| 1. |
- Bartsch, Yannic C, et al.
(författare)
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IgG Fc sialylation is regulated during the germinal center reaction upon immunization with different adjuvants
- 2020
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Ingår i: The Journal of Allergy and Clinical Immunology. - : Elsevier BV. - 1097-6825 .- 0091-6749. ; 146:3, s. 652-666
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Effector functions of IgG antibodies (Abs) are regulated by their Fc N-glycosylation pattern. IgG Fc glycans that lack galactose and terminal sialic acid residues correlate with the severity of inflammatory (auto)immune disorders and have also been linked to the protection against viral infection and discussed in the context of vaccine-induced protection. In contrast, sialylated IgG Abs have shown immunosuppressive effects.OBJECTIVE: We sought to investigate IgG glycosylation programming during the germinal center (GC) reaction upon immunization of mice with a foreign protein antigen and different adjuvants.METHODS: Mice were analyzed for GC T, B cell and plasma cell responses as well as antigen-specific serum IgG subclass titers and Fc glycosylation patterns.RESULTS: Different adjuvants induce distinct IgG+ GC B cell responses with specific transcriptomes and expression levels of the α2,6-sialyltransferase responsible for IgG sialylation that correspond to distinct serum IgG Fc glycosylation patterns. Low IgG Fc sialylation programming in GC B cells was overall highly dependent on the T follicular helper (TFH) cell-inducing cytokine IL-6, especially induced by water-in-oil adjuvants and Mycobacterium tuberculosis (Mtb). Furthermore, low IgG Fc sialylation programming was dependent on adjuvants that induced IL-27R-dependent IFNγ+ TFH1 cells, IL-6/IL-23-dependent IL-17A+ TFH17 cells and high TFH/T follicular regulatory (TFR) cell ratios. The two latter were here dependent on Mtb and its cord factor.CONCLUSION: These findings on adjuvant-dependent GC responses and IgG glycosylation programming may aid the development of novel vaccination strategies to induce IgG Abs with both high affinity and defined Fc glycosylation patterns.
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| 2. |
- Bros, Matthias, et al.
(författare)
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Mutated cylindromatosis gene affects the functional state of dendritic cells
- 2010
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Ingår i: European Journal of Immunology. - : Wiley. - 1521-4141 .- 0014-2980. ; 40:10, s. 2848-2857
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Tidskriftsartikel (refereegranskat)abstract
- Cylindromatosis gene (CYLD) is a ubiquitously expressed deubiquitinating enzyme, which interacts with members of the NF-kappa B signaling pathway and attenuates NF-kappa B and JNK signaling. Here, we report that DC derived from transgenic mice, which solely express a naturally occurring CYLD isoform (CYLDex7/8), display a higher content of nuclear RelB and express elevated levels of NF-kappa B family members as well as of known NF-kappa B-target genes comprising costimulatory molecules and pro-inflammatory cytokines, as compared with WT DC. Accordingly, unstimulated CYLDex7/8 DC exhibited a significantly higher primary allogenic T-cell stimulatory capacity than WT DC and exerted no tolerogenic activity. Transduction of unstimulated CYLDex7/8 DC with relB-specific shRNA reduced their T-cell stimulatory capacity. Treatment with the synthetic glucocorticoid dexamethasone known to inhibit NF-kappa B and AP-1 activity reverted the pro-immunogenic phenotype and function of CYLDex7/8 DC and re-established their tolerogenic function. DC derived from CYLD knockout mice showed no functional alterations compared with WT DC. Therefore, although complete loss of CYLD may be compensated for by other endogenous NF-kappa B inhibitors, CYLDex7/8 acts in a dominant negative manner. Our findings raise the question of whether genetic defects associated with increased NF-kappa B activity may result in disturbed maintenance of peripheral tolerance.
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| 3. |
- Matsuwaki, Takashi, 1978-, et al.
(författare)
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Involvement of interleukin-1 type 1 receptors in lipopolysaccharide-induced sickness responses
- 2017
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Ingår i: Brain, behavior, and immunity. - : Elsevier. - 0889-1591 .- 1090-2139. ; 66, s. 165-176
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Tidskriftsartikel (refereegranskat)abstract
- Sickness responses to lipopolysaccharide (LPS) were examined in mice with deletion of the interleukin (IL)-1 type 1 receptor (IL-1R1). IL-1R1 knockout (1(0) mice displayed intact anorexia and HPA-axis activation to intraperitoneally injected LPS (anorexia: 10 or 120 mu g/kg; HPA-axis: 120 mu g/kg), but showed attenuated but not extinguished fever (120 g/kg). Brain PGE2 synthesis was attenuated, but Cox-2 induction remained intact. Neither the tumor necrosis factor-alpha (TNF alpha) inhibitor etanercept nor the IL -6 receptor antibody tocilizumab abolished the LPS induced fever in IL -1R1 KO mice. Deletion of IL -1R1 specifically in brain endothelial cells attenuated the LPS induced fever, but only during the late, 3rd phase of fever, whereas deletion of IL-1R1 on neural cells or on peripheral nerves had little or no effect on the febrile response. We conclude that while IL-1 signaling is not critical for LPS induced anorexia or stress hormone release, IL-1R1, expressed on brain endothelial cells, contributes to the febrile response to LPS. However, also in the absence of IL-1R1, LPS evokes a febrile response, although this is attenuated. This remaining fever seems not to be mediated by IL-6 receptors or TNFa, but by some yet unidentified pyrogenic factor.
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| 4. |
- Rizk, John, et al.
(författare)
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SMAC mimetics promote NIK-dependent inhibition of CD4+ TH17 cell differentiation
- 2019
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Ingår i: Science Signaling. - : American Association for the Advancement of Science (AAAS). - 1945-0877 .- 1937-9145. ; 12:596
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Tidskriftsartikel (refereegranskat)abstract
- Second mitochondria-derived activator of caspase (SMAC) mimetics (SMs) are selective antagonists of the inhibitor of apoptosis proteins (IAPs), which activate noncanonical NF-B signaling and promote tumor cell death. Through gene expression analysis, we found that treatment of CD4+ T cells with SMs during T helper 17 (TH17) cell differentiation disrupted the balance between two antagonistic transcription factor modules. Moreover, proteomics analysis revealed that SMs altered the abundance of proteins associated with cell cycle, mitochondrial activity, and the balance between canonical and noncanonical NF-B signaling. Whereas SMs inhibited interleukin-17 (IL-17) production and ameliorated TH17 cell-driven inflammation, they stimulated IL-22 secretion. Mechanistically, SM-mediated activation of NF-B-inducing kinase (NIK) and the transcription factors RelB and p52 directly suppressed Il17a expression and IL-17A protein production, as well as the expression of a number of other immune genes. Induction of IL-22 production correlated with the NIK-dependent reduction in cMAF protein abundance and the enhanced activity of the aryl hydrocarbon receptor. Last, SMs also increased IL-9 and IL-13 production and, under competing conditions, favored the differentiation of naïve CD4+ T cells into TH2 cells rather than TH17 cells. These results demonstrate that SMs shape the gene expression and protein profiles of TH17 cells and inhibit TH17 cell-driven autoimmunity.
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| 5. |
- Srokowski, Cathy Cecilia, et al.
(författare)
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Naturally occurring short splice variant of CYLD positively regulates dendritic cell function
- 2009
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 113:23, s. 5891-5895
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Tidskriftsartikel (refereegranskat)abstract
- Deubiquitination of NF-kappa B members by CYLD is crucial in controlling the magnitude and nature of cell activation. The role of the naturally occurring CYLD splice variant in dendritic cell (DC) function was analyzed using CYLDex7/8 mice, which lack the full-length CYLD (flCYLD) transcript and overexpress the short splice variant (sCYLD). Bone marrow-derived DCs from CYLDex7/8 mice display a hyperactive phenotype in vitro and in vivo and have a defect in establishing tolerance with the use of DEC-205-mediated antigen targeting to resting DCs. The combination of sCYLD overexpression and lack of flCYLD in CYLDex7/8 DCs leads to enhanced NF-kappa B activity accompanied by an increased nuclear translocation of the I kappa B molecule Bcl-3, along with nuclear p50 and p65. This suggests that, in contrast to flCYLD, sCYLD is a positive regulator of NF-kappa B activity, and its overexpression induces a hyperactive phenotype in DCs. (Blood. 2009; 113: 5891-5895)
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| 6. |
- van Montfoort, Nadine, et al.
(författare)
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Circulating specific antibodies enhance systemic cross-priming by delivery of complexed antigen to dendritic cells in vivo
- 2012
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Ingår i: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 42:3, s. 598-606
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Tidskriftsartikel (refereegranskat)abstract
- Increasing evidence suggests that antibodies can have stimulatory effects on T-cell immunity. However, the contribution of circulating antigen-specific antibodies on MHC class I cross-priming in vivo has not been conclusively established. Here, we defined the role of circulating antibodies in cross-presentation of antigen to CD8+ T cells. Mice with hapten-specific circulating antibodies, but naϊve for the T-cell antigen, were infused with haptenated antigen and CD8+ T-cell induction was measured. Mice with circulating hapten-specific antibodies showed significantly enhanced cross-presentation of the injected antigen compared with mice that lacked these antibodies. The enhanced cross-presentation in mice with circulating antigen-specific antibodies was associated with improved antigen capture by APCs. Importantly, CD11c+ APCs were responsible for the enhanced and sustained cross-presentation, although CD11c− APCs had initially captured a significant amount of the injected antigen. Thus, in vivo formation of antigen-antibody immune complexes improves MHC class I cross-presentation, and CD8+ T-cell activation, demonstrating that humoral immunity can aid the initiation of systemic cellular immunity. These findings have important implications for the understanding of the action of therapeutic antibodies against tumor-associated antigens intensively used in the clinic nowadays.
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| 7. |
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