SCOPE: This study shows the effect of bovine milk derived extracellular vesicles (BMEVs) on spontaneous polyarthritis in IL‐1Ra‐deficient mice and collagen‐induced arthritis. METHODS AND RESULTS: ...BMEVs were isolated from semi‐skimmed milk by ultracentrifugation and the particle size was around 100 nm by dynamic light scattering and electron microscopy. BMEVs expressed exosome marker CD63, immunoregulatory microRNA's (miR‐30a, ‐223, ‐92a), and milk‐specific beta‐casein and beta‐lactoglobulin mRNA. In vitro, PKH‐67‐labeled BMEVs were taken up by RAW264.7, splenocytes, and intestinal cells as determined by flow cytometry and confocal microscopy. IL‐1Ra⁻/⁻ mice received BMEVs by daily oral gavage starting at wk 5 till 15 after birth and collagen‐induced arthritis mice via their drinking water starting 1 wk before immunization till day 40. Macroscopically, BMEV treatment delayed the onset of arthritis and histology showed diminished cartilage pathology and bone marrow inflammation in both models. BMEV treatment also reduced the serum levels of MCP‐1 and IL‐6 and their production by splenic cells. BMEV treatment diminished the anticollagen IgG2a levels, which was accompanied by reduced splenic Th1 (Tbet) and Th17 (RORγT) mRNA. CONCLUSION: This is the first report that oral delivery of BMEVs ameliorates experimental arthritis and this warrants further research to determine whether this beneficial effect can be seen in rheumatoid arthritis patients.
Perturbations of the intestinal microbiome have been observed in patients with new-onset and chronic autoimmune inflammatory arthritis. However, it is currently unknown whether these alterations ...precede the development of arthritis or are rather a consequence of disease. Modulation of intestinal microbiota by oral antibiotics or germ-free condition can prevent arthritis in mice. Yet, the therapeutic potential of modulation of the microbiota after the onset of arthritis is not well characterized. We here show that the intestinal microbial community undergoes marked changes in the preclinical phase of collagen induced arthritis (CIA). The abundance of the phylum Bacteroidetes, specifically families S24-7 and Bacteroidaceae was reduced, whereas Firmicutes and Proteobacteria, such as Ruminococcaceae, Lachnospiraceae and Desulfovibrinocaceae, were expanded during the immune-priming phase of arthritis. In addition, we found that the abundance of lamina propria Th17, but not Th1, cells is highly correlated with the severity of arthritis. Elimination of the intestinal microbiota during established arthritis specifically reduced intestinal Th17 cells and attenuated arthritis. These effects were associated with reduced serum amyloid A expression in ileum and synovial tissue. Our observations suggest that intestinal microbiota perturbations precede arthritis, and that modulation of the intestinal microbiota after the onset of arthritis may offer therapeutic opportunities.
In this study, the level of the chemokine CXCL4, which is secreted by plasmacytoid dendritic cells, was elevated in patients with systemic sclerosis and correlated with the presence and progression ...of complications.
Systemic sclerosis (also called scleroderma) is a complex heterogeneous fibrosing autoimmune disorder with an unknown pathogenesis. The way in which its three major pathologic hallmarks — extensive fibrosis, vasculopathy, and immune dysfunction — are interconnected is unknown. Mechanistic understanding is limited, in part, by a lack of animal models and by clinically heterogeneous patient populations.
1
This disorder is classified into two major subtypes on the basis of the extent of cutaneous fibrosis: limited cutaneous and diffuse cutaneous systemic sclerosis.
2
Pulmonary fibrosis and pulmonary arterial hypertension are the two most serious complications — currently the major causes of death among patients . . .
Highlights • Small molecule inhibitors targeting the JAK pathway are a promising new treatment strategy for RA. • The Th17 pathway, including IL-17, IL-21, IL-22, and GM-CSF, offers interesting new ...targets for RA. • Dual cytokine inhibition in RA might increase clinical response.
abstract Importance Accumulating evidence suggests that IL-17 A has broad pathogenic roles in multiple autoimmune and immune-mediated inflammatory diseases, including psoriasis and rheumatoid ...arthritis (RA). The development of new therapies that inhibit IL-17 pathway signaling is of clinical significance. Objectives This review aims to summarize the current preclinical evidence on the role of Th17 cells and IL-17 and related cytokines in immune-mediated disease pathophysiology, with a focus on psoriasis and rheumatoid arthritis, as well as to summarize recent clinical trials in these indications with newly developed IL-17 pathway inhibitors. Methods A systematic literature search was conducted of PubMed using relevant keywords. Studies were assessed according to recent relevance to IL-17-mediated pathophysiology and clinical IL-17 inhibition. Experimental animal models of autoimmune disease and clinical studies that focused on IL-17 pathway inhibitors were included. Results Preclinical studies suggest that IL-17A is an attractive therapeutic target. Several IL-17A inhibitors have advanced into clinical trials, including the anti-IL-17A monoclonal antibodies, secukinumab and ixekizumab, and the anti-17RA monoclonal antibody brodalumab. Each has shown variable and sometimes favorable results in proof-of-concept and phase II clinical trials and is currently undergoing further clinical evaluation in a range of immune-mediated diseases. Conclusion Targeting the IL-17 pathway shows promise as strategy to treat immune-mediated diseases ranging from skin to joints.
Obesity-induced inflammation originating from expanding adipose tissue interferes with insulin sensitivity. Important metabolic effects have been recently attributed to IL-1β and IL-18, two members ...of the IL-1 family of cytokines. Processing of IL-1β and IL-18 requires cleavage by caspase-1, a cysteine protease regulated by a protein complex called the inflammasome. We demonstrate that the inflammasome/caspase-1 governs adipocyte differentiation and insulin sensitivity. Caspase-1 is upregulated during adipocyte differentiation and directs adipocytes toward a more insulin-resistant phenotype. Treatment of differentiating adipocytes with recombinant IL-1β and IL-18, or blocking their effects by inhibitors, reveals that the effects of caspase-1 on adipocyte differentiation are largely conveyed by IL-1β. Caspase-1 and IL-1β activity in adipose tissue is increased both in diet-induced and genetically induced obese animal models. Conversely, mice deficient in caspase-1 are more insulin sensitive as compared to wild-type animals. In addition, differentiation of preadipocytes isolated from
caspase-1
−/− or
NLRP3
−/− mice resulted in more metabolically active fat cells. In vivo, treatment of obese mice with a caspase-1 inhibitor significantly increases their insulin sensitivity. Indirect calorimetry analysis revealed higher fat oxidation rates in
caspase-1
−/− animals. In conclusion, the inflammasome is an important regulator of adipocyte function and insulin sensitivity, and caspase-1 inhibition may represent a novel therapeutic target in clinical conditions associated with obesity and insulin resistance.
► The cysteine protease caspase-1 activates proinflammatory cytokines including IL-1β ► Caspase-1 is present in adipose tissue and is a regulator of adipogenesis ► Caspase-1 is activated in adipose tissue of obese and insulin-resistant animals ► Inhibition of caspase-1 in obese animals improves insulin sensitivity
The discovery of interleukin (IL)-17 and its major cell source, the type 17 T-helper (TH17) lymphocyte, has been a major step in the understanding of erosive arthritis. This Review summarizes current ...knowledge of the role of IL-17 in this context derived from both animal models and studies in patients with rheumatoid arthritis. Evidence shows that IL-17 is present at sites of inflammatory arthritis and that, in synergistic interactions, it amplifies the inflammation induced by other cytokines, primarily tumor necrosis factor. In several animal models of arthritis, inhibition of IL-17 limits inflammation and joint erosion. Initial observations from phase I trials show that signs and symptoms of RA are significantly suppressed following treatment with anti-IL-17 antibodies, without notable adverse effects. The emergence of IL-17 blockade as a future therapy in rheumatoid arthritis is highlighted, along with the potential goals and limitations of this therapeutic approach.
Objective
S100A8 and S100A9 are two Ca2+ binding proteins classified as damage‐associated molecular patterns or alarmins that are found in high amounts in the synovial fluid of osteoarthritis (OA) ...patients. The purpose of this study was to investigate whether S100A8 and/or S100A9 can interact with chondrocytes from OA patients to increase catabolic mediators.
Methods
Using immunohistochemistry, we stained for S100A8 and S100A9 protein, matrix metalloproteinases (MMPs), and a cartilage‐breakdown epitope specific for MMPs (VDIPEN) in cartilage from OA donors. Isolated chondrocytes or explants from OA and non‐OA donors were stimulated with S100A8 and/or S100A9. Messenger RNA and protein levels of MMPs, cytokines, and cartilage matrix molecules were determined with quantitative reverse transcription–polymerase chain reaction and Luminex techniques, respectively. For receptor blocking studies, specific inhibitors for Toll‐like receptor 4 (TLR‐4), receptor for advanced glycation end products (RAGE), and carboxylated glycans were used.
Results
In cartilage from OA patients, the expression of S100A8 and S100A9 protein close to chondrocytes was associated with proteoglycan depletion and expression of MMP‐1, MMP‐3, and VDIPEN. Stimulation of chondrocytes with S100A8 and S100A9 caused a strong up‐regulation of catabolic markers (MMPs 1, 3, 9, and 13, interleukin‐6 IL‐6, IL‐8, and monocyte chemotactic protein 1) and down‐regulation of anabolic markers (aggrecan and type II collagen), thereby favoring cartilage breakdown. Blocking TLR‐4, but not carboxylated glycans or RAGE, inhibited the S100 effect. The catabolic S100 effect was significantly more pronounced in chondrocytes from OA patients as compared to those from non‐OA patients, possibly due to higher TLR‐4 expression.
Conclusion
S100A8 and S100A9 have a catabolic effect on human chondrocytes that is TLR‐4 dependent. OA chondrocytes are more sensitive than normal chondrocytes to S100 stimulation.
Perturbation of commensal intestinal microbiota has been associated with several autoimmune diseases. Mice deficient in interleukin-1 receptor antagonist (Il1rn
mice) spontaneously develop autoimmune ...arthritis and are susceptible to other autoimmune diseases such as psoriasis, diabetes, and encephalomyelitis; however, the mechanisms of increased susceptibility to these autoimmune phenotypes are poorly understood. We investigated the role of interleukin-1 receptor antagonist (IL-1Ra) in regulation of commensal intestinal microbiota, and assessed the involvement of microbiota subsets and innate and adaptive mucosal immune responses that underlie the development of spontaneous arthritis in Il1rn
mice.
Using high-throughput 16S rRNA gene sequencing, we show that IL-1Ra critically maintains the diversity and regulates the composition of intestinal microbiota in mice. IL-1Ra deficiency reduced the intestinal microbial diversity and richness, and caused specific taxonomic alterations characterized by overrepresented Helicobacter and underrepresented Ruminococcus and Prevotella. Notably, the aberrant intestinal microbiota in IL1rn
mice specifically potentiated IL-17 production by intestinal lamina propria (LP) lymphocytes and skewed the LP T cell balance in favor of T helper 17 (Th17) cells, an effect transferable to WT mice by fecal microbiota. Importantly, LP Th17 cell expansion and the development of spontaneous autoimmune arthritis in IL1rn
mice were attenuated under germ-free condition. Selective antibiotic treatment revealed that tobramycin-induced alterations of commensal intestinal microbiota, i.e., reduced Helicobacter, Flexispira, Clostridium, and Dehalobacterium, suppressed arthritis in IL1rn
mice. The arthritis phenotype in IL1rn
mice was previously shown to depend on Toll-like receptor 4 (TLR4). Using the ablation of both IL-1Ra and TLR4, we here show that the aberrations in the IL1rn
microbiota are partly TLR4-dependent. We further identify a role for TLR4 activation in the intestinal lamina propria production of IL-17 and cytokines involved in Th17 differentiation preceding the onset of arthritis.
These findings identify a critical role for IL1Ra in maintaining the natural diversity and composition of intestinal microbiota, and suggest a role for TLR4 in mucosal Th17 cell induction associated with the development of autoimmune disease in mice.
Extracellular vesicles, including exosomes, have been identified in all biological fluids and rediscovered as an important part of the intercellular communication. Breast milk also contains ...extracellular vesicles and the proposed biological function is to enhance the antimicrobial defense in newborns. It is, however, unknown whether extracellular vesicles are still present in commercial milk and, more importantly, whether they retained their bioactivity. Here, we characterize the extracellular vesicles present in semi-skimmed cow milk available for consumers and study their effect on T cells.
Extracellular vesicles from commercial milk were isolated and characterized. Milk-derived extracellular vesicles contained several immunomodulating miRNAs and membrane protein CD63, characteristics of exosomes. In contrast to RAW 267.4 derived extracellular vesicles the milk-derived extracellular vesicles were extremely stable under degrading conditions, including low pH, boiling and freezing. Milk-derived extracellular vesicles were easily taken up by murine macrophages in vitro. Furthermore, we found that they can facilitate T cell differentiation towards the pathogenic Th17 lineage. Using a (CAGA)12-luc reporter assay we showed that these extracellular vesicles carried bioactive TGF-β, and that anti-TGF-β antibodies blocked Th17 differentiation.
Our findings show that commercial milk contains stable extracellular vesicles, including exosomes, and carry immunoregulatory cargo. These data suggest that the extracellular vesicles present in commercial cow milk remains intact in the gastrointestinal tract and exert an immunoregulatory effect.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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