Abstract 420: Exploring the Role of TNFα in TLR4-/NLPR3 Inflammasome-driven Inflammation in Humans

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Matthijs Moerland ◽  
Karen Malone ◽  
Marlous Dillingh ◽  
Wieke Grievink ◽  
Joannes Reijers ◽  
...  

The role of TNFα in the pathogenesis of atherosclerosis is incompletely understood. TNFα blockade reduces the severity of various autoimmune diseases and the often related atherosclerosis. However, excessively released TNFα is only one component of the hyperactive innate immune system in such diseases. To provide more insight into the role of TNFα in the induction of inflammation, we explored the effects of TNFα blockade in human whole blood. TLR4/NLPR3 inflammasome challenges were applied to induce an inflammatory response. For this purpose, whole blood was incubated 4 hours with LPS and aluminium hydroxide (Alhydrogel). TNFα blockade was evaluated in vitro (LPS/Alhydrogel challenge in whole blood of 4 healthy human subjects, +concentration range of adalimumab) and ex vivo (LPS/Alhydrogel challenge in whole blood of 13 healthy human subjects receiving a single subcutaneous (sc) dose of 40 mg adalimumab). Cytokine release was evaluated in culture supernatants. In vitro, TNFα blockade strongly reduced TNFα levels detected; -97±1% at the lowest adalimumab concentration (0.3125 μg/mL). TNFα blockade did not affect LPS/Alhydrogel-induced IL-6, IL-1β and IL-18 release, but reduced IFNγ release; maximally -93±4% at 5 μg/mL adalimumab. A single sc adalimumab dose in healthy subjects reduced LPS/Alhydrogel-induced TNFα levels (maximally -98±1% on day 4, and still -58±59% on day 64; versus baseline). IL-6, IL-1β and IL-8 release were not reduced after anti-TNFα treatment. The effect of TNFα blockade on IFNγ release could not be reliably estimated due to highly variable IFNγ levels, especially between genders (baseline IFNγ levels 1248±1771 and 140±283 pg/mL, males vs females). TNFα is a major inducer of NFκB-driven cytokine gene transcription, but TNFα blocking did not reduce LPS/Alhydrogel-induced release of IL-1β, IL-6, IL-8 or IL-18 by primary human cells. This suggests that primary TLR4- and inflammasome-mediated signalling is sufficient to drive secretion of these cytokines. However, in vitro TNFα blockade did impair IFNγ release. Since IFNγ is a key factor in atherogenesis, exerting both pro- and anti-atherogenic properties, our data warrant further mechanistic investigation of the role of TNFα and anti-TNFα therapies in atherosclerosis.

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 540-540 ◽  
Author(s):  
Alexandra Zanin-Zhorov ◽  
Ryan Flynn ◽  
Leo Luznik ◽  
Angela Panoskaltsis-Mortari ◽  
Du Jing ◽  
...  

Abstract Pro-inflammatory IL-17-producing T cells termed Th17 are actively involved in the pathogenesis of GVHD. The development and function of Th17 cells is dependent on activation of STAT3, RORgt and IRF4 transcription factors. Aberrant activation of Rho-associated kinase 2 (ROCK2) leads to induction of IL-17 and IL-21 secretion via IRF4-dependent mechanism. KD025, is a potent and selective ROCK2 inhibitor, which when given to healthy human subjects down-regulated the ability of T cells to secrete IL-21 and IL-17, but not interferon (IFN)-g, in response to TCR stimulation in vitro (Figure 1). KD025 inhibits STAT3 phosphorylation which supports RORgt, Th17 generation, and IL-21 production. Concurrently, KD025 increases STAT5 phosphorylation and Treg suppressor function in a dose-responsive fashion. KD025 treatment therefore shifts Th17/Treg balance. Th17 cells have been linked to in vivo pro-inflammatory responses, antibody production, and fibrosis. Conversely, Tregs can offset these pathogenic responses. Given the profile of KD025, we tested the effects of this inhibitor on cGVHD pathogenesis in a multi-organ system rodent model of disease that is driven by IL-21 responses and is associated with lung, liver and intestinal fibrosis. We observed that Th17/Rorc deficient T cells are unable to mediate cGVHD pathogenesis. In mice with established cGVHD, therapy was initiated with 30, 100, or 150 mg/kg/dose of KD025 daily from d28-56. Treated mice had a dose dependent decrease in the development of pathogenic pulmonary function as determined by whole body plethysmography (Figure 2) which correlated with a marked reduction of antibody deposition in the lungs of treated mice to levels comparable to non-cGVHD controls. KD025 administration also resulted in a 2-fold decrease in collagen deposition in the lungs of mice treated with the highest dose of KD025. The spleens of mice treated with 150 mg/kg dose of KD025 had a decrease in the frequency of germinal centers compared to the vehicle treated mice. To determine the selective role of STAT3 on T cells, mice were transplanted with wildtype (WT) bone marrow (BM) and WT or inducible STAT3 deficient T cells. In parallel cohorts, the role of STAT3 in BM-derived B cells, precursors of germinal center B cells, was examined using WT vs inducible STAT3 deficient BM cells + WT T cells. We demonstrate here that mice transplanted with inducible STAT3 deficient T cells or BM cells had pulmonary function comparable to the healthy negative controls, suggesting that STAT3 is a potential therapeutic target in both T and B cells is necessary for the development of cGVHD and providing mechanistic insight into how KD025 may ameliorate active cGVHD. Studies are in progress to test KD025 administration in a murine scleroderma model using a minor histocompatibility antigen disparate donor-recipient strain that we have shown to be dependent upon STAT3 expressing donor T cells and a STAT3 inhibitor in both cGVHD models described here. Together, these data demonstrate that KD025 is effective at decreasing STAT3-dependent production of IL-21 and IL-17 and the use of KD025 is a potentially novel therapeutic intervention for the treatment of cGVHD. Fig 1 Oral administration of KD025 down-regulates the IL-17 and IL-21 secretion in human PBMCs upon stimulation ex vivo. Human PBMCs were purified from healthy human subjects before and after oral administration of KD025 at doses 40, 120, 240, 320 and stimulated ex vivo. Cytokine secretion was determined after 48 hours by ELISA. Fig 1. Oral administration of KD025 down-regulates the IL-17 and IL-21 secretion in human PBMCs upon stimulation ex vivo. Human PBMCs were purified from healthy human subjects before and after oral administration of KD025 at doses 40, 120, 240, 320 and stimulated ex vivo. Cytokine secretion was determined after 48 hours by ELISA. Fig 2 KD025 is an effective therapy for established murine cGVHD. Mice were given KD025 (150 mg/kg) d.28-56. PFTs indicate normal resistance, elastance and better compliance. Lung Ig deposition and fibrosis were comparable to BM controls. Fig 2. KD025 is an effective therapy for established murine cGVHD. Mice were given KD025 (150 mg/kg) d.28-56. PFTs indicate normal resistance, elastance and better compliance. Lung Ig deposition and fibrosis were comparable to BM controls. Disclosures No relevant conflicts of interest to declare.


Biorheology ◽  
1987 ◽  
Vol 24 (6) ◽  
pp. 795-801 ◽  
Author(s):  
C.R. Huang ◽  
W.D. Pan ◽  
H.Q. Chen ◽  
A.L. Copley

2003 ◽  
Vol 10 (3) ◽  
pp. 495-497 ◽  
Author(s):  
Evert de Jonge ◽  
Philip W. Friederich ◽  
George P. Vlasuk ◽  
William E. Rote ◽  
Margaretha B. Vroom ◽  
...  

ABSTRACT The activation of coagulation has been shown to contribute to proinflammatory responses in animal and in vitro experiments. Here we report that the activation of coagulation in healthy human subjects by the administration of recombinant factor VIIa also elicits a small but significant increase in the concentrations of interleukin 6 (IL-6) and IL-8 in plasma. This increase was absent when the subjects were pretreated with recombinant nematode anticoagulant protein c2, the inhibitor of tissue factor-factor VIIa.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 756-756
Author(s):  
Simmy Thomas ◽  
Chris E Lawrence ◽  
Vernon Mar ◽  
Hue Kha ◽  
Lena A Basile

Abstract Interleukin-12 (IL-12) has potent immunoregulatory and hematopoietic properties, and exerts significant biological effects on natural killer (NK) cells, inducing IFNγ production and enhancing cytotoxicity. Two distinct NK cell populations correlate with their immunoregulatory functions. Mature CD56dimCD16bright NK cells represent 90% of the NK cells resident in the blood and can exert cytotoxic effects on transformed cells. Cytokine producing immature CD56brightCD16+/- NK cells exist in the blood (10% of total circulating NK cells) but are most prominently located in secondary lymphoid tissues. In the continued clinical development of recombinant human IL-12 (HemaMax™, rHuIL-12), to be used in combination with radiotherapy or chemotherapy for the treatment of cancer patients, we have performed a clinical safety study in healthy human subjects. A single subcutaneous (sc) dose of rHuIL-12 (12μg) was administered to 17 healthy human subjects. Placebo was administered to 5 healthy subjects. Peripheral blood samples were collected before rHuIL-12 administration, and up to Day 14 post administration. Immunophenotyping of blood cell populations was conducted by FACS. rHuIL-12 caused a transient decrease in peripheral blood CD56dimCD16bright NK cells, with a nadir (60% reduction from baseline) reached on Day 2 following rHuIL-12 administration. CD56dimCD16bright NK cell levels returned almost to baseline levels on Day 5. Placebo was without effect. Conversely rHuIL-12 caused an elevation in peripheral blood CD56brightCD16+/- NK cells, particularly between Days 2 and 3 after rHuIL-12 administration, which was sustained until a peak was reached on Day 5 (265% above baseline). Levels returned to baseline by Day 11, while placebo was without effect. rHuIL-12 did not impact the less functional CD56-CD16bright NK cell subset. CD56dimCD16bright NK cells expressing the IL-12 receptor β2 subunit (IL-12Rβ2+) showed a substantial, and transient, decrease in levels on Day 2. The plasma concentration of IFNγ was elevated to a peak over 35 fold above baseline level at 10hr. after rHuIL-12 administration. Human NK cells were negatively selected from highly enriched leukapheresis-derived blood and stimulated in vitro with 10 pM rHuIL-12. After 16hr. incubation these predominantly CD56dimCD16brightNK cells showed enhanced release of IFNγ and the increased killing of K562 cells, a human erythroleukemic cell line, when compared with vehicle controls. qPCR analysis of the human NK cell lysates showed rHuIL-12-induced elevation of CD56 (302%) and IL-12Rβ2 (587%) mRNA, when compared with vehicle controls. rHuIL-12 did not influence CD16 mRNA expression, but did increase the level of CD62L (L selectin, 206%) mRNA. The rapid 60% fall in circulating mature CD56dimCD16bright NK cells after rHuIL-12 administration to healthy human subjects suggests their immediate exit from peripheral blood into the tissue compartments. This could be mediated by the observed increase in NK cell CD62L mRNA expression seen in vitro. The sustained increase in immature CD56brightCD16+/- NK cell levels between Day 3 and 6 suggests their IL-12-induced development from CD34+ hematopoietic progenitor cells. In summary rHuIL-12 administration to healthy human subjects demonstrates differential effects on the two key NK cell populations in peripheral blood, increasing CD56brightCD16+/- NK cell numbers, potentially stimulating IFNγ release from and enhancing the cytotoxicity of the CD56dimCD16bright NK cells, and preparing this population for migration into tissues. rHuIL-12 thus shows excellent potential as an immunotherapeutic and hematopoietic agent for the treatment of cancer patients, by impacting the maturation, activation, immunoregulation, and cytolytic properties of NK cells. Disclosures Thomas: Neumedicines: Employment, Equity Ownership. Lawrence:Neumedicines: Employment, Equity Ownership. Mar:Neumedicines: Employment, Equity Ownership. Kha:Neumedicines: Employment, Equity Ownership. Basile:Neumedicines: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees.


2021 ◽  
Author(s):  
Muhammad N. Aslam ◽  
Shannon D. McClintock ◽  
Mohamed Ali H. Jawad-Makki ◽  
Karsten Knuver ◽  
Haris M. Ahmad ◽  
...  

ABSTRACTThe overall goal of this study was to determine if Aquamin®, a calcium- and magnesium-rich natural product, would alter the expression of proteins involved in growth-regulation, differentiation and barrier formation in the colon. Thirty healthy human subjects were enrolled in a three-arm, 90-day interventional trial in which Aquamin® (provided daily to deliver 800-mg of calcium per day) was compared to calcium alone and placebo. Before and after the 90-day interventional period, colonic biopsies were obtained. Biopsies were evaluated by immunohistology for expression of Ki67 (a proliferation marker) and for CK20 and p21 (differentiation markers). Tandem mass tag-mass spectrometry-based detection was used to assess levels of multiple proteins. As compared to placebo or calcium, Aquamin® reduced the level of Ki67 expression (20%). Neither intervention altered CK20 expression, while a trend toward increased p21 was observed with calcium and Aquamin® (117% and 99% respectively). In the proteomic screen, Aquamin® treatment resulted in many more proteins being upregulated or downregulated (1.5 fold-change with ≤2% false-discovery rate) than placebo. Included among the upregulated proteins were cytokeratins, cell-cell adhesion molecules and components of the basement membrane. Many of the downregulated proteins were those involved in proliferation and nucleic acid metabolism. Calcium alone also altered the expression of many of the same proteins but not to the same extent as Aquamin®. We conclude that daily Aquamin® ingestion alters protein expression profile in the colon that could be beneficial to colonic health. These data warrant additional studies with a larger sample size to validate these findings.Prevention RelevanceA multi-mineral approach reduced proliferation and induced differentiation in ex vivo settings and has been shown to decrease colon polyp incidence in mouse (polyp-prevention) studies. The findings from a 90-day trial in human subjects (presented here) demonstrated improved biomarker-modulation efficacy, warranting to conduct the polyp-prevention trial in at-risk human subjects.


Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 3013
Author(s):  
John A. Bouranis ◽  
Laura M. Beaver ◽  
Jaewoo Choi ◽  
Carmen P. Wong ◽  
Duo Jiang ◽  
...  

Isothiocyanates, such as sulforaphane and iberin, derived from glucosinolates (GLS) in cruciferous vegetables, are known to prevent and suppress cancer development. GLS can also be converted by bacteria to biologically inert nitriles, such as sulforaphane-nitrile (SFN-NIT) and iberin-nitrile (IBN-NIT), but the role of the gut microbiome in this process is relatively undescribed and SFN-NIT excretion in humans is unknown. An ex vivo fecal incubation model with in vitro digested broccoli sprouts and 16S sequencing was utilized to explore the role of the gut microbiome in SFN- and IBN-NIT production. SFN-NIT excretion was measured among human subjects following broccoli sprout consumption. The fecal culture model showed high inter-individual variability in nitrile production and identified two sub-populations of microbial communities among the fecal cultures, which coincided with a differing abundance of nitriles. The Clostridiaceae family was associated with high levels, while individuals with a low abundance of nitriles were more enriched with taxa from the Enterobacteriaceae family. High levels of inter-individual variation in urine SFN-NIT levels were also observed, with peak excretion of SFN-NIT at 24 h post broccoli sprout consumption. These results suggest that nitrile production from broccoli, as opposed to isothiocyanates, could be influenced by gut microbiome composition, potentially lowering efficacy of cruciferous vegetable interventions.


2015 ◽  
Vol 4 ◽  
Author(s):  
P. Ramnani ◽  
A. Costabile ◽  
A. G. R. Bustillo ◽  
G. R. Gibson

AbstractThis placebo-controlled, randomised, double-blind, cross-over human feeding study aimed to determine the prebiotic effect of agave fructans. A total of thirty-eight volunteers completed this trial. The treatment consisted of 3 weeks' supplementation with 5 g/d of prebiotic agave fructan (Predilife) or equivalent placebo (maltodextrin), followed by a 2-week washout period following which subjects were crossed over to alternate the treatment arm for 3 weeks followed by a 2-week washout. Faecal samples were collected at baseline, on the last day of treatment (days 22 and 58) and washout (days 36 and 72), respectively. Changes in faecal bacterial populations, SCFA and secretory IgA were assessed using fluorescentin situhybridisation, GC and ELISA, respectively. Bowel movements, stool consistencies, abdominal comfort and mood changes were evaluated by a recorded daily questionnaire. In parallel, the effect of agave fructans on different regions of the colon using a three-stage continuous culture simulator was studied. Predilife significantly increased faecal bifidobacteria (log109·6 (sd0·4)) and lactobacilli (log107·7 (sd0·8)) compared with placebo (log109·2 (sd0·4);P = 0·00) (log107·4 (sd0·7);P= 0·000), respectively. No change was observed for other bacterial groups tested, SCFA, secretory IgA, and PGE2concentrations between the treatment and placebo. Denaturing gradient gel electrophoresis analysis indicated that bacterial communities were randomly dispersed and no significant differences were observed between Predilife and placebo treatments. Thein vitromodels showed similar increases in bifidobacterial and lactobacilli populations to that observed with thein vivotrial. To conclude, agave fructans are well tolerated in healthy human subjects and increased bifidobacteria and lactobacilli numbersin vitroandin vivobut did not influence other products of fermentation.


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