| 1. |
- Dahlén, Eva, et al.
(författare)
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Development of interleukin-1 receptor antagonist mutants with enhanced antagonistic activity in vitro and improved therapeutic efficacy in collagen-induced arthritis.
- 2008
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Ingår i: Journal of Immunotoxicology. - : Informa UK Limited. - 1547-6901 .- 1547-691X. ; 5:2, s. 189-199
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Tidskriftsartikel (refereegranskat)abstract
- Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of the pro-inflammatory interleukin-1-mediated activation of the interleukin-1 receptor (IL-1R). Although wild-type IL-1Ra is used for treatment of inflammatory diseases, its effect is moderate and/or short-lived. The objective of this study was to generate IL-1Ra mutants with enhanced antagonistic activity for potential therapeutic use. Using a directed evolution approach in which libraries of IL-1Ra gene mutants were generated and screened in functional assays, mutants with desired properties were identified. Initially, diversity was introduced into the IL-1Ra using random mutagenesis. Mutations resulting in enhanced antagonistic activity were identified by screening in a reporter cell assay. To further enhance the antagonistic activity, selected mutations were recombined using the DNA recombination technology Fragment-INduced Diversity (FIND). Following three rounds of FIND recombination, several mutants with up to nine times enhanced antagonistic activity (mean IC50 +/- SEM value: 0.78 +/- 0.050 vs. 6.8 +/- 1.1 ng/ml for mutant and wild-type, respectively) were identified. Sequence analysis identified the mutations D47N, E52R and E90Y as being most important for this effect, however, the mutations P38Y, H54R, Q129L and M136N further enhanced the antagonistic function. Analysis of identified mutations in protein models based on the crystal structure of the IL-1Ra/IL-1R complex suggested that mutations found to enhance the antagonistic activity had a stabilizing effect on the IL-1Ra mutants or increased the affinity for the IL-1R. Finally, the therapeutic effect of one mutant was compared to that of wild-type IL-1Ra in collagen-induced arthritis in mice. Indeed, the enhanced antagonistic effect of the mutants observed in vitro was also seen in vivo. In conclusion, these results demonstrate that directed evolution of IL-1Ra is an effective means of generating highly potent therapeutic proteins.
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| 2. |
- Gustafsson, Åsa, et al.
(författare)
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Lung exposure of titanium dioxide nanoparticles induces innate immune activation and long-lasting lymphocyte response in the Dark Agouti rat
- 2011
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Ingår i: Journal of Immunotoxicology. - : Informa Healthcare. - 1547-691X .- 1547-6901. ; 8:2, s. 111-121
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Tidskriftsartikel (refereegranskat)abstract
- Nanomaterial of titanium dioxide (TiO(2)) is manufactured in large-scale production plants, resulting in risks for accidental high exposures of humans. Inhalation of metal oxide nanoparticles in high doses may lead to both acute and long-standing adverse effects. By using the Dark Agouti (DA) rat, a strain disposed to develop chronic inflammation following exposure to immunoactivating adjuvants, we investigated local and systemic inflammatory responses after lung exposure of nanosized TiO(2) particles up to 90 days after intratracheal instillation. TiO(2) induced a transient response of proinflammatory and T-cell-activating cytokines (interleukin [IL]-1α, IL-1β, IL-6, cytokine-induced neutrophil chemoattractant [CINC]-1, granulocyte-macrophage colony-stimulating factor [GM-CSF], and IL-2) in airways 1-2 days after exposure, accompanied by an influx of eosinophils and neutrophils. Neutrophil numbers remained elevated for 30 days, whereas the eosinophils declined to baseline levels at Day 8, simultaneously with an increase of dendritic cells and natural killer (NK) cells. The innate immune activation was followed by a lymphocyte expansion that persisted throughout the 90-day study. Lymphocytes recruited to the lungs were predominantly CD4(+) helper T-cells, but we also demonstrated presence of CD8(+) T-cells, B-cells, and CD25(+) T-cells. In serum, we detected both an early cytokine expression at Days 1-2 (IL-2, IL-4, IL-6, CINC-1, IL-10, and interferon-gamma [IFN-γ] and a second response at Day 16 of tumor necrosis factor-alpha (TNF-α), indicating systemic late-phase effects in addition to the local response in airways. In summary, these data demonstrate a dynamic response to TiO(2) nanoparticles in the lungs of DA rats, beginning with an innate immune activation of eosinophils, neutrophils, dendritic cells, and NK cells, followed by a long-lasting activation of lymphocytes involved in adaptive immunity. The results have implications for the assessment of risks for adverse and persistent immune stimulation following nanoparticle exposures in sensitive populations.
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| 3. |
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| 4. |
- Pollard, Kenneth M, et al.
(författare)
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beta 2-microglobulin is required for the full expression of xenobiotic-induced systemic autoimmunity
- 2011
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Ingår i: JOURNAL OF IMMUNOTOXICOLOGY. - : Informa Healthcare. - 1547-691X. ; 8:3, s. 228-237
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Tidskriftsartikel (refereegranskat)abstract
- ercury exposure in both humans and mice is associated with features of systemic autoimmunity. Murine HgCl(2)-induced autoimmunity (mHgIA) requires MHC Class II, CD4(+) T-cells, co-stimulatory molecules, and interferon-gamma (IFN-gamma), similar to spontaneous models of systemic lupus erythematosus (SLE). beta(2)-microglobulin (B2m) is required for functional MHC Class I molecules and the neonatal F(c) receptor (F(c)Rn). Deficiency of B2m in lupus-prone strains is consistently associated with reduced IgG levels, but with variable effects on other manifestations. Herein, we examined the role of B2m in mHgIA and show that in the absence of B2m, mercury-exposed mice failed to exhibit hypergammaglobulinemia, had reduced anti-nucleolar autoantibodies (ANoA), and had a lower incidence of immune complex deposits in splenic blood vessels, whereas IgG anti-chromatin autoantibodies and renal immune deposits were largely unaffected. Subclass analysis of the IgG anti-chromatin, however, revealed a significant reduction in the IgG(1) subtype. Examination of IFN gamma, IL-4, and IL-2 in exposed skin, draining lymph nodes, and spleen following mercury exposure showed reduced IL-4 in the spleen and skin in B2m-deficient mice, consistent with the lower IgG(1) anti-chromatin levels, and reduced IFN-gamma expression in the skin. These findings demonstrate how a single genetic alteration can partially but significantly modify the clinical manifestations of systemic autoimmunity induced by exposure to xenobiotics.
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| 5. |
- Roser, Luise A., et al.
(författare)
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IL-2-mediated hepatotoxicity : knowledge gap identification based on the irAOP concept
- 2024
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Ingår i: Journal of Immunotoxicology. - 1547-691X. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- Drug-induced hepatotoxicity constitutes a major reason for non-approval and post-marketing withdrawal of pharmaceuticals. In many cases, preclinical models lack predictive capacity for hepatic damage in humans. A vital concern is the integration of immune system effects in preclinical safety assessment. The immune-related Adverse Outcome Pathway (irAOP) approach, which is applied within the Immune Safety Avatar (imSAVAR) consortium, presents a novel method to understand and predict immune-mediated adverse events elicited by pharmaceuticals and thus targets this issue. It aims to dissect the molecular mechanisms involved and identify key players in drug-induced side effects. As irAOPs are still in their infancy, there is a need for a model irAOP to validate the suitability of this tool. For this purpose, we developed a hepatotoxicity-based model irAOP for recombinant human IL-2 (aldesleukin). Besides producing durable therapeutic responses against renal cell carcinoma and metastatic melanoma, the boosted immune activation upon IL-2 treatment elicits liver damage. The availability of extensive data regarding IL-2 allows both the generation of a comprehensive putative irAOP and to validate the predictability of the irAOP with clinical data. Moreover, IL-2, as one of the first cancer immunotherapeutics on the market, is a blueprint for various biological and novel treatment regimens that are under investigation today. This review provides a guideline for further irAOP-directed research in immune-mediated hepatotoxicity.
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| 6. |
- Sakellariou, Christina, et al.
(författare)
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Fine tuning of the innate and adaptive immune responses by Interleukin-2
- 2024
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Ingår i: Journal of Immunotoxicology. - 1547-691X. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- Novel immunotherapies for cancer and other diseases aim to trigger the immune system to produce durable responses, while overcoming the immunosuppression that may contribute to disease severity, and in parallel considering immunosafety aspects. Interleukin-2 (IL-2) was one of the first cytokines that the FDA approved as a cancer-targeting immunotherapy. However, in the past years, IL-2 immunotherapy is not actively offered to patients, due to limited efficacy, when compared to other novel immunotherapies, and the associated severe adverse events. In order to design improved in vitro and in vivo models, able to predict the efficacy and safety of novel IL-2 alternatives, it is important to delineate the mechanistic immunological events triggered by IL-2. Particularly, in this review we will discuss the effects IL-2 has with the bridging cell type of the innate and adaptive immune responses, dendritic cells. The pathways involved in the regulation of IL-2 by dendritic cells and T-cells in cancer and autoimmune disease will also be explored.
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