influenza A ◽  
Cell Activation ◽  
Viral Infections ◽  
Intracellular Cytokine Staining ◽  
Cell Receptor ◽  
Type I ◽  
Independent Manner ◽  
Mait Cells ◽  
Mait Cell

This is part 3.3 of the "Study of MAIT Cell Activation in Viral Infections In Vivo" collection of protocols. Collection Abstract: MAIT cells are abundant, highly evolutionarily conserved innate-like lymphocytes expressing a semi-invariant T cell receptor (TCR), which recognizes microbially derived small intermediate molecules from the riboflavin biosynthetic pathway. However, in addition to their TCR-mediated functions they can also be activated in a TCR-independent manner via cytokines including IL-12, -15, -18, and type I interferon. Emerging data suggest that they are expanded and activated by a range of viral infections, and significantly that they can contribute to a protective anti-viral response. Here we describe methods used to investigate these anti-viral functions in vivo in murine models. To overcome the technical challenge that MAIT cells are rare in specific pathogen-free laboratory mice, we describe how pulmonary MAIT cells can be expanded using intranasal bacterial infection or a combination of synthetic MAIT cell antigen and TLR agonists. We also describe protocols for adoptive transfer of MAIT cells, methods for lung homogenization for plaque assays, and surface and intracellular cytokine staining to determine MAIT cell activation.

scholarly journals Sustained IFN-I stimulation impairs MAIT cell responses to bacteria by inducing IL-10 during chronic HIV-1 infection

2020 ◽  
Vol 6 (8) ◽  
pp. eaaz0374 ◽  
Author(s):  
X. Tang ◽  
S. Zhang ◽  
Q. Peng ◽  
L. Ling ◽  
H. Shi ◽  
...  
Keyword(s):  
Cell Activation ◽  
Surface Protein ◽  
Interleukin 10 ◽  
Mait Cells ◽  
Cell Dysfunction ◽  
Cell Responses ◽  
High Level ◽  
Hiv 1 ◽  
Mait Cell

Mucosal-associated invariant T (MAIT) cells in HIV-1–infected individuals are functionally impaired by poorly understood mechanisms. Single-cell transcriptional and surface protein analyses revealed that peripheral MAIT cells from HIV-1–infected subjects were highly activated with the up-regulation of interferon (IFN)–stimulated genes as compared to healthy individuals. Sustained IFN-α treatment suppressed MAIT cell responses to Escherichia coli by triggering high-level interleukin-10 (IL-10) production by monocytes, which subsequently inhibited the secretion of IL-12, a crucial costimulatory cytokine for MAIT cell activation. Blocking IFN-α or IL-10 receptors prevented MAIT cell dysfunction induced by HIV-1 exposure in vitro. Moreover, blocking the IL-10 receptor significantly improved anti–Mycobacterium tuberculosis responses of MAIT cells from HIV-1–infected patients. Our findings demonstrate the central role of the IFN-I/IL-10 axis in MAIT cell dysfunction during HIV-1 infection, which has implications for the development of anti–IFN-I/IL-10 strategies against bacterial coinfections in HIV-1–infected patients.

Cathepsin B inhibition prevents trypsinogen activation and reduces pancreatitis severity

2002 ◽  
Vol 283 (3) ◽  
pp. G794-G800 ◽  
Author(s):  
Gijs J. D. van Acker ◽  
Ashok K. Saluja ◽  
Lakshmi Bhagat ◽  
Vijay P. Singh ◽  
Albert M. Song ◽  
...  
Keyword(s):  
Acute Pancreatitis ◽  
Acinar Cell ◽  
Cathepsin B ◽  
Cell Activation ◽  
Cell Injury ◽  
Critical Role ◽  
Trypsinogen Activation ◽  
Soluble Cell

Intrapancreatic activation of trypsinogen is believed to play a critical role in the initiation of acute pancreatitis, but mechanisms responsible for intrapancreatic trypsinogen activation during pancreatitis have not been clearly defined. In previous in vitro studies, we have shown that intra-acinar cell activation of trypsinogen and acinar cell injury in response to supramaximal secretagogue stimulation could be prevented by the cell permeant cathepsin B inhibitor E64d (Saluja A, Donovan EA, Yamanaka K, Yamaguchi Y, Hofbauer B, and Steer ML. Gastroenterology 113: 304–310, 1997). The present studies evaluated the role of intrapancreatic trypsinogen activation, this time under in vivo conditions, in two models of pancreatitis by using another highly soluble cell permeant cathepsin B inhibitor,l-3-trans-(propylcarbamoyl)oxirane-2-carbonyl-l-isoleucyl-l-proline methyl ester (CA-074me). Intravenous administration of CA-074me (10 mg/kg) before induction of either secretagogue-elicited pancreatitis in mice or duct infusion-elicited pancreatitis in rats markedly reduced the extent of intrapancreatic trypsinogen activation and substantially reduced the severity of both pancreatitis models. These observations support the hypothesis that, during the early stages of pancreatitis, trypsinogen activation in the pancreas is mediated by the lysosomal enzyme cathepsin B. Our findings also suggest that pharmacological interventions that inhibit cathepsin B may prove useful in preventing acute pancreatitis or reducing its severity.

scholarly journals Lung Homogenization v1

2020 ◽  
Author(s):  
Timothy S C Hinks ◽  
Bonnie van Wilgenburg ◽  
Huimeng Wang ◽  
Liyen Loh ◽  
Marios Koutsakos ◽  
...  
Keyword(s):  
Cell Activation ◽  
Viral Infections ◽  
Intracellular Cytokine Staining ◽  
Cell Receptor ◽  
Type I ◽  
Independent Manner ◽  
Mait Cells ◽  
Specific Pathogen ◽  
Mait Cell

This is part 3.4 of the "Study of MAIT Cell Activation in Viral Infections In Vivo" collection of protocols. Collection Abstract: MAIT cells are abundant, highly evolutionarily conserved innate-like lymphocytes expressing a semi-invariant T cell receptor (TCR), which recognizes microbially derived small intermediate molecules from the riboflavin biosynthetic pathway. However, in addition to their TCR-mediated functions they can also be activated in a TCR-independent manner via cytokines including IL-12, -15, -18, and type I interferon. Emerging data suggest that they are expanded and activated by a range of viral infections, and significantly that they can contribute to a protective anti-viral response. Here we describe methods used to investigate these anti-viral functions in vivo in murine models. To overcome the technical challenge that MAIT cells are rare in specific pathogen-free laboratory mice, we describe how pulmonary MAIT cells can be expanded using intranasal bacterial infection or a combination of synthetic MAIT cell antigen and TLR agonists. We also describe protocols for adoptive transfer of MAIT cells, methods for lung homogenization for plaque assays, and surface and intracellular cytokine staining to determine MAIT cell activation.

scholarly journals MAIT Cell Adoptive Transfer v1

2020 ◽  
Author(s):  
Timothy S C Hinks ◽  
Bonnie van Wilgenburg ◽  
Huimeng Wang ◽  
Liyen Loh ◽  
Marios Koutsakos ◽  
...  
Keyword(s):  
Adoptive Transfer ◽  
Cell Activation ◽  
Viral Infections ◽  
Intracellular Cytokine Staining ◽  
Cell Receptor ◽  
Type I ◽  
Independent Manner ◽  
Mait Cells ◽  
Mait Cell

This is part 3.2 of the "Study of MAIT Cell Activation in Viral Infections In Vivo" collection of protocols. Collection Abstract: MAIT cells are abundant, highly evolutionarily conserved innate-like lymphocytes expressing a semi-invariant T cell receptor (TCR), which recognizes microbially derived small intermediate molecules from the riboflavin biosynthetic pathway. However, in addition to their TCR-mediated functions they can also be activated in a TCR-independent manner via cytokines including IL-12, -15, -18, and type I interferon. Emerging data suggest that they are expanded and activated by a range of viral infections, and significantly that they can contribute to a protective anti-viral response. Here we describe methods used to investigate these anti-viral functions in vivo in murine models. To overcome the technical challenge that MAIT cells are rare in specific pathogen-free laboratory mice, we describe how pulmonary MAIT cells can be expanded using intranasal bacterial infection or a combination of synthetic MAIT cell antigen and TLR agonists. We also describe protocols for adoptive transfer of MAIT cells, methods for lung homogenization for plaque assays, and surface and intracellular cytokine staining to determine MAIT cell activation.

scholarly journals Interleukin (IL)-12 and IL-18 Synergize to Promote MAIT Cell IL-17A and IL-17F Production Independently of IL-23 Signaling

2020 ◽  
Vol 11 ◽  
Author(s):  
Suzanne Cole ◽  
Janine Murray ◽  
Catherine Simpson ◽  
Remi Okoye ◽  
Kerry Tyson ◽  
...  
Keyword(s):  
Th17 Cells ◽  
Cell Activation ◽  
Retinoic Acid Receptor ◽  
Γδ T Cells ◽  
Lymphoid Cells ◽  
Orphan Receptor ◽  
Mait Cells ◽  
Activation Assay ◽  
Mait Cell

IL-23 is considered a critical regulator of IL-17 in Th17 cells; however, its requirement for inducing IL-17 production in other human immune subsets remains incompletely understood. Mucosal associated invariant T (MAIT) cells uniformly express retinoic acid receptor-related orphan receptor gamma t (RORγt) but only a minor population have been shown to produce IL-17A. Here we show that IL-17F is the dominant IL-17 isoform produced by MAIT cells, not IL-17A. For optimal MAIT cell derived IL-17A and IL-17F production, T cell receptor (TCR) triggering, IL-18 and monocyte derived IL-12 signaling is required. Unlike Th17 cells, this process is independent of IL-23 signaling. Using an in vitro skin cell activation assay, we demonstrate that dual neutralization of both IL-17A and IL-17F resulted in greater suppression of inflammatory proteins than inhibition of IL-17A alone. Finally, we extend our findings by showing that other innate-like lymphocytes such as group 3 innate lymphoid cells (ILC3) and gamma delta (γδ) T cells are also capable of IL-23 independent IL-17A and IL-17F production. These data indicate both IL-17F and IL-17A production from MAIT cells may contribute to tissue inflammation independently of IL-23, in part explaining the therapeutic disconnect between targeting IL-17 or IL-23 in certain inflammatory diseases.

Magnoliae Flos Essential Oil as an Immunosuppressant in Dendritic Cell Activation and Contact Hypersensitivity Responses

2020 ◽  
Vol 48 (03) ◽  
pp. 597-613 ◽  
Author(s):  
Chun-Hsien Chen ◽  
Hsin-Chun Chen ◽  
Wen-Te Chang ◽  
Meng-Shiou Lee ◽  
Yi-Chen Liu ◽  
...  
Keyword(s):  
Essential Oil ◽  
Cell Activation ◽  
Nasal Congestion ◽  
Critical Role ◽  
Adaptive Immune Response ◽  
Contact Hypersensitivity ◽  
Dendritic Cell Activation ◽  
Chinese Texts

Magnoliae Flos is a commonly used traditional medicinal material in Asia. It is used to treat sinusitis, nasal congestion, and hypersensitive skin. Because Magonlia Flos was described as an aromatic material in ancient Chinese texts, we hypothesized that its essential oil may be used to treat immune disorders. Dendritic cells (DCs), regarded as a major target of immunomodulators to control immune responses, play a critical role in the adaptive immune response. In this study, Magnoliae Flos essential oil (MFEO) decreased the production of the cytokines TNF-[Formula: see text], IL-6, and IL-12p70 in lipopolysaccharide (LPS)-stimulated DCs. It also suppressed the surface markers MHC II, CD80, and CD86 in LPS-stimulated DCs. Animal models demonstrated that the 2,4-Dinitro-1-fluorobenzene (DNFB) inducing a contact hypersensitivity response was inhibited following treatment with MFEO. In addition, MFEO inhibited the infiltration of T cells in the ears of DNFB-induced mice. To explore its bioactive compounds, the components of MFEO were analyzed using gas chromatography (GC) and GC-mass spectrometry. The results revealed that the major compounds in MFEO are camphor and 1,8-cineole. Additional DC bioassays confirmed that these compounds substantially suppressed cytokine production in LPS-induced DCs. Therefore, we demonstrated that MFEO exhibits an immunosuppressive effect both in vivo and in vitro, and camphor and 1,8-cineole may be the major components responsible for its immunosuppressive ability. The findings indicate that MFEO has the potential to be developed as a new immunosuppressant for excessive diseases.

scholarly journals Interleukin-18 Is Critical for Mucosa-Associated Invariant T Cell Gamma Interferon Responses toFrancisellaSpeciesIn Vitrobut NotIn Vivo

2018 ◽  
Vol 86 (5) ◽  
Author(s):  
Eric Jesteadt ◽  
Irma Zhang ◽  
Huifeng Yu ◽  
Anda Meierovics ◽  
Wei-Jen Chua Yankelevich ◽  
...  
Keyword(s):  
Pulmonary Infection ◽  
Gamma Interferon ◽  
Interleukin 18 ◽  
Class I Mhc ◽  
Content Type ◽  
Mait Cells ◽  
Ifn Γ ◽  
Mait Cell

ABSTRACTMucosa-associated invariant T (MAIT) cells are a subset of innate T cells that express a semi-invariant Vα chain paired with limited Vβ chains. MAIT cells are activated by riboflavin metabolite derivatives presented by the nonpolymorphic major histocompatibility complex class I (MHC-I)-like molecule MR1. The precise mechanisms required to activate MAIT cells are an area of intense interest. Here we used two closely related intracellular pathogens with distinct inflammasome activation phenotypes to probe the role of innate cytokines in MAIT cell activation. Using anin vitroassay containing transgenic murine MAIT cells, we show that macrophages infected withFrancisella novicida, a strong inflammasome activator, released high levels of interleukin-18 (IL-18) and stimulated high levels of MAIT cell gamma interferon (IFN-γ) through a partially MR1-independent pathway. In contrast, macrophages infected withFrancisella tularensislive vaccine strain (LVS), a weak inflammasome activator, generated little IL-18 and stimulated low MAIT cell IFN-γ through an MR1-dependent pathway. By manipulating the quantities of IL-18 in these cultures, we show that the IL-18 concentration is sufficient to influence the magnitude of MAIT cell IFN-γ production. Correspondingly, infected IL-18-deficient macrophages failed to induce substantial MAIT cell IFN-γ. In contrast, we found that MAIT cell IFN-γ production in the lungs of IL-18-deficient mice was not significantly different from that in WT mice duringF. tularensisLVS pulmonary infection. Overall, we demonstrate that while IL-18 is essential for the MAIT cell IFN-γ responsein vitro, it is not essential for MAIT cell IFN-γ production duringin vivoLVS pulmonary infection, suggesting that additional signals can drive MAIT cell IFN-γ productionin vivo.

scholarly journals Viral Plaque Assay v1

2020 ◽  
Author(s):  
Timothy S C Hinks ◽  
Bonnie van Wilgenburg ◽  
Huimeng Wang ◽  
Liyen Loh ◽  
Marios Koutsakos ◽  
...  
Keyword(s):  
Cell Activation ◽  
Viral Infections ◽  
Mdck Cells ◽  
Intracellular Cytokine Staining ◽  
Type I ◽  
Tissue Culture Dish ◽  
Mait Cells ◽  
Viral Plaque ◽  
Mait Cell

This is part 3.6 of the "Study of MAIT Cell Activation in Viral Infections In Vivo" collection of protocols. Collection Abstract: MAIT cells are abundant, highly evolutionarily conserved innate-like lymphocytes expressing a semi-invariant T cell receptor (TCR), which recognizes microbially derived small intermediate molecules from the riboflavin biosynthetic pathway. However, in addition to their TCR-mediated functions they can also be activated in a TCR-independent manner via cytokines including IL-12, -15, -18, and type I interferon. Emerging data suggest that they are expanded and activated by a range of viral infections, and significantly that they can contribute to a protective anti-viral response. Here we describe methods used to investigate these anti-viral functions in vivo in murine models. To overcome the technical challenge that MAIT cells are rare in specific pathogen-free laboratory mice, we describe how pulmonary MAIT cells can be expanded using intranasal bacterial infection or a combination of synthetic MAIT cell antigen and TLR agonists. We also describe protocols for adoptive transfer of MAIT cells, methods for lung homogenization for plaque assays, and surface and intracellular cytokine staining to determine MAIT cell activation. Abstract: Viral plaque assays are used to determine influenza viral titers. A diluted solution of egg-adapted Influenza A viruses/lung-infected tissue homogenates are applied to a six-well tissue culture dish containing a monolayer of Madin-Darby canine kidney (MDCK) cells. The infected MDCK cells grow under a semisolid overlay medium (agar) containing trypsin. A plaque is produced when a virus particle infects a cell, replicates, and then kills the cell. This process can be repeated several times as surrounding cells can be infected by newly replicated virus and killed. When visualized by eye, plaques appear as white spots. The assay is measured in PFU/mL.

scholarly journals Study of MAIT Cell Activation in Viral Infections In Vivo v1

2020 ◽  
Author(s):  
Timothy S C Hinks ◽  
Bonnie van Wilgenburg ◽  
Huimeng Wang ◽  
Liyen Loh ◽  
Marios Koutsakos ◽  
...  
Keyword(s):  
Cell Activation ◽  
Viral Infections ◽  
Intracellular Cytokine Staining ◽  
Cell Receptor ◽  
Type I ◽  
Independent Manner ◽  
Mait Cells ◽  
Specific Pathogen ◽  
Mait Cell

MAIT cells are abundant, highly evolutionarily conserved innate-like lymphocytes expressing a semi-invariant T cell receptor (TCR), which recognizes microbially derived small intermediate molecules from the riboflavin biosynthetic pathway. However, in addition to their TCR-mediated functions they can also be activated in a TCR-independent manner via cytokines including IL-12, -15, -18, and type I interferon. Emerging data suggest that they are expanded and activated by a range of viral infections, and significantly that they can contribute to a protective anti-viral response. Here we describe methods used to investigate these anti-viral functions in vivo in murine models. To overcome the technical challenge that MAIT cells are rare in specific pathogen-free laboratory mice, we describe how pulmonary MAIT cells can be expanded using intranasal bacterial infection or a combination of synthetic MAIT cell antigen and TLR agonists. We also describe protocols for adoptive transfer of MAIT cells, methods for lung homogenization for plaque assays, and surface and intracellular cytokine staining to determine MAIT cell activation.

Sign in / Sign up

Export Citation Format

Share Document