Faculty Bibliography

BACKGROUND:in healthy Caucasian non-Hispanic individuals. METHODS:is achieved, additional HF-LED-RL phototherapy subjects and mock therapy subjects will be enrolled at that fluence (group 3) for a total number of up to 60 subjects. Each subject will receive a total of nine irradiation sessions, three times per week for three consecutive weeks. DISCUSSION/CONCLUSIONS:in Caucasian non-Hispanic subjects. The importance of this clinical trial is that it may establish new treatment paradigms and a safety profile for LED-RL based on race and ethnicity. TRIAL REGISTRATION/BACKGROUND:ClinicalTrials.gov Identifier: NCT03433222 . Registered on February 1, 2018 - Retrospectively registered. Protocol date and version: January 12, 2018; version 1.

Purpose: Many studies have been shown that obesity along with joint injury is one of the most common risk factor in the development of osteoarthritis (OA). In a previous study we described that intra-articular injections of liposomal preparations of adenosine completely prevent progression and reverse cartilage loss in post-traumatic OA. TGF-beta signaling plays dual and opposing roles in cartilage health and chondrocyte life depending on the signals activated downstream. Activation of downstream signaling pathways for TGF-beta leading to localization of phospho-SMAD2/3 associated with maintenance of cartilage. In contrast nuclear localization of phospho-SMAD1/5/8 results in chondrocyte hypertrophy. Here we report that intraarticular injections of liposomal adenosine and A2AR agonist reverses OA in a post-traumatic OA model in rat and in an obesity related mice model. We moreover explore the role of TGF-beta signaling in this phenomenon. Method(s): Obesity-induced OA model: C57Bl6 mice (5-6 for each group, 12 weeks old) were fed a 60% fat diet (HFF mice) for 3months, after which received intraarticular injections (10 mul) of empty liposomes (Lipo) or liposomes containing the A2AR agonist CGS21680 (Lipo-CGS) or Adenosine (Lipo-Ado) into the knee every 10 days for 4 injections. Post-traumatic OA (PTOA) was induced in Sprague Dawley rats following non-surgical rupture of anterior cruciate ligament (ACL). Four weeks later rats were injected in the knee with 100ul of saline, Lipo or Lipo-CGS every 10 days (6 injections). RNA was isolated from chondrocytes in knee cartilage of rats treated as described above (3 from each group X 3 replicates) and subjected to RNAseq analysis. TC28a2 human chondrocyte cell line was used for in vitro experiments. Result(s): Lipo-CGS and Lipo-Ado reversed OA in the obesity and post traumatic OA model. Mouse knees had an OARSI score of 5.17+/-1.84 before treatment. Treatment with LIPO-Ado and lipo-CGS decreased OA severity (OARSI score 1.33+/-0.81 and 1.83+/-0.98, respectively, p<0.001 vs pre-treatment; figure 1). In the PTOA model the OARSI score significantly decreases after Lipo-CGS and Lipo-Ado treatment compare to the saline group (OARSI: 1.28+/-0.39; 1.42+/-0.69; 2.97+/-0.0.75 respectively; p<0.05). Analysis of the transcriptome suggests that the treatment of Lipo-CGS promotes the up-regulation of genes involved in proliferation process and downregulations of genes responsible of apoptosis, cartilage catabolism and chondrocyte hypertrophy (Figure 2). TGF-beta expression was increased in deep layers of cartilage in the Lipo-CGS-treated rats and there was notable nuclear localization of phospho-SMAD2/3 in these chondrocytes. In contrast, phospho-SMAD1/5/8 was expressed in the nuclei of chondrocytes in the saline and LIPO-treated rats but not in the LIPO-CGS treated rats. Identical changes were observed in the knees of obese mice. To determine whether the effect of A2AR stimulation on TGF-beta signaling was direct or indirect we studied the effect of CGS21680 on nuclear phospho-SMAD expression in TC28a2 cells and found that CGS21680 increased nuclear phospho-SMAD2/3 and reduced nuclear phospho-SMAD1/5/8, as detected by immunofluorescence. Conclusion(s): Administration of an A2AR agonist to established OA knees reverses OA in rats and mice and shifts TGF-beta signaling from ALK1/SMAD1/5/8 to ALK5/SMAD2/3 in OA chondrocytes after activation of A2AR in 2 OA animal models.

The mTOR pathway integrates both extracellular and intracellular signals and serves as a central regulator of cell metabolism, growth, survival, and stress responses. Neurotropic viruses, such as herpes simplex virus-1 (HSV-1), also rely on cellular AKT-mTORC1 signaling to achieve viral latency. Here, we define a novel genotoxic response whereby spatially separated signals initiated by extracellular neurotrophic factors and nuclear DNA damage are integrated by the AKT-mTORC1 pathway. We demonstrate that endogenous DNA double-strand breaks (DSBs) mediated by Topoisomerase 2β-DNA cleavage complex (TOP2βcc) intermediates are required to achieve AKT-mTORC1 signaling and maintain HSV-1 latency in neurons. Suppression of host DNA-repair pathways that remove TOP2βcc trigger HSV-1 reactivation. Moreover, perturbation of AKT phosphorylation dynamics by downregulating the PHLPP1 phosphatase led to AKT mis-localization and disruption of DSB-induced HSV-1 reactivation. Thus, the cellular genome integrity and environmental inputs are consolidated and co-opted by a latent virus to balance lifelong infection with transmission.

BACKGROUND:Little evidence regarding the extent of recovery of radial nerve lesions with associated humerus trauma exists. The aim of this study is to examine the incidence and resolution of types of radial nerve palsy (RNP) in operative and nonoperative humeral shaft fracture populations. MATERIALS AND METHODS/METHODS:Radial nerve lesions were identified as complete (RNPc), which included motor and sensory loss, and incomplete (RNPi), which included sensory-only lesions. Charts were reviewed for treatment type, radial nerve status, RNP resolution time, and follow-up time. Descriptive statistics were used to document incidence of RNP and time to resolution. Independent-samples t-test was used to determine significant differences between RNP resolution time in operative and nonoperative cohorts. RESULTS:A total of 175 patients (77 operative, 98 nonoperative) with diaphyseal humeral shaft injury between 2007 and 2016 were identified and treated. Seventeen out of 77 (22.1%) patients treated operatively were diagnosed preoperatively with a radial nerve lesion. Two (2.6%) patients developed secondary RNPc postoperatively. Eight out of 98 (8.2%) patients presented with RNP postinjury for nonoperatively treated humeral shaft fracture. All patients who presented with either RNPc, RNPi, or iatrogenic RNP had complete resolution of their RNP. No statistically significant difference was found in recovery time when comparing the operative versus nonoperative RNPc, operative versus nonoperative RNPi, or RNPc versus RNPi patient groups. CONCLUSIONS:All 27 (100%) patients presenting with or developing radial nerve palsy in our study recovered. No patient required further surgery for radial nerve palsy. Radial nerve exploration in conjunction with open reduction and internal fixation (ORIF) appears to facilitate speedier resolution of RNP when directly compared with observation in nonoperative cases, although not statistically significantly so. These findings provide surgeons valuable information they can share with patients who sustain radial nerve injury with associated humerus shaft fracture or nonunion. LEVEL OF EVIDENCE/METHODS:Level III treatment study.

Mitochondria contain cardiolipin (CL), an organelle-specific phospholipid that carries four fatty acids with a strong preference for unsaturated chains. Unsaturation is essential for the stability and for the function of mitochondrial CL. Surprisingly, we found tetrapalmitoyl-CL (TPCL), a fully saturated species, in the testes of humans and mice. TPCL was absent from other mouse tissues but was the most abundant CL species in testicular germ cells. Most intriguingly, TPCL was not localized in mitochondria but was in other cellular membranes even though mitochondrial CL was the substrate from which TPCL was synthesized. During spermiogenesis, TPCL became associated with the acrosome, a sperm-specific organelle, along with a subset of authentic mitochondrial proteins, including Ant4, Suox, and Spata18. Our data suggest that mitochondria-derived membranes are assembled into the acrosome, challenging the concept that this organelle is strictly derived from the Golgi apparatus and revealing a novel function of mitochondria.

The drivers and the specification of CD4⁺ T cell differentiation in the tumor microenvironment and their contributions to tumor immunity or tolerance are incompletely understood. Using models of pancreatic ductal adenocarcinoma (PDA), we show that a distinct subset of tumor-infiltrating dendritic cells (DC) promotes PDA growth by directing a unique T_H-program. Specifically, CD11b⁺CD103^- DC predominate in PDA, express high IL-23 and TGF-β, and induce FoxP3^neg tumor-promoting IL-10⁺IL-17⁺IFNγ^+ regulatory CD4⁺ T cells. The balance between this distinctive T_H program and canonical FoxP3^+ T_REGS is unaffected by pattern recognition receptor ligation and is modulated by DC expression of retinoic acid. This T_H-signature is mimicked in human PDA where it is associated with immune-tolerance and diminished patient survival. Our data suggest that CD11b⁺CD103^- DC promote CD4⁺ T cell tolerance in PDA which may underscore its resistance to immunotherapy.

The purpose of this study was to evaluate whether patients with hip fractures receiving antiplatelet and direct oral anticoagulants treated within 48 hours of admission had worse surgical and clinical outcomes than those whose surgery was delayed more than 48 hours. Consecutive patients 55 years and older with an operatively treated hip fracture were analyzed. Patients receiving the following anticoagulants were included: antiplatelet drugs, factor Xa inhibitors, and direct thrombin inhibitors. Outcomes included surgical blood loss, procedure time, transfusion requirement, length of stay, complication rate, and need for intensive care unit or step-down unit level care. Patients who underwent surgery within 48 hours of presentation were compared with patients whose surgery was delayed more than 48 hours. Of 551 consecutive operative hip fracture patients, 78 (14.2%) were receiving the anticoagulant medications included in this study. Of these 78 patients, 58 had surgery within 48 hours and 20 had surgery after 48 hours. When comparing the early and delayed fixation cohorts, there was no difference in transfusion requirement, length of surgery, or blood loss. Type of anticoagulant made no difference in transfusion requirement, blood loss, or length of surgery. There was also no difference in the mean number of complications or in the need for intensive care unit or step-down unit level care. In this study, patients receiving antiplatelet therapy, factor Xa inhibitors, or direct thrombin inhibitors who underwent surgical fixation of their hip fracture within 48 hours of admission were at no higher risk for transfusion, increased surgical blood loss, longer operative time, or inpatient mortality. [Orthopedics. 201x; xx(x):xx-xx.].

BACKGROUND:Bringing antibodies from pre-clinical studies to human trials requires humanization, but this process may alter properties that are crucial for efficacy. Since pathological tau protein is primarily intraneuronal in Alzheimer's disease, the most efficacious antibodies should work both intra- and extracellularly. Thus, changes which impact uptake or antibody binding will affect antibody efficacy. METHODS:Initially, we examined four tau mouse monoclonal antibodies with naturally differing charges. We quantified their neuronal uptake, and efficacy in preventing toxicity and pathological seeding induced by human-derived pathological tau. Later, we generated a human chimeric 4E6 (h4E6), an antibody with well documented efficacy in multiple tauopathy models. We compared the uptake and efficacy of unmodified and chimeric antibodies in neuronal and differentiated neuroblastoma cultures. Further, we analyzed tau binding using ELISA assays. FINDINGS/RESULTS:Neuronal uptake of tau antibodies and their efficacy strongly depends on antibody charge. Additionally, their ability to prevent tau toxicity and seeding of tau pathology does not necessarily go together. Particularly, chimerization of 4E6 increased its charge from 6.5 to 9.6, which blocked its uptake into human and mouse cells. Furthermore, h4E6 had altered binding characteristics despite intact binding sites, compared to the mouse antibody. Importantly, these changes in uptake and binding substantially decreased its efficacy in preventing tau toxicity, although under certain conditions it did prevent pathological seeding of tau. CONCLUSIONS:These results indicate that efficacy of chimeric/humanized tau antibodies should be thoroughly characterized prior to clinical trials, which may require further engineering to maintain or improve their therapeutic potential. FUND: National Institutes of Health (NS077239, AG032611, R24OD18340, R24OD018339 and RR027990, Alzheimer's Association (2016-NIRG-397228) and Blas Frangione Foundation.

Behavioral choices made by the brain during stress depend on glucocorticoid and brain-derived neurotrophic factor (BDNF) signaling pathways acting in synchrony in the mesolimbic (reward) and corticolimbic (emotion) neural networks. Deregulated expression of BDNF and glucocorticoid receptors in brain valuation areas may compromise the integration of signals. Glucocorticoid receptor phosphorylation upon BDNF signaling in neurons represents one mechanism underlying the integration of BDNF and glucocorticoid signals that when off balance may lay the foundation of maladaptations to stress. Here, we propose that BDNF signaling conditions glucocorticoid responses impacting neural plasticity in the mesocorticolimbic system. This provides a novel molecular framework for understanding how brain networks use BDNF and glucocorticoid signaling contingencies to forge receptive neuronal fields in temporal domains defined by behavioral experience, and in mood disorders.

Hox genes are evolutionarily conserved transcription factors that during embryonic development function as master regulators of positional identity. In postnatal life, the function of Hox proteins is less clear: Hox genes are expressed during tissue repair, but in this context their function(s) are largely unknown. Here we show that Hox genes are expressed in periosteal stem/progenitor cells in a distribution similar to that during embryonic development. Using unbiased sequencing, we established that periosteal stem/progenitor cells from distinct anatomic sites within the skeleton significantly differ in their transcriptome, and that Hox expression status best defines these differences. Lastly, we provide evidence that Hox gene expression is one potential mechanism that maintains periosteal stem/progenitor cells in a more primitive, tripotent state, while suppression of Hox genes leads to fate changes with loss of tripotency. Together, our data describe an adult role of Hox genes other than positional identity, and the modulatory role of Hox genes in fate decisions may offer potential druggable targets for the treatment of fractures, non-unions and bone defects.