Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report.

Schwann cells are essential for the maintenance and function of motor neurons, axonal networks, and the neuromuscular junction. In amyotrophic lateral sclerosis, where motor neuron function is progressively lost, Schwann cell function may also be impaired. Recently, important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been reported. This case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles, marking, to our knowledge, the first instance of such treatment. An 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral sclerosis. After initial diagnosis, the patient underwent a combination of generic riluzole, sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis, and taurursodiol. The patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron function. We confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired (senescent) and that exposure of the patient's Schwann cells to allogeneic Schwann cell-derived exosomal vesicles, cultured expanded from a cadaver donor improved their growth capacity in vitro. After a period of observation lasting 10 weeks, during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored, the patient received weekly consecutive infusions of 1.54 × 10 12 (×2), and then consecutive infusions of 7.5 × 10 12 (×6) allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco's phosphate-buffered saline. None of the infusions were associated with adverse events such as infusion reactions (allergic or otherwise) or changes in vital signs. Clinical lab serum neurofilament and cytokine levels measured prior to each infusion varied somewhat without a clear trend. A more sensitive in-house assay suggested possible inflammasome activation during the disease course. A trend for clinical stabilization was observed during the infusion period. Our study provides a novel approach to address impaired Schwann cells and possibly motor neuron function in patients with amyotrophic lateral sclerosis using allogeneic Schwann cell-derived exosomal vesicles. Initial findings suggest that this approach is safe.

BMP4-Induced Suppression of Breast Cancer Metastasis Is Associated with Inhibition of Cholesterol Biosynthesis.

We reported previously that in preclinical models, BMP4 is a potent inhibitor of breast cancer metastasis and that high BMP4 protein levels predict favourable patient outcomes. Here, we analysed a breast cancer xenograft with or without enforced expression of BMP4 to gain insight into the mechanisms by which BMP4 suppresses metastasis. Transcriptomic analysis of cancer cells recovered from primary tumours and phosphoproteomic analyses of cancer cells exposed to recombinant BMP4 revealed that BMP4 inhibits cholesterol biosynthesis, with many genes in this biosynthetic pathway being downregulated by BMP4. The treatment of mice bearing low-BMP4 xenografts with a cholesterol-lowering statin partially mimicked the anti-metastatic activity of BMP4. Analysis of a cohort of primary breast cancers revealed a reduced relapse rate for patients on statin therapy if their tumours exhibited low BMP4 levels. These findings indicate that BMP4 may represent a predictive biomarker for the benefit of additional statin therapy in breast cancer patients.

Rapamycin Prevents Expansion of Costimulation Blockade-resistant CD8+ Alloreactive Memory Cells following Depletional Induction in Renal Transplant Recipients.

Alemtuzumab induction with belatacept/rapamycin-based maintenance immunotherapy (ABR) prevents kidney allograft rejection and specifically limits early costimulation blockade-resistant rejection (CoBRR). To evaluate the mechanisms by which this regimen alters CoBRR, we characterized the phenotype and functional response of preexisting memory cells to allogeneic endothelial cells using intracellular cytokine staining and flow cytometry. IL-7-induced lymphocyte proliferation in the presence or absence of rapamycin was assessed to characterize the phenotype of proliferating cells. Lymphocytes from 40 recipients who underwent transplant using the ABR regimen were studied longitudinally. The rapid immunoresponses of preexisting alloreactive cells to allogeneic endothelial cells were predominantly CD8+TNF-α+/IFN-γ+ cells. These cells were effector memory (TEM) and terminally differentiated effector memory cells lacking CD28 expression, and most were CD57+PD1-. Neither rapamycin nor belatacept directly inhibited these cells. IL-7, a cytokine induced during lymphopenia postdepletion, provoked dramatic CD8+ TEM cell proliferation and a low level of CD8+CD57+PD1- cell expansion in vitro. The IL-7 stimulation induced CD8+ cell mTOR phosphorylation, and rapamycin treatment markedly inhibited IL-7-induced TEM and CD57+PD1- cell expansion. This effect was evident in patients receiving the ABR in that the repopulation of CD8+CD57+PD1- TEM cells was substantially suppressed for at least 36 mo after transplant. These findings help define one mechanism by which a costimulation blockade/rapamycin-based therapy following alemtuzumab induction minimizes CoBRR, namely that in the presence of rapamycin, costimulation-resistant alloreactive cells are disproportionately ineffective at repopulating following post-transplant T cell depletion.

A novel leucine zipper-like transcriptional regulator 1 variant identified in a pair of siblings with familial schwannomatosis.

Background: Schwannomatosis is a rare genetic disorder marked by the emergence or predisposition to developing multiple schwannomas. Patients typically present with chronic pain or a mass in the second or third decade of life. Schwannomatosis is characterized by its associated gene, or if the specific gene is not known, then a descriptor is used. Here, we report a new Leucine zipper-like transcriptional regulator 1 (LZTR1) pathogenic variant identified in a pair of siblings with familial LZTR1-related schwannomatosis. Case Descriptions: A 35-year-old male presented for evaluation of the left lower extremity pain. Magnetic resonance imaging (MRI) demonstrated multiple lesions throughout his body, highly likely for schwannomatosis. He underwent surgical resection of two of these lesions, located in the left femoral nerve and distal shin. Pathology confirmed that the resected lesions were schwannomas. Six months later, his 34-year-old sister was referred and evaluated for a right ankle mass, previously diagnosed as a ganglion cyst. MRI of her right ankle demonstrated a one-centimeter subcutaneous tumor. She underwent surgical resection, and pathology confirmed that the tumor was a schwannoma. Both siblings elected to undergo genetic analysis for pathogenic variants associated with schwannomatosis. Both results were positive for the c.263del pathogenic variant of the LZTR1 gene associated with LZTR1-related schwannomatosis. Additionally, genetic analysis also determined the mother of the siblings also carried the same c.263del pathogenic variant. Conclusion: There are still schwannomatosis cases with novel switch/sucrose non-fermentable-related matrix-associated actin-dependent regulators of chromatin subfamily B member 1 or LZTR1 mutations to be reported. We report the first three cases of the c.263+1del LZTR1 pathogenic variant causing LZTR1-related schwannomatosis initially found in the two siblings. Identifying further LZTR1 pathogenic variants can give more insight into the pathogenicity of each variant.

Discordance Analysis of VLDL-C and ApoB in UK Biobank and Framingham Study: A Prospective Observational Study.

BACKGROUND: Recent observational and Mendelian randomization analyses have reported significant effects of VLDL-C (very-low density lipoprotein cholesterol) on risk that is independent of ApoB (apolipoprotein B). We aim to determine the independent association of VLDL-C and ApoB with the risk of new onset cardiovascular events in the UK Biobank and Framingham Heart Study cohorts. METHODS: We included 294 289 UK Biobank participants with a median age of 56 years, 42% men, and 2865 Framingham Heart Study participants (median age, 53 years; 47% men). The residual resulting from regressing VLDL-C on ApoB expresses the portion of VLDL-C not explained by ApoB, while the residual from regressing ApoB on VLDL-C expresses the portion of ApoB not explained by VLDL-C. Cox proportional hazards models for atherosclerotic cardiovascular disease incidence were created for residual VLDL-C and residual ApoB. Models were analyzed with and without high-density lipoprotein cholesterol (HDL-C). Furthermore, we investigated the independent effects of VLDL-C after accounting for ApoB and HDL-C and of HDL-C after accounting for ApoB and VLDL-C. RESULTS: In the UK Biobank, ApoB was highly correlated with VLDL-C (r=0.70; P<0.001) but weakly negatively correlated with HDL-C (r=-0.11; P<0.001). The ApoB residual and the VLDL-C residual were significantly associated with new-onset atherosclerotic cardiovascular disease (hazard ratio [HR], 1.08 and 1.05, respectively; P<0.001). After adjusting for HDL-C, the ApoB residual remained similar in magnitude (HR, 1.10; P<0.001), whereas the effect size of the VLDL-C residual was reduced (HR, 1.02; P=0.029). The independent effect of HDL-C (after accounting for ApoB and VLDL-C) remained robust (HR, 0.86; P<0.0001), while the independent effect of VLDL-C (after accounting for ApoB and HDL-C) was modest (HR, 1.02; P=0.029). All results were consistent in the Framingham cohort. CONCLUSIONS: When adjusted for HDL-C, the association of VLDL-C with cardiovascular risk was no longer clinically meaningful. Our residual discordance analysis suggests that adjustment for HDL-C cannot be ignored.

The role of emboli detection studies in acute inpatient vertebral artery dissection.

BACKGROUND: Prompt diagnosis and treatment of vertebral artery dissection (VAD) is critical for preventing stroke. The use of emboli detection studies (EDS) using Doppler ultrasonography is an emerging method that has been proposed to predict stroke risk and guide subsequent treatment. Limited data exists on the predictive value of this emerging modality in the posterior circulation. This study aims to assess the predictive value of emboli detection studies (EDS) in forecasting inpatient stroke in VAD patients and identify associated risk factors. Patients were recruited between January 2009 and January 2018. METHODS: We performed a retrospective analysis of 104 consecutive patients with VAD who underwent EDS at our institution. Patients underwent transcranial ultrasonography for detection of microemboli and were followed clinically and radiographically thereafter for evidence of stroke. RESULTS: A total of 104 patients with spontaneous (58 %), traumatic (39 %) or iatrogenic (4 %) VAD were included in our analysis. Stroke occurred more frequently in patients with spontaneous VAD compared to traumatic VAD (p < 0.001). Microemboli were detected in 17 patients (16 %), including 18.3 % of spontaneous VAD, 12.5 % of traumatic VAD, and 25 % of iatrogenic VAD. 61 patients (59 %) suffered a posterior circulation stroke, however there was no significant association between detection of microemboli and stroke events (60 % of patients without microemboli vs. 53 % of patients with ≥ 1 HITS during EDS; p = 0.6). Similarly, no microemboli were detected in any of the patients who went on to develop a delayed stroke. CONCLUSIONS: In our single-institution retrospective analysis of patients with VAD, the detection of microemboli on EDS was not associated with stroke nor was it predictive of delayed stroke. Additionally, patients with spontaneous VAD may be at higher risk for stroke compared to traumatic VAD.

Adenomas from individuals with pathogenic biallelic variants in the MUTYH and NTHL1 genes demonstrate base excision repair tumour mutational signature profiles similar to colorectal cancers, expanding potential diagnostic and variant classification applications.

Background: Colorectal cancers (CRCs) from people with biallelic germline likely pathogenic/pathogenic variants in MUTYH or NTHL1 exhibit specific single base substitution (SBS) mutational signatures, namely combined SBS18 and SBS36 (SBS18+SBS36), and SBS30, respectively. The aim was to determine if adenomas from biallelic cases demonstrated these mutational signatures at diagnostic levels. Methods: Whole-exome sequencing of FFPE tissue and matched blood-derived DNA was performed on 9 adenomas and 15 CRCs from 13 biallelic MUTYH cases, on 7 adenomas and 2 CRCs from 5 biallelic NTHL1 cases and on 27 adenomas and 26 CRCs from 46 non-hereditary (sporadic) participants. All samples were assessed for COSMIC v3.2 SBS mutational signatures. Results: In biallelic MUTYH cases, SBS18+SBS36 signature proportions in adenomas (mean±standard deviation, 65.6%±29.6%) were not significantly different to those observed in CRCs (76.2%±20.5%, p-value=0.37), but were significantly higher compared with non-hereditary adenomas (7.6%±7.0%, p-value=3.4×10-4). Similarly, in biallelic NTHL1 cases, SBS30 signature proportions in adenomas (74.5%±9.4%) were similar to those in CRCs (78.8%±2.4%) but significantly higher compared with non-hereditary adenomas (2.8%±3.6%, p-value=5.1×10-7). Additionally, a compound heterozygote with the c.1187G>A p.(Gly396Asp) pathogenic variant and the c.533G>C p.(Gly178Ala) variant of unknown significance (VUS) in MUTYH demonstrated high levels of SBS18+SBS36 in four adenomas and one CRC, providing evidence for reclassification of the VUS to pathogenic. Conclusions: SBS18+SBS36 and SBS30 were enriched in adenomas at comparable proportions observed in CRCs from biallelic MUTYH and biallelic NTHL1 cases, respectively. Therefore, testing adenomas may improve the identification of biallelic cases and facilitate variant classification, ultimately enabling opportunities for CRC prevention.

Association of bradykinin receptor 2 (BDKRB2) variants with physical performance and muscle mass: Findings from the LACE sarcopenia trial.

INTRODUCTION: Understanding genetic contributors to sarcopenia (age-related loss of muscle strength and mass) is key to finding effective therapies. Variants of the bradykinin receptor 2 (BDKRB2) have been linked to athletic and muscle performance. The rs1799722-9 and rs5810761 T alleles have been shown to be overrepresented in endurance athletes, possibly due to increased transcriptional rates of the receptor. These variants have been rarely studied in older people or people with sarcopenia. METHODS: We performed a post hoc sub-study of the Leucine and ACE (LACE) inhibitor trial, which enrolled 145 participants aged ≥70 years with low grip strength and low gait speed. Participants' blood samples were genotyped for rs179972 using TaqMan and rs5810761 by amplification through Hotstar Taq. Genotypes were compared with outcomes of physical performance and body composition measures. RESULTS: Data from 136 individuals were included in the analysis. For rs1799722 the genotype frequency (TT: 17, CC: 48, CT: 71) remained in Hardy-Weinberg Equilibrium (HWE p = 0.248). There was no difference between the genotypes for six-Minute Walk Distance (6MWD) or Short Physical Performance Battery (SPPB). Men with the TT genotype had a significantly greater 6MWD than other genotypes (TT 400m vs CT 310m vs CC 314m, p = 0.027), and greater leg muscle mass (TT 17.59kg vs CT 15.04kg vs CC 15.65kg, p = 0.007). For rs5810761, the genotype frequency (-9-9: 31, +9+9: 43, -9+9: 60) remained in HWE (p = 0.269). The +9+9 genotype was associated with a significant change in SPPB score at 12 months (-9-9 0 vs -9+9 0 vs +9+9-1, p<0.001), suggesting an improvement. In men, the -9-9 genotype was associated with lower arm fat (-9-9 2.39kg vs -9+9 2.72kg vs +9+9 2.76kg, p = 0.019). CONCLUSION: In men, the rs1799722 TT genotype was associated with longer 6MWD and greater leg muscle mass, while the rs5810761 -9-9 genotype was associated with lower arm fat mass.

Assessing Survival, Distribution, and Optimal Loading Technique of Schwann Cell-Derived Exosomes Into Second-generation Axon Guidance Channels.

INTRODUCTION: Peripheral nerve injury (PNI) occurs in approximately 3% of all trauma patients and can be challenging to treat, particularly when injury is severe such as with a long-segmental gap. Although peripheral nerves can regenerate after injury, functional recovery is often insufficient, leading to deficits in the quality of life of patients with PNI. Although nerve autografts are the gold standard of care, there are several disadvantages to their use, namely a lack of autologous nerve material for repair. This has led to the pursuit of alternative treatment methods such as axon guidance channels (AGCs). Second-generation AGCs have been shown to be able to deliver growth-enhancing substrates for nerve repair directly to the injury site. Although our laboratory has had success with second-generation AGCs filled with Schwann cells (SCs), SCs have their own set of issues clinically. Because of this, we have begun to utilize SC-derived exosomes as an alternative, as they have the appropriate protein markers, associate to axons in high concentrations, and are able to improve nerve regeneration. However, it is unknown how SC-derived exosomes may react within second-generation AGCs; thus, the aim of the present study was to assess the ability of SC-derived exosomes to be loaded into a second-generation AGC and how they would distribute within it. MATERIALS AND METHODS: A total of 4 dry second-generation AGCs were loaded with SC-derived exosomes that were derived from green fluorescent protein (GFP)-labeled SCs. They were subsequently frozen and sliced before imaging. RESULTS: Here, we present findings that SC-derived exosomes can be loaded into second-generation AGCs through our established loading method utilizing negative pressure and are able to survive and equally distribute along the length of the AGC. CONCLUSIONS: Although only 4 second-generation AGCs were utilized, these findings indicate a potential use for SC-derived exosomes within second-generation AGCs to treat severe PNI. Future research should focus on exploring this in greater detail and in different contexts to assess the ability of SC-derived exosomes to survive at the site of injury and treat PNI.

Genome-wide SNP assessment of contemporary European red deer genetic structure highlights the distinction of peripheral populations and the main admixture zones in Europe.

Genome-wide technologies open up new possibilities to clarify questions on genetic structure and phylogeographic history of taxa previously studied with microsatellite loci and mitochondrial sequences. Here, we used 736 individual red deer (Cervus elaphus) samples genotyped at 35,701 single nucleotide polymorphism loci (SNPs) to assess the population structure of the species throughout Europe. The results identified 28 populations, with higher degrees of genetic distinction in peripheral compared to mainland populations. Iberian red deer show high genetic differentiation, with lineages in Western and Central Iberia maintaining their distinctiveness, which supports separate refugial ranges within Iberia along with little recent connection between Iberian and the remaining Western European populations. The Norwegian population exhibited the lowest variability and the largest allele frequency differences from mainland European populations, compatible with a history of bottlenecks and drift during post-glacial colonization from southern refugia. Scottish populations showed high genetic distance from the mainland but high levels of diversity. Hybrid zones were found between Eastern and Western European lineages in Central Europe as well as in the Pyrenees, where red deer from France are in close contact with Iberian red deer. Anthropogenic restocking has promoted the Pyrenean contact zone, admixture events in populations on the Isle of Rum and in the Netherlands, and at least partly the admixture of the two main lineages in central-eastern Europe. Our analysis enabled detailed resolution of population structure of a large mammal widely distributed throughout Europe and contributes to resolving the evolutionary history, which can also inform conservation and management policies.

Acute Surgical Site Complications in Direct Anterior Total Hip Arthroplasty: Impact of Local Subcutaneous Tissue Depth and Body Mass Index.

Background: Body mass index (BMI) is an imperfect measure of patients' adiposity and operative risk. Radiographic and direct subcutaneous measurements have been utilized in attempts to more accurately characterize the risk of postoperative complications, including surgical site infection. This study aims to evaluate whether direct tissue depth measurement is a more accurate predictor of skin complication following direct anterior total hip arthroplasty (THA). Methods: A retrospective chart review of patients who underwent elective THA between April 30, 2020, and January 31, 2023, was performed. Baseline demographics, antibiotics, anticoagulation, and intraoperatively measured tissue depths at proximal, middle, and distal portions of the incision were recorded. Patient follow-up was reviewed to assess the development of skin complication in the acute postoperative period. Results: Data were collected from 280 patients who underwent THA via direct anterior approach by a single surgeon. The mean age was 66.0 years, and 52.1% were female. A total of 18/280 (6.4%) patients developed an abrasion (5/18) or superficial surgical site infection (13/18) within the first 60 days postoperatively. Patients who developed skin complications had a significantly higher BMI (33.7 kg/m2 vs 29.9 kg/m2; P = .0021). Patients with a BMI >30 kg/m2 had more than 5 times increased odds of developing a superficial skin complication in the acute 60-day postoperative period compared to those with a BMI <30 kg/m2 (Odds ratio = 5.318, P = .0059). None of the measured tissue depths, nor their average together, were shown to be significant predictors of skin complications. Conclusions: This study showed that BMI is a significant predictor of acute skin complications in direct anterior THA patients. No other significant predictors were found to be associated with increased risk, including proximal, middle, and distal tissue depths.

Functional diversity of bacterial microbiota associated with the toxigenic benthic dinoflagellate Prorocentrum.

Interactions between bacterial microbiota and epibenthic species of the dinoflagellate Prorocentrum may define the onset and persistence of benthic harmful algal blooms (bHABs). Chemical ecological interactions within the dinoflagellate phycosphere potentially involve a complex variety of organic molecules, metabolites, and toxins, including undefined bioactive compounds. In this study, the bacterial diversity and core members of the dinoflagellate-associated microbiota were defined from 11 strains of three epibenthic Prorocentrum species, representing three geographically disjunct locations within Mexican coastal waters. Microbiota profiles in stable monoclonal Prorocentrum cultures were obtained by sequencing amplicons of the V3-V4 region of the 16S rRNA gene. Thirteen classes of bacteria were identified among dinoflagellate clones, where Alphaproteobacteria, Gammaproteobacteria, and Bacteroidia were consistently dominant. The bacterial community structure exhibited significantly different grouping by the location of origin of dinoflagellate clones. No significant diversity difference was found among free-living or unattached bacteria in the dinoflagellate culture medium (M) compared with those in closer association with the dinoflagellate host cells (H). Twelve taxa were defined as core members of the bacterial assemblage, representing the genera Algiphilus, Cohaesibacter, Labrenzia, Mameliella, Marinobacter, Marivita, Massilia, Muricauda, Roseitalea, and an unclassified member of the Rhodobacteraceae. The core members are inferred to significantly contribute to primary and secondary metabolic functions, but no direct correlation with dinoflagellate toxigenicity was apparent. Overall the bacterial profile and implied gene functionality indicated a suite of positive interactions, suggesting either mutualism or commensalism with the dinoflagellate. The further characterization and interpretation of specific gene functions and interactions between bacteria and dinoflagellates, such as epibenthic members of genus Prorocentrum, are key to understanding their role in toxigenesis and bHAB development.

Associations Between Neighborhood Racialized Economic Segregation with Cardiometabolic Health and Cortisol in a Racially/Ethnically Diverse Sample of Children from Minneapolis-St. Paul.

Introduction: Past research shows that structural racism contributes to disparities in cardiometabolic health among racially/ethnically minoritized populations. Methods: This cross-sectional study examined the correlation between census tract-level racialized economic segregation and child health metrics among a racially and ethnically diverse cohort of 350 children (ages 6.5-13.8) from Minneapolis-St. Paul, MN. Results: A consistent cardiometabolic and cortisol outcome gradient was observed across the index of concentration at the extremes tertiles, such that health risk factors increased as tract privilege decreased. Conclusion: Racialized economic segregation was associated with less favorable child health outcomes, underscoring the potential importance of place-based interventions for promoting children's health.

The Causal-Benefit Model to Prevent Cardiovascular Events.

Selecting individuals for preventive lipid-lowering therapy is presently governed by the 10-year risk model. Once a prespecified level of cardiovascular disease risk is equaled or exceeded, individuals become eligible for preventive lipid-lowering therapy. A key limitation of this model is that only a small minority of individuals below the age of 65 years are eligible for therapy. However, just under one-half of all cardiovascular disease events occur below this age. Additionally, in many, the disease that caused their events after 65 years of age developed and progressed before 65 years of age. The causal-benefit model of prevention identifies individuals based both on their risk and the estimated benefit from lowering atherogenic apoB lipoprotein levels. Adopting the causal-benefit model would increase the number of younger subjects eligible for preventive treatment, would increase the total number of cardiovascular disease events prevented at virtually the same number to treat, and would be cost-effective.