Enhancing radiotherapy response via intratumoral injection of a TLR9 agonist in autochthonous murine sarcomas.

Radiation therapy (RT) is frequently used to treat cancers, including soft-tissue sarcomas. Prior studies established that the toll-like receptor 9 (TLR9) agonist cytosine-phosphate-guanine oligodeoxynucleotide (CpG) enhances the response to RT in transplanted tumors, but the mechanisms of this enhancement remain unclear. Here, we used CRISPR/Cas9 and the chemical carcinogen 3-methylcholanthrene (MCA) to generate autochthonous soft-tissue sarcomas with high tumor mutation burden. Treatment with a single fraction of 20 Gy RT and 2 doses of CpG significantly enhanced tumor response, which was abrogated by genetic or immunodepletion of CD8+ T cells. To characterize the immune response to CpG+RT, we performed bulk RNA-Seq, single-cell RNA-Seq, and mass cytometry. Sarcomas treated with 20 Gy and CpG demonstrated increased CD8 T cells expressing markers associated with activation and proliferation, such as Granzyme B, Ki-67, and IFN-γ. CpG+RT also upregulated antigen presentation pathways on myeloid cells. Furthermore, in sarcomas treated with CpG+RT, TCR clonality analysis suggests an increase in clonal T cell dominance. Collectively, these findings demonstrate that CpG+RT significantly delays tumor growth in a CD8 T cell-dependent manner. These results provide a strong rationale for clinical trials evaluating CpG or other TLR9 agonists with RT in patients with soft-tissue sarcoma.

Creation of a predictive calculator to determine adequacy of occlusion of the woven endobridge (WEB) device in intracranial aneurysms-A retrospective analysis of the WorldWide WEB Consortium database.

BACKGROUND: Endovascular treatment with the woven endobridge (WEB) device has been widely utilized for managing intracranial aneurysms. However, predicting the probability of achieving adequate occlusion (Raymond-Roy classification 1 or 2) remains challenging. OBJECTIVE: Our study sought to develop and validate a predictive calculator for adequate occlusion using the WEB device via data from a large multi-institutional retrospective cohort. METHODS: We used data from the WorldWide WEB Consortium, encompassing 356 patients from 30 centers across North America, South America, and Europe. Bivariate and multivariate regression analyses were performed on a variety of demographic and clinical factors, from which predictive factors were selected. Calibration and validation were conducted, with variance inflation factor (VIF) parameters checked for collinearity. RESULTS: A total of 356 patients were included: 124 (34.8%) were male, 108 (30.3%) were elderly (≥65 years), and 118 (33.1%) were current smokers. Mean maximum aneurysm diameter was 7.09 mm (SD 2.71), with 112 (31.5%) having a daughter sac. In the multivariate regression, increasing aneurysm neck size (OR 0.706 [95% CI: 0.535-0.929], p = 0.13) and partial aneurysm thrombosis (OR 0.135 [95% CI: 0.024-0.681], p = 0.016) were found to be the only statistically significant variables associated with poorer likelihood of achieving occlusion. The predictive calculator shows a c-statistic of 0.744. Hosmer-Lemeshow goodness-of-fit test indicated a satisfactory model fit with a p-value of 0.431. The calculator is available at: https://neurodx.shinyapps.io/WEBDEVICE/. CONCLUSION: The predictive calculator offers a substantial contribution to the clinical toolkit for estimating the likelihood of adequate intracranial aneurysm occlusion by WEB device embolization.

A chemoenzymatic method for simultaneous profiling N- and O-glycans on glycoproteins using one-pot format.

Glycosylation is generally characterized and controlled as a critical quality attribute for therapeutic glycoproteins because glycans can impact protein drug-product efficacy, half-life, stability, and safety. Analytical procedures to characterize N-glycans are relatively well established, but the characterization of O-glycans is challenging due to the complex workflows and lack of enzymatic tools. Here, we present a simplified chemoenzymatic method to simultaneously profile N- and O-glycans from the same sample using a one-pot format by mass spectrometry (MS). N-glycans were first released by PNGase F, followed by O-glycopeptide generation by proteinase K, selective N-glycan reduction, and O-glycan release by ß-elimination during permethylation of both N- and O-glycans. Glycan structural assignments and determination of N- to O-glycan ratio was obtained from the one-pot mass spectra. The streamlined, one-pot method is a reliable approach that will facilitate advanced characterizations for quality assessments of therapeutic glycoproteins.

Predictors of Aneurysm Obliteration in Patients Treated with the WEB Device: Results of a Multicenter Retrospective Study.

BACKGROUND AND PURPOSE: Despite the numerous studies evaluating the occlusion rates of aneurysms following WEB embolization, there are limited studies identifying predictors of occlusion. Our purpose was to identify predictors of aneurysm occlusion and the need for retreatment. MATERIALS AND METHODS: This is a review of a prospectively maintained database across 30 academic institutions. We included patients with previously untreated cerebral aneurysms embolized using the WEB who had available intraprocedural data and long-term follow-up. RESULTS: We studied 763 patients with a mean age of 59.9 (SD, 11.7) years. Complete aneurysm occlusion was observed in 212/726 (29.2%) cases, and contrast stasis was observed in 485/537 (90.3%) of nonoccluded aneurysms. At the final follow-up, complete occlusion was achieved in 497/763 (65.1%) patients, and retreatment was required for 56/763 (7.3%) patients. On multivariable analysis, history of smoking, maximal aneurysm diameter, and the presence of an aneurysm wall branch were negative predictors of complete occlusion (OR, 0.5, 0.8, and 0.4, respectively). Maximal aneurysm diameter, the presence of an aneurysm wall branch, posterior circulation location, and male sex increase the chances of retreatment (OR, 1.2, 3.8, 3.0, and 2.3 respectively). Intraprocedural occlusion resulted in a 3-fold increase in the long-term occlusion rate and a 5-fold decrease in the retreatment rate (P < .001), offering a specificity of 87% and a positive predictive value of 85% for long-term occlusion. CONCLUSIONS: Intraprocedural occlusion can be used to predict the chance of long-term aneurysm occlusion and the need for retreatment after embolization with a WEB device. Smoking, aneurysm size, and the presence of an aneurysm wall branch are associated with decreased chances of successful treatment.

Improving sustainability of a patient decision aid for systemic treatment of metastatic colorectal cancer: A qualitative study.

Objective: To improve sustainability of a patient decision aid for systemic treatment of metastatic colorectal cancer, we evaluated real-world experiences and identified ways to optimize decision aid content and future implementation. Methods: Semi-structured interviews with patients and medical oncologists addressed two main subjects: user experience and decision aid content. Content analysis was applied. Fifteen experts discussed the results and devised improvements based on experience and literature review. Results: Thirteen users were interviewed. They confirmed the relevance of the decision aid for shared decision making. Areas for improvement of content concerned; 1) outdated and missing information, 2) an imbalance in presentation of treatment benefits and harms, and 3) medical oncologists' expressed preference for a more center-specific or patient individualized decision aid, presenting a selection of the guideline recommended treatment options. Key points for improvement of implementation were better alignment within the care pathway, and clear instruction to users. Conclusion: We identified relevant opportunities for improvement of an existing decision aid and developed an updated version and accompanying implementation strategy accordingly. Innovation: This paper outlines an approach for continued decision aid and implementation strategy development which will add to sustainability. Implementation success of the improved decision aid is currently being studied in a multi-center mixed-methods implementation study.

Multi-phosphine-chelated iron-carbide clusters via redox-promoted ligand exchange on an inert hexa-iron-carbide carbonyl cluster, [Fe6(µ6-C)(µ2-CO)4(CO)12]2.

We report the reactivity, structures and spectroscopic characterization of reactions of phosphine-based ligands (mono-, di- and tri-dentate) with iron-carbide carbonyl clusters. Historically, the archetype of this cluster class, namely [Fe6(µ6-C)(µ2-CO)4(CO)12]2-, can be prepared on a gram-scale but is resistant to simple ligand substitution reactions. This limitation has precluded the relevance of iron-carbide clusters relating to organometallics, catalysis and the nitrogenase active site cluster. Herein, we aimed to derive a simple and reliable method to accomplish CO → L (where L = phosphine or other general ligands) substitution reactions without harsh reagents or multi-step synthetic strategies. Ultimately, our goal was ligand-based chelation of an Fe n (µ n -C) core to achieve more synthetic control over multi-iron-carbide motifs relevant to the nitrogenase active site. We report that the key intermediate is the PSEPT-non-conforming cluster [Fe6(µ6-C)(CO)16] (2: 84 electrons), which can be generated in situ by the outer-sphere oxidation of [Fe6(µ6-C)(CO)16]2- (1: closo, 86 electrons) with 2 equiv. of [Fc]PF6. The reaction of 2 with excess PPh3 generates a singly substituted neutral cluster [Fe5(µ5-C)(CO)14PPh3] (4), similar to the reported reactivity of the substitutionally active cluster [Fe5(µ5-C)(CO)15] with monodentate phosphines (Cooke & Mays, 1990). In contrast, the reaction of 2 with flexible, bidentate phosphines (DPPE and DPPP) generates a wide range of unisolable products. However, the rigid bidentate phosphine bis(diphenylphosphino)benzene (bdpb) disproportionates the cluster into non-ligated Fe3-carbide anions paired with a bdpb-supported Fe(ii) cation, which co-crystallize in [Fe3(µ3-CH)(µ3-CO)(CO)9]2[Fe(MeCN)2(bdpb)2] (6). A successful reaction of 2 with the tripodal ligand Triphos generates the first multi-iron-chelated, authentic carbide cluster of the formula [Fe4(µ4-C)(κ3-Triphos)(CO)10] (9). DFT analysis of the key (oxidized) intermediate 2 suggests that its (µ6-C)Fe6 framework remains fully intact but is distorted into an axially compressed, 'ruffled' octahedron distinct from the parent closo cluster 1. Oxidation of the cluster in non-coordinating solvent allows for the isolation and crystallization of the CO-saturated, intact closo-analogue [Fe6(µ6-C)(CO)17] (3), indicating that the intact (µ6-C)Fe6 motif is retained during initial oxidation with [Fc]PF6. Overall, we demonstrate that redox modulation beneficially 'bends' Wade-Mingo's rules via the generation of electron-starved (non-PSEPT) intermediates, which are the key intermediates in promoting facile CO → L substitution reactions in iron-carbide-carbonyl clusters.

Surface-Charge Tuned Polymeric Nanoemulsions for Carvacrol Delivery in Interkingdom Biofilms.

Biofilms, intricate microbial communities entrenched in extracellular polymeric substance (EPS) matrices, pose formidable challenges in infectious disease treatment, especially in the context of interkingdom biofilms prevalent in the oral environment. This study investigates the potential of carvacrol-loaded biodegradable nanoemulsions (NEs) with systematically varied surface charges─cationic guanidinium (GMT-NE) and anionic carboxylate (CMT-NE). Zeta potentials of +25 mV (GMT-NE) and -33 mV (CMT-NE) underscore successful nanoemulsion fabrication (∼250 nm). Fluorescent labeling and dynamic tracking across three dimensions expose GMT-NE's superior diffusion into oral biofilms, yielding a robust antimicrobial effect with 99.99% killing for both streptococcal and Candida species and marked reductions in bacterial cell viability compared to CMT-NE (∼4-log reduction). Oral mucosa tissue cultures affirm the biocompatibility of both NEs with no morphological or structural changes, showcasing their potential for combating intractable biofilm infections in oral environment. This study advances our understanding of NE surface charges and their interactions within interkingdom biofilms, providing insights crucial for addressing complex infections involving bacteria and fungi in the demanding oral context.

Treatment of large intracranial aneurysms using the Woven EndoBridge (WEB): a propensity score-matched analysis.

The Woven EndoBridge (WEB) device is primarily used for treating wide-neck intracranial bifurcation aneurysms under 10 mm. Limited data exists on its efficacy for large aneurysms. We aim to assess angiographic and clinical outcomes of the WEB device in treating large versus small aneurysms. We conducted a retrospective review of the WorldWide WEB Consortium database, from 2011 to 2022, across 30 academic institutions globally. Propensity score matching (PSM) was employed to compare small and large aneurysms on baseline characteristics. A total of 898 patients were included. There was no significant difference observed in clinical presentations, smoking status, pretreatment mRS, presence of multiple aneurysms, bifurcation location, or prior treatment between the two groups. After PSM, 302 matched pairs showed significantly lower last follow-up adequate occlusion rates (81% vs 90%, p = 0.006) and higher retreatment rates (12% vs 3.6%, p < 0.001) in the large aneurysm group. These findings may inform treatment decisions and patient counseling. Future studies are needed to further explore this area.

Radiomics-Based Predictive Nomogram for Assessing the Risk of Intracranial Aneurysms.

Aneurysm wall enhancement (AWE) has the potential to be used as an imaging biomarker for the risk stratification of intracranial aneurysms (IAs). Radiomics provides a refined approach to quantify and further characterize AWE's textural features. This study examines the performance of AWE quantification combined with clinical information in detecting symptomatic IAs. Ninety patients harboring 104 IAs (29 symptomatic and 75 asymptomatic) underwent high-resolution magnetic resonance imaging (HR-MRI). The assessment of AWE was performed using two different methods: 3D-AWE mapping and composite radiomics-based score (RadScore). The dataset was split into training and testing subsets. The testing set was used to build two different nomograms using each modality of AWE assessment combined with patients' clinical information and aneurysm morphological data. Finally, each nomogram was evaluated on an independent testing set. A total of 22 radiomic features were significantly different between symptomatic and asymptomatic IAs. The 3D-AWE mapping nomogram achieved an area under the curve (AUC) of 0.77 (63% accuracy, 78% sensitivity, and 58% specificity). The RadScore nomogram exhibited a better performance, achieving an AUC of 0.83 (77% accuracy, 89% sensitivity, and 73% specificity). The comprehensive analysis of IAs with the quantification of AWE data through radiomic analysis, patient clinical information, and morphological aneurysm metrics achieves a high accuracy in detecting symptomatic IA status.

Efficacy of intra-arterial carboplatin and bevacizumab in the C6 rat glioma model of glioblastoma multiforme.

BACKGROUND: Utilizing an endovascular rat glioma model, this study aimed to analyze the efficacy of intra-arterial (IA) carboplatin and bevacizumab delivery with blood-brain barrier breakdown (BBBB) for glioblastoma treatment. METHODS: C6-glioma cells were stereotactically injected into the left frontal lobe of Wistar rats. Tumor growth was confirmed on day 8 via MRI. On day 9, a microcatheter was navigated under fluoroscopy from the left femoral artery to the left internal carotid artery. A volume of 2.25 mL of 25% mannitol was administered, followed by either 10 mg/kg of bevacizumab or 2.4 mg/kg of carboplatin. Serial MRI was obtained post-treatment to assess tumor response via analysis of tumor size and radiomics. Histology was analyzed after termination. RESULTS: Control tumor rats and IA mannitol treated tumor rats had fatal tumor growths, with survival until 19.75±2.21 and 36.3±15.1 days, respectively. Carboplatin and bevacizumab treated rats lived >40 days, after which they were euthanized. From serial MRI and histology, IA carboplatin treated rats exhibited tumor regression and resolution by day 35. In IA bevacizumab treated rats, there was tumor regression near the basal ganglia of the brain, closer to the IA chemotherapy injection site, which had reorganized growth patterns. From MRI, 29 unique radiomic features were significantly different between control and treated tumors (notably for total energy and skewness), and treatment responders had a distinct, early manifesting radiomic profile. CONCLUSION: IA carboplatin and bevacizumab treatment resulted in varying degrees of tumor suppression, validating the first endovascular C6 glioma model as a reliable method to assess new IA therapies.

NAD deficiency contributes to progressive kidney disease in HIV-nephropathy mice.

HIV disease remains prevalent in the United States and is particularly prevalent in sub-Saharan Africa. Recent investigations revealed that mitochondrial dysfunction in kidney contributes to HIV-associated nephropathy (HIVAN) in Tg26 transgenic mice. We hypothesized that nicotinamide adenine dinucleotide (NAD) deficiency contributes to energetic dysfunction and progressive tubular injury. We investigated metabolomic mechanisms of HIVAN tubulopathy. Tg26 and wild-type (WT) mice were treated with the farnesoid X receptor (FXR) agonist INT-747 or nicotinamide riboside (NR) from 6 to 12 wk of age. Multiomic approaches were used to characterize kidney tissue transcriptomes and metabolomes. Treatment with INT-747 or NR ameliorated kidney tubular injury, as shown by serum creatinine, the tubular injury marker urinary neutrophil-associated lipocalin, and tubular morphometry. Integrated analysis of metabolomic and transcriptomic measurements showed that NAD levels and production were globally downregulated in Tg26 mouse kidneys, especially nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD salvage pathway. Furthermore, NAD-dependent deacetylase sirtuin3 activity and mitochondrial oxidative phosphorylation activity were lower in ex vivo proximal tubules from Tg26 mouse kidneys compared with those of WT mice. Restoration of NAD levels in the kidney improved these abnormalities. These data suggest that NAD deficiency might be a treatable target for HIVAN.NEW & NOTEWORTHY The study describes a novel investigation that identified nicotinamide adenine dinucleotide (NAD) deficiency in a widely used HIV-associated nephropathy (HIVAN) transgenic mouse model. We show that INT-747, a farnesoid X receptor agonist, and nicotinamide riboside (NR), a precursor of nicotinamide, each ameliorated HIVAN tubulopathy. Multiomic analysis of mouse kidneys revealed that NAD deficiency was an upstream metabolomic mechanism contributing to HIVAN tubulopathy.

Volumetric computed tomography measurements as predictors for outcomes in a cohort of Fournier's gangrene patients.

PURPOSE: This study evaluates the prognostic value of CT findings, including volumetric measurements, in predicting outcomes for patients with Fournier gangrene (FG), focusing on mortality, ICU admission, hospital stay length, and healthcare costs. METHODS: A retrospective study was conducted on 38 FG patients who underwent CT scans before surgical debridement. We analyzed demographic data, CT volumetric measurements, and clinical outcomes using logistic and linear regression models. RESULTS: No single CT measurement significantly predicted mortality or ICU admission. The best model for mortality prediction included age, air volume, NSTI score, and male sex, with an AUC of 0.911. Intubation likelihood was modeled with an AUC of 0.913 using age, NSTI score, and visceral to subcutaneous fat ratio. The ICU admission model achieved an AUC of 0.677. Hospital stay was predicted by air volume (ß = 0.0002656, p = 0.0505) with an adjusted R-squared of 0.1287. Air volume significantly predicted hospital costs (ß = 2.859, p = 0.00558), resulting in an adjusted R-squared of 0.2165. CONCLUSION: Volumetric CT findings provide valuable prognostic insights for FG patients, suggesting a basis for informed clinical decisions and resource allocation. Further validation in larger, multi-center studies is recommended to develop robust predictive models for FG outcomes.

Hybrid Clot Histomic-Transcriptomic Models Predict Functional Outcome After Mechanical Thrombectomy in Acute Ischemic Stroke.

BACKGROUND AND OBJECTIVES: Histologic and transcriptomic analyses of retrieved stroke clots have identified features associated with patient outcomes. Previous studies have demonstrated the predictive capacity of histology or expression features in isolation. Few studies, however, have investigated how paired histologic image features and expression patterns from the retrieved clots can improve understanding of clot pathobiology and our ability to predict long-term prognosis. We hypothesized that computational models trained using clot histomics and mRNA expression can predict early neurological improvement (ENI) and 90-day functional outcome (modified Rankin Scale Score, mRS) better than models developed using histological composition or expression data alone. METHODS: We performed paired histological and transcriptomic analysis of 32 stroke clots. ENI was defined as a delta-National Institutes of Health Stroke Score/Scale > 4, and a good long-term outcome was defined as mRS ≤2 at 90 days after procedure. Clots were H&E-stained and whole-slide imaged at 40×. An established digital pathology pipeline was used to extract 237 histomic features and to compute clot percent composition (%Comp). When dichotomized by either the ENI or mRS thresholds, differentially expressed genes were identified as those with absolute fold-change >1.5 and q < 0.05. Machine learning with recursive feature elimination (RFE) was used to select clot features and evaluate computational models for outcome prognostication. RESULTS: For ENI, RFE identified 9 optimal histologic and transcriptomic features for the hybrid model, which achieved an accuracy of 90.8% (area under the curve [AUC] = 0.98 ± 0.08) in testing and outperformed models based on histomics (AUC = 0.94 ± 0.09), transcriptomics (AUC = 0.86 ± 0.16), or %Comp (AUC = 0.70 ± 0.15) alone. For mRS, RFE identified 7 optimal histomic and transcriptomic features for the hybrid model. This model achieved an accuracy of 93.7% (AUC = 0.94 ± 0.09) in testing, also outperforming models based on histomics (AUC = 0.90 ± 0.11), transcriptomics (AUC = 0.55 ± 0.27), or %Comp (AUC = 0.58 ± 0.16) alone. CONCLUSION: Hybrid models offer improved outcome prognostication for patients with stroke. Identified digital histology and mRNA signatures warrant further investigation as biomarkers of patient functional outcome after thrombectomy.

Development of the Cardiac Conduction System.

The electrical impulses that coordinate the sequential, rhythmic contractions of the atria and ventricles are initiated and tightly regulated by the specialized tissues of the cardiac conduction system. In the mature heart, these impulses are generated by the pacemaker cardiomyocytes of the sinoatrial node, propagated through the atria to the atrioventricular node where they are delayed and then rapidly propagated to the atrioventricular bundle, right and left bundle branches, and finally, the peripheral ventricular conduction system. Each of these specialized components arise by complex patterning events during embryonic development. This chapter addresses the origins and transcriptional networks and signaling pathways that drive the development and maintain the function of the cardiac conduction system.

Imaging of Intracranial Aneurysms: A Review of Standard and Advanced Imaging Techniques.

The treatment of intracranial aneurysms is dictated by its risk of rupture in the future. Several clinical and radiological risk factors for aneurysm rupture have been described and incorporated into prediction models. Despite the recent technological advancements in aneurysm imaging, linear length and visible irregularity with a bleb are the only radiological measure used in clinical prediction models. The purpose of this article is to summarize both the standard imaging techniques, including their limitations, and the advanced techniques being used experimentally to image aneurysms. It is expected that as our understanding of advanced techniques improves, and their ability to predict clinical events is demonstrated, they become an increasingly routine part of aneurysm assessment. It is important that neurovascular specialists understand the spectrum of imaging techniques available.

Structural and functional characterization of IgG- and non-IgG-based T-cell-engaging bispecific antibodies.

Bispecific T-cell-engaging antibodies are a growing class of therapeutics with numerous molecules being tested in clinical trials and, currently, seven of them have received market approval. They are structurally complex and function as adaptors to redirect the cytotoxicity of T cells to kill tumor cells. T-cell-engaging bispecific antibodies can be generally divided into two categories: IgG/IgG-like and non-IgG-like formats. Different formats may have different intrinsic potencies and physiochemical properties, and comprehensive studies are needed to gain a better understanding of how the differences in formats impact on structural and functional characteristics. In this study, we designed and generated bispecific T-cell-engaging antibodies with IgG-like (DVD-Ig) and non-IgG (BiTE) formats. Both target the same pair of antigens (EGFR and CD3) to minimize the possible influence of targets on functional characterization. We performed a side-by-side comparison to assess differences in the physiochemical and biological properties of these two bispecific T-cell-engaging antibodies using a variety of breast and ovarian cancer cell-based functional assays to delineate the structural-functional relationships and anti-tumor activities/potency. We found that the Fc portion of T-cell-engaging bispecific antibodies can significantly impact antigen binding activity, potency, and stability in addition to eliciting different mechanisms of action that contribute the killing of cancer cells.

The Impact of Natriuretic Peptides on Heart Development, Homeostasis, and Disease.

During mammalian heart development, the clustered genes encoding peptide hormones, Natriuretic Peptide A (NPPA; ANP) and B (NPPB; BNP), are transcriptionally co-regulated and co-expressed predominately in the atrial and ventricular trabecular cardiomyocytes. After birth, expression of NPPA and a natural antisense transcript NPPA-AS1 becomes restricted to the atrial cardiomyocytes. Both NPPA and NPPB are induced by cardiac stress and serve as markers for cardiovascular dysfunction or injury. NPPB gene products are extensively used as diagnostic and prognostic biomarkers for various cardiovascular disorders. Membrane-localized guanylyl cyclase receptors on many cell types throughout the body mediate the signaling of the natriuretic peptide ligands through the generation of intracellular cGMP, which interacts with and modulates the activity of cGMP-activated kinase and other enzymes and ion channels. The natriuretic peptide system plays a fundamental role in cardio-renal homeostasis, and its potent diuretic and vasodilatory effects provide compensatory mechanisms in cardiac pathophysiological conditions and heart failure. In addition, both peptides, but also CNP, have important intracardiac actions during heart development and homeostasis independent of the systemic functions. Exploration of the intracardiac functions may provide new leads for the therapeutic utility of natriuretic peptide-mediated signaling in heart diseases and rhythm disorders. Here, we review recent insights into the regulation of expression and intracardiac functions of NPPA and NPPB during heart development, homeostasis, and disease.

Suborgan Level Quantitation of Proteins in Tissues Delivered by Polymeric Nanocarriers.

Amidst the rapid growth of protein therapeutics as a drug class, there is an increased focus on designing systems to effectively deliver proteins to target organs. Quantitative monitoring of protein distributions in tissues is essential for optimal development of delivery systems; however, existing strategies can have limited accuracy, making it difficult to assess suborgan dosing. Here, we describe a quantitative imaging approach that utilizes metal-coded mass tags and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to quantify the suborgan distributions of proteins in tissues that have been delivered by polymeric nanocarriers. Using this approach, we measure nanomole per gram levels of proteins as delivered by guanidinium-functionalized poly(oxanorborneneimide) (PONI) polymers to various tissues, including the alveolar region of the lung. Due to the multiplexing capability of the LA-ICP-MS imaging, we are also able to simultaneously quantify protein and polymer distributions, obtaining valuable information about the relative excretion pathways of the protein cargo and carrier. This imaging approach will facilitate quantitative correlations between nanocarrier properties and protein cargo biodistributions.