Background and Purpose
Rho kinase (ROCK) activation is involved in neuroinflammatory processes leading to progression of neurodegenerative diseases such as Parkinson's disease. Furthermore, ROCK ...plays a major role in angiogenesis. Neuroinflammation and angiogenesis are mechanisms involved in developing l‐DOPA‐induced dyskinesias (LID). However, it is not known whether ROCK plays a role in LID and whether ROCK inhibitors may be useful against LID.
Experimental Approach
In rats, we performed short‐ and long‐term dopaminergic lesions using 6‐hydroxydopamine and developed a LID model. Effects of dopaminergic lesions and LID on the RhoA/ROCK levels were studied by western blot, real‐time PCR analyses and ROCK activity assays in the substantia nigra and striatum. The effects of the ROCK inhibitor fasudil on LID were particularly investigated.
Key Results
Short‐term 6‐hydroxydopamine lesions increased nigrostriatal RhoA/ROCK expression, apparently related to the active neuroinflammatory process. However, long‐term dopaminergic denervation (completed and stabilized lesions) led to a decrease in RhoA/ROCK levels. Rats with LID showed a significant increase of RhoA and ROCK expression. The development of LID was reduced by the ROCK inhibitor fasudil (10 and 40 mg·kg−1), without interfering with the therapeutic effect of l‐DOPA. Interestingly, treatment of 40 mg·kg−1 of fasudil also induced a significant reduction of dyskinesia in rats with previously established LID.
Conclusion and Implications
The present results suggest that ROCK is involved in the pathophysiology of LID and that ROCK inhibitors such as fasudil may be a novel target for preventing or treating LID. Furthermore, previous studies have revealed neuroprotective effects of ROCK inhibitors.
Chimeric antigen receptor (CAR) T cells provide great efficacy in B cell malignancies. However, improved CAR T cell therapies are still needed. Here, we engineered tumor-targeted CAR T cells to ...constitutively express the immune-stimulatory molecule CD40 ligand (CD40L) and explored efficacy in different mouse leukemia/lymphoma models. We observed that CD40L+ CAR T cells circumvent tumor immune escape via antigen loss through CD40/CD40L-mediated cytotoxicity and induction of a sustained, endogenous immune response. After adoptive cell transfer, the CD40L+ CAR T cells displayed superior antitumor efficacy, licensed antigen-presenting cells, enhanced recruitment of immune effectors, and mobilized endogenous tumor-recognizing T cells. These effects were absent in Cd40−/− mice and provide a rationale for the use of CD40L+ CAR T cells in cancer treatment.
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•CD40L+ CAR T cells kill antigen-negative tumor cells through CD40/CD40L interactions•CD40L+ CAR T cells improve antitumor response compared with second-generation CAR T cells•CD40L+ CAR T cells license APCs in vivo to aid in antitumor response•Licensed APCs prime non-CAR T cells to recognize tumor cells and produce cytokines
Kuhn et al. engineer tumor-targeted CAR T cells to constitutively express CD40L. Through direct CD40/CD40L-mediated cytotoxicity and indirect induction of an immune response by enhancing recruitment and activation of immune effectors, the CD40L+ CAR T cells overcome tumor immune escape via antigen loss.
Patients with small cell lung cancer (SCLC) generally have a poor prognosis and a median overall survival of only about 13 months, indicating the urgent need for novel therapies. Delta-like protein 3 ...(DLL3) has been identified as a tumor-specific cell surface marker on neuroendocrine cancers, including SCLC. In this study, we developed a chimeric antigen receptor (CAR) against DLL3 that displays antitumor efficacy in xenograft and murine SCLC models. CAR T cell expression of the proinflammatory cytokine IL-18 greatly enhanced the potency of DLL3-targeting CAR T cell therapy. In a murine metastatic SCLC model, IL-18 production increased the activation of both CAR T cells and endogenous tumor-infiltrating lymphocytes. We also observed an increased infiltration, repolarization, and activation of antigen-presenting cells. Additionally, human IL-18-secreting anti-DLL3 CAR T cells showed an increased memory phenotype, less exhaustion, and induced durable responses in multiple SCLC models, an effect that could be further enhanced with anti-PD-1 blockade. All together, these results define DLL3-targeting CAR T cells that produce IL-18 as a potentially promising novel strategy against DLL3-expressing solid tumors.
Plasmodium actins form very short filaments and have a noncanonical link between ATP hydrolysis and polymerization. Long filaments are detrimental to the parasites, but the structural factors ...constraining Plasmodium microfilament lengths have remained unknown. Using high-resolution crystallography, we show that magnesium binding causes a slight flattening of the Plasmodium actin I monomer, and subsequent phosphate release results in a more twisted conformation. Thus, the Mg-bound monomer is closer in conformation to filamentous (F) actin than the Ca form, and this likely facilitates polymerization. A coordinated potassium ion resides in the active site during hydrolysis and leaves together with the phosphate, a process governed by the position of the Arg178/Asp180-containing A loop. Asp180 interacts with either Lys270 or His74, depending on the protonation state of the histidine, while Arg178 links the inner and outer domains (ID and OD) of the actin protomer. Hence, the A loop acts as a switch between stable and unstable filament conformations, the latter leading to fragmentation. Our data provide a comprehensive model for polymerization, ATP hydrolysis and phosphate release, and fragmentation of parasite microfilaments. Similar mechanisms may well exist in canonical actins, although fragmentation is much less favorable due to several subtle sequence differences as well as the methylation of His73, which is absent on the corresponding His74 in Plasmodium actin I.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Malaria is responsible for half a million deaths annually and poses a huge economic burden on the developing world. The mosquito-borne parasites (Plasmodium spp.) that cause the disease depend upon ...an unconventional actomyosin motor for both gliding motility and host cell invasion. The motor system, often referred to as the glideosome complex, remains to be understood in molecular terms and is an attractive target for new drugs that might block the infection pathway. Here, we present the high-resolution structure of the actomyosin motor complex from Plasmodium falciparum. The complex includes the malaria parasite actin filament (PfAct1) complexed with the class XIV myosin motor (PfMyoA) and its two associated light-chains. The high-resolution core structure reveals the PfAct1:PfMyoA interface in atomic detail, while at lower-resolution, we visualize the PfMyoA light-chain binding region, including the essential light chain (PfELC) and the myosin tail interacting protein (PfMTIP). Finally, we report a bare PfAct1 filament structure at improved resolution.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Extraction protocols and liquid chromatography coupled with mass spectrometry (LC–MS) and tandem mass spectrometry (LC–MS/MS) methods for the measurement of four lipid categories, namely ...glycerophospholipids, glycerolipids, sphingolipids and sterol lipids in human plasma, are described here. Step‐by‐step instructions are provided for the liquid–liquid extraction methods, including solution preparation and the non‐endogenous lipid internal standards used. All instrumental conditions, chromatography columns and solutions required for the LC–MS and LC–MS/MS methods are also provided in detail.
BACKGROUND:Pancreatic exocrine insufficiency (PEI) is a common serious complication in chronic pancreatitis (CP); however, little is known about its effect on mortality in these patients. In this ...study, we assessed the mortality risk of PEI in patients with CP.
STUDY:A prospective, longitudinal cohort study conducted in patients with CP under long-term follow-up. CP and PEI were diagnosed using pancreatic imaging and the C-labeled mixed triglyceride breath test, respectively. Multivariate analysis was performed to evaluate the impact of PEI and other clinical features on mortality risk.
RESULTS:Patients (N=430) were analyzed (79.1% male; mean age, 47.8 y) during a mean follow-up of 8.6±4.6 years. PEI prevalence was 29.3% and mortality was 10.9%. Most frequent causes of death were cancer (40.4%), infection (21.3%), and acute cardiovascular event (14.9%). Multivariate analyses showed associations between increased mortality and presence of PEI hazard ratio (HR), 2.59; 95% confidence interval (CI), 1.42-4.71; P<0.003, liver cirrhosis (HR, 3.87; 95% CI, 1.95-7.69; P<0.001), age at diagnosis (HR, 1.05; 95% CI, 1.03-1.09; P<0.001), toxic etiology of CP (HR, 3.11; 95% CI, 1.11-8.70; P<0.05) and respiratory comorbidity (HR, 2.19; 95% CI, 1.12-4.31; P<0.03). Nutritional markers were significantly lower in patients with PEI versus those without PEI (P<0.001) and in those who died versus survivors (P<0.001).
CONCLUSIONS:PEI was a significant independent risk factor for mortality in patients with CP. These results support further research into the optimal treatment of PEI to reduce mortality in this population.
A novel haplotype composed of two non‐coding variants, CYP2C18 NM_000772.3:c.*31T (rs2860840) and NM_000772.2:c.819+2182G (rs11188059), referred to as “CYP2C:TG,” was recently associated with ...ultrarapid metabolism of various CYP2C19 substrates. As the underlying mechanism and clinical relevance of this effect remain uncertain, we analyzed existing in vivo and in vitro data to determine the magnitude of the CYP2C:TG haplotype effect. We assessed variability in pharmacokinetics of CYP2C19 substrates, including citalopram, sertraline, voriconazole, omeprazole, pantoprazole, and rabeprazole in 222 healthy volunteers receiving one of these six drugs. We also determined its impact on CYP2C8, CYP2C9, CYP2C18, and CYP2C19 protein abundance in 135 human liver tissue samples, and on CYP2C18/CYP2C19 activity in vitro using N‐desmethyl atomoxetine formation. No effects were observed according to CYP2C:TG haplotype or to CYP2C19*1+TG alleles (i.e., CYP2C19 alleles containing the CYP2C:TG haplotype). In contrast, CYP2C19 intermediate (e.g., CYP2C19*1/*2) and poor metabolizers (e.g., CYP2C19*2/*2) showed significantly higher exposure in vivo, lower CYP2C19 protein abundance in human liver microsomes, and lower activity in vitro compared with normal, rapid (i.e., CYP2C19*1/*17), and ultrarapid metabolizers (i.e., CYP2C19*17/*17). Moreover, a tendency toward lower exposure was observed in ultrarapid metabolizers compared with rapid metabolizers and normal metabolizers. Furthermore, when the CYP2C19*17 allele was present, CYP2C18 protein abundance was increased suggesting that genetic variation in CYP2C19 may be relevant to the overall metabolism of certain drugs by regulating not only its expression levels, but also those of CYP2C18. Considering all available data, we conclude that there is insufficient evidence supporting clinical CYP2C:TG testing to inform drug therapy.
CAR T-cell therapy for multiple myeloma (MM) targeting B-cell maturation antigen (
; BCMA) induces high overall response rates; however, relapse occurs commonly. Implicated in relapse is a reservoir ...of MM if cells lacking sufficient BCMA surface expression (antigen escape). We demonstrate that simultaneous targeting of an additional antigen-here, G protein-coupled receptor class-C group-5 member-D (
)-can prevent BCMA escape-mediated relapse in a model of MM. To identify an optimal approach, we compare subtherapeutic doses of different forms of dual-targeted cellular therapy. These include (1) parallel-produced and pooled mono-targeted CAR T-cells, (2) bicistronic constructs expressing distinct CARs from a single vector, and (3) a dual-scFv "single-stalk" CAR design. When targeting BCMA-negative disease, bicistronic and pooled approaches had the highest efficacy, whereas for dual-antigen-expressing disease, the bicistronic approach was more efficacious than the pooled approach. Mechanistically, expressing two CARs on a single cell enhanced the strength of CAR T-cell/target cell interactions.
Chimeric antigen receptor (CAR) T-cell therapy has shown remarkable responses in B-cell malignancies. However, many patients suffer from limited response and tumor relapse due to lack of persisting ...CAR T cells and immune escape. These clinical challenges have compromised the long-term efficacy of CAR T-cell therapy and call for the development of novel CAR designs. We demonstrated that CAR T cells secreting a cytokine interleukin-36γ (IL-36γ) showed significantly improved CAR T-cell expansion and persistence, and resulted in superior tumor eradication compared with conventional CAR T cells. The enhanced cellular function by IL-36γ was mediated through an autocrine manner. In addition, activation of endogenous antigen-presenting cells (APCs) and T cells by IL-36γ aided the formation of a secondary antitumor response, which delayed the progression of antigen-negative tumor challenge. Together, our data provide preclinical evidence to support the translation of this design for an improved CAR T-cell-mediated antitumor response.
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