Hyperactive Rac stimulates cannibalism of living target cells and enhances CAR-M-mediated cancer cell killing.

The 21kD GTPase Rac is an evolutionarily ancient regulator of cell shape and behavior. Rac2 is predominantly expressed in hematopoietic cells where it is essential for survival and motility. The hyperactivating mutation Rac2E62K also causes human immunodeficiency, although the mechanism remains unexplained. Here, we report that in Drosophila, hyperactivating Rac stimulates ovarian cells to cannibalize neighboring cells, destroying the tissue. We then show that hyperactive Rac2E62K stimulates human HL60-derived macrophage-like cells to engulf and kill living T cell leukemia cells. Primary mouse Rac2+/E62K bone-marrow-derived macrophages also cannibalize primary Rac2+/E62K T cells due to a combination of macrophage hyperactivity and T cell hypersensitivity to engulfment. Additionally, Rac2+/E62K macrophages non-autonomously stimulate wild-type macrophages to engulf T cells. Rac2E62K also enhances engulfment of target cancer cells by chimeric antigen receptor-expressing macrophages (CAR-M) in a CAR-dependent manner. We propose that Rac-mediated cell cannibalism may contribute to Rac2+/E62K human immunodeficiency and enhance CAR-M cancer immunotherapy.

Subnational Projections of Lymphatic Filariasis Elimination Targets in Ethiopia to Support National Level Policy.

BACKGROUND: Lymphatic filariasis (LF) is a debilitating, poverty-promoting, neglected tropical disease (NTD) targeted for worldwide elimination as a public health problem (EPHP) by 2030. Evaluating progress towards this target for national programmes is challenging, due to differences in disease transmission and interventions at the subnational level. Mathematical models can help address these challenges by capturing spatial heterogeneities and evaluating progress towards LF elimination and how different interventions could be leveraged to achieve elimination by 2030. METHODS: Here we used a novel approach to combine historical geo-spatial disease prevalence maps of LF in Ethiopia with 3 contemporary disease transmission models to project trends in infection under different intervention scenarios at subnational level. RESULTS: Our findings show that local context, particularly the coverage of interventions, is an important determinant for the success of control and elimination programmes. Furthermore, although current strategies seem sufficient to achieve LF elimination by 2030, some areas may benefit from the implementation of alternative strategies, such as using enhanced coverage or increased frequency, to accelerate progress towards the 2030 targets. CONCLUSIONS: The combination of geospatial disease prevalence maps of LF with transmission models and intervention histories enables the projection of trends in infection at the subnational level under different control scenarios in Ethiopia. This approach, which adapts transmission models to local settings, may be useful to inform the design of optimal interventions at the subnational level in other LF endemic regions.

An Ensemble Framework for Projecting the Impact of Lymphatic Filariasis Interventions Across Sub-Saharan Africa at a Fine Spatial Scale.

BACKGROUND: Lymphatic filariasis (LF) is a neglected tropical disease targeted for elimination as a public health problem by 2030. Although mass treatments have led to huge reductions in LF prevalence, some countries or regions may find it difficult to achieve elimination by 2030 owing to various factors, including local differences in transmission. Subnational projections of intervention impact are a useful tool in understanding these dynamics, but correctly characterizing their uncertainty is challenging. METHODS: We developed a computationally feasible framework for providing subnational projections for LF across 44 sub-Saharan African countries using ensemble models, guided by historical control data, to allow assessment of the role of subnational heterogeneities in global goal achievement. Projected scenarios include ongoing annual treatment from 2018 to 2030, enhanced coverage, and biannual treatment. RESULTS: Our projections suggest that progress is likely to continue well. However, highly endemic locations currently deploying strategies with the lower World Health Organization recommended coverage (65%) and frequency (annual) are expected to have slow decreases in prevalence. Increasing intervention frequency or coverage can accelerate progress by up to 5 or 6 years, respectively. CONCLUSIONS: While projections based on baseline data have limitations, our methodological advancements provide assessments of potential bottlenecks for the global goals for LF arising from subnational heterogeneities. In particular, areas with high baseline prevalence may face challenges in achieving the 2030 goals, extending the "tail" of interventions. Enhancing intervention frequency and/or coverage will accelerate progress. Our approach facilitates preimplementation assessments of the impact of local interventions and is applicable to other regions and neglected tropical diseases.

Macrophage Ontogeny, Phenotype, and Function in Ischemia Reperfusion-Induced Injury and Repair.

AKI is characterized by a sudden, and usually reversible, decline in kidney function. In mice, ischemia-reperfusion injury (IRI) is commonly used to model the pathophysiologic features of clinical AKI. Macrophages are a unifying feature of IRI as they regulate both the initial injury response as well as the long-term outcome following resolution of injury. Initially, macrophages in the kidney take on a proinflammatory phenotype characterized by the production of inflammatory cytokines, such as CCL2 (monocyte chemoattractant protein 1), IL-6, IL-1 ß , and TNF- α . Release of these proinflammatory cytokines leads to tissue damage. After resolution of the initial injury, macrophages take on a reparative role, aiding in tissue repair and restoration of kidney function. By contrast, failure to resolve the initial injury results in prolonged inflammatory macrophage accumulation and increased kidney damage, fibrosis, and the eventual development of CKD. Despite the extensive amount of literature that has ascribed these functions to M1/M2 macrophages, a recent paradigm shift in the macrophage field now defines macrophages on the basis of their ontological origin, namely monocyte-derived and tissue-resident macrophages. In this review, we focus on macrophage phenotype and function during IRI-induced injury, repair, and transition to CKD using both the classic (M1/M2) and novel (ontological origin) definition of kidney macrophages.

Intra-Articular Injectable Biomaterials for Cartilage Repair and Regeneration.

Osteoarthritis is a degenerative joint disease characterized by cartilage deterioration and subsequent inflammatory changes in the underlying bone. Injectable hydrogels have emerged as a promising approach for controlled drug delivery in cartilage therapies. This review focuses on the latest developments in utilizing injectable hydrogels as vehicles for targeted drug delivery to promote cartilage repair and regeneration. The pathogenesis of osteoarthritis is discussed to provide a comprehensive understanding of the disease progression. Subsequently, the various types of injectable hydrogels used for intra-articular delivery are discussed. Specifically, physically and chemically crosslinked injectable hydrogels are critically analyzed, with an emphasis on their fabrication strategies and their capacity to encapsulate and release therapeutic agents in a controlled manner. Furthermore, the potential of incorporating growth factors, anti-inflammatory drugs, and cells within these injectable hydrogels are discussed. Overall, this review offers a comprehensive guide to navigating the landscape of hydrogel-based therapeutics in osteoarthritis.

Postmortem mitochondria function in longissimus lumborum of Angus and Brahman steers.

Mitochondria function and integrity may impact postmortem metabolism and meat quality development. Adaptations in heat tolerant Brahman may persist to limit cellular stress postmortem. Our objective was to evaluate glycolysis, pH decline, and mitochondria function in longissimus lumborum (LL) from Angus and Brahman steers (N = 28) early postmortem (1 to 6 h) and after rigor (24 h). We evaluated metabolites of anaerobic glycolysis, ATP, pH, and temperature, and determined mitochondria oxygen consumption rate (OCR) in permeabilized fibers. The main effects of breed (b) and time (t) and the interaction were tested. Brahman LL contained greater ATP during the first 6 h postmortem; Brahman also tended to exhibit a slower pH decline (b × t, P = 0.07) and more rapid temperature decline (b × t, P < 0.001), but metabolites of anaerobic glycolysis were not different. Mitochondria in Brahman and Angus LL were well-coupled and respired at 1 h postmortem. However, outer membrane integrity became increasingly compromised postmortem (t, P < 0.001). Brahman tended to exhibit greater electron transport system capacity (b, P < 0.1) and had greater capacity for oxidative phosphorylation (complex I and II substrates) at 6 h compared with Angus (P < 0.001). In totality, greater ATP, slower pH decline, and enhanced mitochondria capacity indicate that Brahman possess mitochondrial properties or cellular adaptations that help protect the cell during energy stress postmortem. Slower pH and more rapid temperature decline in LL from Brahman may also help preserve mitochondria function postmortem.

Protocol for hybrid structured-light three-dimensional scanning and modeling of human postmortem brains.

Despite numerous neuropathological criteria for the evaluation of microscopic tissue slides, there are no systemic standards for sectioning postmortem human brain tissue. Here, we present a protocol for postmortem brain hybrid structured-light scanning to facilitate 3D printing of sectioning matrices. We describe steps for tissue preparation, 3D scanning and printing, and matrix-guided sectioning. This protocol can be used for streamlining tissue histopathology as well as in brain morphology volumetric analyses and applications in medical education. For complete details on the use and execution of this protocol, please refer to Barannikov et al.1.

Determination of psilocybin and psilocin content in multiple Psilocybe cubensis mushroom strains using liquid chromatography - tandem mass spectrometry.

A method for clinical potency determination of psilocybin and psilocin in hallucinogenic mushroom species Psilocybe cubensis was developed using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Five strains of dried, intact mushrooms were obtained and analyzed: Blue Meanie, Creeper, B-Plus, Texas Yellow, and Thai Cubensis. An extraction protocol was developed; this included an evaluation of sample milling technique, extraction solvents, and recovery/stability. Reversed phase chromatography on fused-core particle phases was developed for the determination of the two analytes using internal standard calibration with deuterated isotopologues of each analyte. The separation takes less than 5 min. Matrix effects were investigated by comparing signal response of calibration samples in neat solution and several mushroom matrices; no significant matrix effects were observed. The limit of detection for psilocybin was 1.5 ng/mL (1.5 pg on-column; 300 ng/g mushroom) and for psilocin was 0.15 ng/mL (0.15 pg on-column; 30 ng/g mushroom) using a Shimadzu LCMS-8050 triple quadrupole mass spectrometer. Assessment of the accuracy and precision of the method indicated percent error and RSD were <6 % at all concentration levels. Three whole, intact mushrooms from each strain were analyzed individually to obtain average content differences both between strains and between mushrooms of the same strain. From most to least potent, the study found that the average total psilocybin and psilocin concentrations for the Creeper, Blue Meanie, B+, Texas Yellow, and Thai Cubensis strains were 1.36, 1.221, 1.134, 1.103, and 0.879 % (w/w), respectively. A subset of these mushrooms was also tested in a separate non-affiliated laboratory, and the results were comparable between the two laboratories. Results from the secondary laboratory showed improved precision when multiple mushrooms were homogenized together, prior to extraction.

Peripheral quantitative computed tomography is a valid imaging technique for tracking changes in skeletal muscle cross-sectional area.

Peripheral quantitative computed tomography (pQCT) has recently expanded to quantifying skeletal muscle, however its validity to determine muscle cross-sectional area (mCSA) compared to magnetic resonance imaging (MRI) is unknown. Eleven male participants (age: 22 ± 3 y) underwent pQCT and MRI dual-leg mid-thigh imaging before (PRE) and after (POST) 6 weeks of resistance training for quantification of mid-thigh mCSA and change in mCSA. mCSA agreement at both time points and absolute change in mCSA across time was assessed using Bland-Altman plots for mean bias and 95% limits of agreement (LOA), as well as Lin's concordance correlation coefficients (CCC). Both pQCT and MRI mCSA increased following 6 weeks of resistance training (∆mCSApQCT: 6.7 ± 5.4 cm2, p < 0.001; ∆mCSAMRI: 6.0 ± 6.4 cm2, p < 0.001). Importantly, the change in mCSA was not different between methods (p = 0.39). Bland-Altman analysis revealed a small mean bias (1.10 cm2, LOA: -6.09, 8.29 cm2) where pQCT tended to overestimate mCSA relative to MRI when comparing images at a single time point. Concordance between pQCT and MRI mCSA at PRE and POST was excellent yielding a CCC of 0.982. For detecting changes in mCSA, Bland-Altman analysis revealed excellent agreement between pQCT and MRI (mean bias: -0.73 cm2, LOA: -8.37, 6.91 cm2). Finally, there was excellent concordance between pQCT and MRI mCSA change scores (CCC = 0.779). Relative to MRI, pQCT imaging is a valid technique for measuring both mid-thigh mCSA at a single time point and mCSA changes following a resistance training intervention.