The most frequent subtype of acute myeloid leukemia (AML) is defined by mutations in the nucleophosmin 1 (NPM1) gene. Mutated NPM1 (ΔNPM1) is an attractive target for immunotherapy, since it is an ...essential driver gene and 4 bp frameshift insertions occur in the same hotspot in 30%-35% of AMLs, resulting in a C-terminal alternative reading frame of 11 aa. By searching the HLA class I ligandome of primary AMLs, we identified multiple ΔNPM1-derived peptides. For one of these peptides, HLA-A*02:01-binding CLAVEEVSL, we searched for specific T cells in healthy individuals using peptide-HLA tetramers. Tetramer-positive CD8+ T cells were isolated and analyzed for reactivity against primary AMLs. From one clone with superior antitumor reactivity, we isolated the T cell receptor (TCR) and demonstrated specific recognition and lysis of HLA-A*02:01-positive ΔNPM1 AML after retroviral transfer to CD8+ and CD4+ T cells. Antitumor efficacy of TCR-transduced T cells was confirmed in immunodeficient mice engrafted with a human AML cell line expressing ΔNPM1. In conclusion, the data show that ΔNPM1-derived peptides are presented on AML and that CLAVEEVSL is a neoantigen that can be efficiently targeted on AML by ΔNPM1 TCR gene transfer. Immunotherapy targeting ΔNPM1 may therefore contribute to treatment of AML.
Genetic P300/CBP-associated factor (PCAF) variation affects restenosis-risk in patients. PCAF has lysine acetyltransferase activity and promotes nuclear factor kappa-beta (NFκB)-mediated ...inflammation, which drives post-interventional intimal hyperplasia development. We studied the contributing role of PCAF in post-interventional intimal hyperplasia.
PCAF contribution to inflammation and intimal hyperplasia was assessed in leukocytes, macrophages and vascular smooth muscle cells (vSMCs) in vitro and in a mouse model for intimal hyperplasia, in which a cuff is placed around the femoral artery. PCAF deficiency downregulate CCL2, IL-6 and TNF-alpha expression, as demonstrated on cultured vSMCs, leukocytes and macrophages. PCAF KO mice showed a 71.8% reduction of vSMC-rich intimal hyperplasia, a 73.4% reduction of intima/media ratio and a 63.7% reduction of luminal stenosis after femoral artery cuff placement compared to wild type (WT) mice. The association of PCAF and vascular inflammation was further investigated using the potent natural PCAF inhibitor garcinol. Garcinol treatment reduced CCL2 and TNF-alpha expression, as demonstrated on cultured vSMCs and leukocytes. To assess the effect of garcinol treatment on vascular inflammation we used hypercholesterolemic ApoE*3-Leiden mice. After cuff placement, garcinol treatment resulted in reduced arterial leukocyte and macrophage adherence and infiltration after three days compared to untreated animals.
These results identify a vital role for the lysine acetyltransferase PCAF in the regulation of local inflammation after arterial injury and likely the subsequent vSMC proliferation, responsible for intimal hyperplasia.
Effective neovascularization is crucial for recovery after cardiovascular events.
Because microRNAs regulate expression of up to several hundred target genes, we set out to identify microRNAs that ...target genes in all pathways of the multifactorial neovascularization process. Using www.targetscan.org, we performed a reverse target prediction analysis on a set of 197 genes involved in neovascularization. We found enrichment of binding sites for 27 microRNAs in a single microRNA gene cluster. Microarray analyses showed upregulation of 14q32 microRNAs during neovascularization in mice after single femoral artery ligation.
Gene silencing oligonucleotides (GSOs) were used to inhibit 4 14q32 microRNAs, miR-329, miR-487b, miR-494, and miR-495, 1 day before double femoral artery ligation. Blood flow recovery was followed by laser Doppler perfusion imaging. All 4 GSOs clearly improved blood flow recovery after ischemia. Mice treated with GSO-495 or GSO-329 showed increased perfusion already after 3 days (30% perfusion versus 15% in control), and those treated with GSO-329 showed a full recovery of perfusion after 7 days (versus 60% in control). Increased collateral artery diameters (arteriogenesis) were observed in adductor muscles of GSO-treated mice, as well as increased capillary densities (angiogenesis) in the ischemic soleus muscle. In vitro, treatment with GSOs led to increased sprout formation and increased arterial endothelial cell proliferation, as well as to increased arterial myofibroblast proliferation.
The 14q32 microRNA gene cluster is highly involved in neovascularization. Inhibition of 14q32 microRNAs miR-329, miR-487b, miR-494, and miR-495 provides a promising tool for future therapeutic neovascularization.
Annexin A5 (AnxA5) is known to have anti-inflammatory and anti-apoptotic properties. Inflammation and apoptosis are key processes in post-ischemic cardiac remodeling. In this study, we investigated ...the effect of AnxA5 on left ventricular (LV) function and remodeling three weeks after myocardial ischemia-reperfusion (MI-R) injury in hypercholesterolemic ApoE*3-Leiden mice. Using a mouse model for MI-R injury, we demonstrate AnxA5 treatment resulted in a 27% reduction of contrast-enhanced MRI assessed infarct size (IS). End-diastolic and end-systolic volumes were decreased by 22% and 38%, respectively. LV ejection fraction was increased by 29% in the AnxA5 group compared to vehicle. Following AnxA5 treatment LV fibrous content after three weeks was reduced by 42%, which was accompanied by an increase in LV wall thickness of the infarcted area by 17%. Two days and three weeks after MI-R injury the number of cardiac macrophages was significantly reduced in both the infarct area and border zones following AnxA5 treatment compared to vehicle treatment. Finally, we found that AnxA5 stimulation leads to a reduction of IL-6 production in bone-marrow derived macrophages in vitro. AnxA5 treatment attenuates the post-ischemic inflammatory response and ameliorates LV remodeling which improves cardiac function three weeks after MI-R injury in hypercholesterolemic ApoE*3-Leiden mice.
Background
Phosphorylcholine (PC) is an important pro‐inflammatory damage‐associated molecular pattern. Previous data have shown that natural IgM anti‐PC protects against cardiovascular disease. We ...aimed to develop a monoclonal PC IgG antibody with anti‐inflammatory and anti‐atherosclerotic properties.
Methods
Using various techniques PC antibodies were validated and optimized. In vivo testing was performed in a femoral artery cuff model in ApoE3*Leiden mice. Safety studies are performed in rats and cynomolgus monkeys.
Results
A chimeric anti‐PC (PC‐mAb(T15), consisting of a human IgG1 Fc and a mouse T15/E06 Fab) was produced, and this was shown to bind specifically to epitopes in human atherosclerotic tissues. The cuff model results in rapid induction of inflammatory genes and altered expression of genes associated with ER stress and choline metabolism in the lesions. Treatment with PC‐mAb(T15) reduced accelerated atherosclerosis via reduced expression of endoplasmic reticulum stress markers and CCL2 production. Recombinant anti‐PC Fab fragments were identified by phage display and cloned into fully human IgG1 backbones creating a human monoclonal IgG1 anti‐PC (PC‐mAbs) that specifically bind PC, apoptotic cells and oxLDL. Based on preventing macrophage oxLDL uptake and CCL2 production, four monoclonal PC‐mAbs were selected, which to various extent reduced vascular inflammation and lesion development. Additional optimization and validation of two PC‐mAb antibodies resulted in selection of PC‐mAb X19‐A05, which inhibited accelerated atherosclerosis. Clinical grade production of this antibody (ATH3G10) significantly attenuated vascular inflammation and accelerated atherosclerosis and was tolerated in safety studies in rats and cynomolgus monkeys.
Conclusions
Chimeric anti‐PCs can prevent accelerated atherosclerosis by inhibiting vascular inflammation directly and through reduced macrophage oxLDL uptake resulting in decreased lesions. PC‐mAb represents a novel strategy for cardiovascular disease prevention.
Phosphorylcholine is a pro‐inflammatory epitope exposed on apoptotic cells, and phosphorylcholine monoclonal immunoglobulin (Ig)G antibodies (PC‐mAb) have anti‐inflammatory properties. In this study, ...we hypothesize that PC‐mAb treatment reduces adverse cardiac remodelling and infarct size (IS) following unreperfused transmural myocardial infarction (MI). Unreperfused MI was induced by permanent ligation of the left anterior descending (LAD) coronary artery in hypercholesterolaemic APOE*3‐Leiden mice. Three weeks following MI, cardiac magnetic resonance (CMR) imaging showed a reduced LV end‐diastolic volume (EDV) by 21% and IS by 31% upon PC‐mAb treatment as compared to the vehicle control group. In addition, the LV fibrous content was decreased by 27% and LV wall thickness was better preserved by 47% as determined by histological analysis. Two days following MI, CCL2 concentrations, assessed by use of ELISA, were decreased by 81% and circulating monocytes by 64% as assessed by use of FACS analysis. Additionally, local leucocyte infiltration determined by immunohistological analysis showed a 62% decrease after three weeks. In conclusion, the local and systemic inflammatory responses are limited by PC‐mAb treatment resulting in restricted adverse cardiac remodelling and IS following unreperfused MI. This indicates that PC‐mAb holds promise as a therapeutic agent following MI limiting adverse cardiac remodelling.
Our study assessed whether rising age, socioeconomic status (SES) and the presence of serious comorbidity affected treatment choice and survival in a population‐based series of patients with ...muscle‐invasive bladder cancer (MIBC) in The Netherlands. Therefore, a consecutive series was studied, including all patients diagnosed with MIBC between 1995 and 2009 in the Eindhoven Cancer Registry, preceding centralization of cystectomy. The independent effects of age, SES and serious comorbidity on therapy choice and their effects on overall survival were estimated by multivariate logistic regression and multivariate Cox proportional hazard analyses, respectively. Out of the 2,445 patients, 38% were aged ≥75 years at diagnosis and 63% had at least one serious comorbid condition. Higher age and serious comorbidity were independent predictors for abstaining from cystectomy, where SES was not (61–74 vs. ≤60: odds ratio OR, 0.8; 95% confidence interval CI, 0.6–1.0; ≥75 vs. ≤60: OR, 0.1; 95% CI,0.1–0.2; one comorbid condition vs. none: OR, 0.7; 95% CI, 0.5–0.9; two vs. none: OR, 0.6; 95% CI, 0.5–0.8). Patients undergoing cystectomy, external beam radiotherapy or interstitial radiotherapy survived longer independent of age, SES and serious comorbidity (hazard ratio HR: 0.4; 95% CI: 0.4–0.5; HR: 0.8; 95% CI: 0.7–0.9; HR: 0.4; 95% CI: 0.3–0.5, respectively). Consequently, preceding centralization of cystectomy, higher age and serious comorbidity were independent predictors for abstaining from cystectomy owing to an expected high rate of short‐term medical problems. As cystectomy is associated with a better survival, independently of age, SES and serious comorbidity, it can be questioned whether cystectomy has been underutilised in elderly and in patients with serious comorbidity. Centralization might be a solution for this suggested underutilisation.
What's new?
Bladder cancer is a frequent disease in the elderly, but higher age and existence of comorbidities cloud the treatment options in these patients. This population‐based study of a large unselected group of patients with muscle‐invasive bladder cancer shows that cystectomy is associated with a better survival, independently from age, socio‐economic status and serious comorbidities. However, higher age and serious comorbidity were independent predictors for abstaining from cystectomy as shown in this study. Based on their results, the authors raise the question whether cystectomy is underutilized in the elderly and patients with serious comorbidities despite its documented benefit as the preferred treatment option in all patient groups.
To date, only a few randomized clinical trials (RCTs) have investigated the effects of omega-3 fatty acids (FA) on Alzheimer's disease (AD). Some of these studies demonstrated that patients with very ...mild AD or mild cognitive impairment benefit from omega-3 FA treatment, but none showed significant improvements in cognitive function in patients with moderate or advanced AD. All these RCTs had a relatively short duration of supplementation, however, and we hypothesized that this might be one of the reasons why no effects of omega-3 FA supplementation could be observed in patients with "moderate" or "advanced" AD. Animal studies offer better possibilities for controlled long-term supplementation than clinical studies. Therefore, we performed a systematic review (SR) and meta-analysis of the literature that focused on effects of the relatively long-term omega-3 FA supplementation (minimum period; 10% of average total lifespan) on cognitive impairment, amyloid-β pathology, and neuronal loss in animal models of AD. This SR shows that long-term omega-3 FA supplementation decreased the omega-6/omega-3 FA ratio and reduced the amount of amyloid-β in experimental animal models of AD. Omega-3 FA supplementation also improved cognitive function; this effect appeared larger in rats compared to mice, and in males compared to females. Moreover, omega-3 FA supplementation diminished the amount of neuronal loss, especially in female animals. The results of this SR indicate that it might be worthwhile to perform new clinical trials with long-term omega-3 FA supplementation in AD patients.
Phosphorylcholine (PC) is one of the main oxLDL epitopes playing a central role in atherosclerosis, due to its atherogenic and proinflammatory effects. PC can be cleared by natural IgM antibodies and ...low levels of these antibodies have been associated with human vein graft (VG) failure. Although PC antibodies are recognized for their anti-inflammatory properties, their effect on intraplaque angiogenesis (IPA) and intraplaque hemorrhage (IPH)—interdependent processes contributing to plaque rupture—are unknown. We hypothesized that new IgG phosphorylcholine antibodies (PC-mAb) could decrease vulnerable lesions in murine VGs.Therefore, hypercholesterolemic male ApoE3*Leiden mice received a (donor) caval vein interposition in the carotid artery and weekly IP injections of (5 mg/kg) PCmAb (n = 11) or vehicle (n = 12) until sacrifice at day 28. We found that PCmAb significantly decreased vein graft media (13%), intima lesion (25%), and increased lumen with 32% compared to controls. PCmAb increased collagen content (18%) and decreased macrophages presence (31%). PCmAb resulted in 23% decreased CD163+ macrophages content in vein grafts whereas CD163 expression was decreased in Hb:Hp macrophages. PCmAb significantly lowered neovessel density (34%), EC proliferation and migration with/out oxLDL stimulation. Moreover, PCmAb enhanced intraplaque angiogenic vessels maturation by increasing neovessel pericyte coverage in vivo (31%). Together, this resulted in a 62% decrease in IPH. PCmAb effectively inhibits murine atherosclerotic lesion formation in vein grafts by reducing IPA and IPH via decreased neovessel density and macrophages influx and increased neovessel maturation. PC-mAb therefore holds promise as a new therapeutic approach to prevent vein graft disease.
Objective
To elucidate the role of interferon regulatory factor (IRF)3 and IRF7 in neovascularization.
Methods
Unilateral hind limb ischaemia was induced in Irf3−/−, Irf7−/− and C57BL/6 mice by ...ligation of the left common femoral artery. Post‐ischaemic blood flow recovery in the paw was measured with laser Doppler perfusion imaging. Soleus, adductor and gastrocnemius muscles were harvested to investigate angiogenesis and arteriogenesis and inflammation.
Results
Post‐ischaemic blood flow recovery was decreased in Irf3−/− and Irf7−/− mice compared to C57BL/6 mice at all time points up to and including sacrifice, 28 days after surgery (t28). This was supported by a decrease in angiogenesis and arteriogenesis in soleus and adductor muscles of Irf3−/− and Irf7−/− mice at t28. Furthermore, the number of macrophages around arterioles in adductor muscles was decreased in Irf3−/− and Irf7−/− mice at t28. In addition, mRNA expression levels of pro‐inflammatory cytokines (tnfα, il6, ccl2) and growth factor receptor (vegfr2), were decreased in gastrocnemius muscles of Irf3−/− and Irf7−/− mice compared to C57BL/6 mice.
Conclusion
Deficiency of IRF3 and IRF7 results in impaired post‐ischaemic blood flow recovery caused by attenuated angiogenesis and arteriogenesis linked to a lack of inflammatory components in ischaemic tissue. Therefore, IRF3 and IRF7 are essential regulators of neovascularization.
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