Silencing of CCR2 in myocarditis Leuschner, Florian; Courties, Gabriel; Dutta, Partha ...
European heart journal,
06/2015, Letnik:
36, Številka:
23
Journal Article
Recenzirano
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Myocarditis is characterized by inflammatory cell infiltration of the heart and subsequent deterioration of cardiac function. Monocytes are the most prominent population of accumulating leucocytes. ...We investigated whether in vivo administration of nanoparticle-encapsulated siRNA targeting chemokine (C-C motif) receptor 2 (CCR2)-a chemokine receptor crucial for leucocyte migration in humans and mice--reduces inflammation in autoimmune myocarditis.
In myocardium of patients with myocarditis, CCL2 mRNA levels and CCR2(+) cells increased (P < 0.05), motivating us to pursue CCR2 silencing. Flow cytometric analysis showed that siRNA silencing of CCR2 (siCCR2) reduced the number of Ly6C(high) monocytes in hearts of mice with acute autoimmune myocarditis by 69% (P < 0.05), corroborated by histological assessment. The nanoparticle-delivered siRNA was not only active in monocytes but also in bone marrow haematopoietic progenitor cells. Treatment with siCCR2 reduced the migration of bone marrow granulocyte macrophage progenitors into the blood. Cellular magnetic resonance imaging (MRI) after injection of macrophage-avid magnetic nanoparticles detected myocarditis and therapeutic effects of RNAi non-invasively. Mice with acute myocarditis showed enhanced macrophage MRI contrast, which was prevented by siCCR2 (P < 0.05). Follow-up MRI volumetry revealed that siCCR2 treatment improved ejection fraction (P < 0.05 vs. control siRNA-treated mice).
This study highlights the importance of CCR2 in the pathogenesis of myocarditis. In addition, we show that siCCR2 affects leucocyte progenitor trafficking. The data also point to a novel therapeutic strategy for the treatment of myocarditis.
Rectal adenocarcinoma (READ) constitutes one-third of newly diagnosed colorectal cancer cases. Surgery, chemotherapy and concurrent chemoradiotherapy are the main treatments to improve patient ...outcomes for READ. However, patients with READ receiving these treatments eventually relapse, leading to a poor survival outcome. The present study collected surgical specimens from patients with READ and determined that cytoplasmic cell division cycle 27 (CDC27) expression was associated with the risk of lymph node metastasis and distant metastasis. Nuclear CDC27 expression was negatively associated with 5-year disease-free survival (DFS) and 5-year overall survival (OS) rates. Multivariate Cox proportional regression analysis showed that nuclear CDC27 was an independent prognostic factor in the patients with READ, especially in those treated with adjuvant chemotherapy. High nuclear CDC27 expression was significantly associated with poorer 5-year DFS (HR, 2.106; 95% CI, 1.275-3.570; P=0.003) and 5-year OS (HR, 2.369; 95% CI, 1.270-4.6810; P=0.005) rates. The data indicated that cytoplasmic CDC27 expression could affect tumor progression and that it plays an important role in metastasis. Nuclear CDC27 expression was markedly associated with poorer survival outcomes and was an independent prognostic factor in patients with postoperative adjuvant chemotherapy-treated READ. Thus, CDC27 expression serves as a potential prognostic marker for rectal tumor progression and chemotherapy treatment.
Unbound tissue-to-plasma partition coefficients (Kpuu) were determined for 56 structurally diverse compounds in rats following intravenous infusion. Five tissues were included in the study: white ...adipose, brain, heart, liver, and skeletal muscle. The rank ordering of the median tissue Kpuu values was: liver (4.5) > heart (1.8) > adipose (1.2) > skeletal muscle (0.6) > brain (0.05), with liver being most enriched and brain most impaired. The median Kpuu values of acids and zwitterions were lower than those of bases and neutrals in all tissues but liver. Selective tissue distribution was observed, dependent upon chemotype, which demonstrated the feasibility of targeting or restricting drug exposure in certain tissues through rational design. Physicochemical attributes for Kpuu were identified using recursive partitioning, which further classified compounds with enriched or impaired tissue distribution. The attributes identified provided valuable insight on design principles for asymmetric tissue distribution to improve efficacy or reduce toxicity.
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•Compounds demonstrate unique tissue distributions depending on structural characteristics.•It is feasible to achieve asymmetric tissue distribution through rational medicinal chemistry design.•Enriched tissue exposure has been observed for compounds in all ionization classes.•Transporters not only transport ionizable compounds, but also neutrals.•Liver is the most enriched tissue; brain, most impaired; and heart, most unimpaired.
Importance Perianal fistulizing complications (PFCs) develop in 15% to 30% of patients with Crohn disease (CD), are difficult to treat, worsen quality of life, increase cost of care, and commonly ...recur. Evidence-based strategies to prevent PFCs are lacking. Objectives To investigate the effectiveness of medical therapy for reducing risk of PFCs among young people with CD and to test the hypothesis that steroid-sparing therapy (SST) use would be associated with reduced risk of PFC development. Design, Setting, and Participants In this comparative effectiveness analysis of commercial administrative claims from January 1, 2001, through June 30, 2016, patients who did or did not initiate SST were matched via propensity score to adjust for all available confounders. Using Optum’s Clinformatics Data Mart, a deidentified database of US commercial administrative claims, all patients aged 5 to 24 years with CD (January 1, 2001, through June 30, 2016) were identified. The index date was the CD diagnosis date. Patients with PFCs or SST use at or before CD diagnosis were excluded. The dates of analysis were October 2017 to February 2020. Exposures The primary exposure of interest was SST initiation, including immunomodulators and/or anti–tumor necrosis factor α (anti-TNFα) medications, initiated before either PFC development or the end of the study period. Main Outcomes and Measures The primary outcome was PFC development. Propensity score matching was used to balance baseline characteristics. Cox proportional hazards multivariable regression analyses were used to estimate hazard ratios (HRs) with 95% CIs for PFC development. Results Among 2214 young people with CD without PFCs identified, the mean (SD) age at CD diagnosis was 17.0 (4.5) years, and 1151 (52.0%) were male. Among the cohort, 1242 patients (56.1%) initiated SST before PFC development or the end of 24-month follow-up. After propensity score matching, 972 patients remained in each treatment group. Overall, 384 of 1944 (19.8%) developed PFCs within 2 years of the index date. The use of SST was associated with a 59% decreased risk of PFC development (hazard ratio HR, 0.41; 95% CI, 0.33-0.52;P < .001) in 2 years compared with no SST use. Among those who developed PFCs, 55% fewer SST users underwent ostomy than SST nonusers. The use of immunomodulators alone, anti-TNFα alone, and combination therapy was associated with 52% (HR, 0.48; 95% CI, 0.37-0.62;P < .001), 47% (HR, 0.53; 95% CI, 0.36-0.78;P = .001), and 83% (HR, 0.17; 95% CI, 0.09-0.30;P < .001) reductions in the risk of 2-year PFC development, respectively, compared with no SST use. Conclusions and Relevance In this study, PFC development was common among young patients with CD. The use of SST was lower than expected. Compared with no SST, patients who initiated SST were 59% less likely to develop PFCs and fewer underwent ostomy. These results indicate that PFCs may be preventable and emphasize the importance of considering SST for all patients with CD.
Dendritic cells (DCs) are potent antigen-presenting cells that express FcεRI, the high-affinity IgE receptor. Although the downregulation of basophil FcεRI during anti-IgE therapy with omalizumab is ...well documented, its effect on FcεRI expression by DCs has not been reported.
We hypothesized that IgE regulates surface FcεRI expression by DCs in vivo and that, consequently, anti-IgE therapy decreases FcεRI expression by DCs.
In a randomized, double-blind, placebo-controlled clinical trial 24 subjects (16 receiving omalizumab and 8 receiving placebo) with seasonal allergic rhinitis received the study drug on days 0 and 28. Serial blood samples drawn on days 0, 7, 14, 28, and 42 were analyzed for precursor DC1 (pDC1) and pDC2 surface expression of FcεRIα by using flow cytometry.
Omalizumab caused a significant decrease in surface FcεRI expression at all time points examined in both the pDC1 and pDC2 subsets. No significant change was seen with placebo. The maximum decrease in FcεRI expression in the omalizumab group was 52% and 83%, respectively, for the pDC1 and pDC2 subsets. The decrease in FcεRI expression by both pDC subsets correlated with the decrease in serum-free IgE and was of a similar magnitude to that found in basophils. A 10-fold decrease in IgE corresponded to a 42% and 54% decrease in surface FcεRI expression by the pDC1 and pDC2 subsets, respectively.
These results demonstrate that anti-IgE therapy causes a rapid decrease in DC surface FcεRI expression and establish that IgE is an important regulator of FcεRI expression by DCs.
Solid tumors are dense three-dimensional (3D) multicellular structures that enable efficient receptor-ligand trans interactions via close cell-cell contact. Immunoglobulin-like transcript (ILT)2 and ...ILT4 are related immune-suppressive receptors that play a role in the inhibition of myeloid cells within the tumor microenvironment. The relative contribution of ILT2 and ILT4 to immune inhibition in the context of solid tumor tissue has not been fully explored. We present evidence that both ILT2 and ILT4 contribute to myeloid inhibition. We found that although ILT2 inhibits myeloid cell activation in the context of trans-engagement by MHC-I, ILT4 efficiently inhibits myeloid cells in the presence of either cis- or trans-engagement. In a 3D spheroid tumor model, dual ILT2/ILT4 blockade was required for the optimal activation of myeloid cells, including the secretion of CXCL9 and CCL5, upregulation of CD86 on dendritic cells, and downregulation of CD163 on macrophages. Humanized mouse tumor models showed increased immune activation and cytolytic T-cell activity with combined ILT2 and ILT4 blockade, including evidence of the generation of immune niches, which have been shown to correlate with clinical response to immune-checkpoint blockade. In a human tumor explant histoculture system, dual ILT2/ILT4 blockade increased CXCL9 secretion, downregulated CD163 expression, and increased the expression of M1 macrophage, IFNγ, and cytolytic T-cell gene signatures. Thus, we have revealed distinct contributions of ILT2 and ILT4 to myeloid cell biology and provide proof-of-concept data supporting the combined blockade of ILT2 and ILT4 to therapeutically induce optimal myeloid cell reprogramming in the tumor microenvironment.
A simple, efficient, and scalable manufacturing technique is required for developing siRNA-lipid nanoparticles (siRNA-LNP) for therapeutic applications. In this chapter we describe a novel ...microfluidic-based manufacturing process for the rapid manufacture of siRNA-LNP, together with protocols for characterizing the size, polydispersity, RNA encapsulation efficiency, RNA concentration, and total lipid concentration of the resultant nanoparticles.
Treatment of chronic myeloid leukemia with a tyrosine kinase inhibitor (TKI) offers significant improvements over previous treatments in terms of survival and toxicity yet nevertheless is associated ...with reduced health-related quality of life and very high cost. Several small studies from Europe and Australia suggested that discontinuing TKIs with regular monitoring was safe.
The Life After Stopping TKIs (LAST) study is a large, U.S.-based study that aims to improve the evidence for clinical decision making regarding TKI discontinuation with monitoring in patients with chronic myeloid leukemia who have a deep molecular response to TKI therapy. The LAST study is a non-randomized, prospective, single-group longitudinal study of 173 patients. The co-primary objectives are to determine the proportion of patients who develop molecular recurrence (> 0.1% BCR-ABL
) after discontinuing one of four TKIs (imatinib, dasatinib, nilotinib, or bosutinib) and to compare the patient-reported health status of patients before and after stopping TKIs. Outcomes are assessed at baseline and throughout the 36-month study follow-up period with a central laboratory used for blood samples. All samples with undetectable BCR-ABL are also examined using digital polymerase chain reaction, which is a more sensitive nanofluidic polymerase chain reaction system.
Because of their high cost and side effects, discontinuation of TKIs for patients with chronic myeloid leukemia who have a deep molecular response to TKI therapy is a promising approach to treatment. The LAST study is the largest U.S.-based TKI discontinuation study. It is the first to allow participation from patients on any of 4 first- and second-generation TKIs, includes a robust approach to measurement of clinical and patient-reported outcomes, and is using digital polymerase chain reaction to explore better prediction of safe discontinuation.
This study was registered prospectively on October 21, 2014 and assigned trial number NCT02269267 .
Eukaryotic genome stability is maintained by a complex and diverse set of molecular processes. One class of enzymes that promotes proper DNA repair, replication and cell cycle progression comprises ...small ubiquitin-like modifier (SUMO)-targeted E3 ligases, or STUbLs. Previously, we reported a role for the budding yeast STUbL synthetically lethal with sgs1 (Slx) 5/8 in preventing G2/M-phase arrest in a minichromosome maintenance protein 10 (Mcm10)-deficient model of replication stress. Here, we extend these studies to human cells, examining the requirement for the human STUbL RING finger protein 4 (RNF4) in MCM10 mutant cancer cells. We find that MCM10 and RNF4 independently promote origin firing but regulate DNA synthesis epistatically and, unlike in yeast, the negative genetic interaction between RNF4 and MCM10 causes cells to accumulate in G1-phase. When MCM10 is deficient, RNF4 prevents excessive DNA under-replication at hard-to-replicate regions that results in large DNA copy number alterations and severely reduced viability. Overall, our findings highlight that STUbLs participate in species-specific mechanisms to maintain genome stability, and that human RNF4 is required for origin activation in the presence of chronic replication stress.
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•It is unknown if human MCM10 and RNF4 genetically interact like in budding yeast.•MCM10/RNF4 genetic interaction causes severe replicative stress in HCT116 cells.•MCM10 and RNF4 separately promote origin firing but together control DNA synthesis.•RNF4 loss exacerbates large chromosomal changes driven by MCM10 deficiency.•STUbLs promote eukaryotic genome stability via organism specific mechanisms.
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