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Xuan-Wei Huang,1,* Xu-Dong Wang,2,* Jie-Lan Lai,2 Ya-Li Lu,2 Kun Deng,3 Ren-Chun Lai2 1The First Affiliated Hospital of Sun Yat-Sen University, Department of Anesthesiology, Guangzhou 510080, People’s Republic of China; 2State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Department of Anesthesiology, Guangzhou 510060, People’s Republic of China; 3Xifeng People’s Hospital, Department of Anesthesiology, Guiyang 520122, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ren-Chun Lai Email lairch@sysucc.org.cnBackground: Whether laryngeal cancer is directly implanted into the lungs during orotracheal intubation is still unclear. Therefore, this study aimed to find whether orotracheal intubation is an independent risk factor for postoperative pulmonary metastasis in patients undergoing laryngectomy.Patients and Methods: Medical records from January 1, 2006, to December 31, 2016, were reviewed. According to similar propensity scores, patients who received orotracheal intubation (tracheal intubation group, n = 515) were matched 1:1 with those who received tracheotomy (tracheotomy group, n = 326) in the induction of general anesthesia. The primary outcome was postoperative pulmonary metastasis. Secondary outcomes included local recurrence, lymphatic metastasis, tracheostomal recurrence and overall survival.Results: Between the two groups, there was no significant difference in postoperative pulmonary metastasis (P = 0.688), local recurrence (P = 0.215), lymphatic metastasis (P = 0.480), tracheostomal recurrence (P = 0.246) or all-cause death (P = 0.299). The primary site of cancer was an independent risk factor for pulmonary metastasis [HR 0.29, 95% CI 0.13– 0.68; P = 0.013] and local recurrence (HR 2.69, 95% CI 1.39– 5.21; P = 0.003). Type of surgery (HR 3.13, 95% CI 2.03– 4.84; P < 0.001) and N classification of TNM (HR 0.27, 95% CI 0.10– 0.75; P = 0.012) were risk factors for local recurrence. Postoperative chemotherapy was an independent risk factor for lung metastasis (HR 7.58, 95% CI 3.11– 18.47; P < 0.001) and lymphatic metastasis (HR 5.18, 95% CI 2.57– 11.91; P < 0.001), and 5-year overall survival was associated with age (P = 0.028), clinical stage (P < 0.001) and postoperative chemotherapy (P = 0.003) but not with anesthetic technique (P = 0.473).Conclusion: This retrospective study suggests that orotracheal intubation in laryngectomy is not a risk factor for postoperative pulmonary metastasis, local recurrence, lymphatic metastasis or overall survival.Keywords: laryngectomy, lung metastasis, local recurrence, tracheal intubation, tracheotomy

Objective: To investigate the possible pathogenesis and possible risk factors of tinnitus related to female menopause. Methods: From April 2016 to October 2016, 59 female patients with menopausal syndrome were diagnosed in the menopause comprehensive management clinic. Tinnitus and menopause questionnaires were conducted, based on whether having tinnitus, those patients were divided into two groups: tinnitus group and no tinnitus group. Age, body mass index (BMI), Kupperman menopausal index (KMI) score, follicle-stimulating hormone (FSH) level of patients in the two groups were analyzed. Menopausal symptoms, related medical history and possible related factors of tinnitus were statistically analyzed. Results: A total of 59 cases were collected, 22 of which were accompanied by tinnitus. The incidence of idiopathic tinnitus was 35.1% (20/57) because 2 cases of thyroid related tinnitus with clear etiology were removed. Complete data were obtained from 17 of 20 patients with idiopathic tinnitus and 26 of 37 patients without tinnitus. Age, BMI, menopause KMI score, hormone level, menopause symptoms and possible factors related to tinnitus were statistically analyzed between the two groups, and the incidence of headache was statistically different between the two groups ( χ 2 =9.098, P =0.003), but no other factors were statistically significant( P >0.05). The severity of insomnia and tinnitus were further analyzed ( χ 2 =2.841, P =0.417), and there was no significant difference between the two groups. Conclusion: Headache history may be one of the high risk factors for the occurrence of menopausal tinnitus.

Mesenchymal stem/stromal cells (MSC) have displayed promising therapeutic potential. Nonetheless, no United States Food and Drug Administration (FDA)-approved MSC product exists due largely to the absence of a reliable potency assay based on the mechanisms of action to ensure consistent efficacy. MSCs are now thought to exert their effects primarily by releasing small extracellular vesicles (sEVs) of 50-200 nm. While non-living MSC-sEV drugs offer distinct advantages over larger, living MSC drugs, elucidating their mechanism of action to develop robust potency assays remains a challenge. A pivotal prelude to elucidating the mechanism of action for MSC-sEVs is how extracellular vesicles (EVs) engage their primary target cells. Given the inherent inefficiencies of processes such as endocytosis, endosomal escape and EV uncoating during cellular internalization, we propose an alternative EV-cell engagement: EMCEV (Extracellular Modulation of Cells by EV). This approach involves extracellular modulation by EV attributes to generate signaling/inhibitory molecules that have the potential to affect many cells within the vicinity, thereby eliciting a more widespread tissue response., Competing Interests: Conflict of Interest Statement The authors declare no conflicts of interest., (Copyright © 2024 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Mesenchymal stem/stromal cell-derived small extracellular vesicles (MSC-sEVs) are promising therapeutic agents. In this study, we investigated how the administration route of MSC-sEVs affects their therapeutic efficacy in a mouse model of bleomycin (BLM)-induced skin scleroderma (SSc). We evaluated the impact of topical (TOP), subcutaneous (SC), and intraperitoneal (IP) administration of MSC-sEVs on dermal fibrosis, collagen density, and thickness. All three routes of administration significantly reduced BLM-induced fibrosis in the skin, as determined by Masson's Trichrome staining. However, only TOP administration reduced BLM-induced dermal collagen density, with no effect on dermal thickness observed for all administration routes. Moreover, SC, but not TOP or IP administration, increased anti-inflammatory profibrotic CD163 + M2 macrophages. These findings indicate that the administration route influences the therapeutic efficacy of MSC-sEVs in alleviating dermal fibrosis, with TOP administration being the most effective, and this efficacy is not mediated by M2 macrophages. Since both TOP and SC administration target the skin, the difference in their efficacy likely stems from variations in MSC-sEV delivery in the skin. Fluorescence-labelled TOP, but not SC MSC-sEVs when applied to skin explant cultures, localized in the stratum corneum. Hence, the superior efficacy of TOP over SC MSC-sEVs could be attributed to this localization. A comparison of the proteomes of stratum corneum and MSC-sEVs revealed the presence of >100 common proteins. Most of these proteins, such as filaggrin, were known to be crucial for maintaining skin barrier function against irritants and toxins, thereby mitigating inflammation-induced fibrosis. Therefore, the superior efficacy of TOP MSC-sEVs over SC and IP MSC-sEVs against SSc is mediated by the delivery of proteins to the stratum corneum to reinforce the skin barrier.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, accounting for 31% of all deaths globally. Myocardial ischemia-reperfusion injury (IRI), a common complication of CVDs, is a major cause of mortality and morbidity. Studies have shown efficacious use of mesenchymal stem cells-derived small extracellular vesicles (MSCs-EVs) to mitigate IRI in animals, but few research has been done on human-related models. In this study, human embryonic stem cell-derived chambered cardiac organoid (CCO) was used as a model system to study the effects of MSC-EVs on myocardial IRI. The results revealed that MSC-EVs treatment reduced apoptosis and improved contraction resumption of the CCOs. Metabolomics analysis showed that this effect could be attributed to EVs' ability to prevent the accumulation of unsaturated very long-chain fatty acids (VLCFAs). This was corroborated when inhibition of fatty acid synthase, which was reported to reduce VLCFAs, produced a similar protective effect to EVs. Overall, this study uncovered the mechanistic role of MSC-EVs in mitigating IRI that involves preventing the accumulation of unsaturated VLCFA, decreasing cell death, and improving contraction resumption in CCOs., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Mesenchymal stem/stromal cells (MSCs) are an extensively studied cell type in clinical trials due to their easy availability, substantial ex vivo proliferative capacity, and therapeutic efficacy in numerous pre-clinical animal models of disease. The prevailing understanding suggests that their therapeutic impact is mediated by the secretion of exosomes. Notably, MSC exosomes present several advantages over MSCs as therapeutic agents, due to their non-living nature and smaller size. However, despite their promising therapeutic potential, the clinical translation of MSC exosomes is hindered by an incomplete understanding of their biodistribution after administration. A primary obstacle to this lies in the lack of robust labels that are highly sensitive, capable of directly and easily tagging exosomes with minimal non-specific labeling artifacts, and sensitive traceability with minimal background noise. One potential candidate to address this issue is radioactive iodine. Protocols for iodinating exosomes and tracking radioactive iodine in live imaging are well-established, and their application in determining the biodistribution of exosomes has been reported. Nevertheless, the effects of iodination on the structural or functional activities of exosomes have never been thoroughly examined. In this study, we investigate these effects and report that these iodination methods abrogate CD73 enzymatic activity on MSC exosomes. Consequently, the biodistribution of iodinated exosomes may reflect the biodistribution of denatured exosomes rather than functionally intact ones.

Background: Tactile and mechanical pain are crucial to our interaction with the environment, yet the underpinning molecular mechanism is still elusive. Endophilin A2 (EndoA2) is an evolutionarily conserved protein that is documented in the endocytosis pathway. However, the role of EndoA2 in the regulation of mechanical sensitivity and its underlying mechanisms are currently unclear., Methods: Male and female C57BL/6 mice (8-12 weeks) and male cynomolgus monkeys (7-10 years old) were used in our experiments. Nerve injury-, inflammatory-, and chemotherapy-induced pathological pain models were established for this study. Behavioral tests of touch, mechanical pain, heat pain, and cold pain were performed in mice and nonhuman primates. Western blotting, immunostaining, co-immunoprecipitation, proximity ligation and patch-clamp recordings were performed to gain insight into the mechanisms., Results: The results showed that EndoA2 was primarily distributed in neurofilament-200-positive (NF200 + ) medium-to-large diameter dorsal root ganglion (DRG) neurons of mice and humans. Loss of EndoA2 in mouse NF200 + DRG neurons selectively impaired the tactile and mechanical allodynia. Furthermore, EndoA2 interacted with the mechanically sensitive ion channel Piezo2 and promoted the membrane trafficking of Piezo2 in DRG neurons. Moreover, as an adaptor protein, EndoA2 also bound to kinesin family member 5B (KIF5B), which was involved in the EndoA2-mediated membrane trafficking process of Piezo2. Loss of EndoA2 in mouse DRG neurons damaged Piezo2-mediated rapidly adapting mechanically activated currents, and re-expression of EndoA2 rescued the MA currents. In addition, interference with EndoA2 also suppressed touch sensitivity and mechanical hypersensitivity in nonhuman primates., Conclusions: Our data reveal that the KIF5B/EndoA2/Piezo2 complex is essential for Piezo2 trafficking and for sustaining transmission of touch and mechanical hypersensitivity signals. EndoA2 regulates touch and mechanical allodynia via kinesin-mediated Piezo2 trafficking in sensory neurons. Our findings identify a potential new target for the treatment of mechanical pain., (© 2024. The Author(s).)

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation and damage, often associated with an imbalance in M1/M2 macrophages. Elevated levels of anti-inflammatory M2 macrophages have been linked to a therapeutic response in RA. We have previously demonstrated that mesenchymal stem/stromal cell small extracellular vesicles (MSC-sEVs) promote M2 polarization and hypothesized that MSC-sEVs could alleviate RA severity with a concomitant increase in M2 polarization. Here, we treated a mouse model of collagen-induced arthritis (CIA) with MSC-sEVs. Relative to vehicle-treated CIA mice, both low (1 μg) and high (10 μg) doses of MSC-sEVs were similarly efficacious but not as efficacious as Prednisolone, the positive control. MSC-sEV treatment resulted in statistically significant reductions in disease progression rate and disease severity as measured by arthritic index (AI), anti-CII antibodies, IL-6, and C5b-9 plasma levels. There were no statistically significant differences in the treatment outcome between low (1 μg) and high (10 μg) doses of MSC-sEVs. Furthermore, immunohistochemical analysis revealed that concomitant with the therapeutic efficacy, MSC-sEV treatment increased anti-inflammatory M2 macrophages and decreased pro-inflammatory M1 macrophages in the synovium. Consistent with increased M2 macrophages, histopathological examination also revealed reduced inflammation, pannus formation, cartilage damage, bone resorption, and periosteal new bone formation in the MSC-sEV-treated group compared to the vehicle group. These findings suggest that MSC-sEVs are potential biologic disease-modifying antirheumatic drugs (DMARDs) that can help slow or halt RA joint damage and preserve joint function.

The most clinically trialed cells, mesenchymal stromal cells (MSCs), are now known to mainly exert their therapeutic activity through paracrine secretions, which include exosomes. To mitigate potential regulatory concerns on the scalability and reproducibility in the preparations of MSC exosomes, MSC exosomes were produced using a highly characterized MYC-immortalized monoclonal cell line. These cells do not form tumors in athymic nude mice or exhibit anchorage-independent growth, and their exosomes do not carry MYC protein or promote tumor growth. Unlike intra-peritoneal injections, topical applications of MSC exosomes in a mouse model of IMQ-induced psoriasis alleviate interleukin (IL)-17, IL-23 and terminal complement complex, C5b9 in psoriatic skin. When applied on human skin explants, fluorescence from covalently labeled fluorescent MSC exosomes permeated and persisted in the stratum corneum for about 24 hours with negligible exit out of the stratum corneum into the underlying epidermis. As psoriatic stratum corneums are uniquely characterized by activated complements and Munro microabscesses, we postulated that topically applied exosomes permeate the psoriatic stratum corneum to inhibit C5b9 complement complex through CD59, and this inhibition attenuated neutrophil secretion of IL-17. Consistent with this, we demonstrated that assembly of C5b9 on purified human neutrophils induced IL-17 secretion and this induction was abrogated by MSC exosomes, which was in turn abrogated by a neutralizing anti-CD 59 antibody. We thus established the mechanism of action for the alleviation of psoriatic IL-17 by topically applied exosomes., Competing Interests: Declaration of Competing Interest SKL holds founding shares in Paracrine Therapeutics., (Copyright © 2023 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Mesenchymal stromal/stem cell (MSC) therapies are currently being explored for dental pulp regeneration. As the therapeutic effects of MSCs in tissue repair are mediated mainly through the release of extracellular vesicles (EVs) including exosomes, we investigated here the cellular processes and molecular mechanisms modulated by MSC exosomes in dental pulp regeneration. Using dental pulp cell (DPC) cultures, we demonstrated that MSC exosomes could increase DPC migration, proliferation, and odontogenic differentiation. The enhancement of these cellular processes was mediated through exosomal CD73-mediated adenosine receptor activation of AKT and ERK signaling. Consistent with these observations, MSC exosomes increased the expression of dentin matrix proteins and promoted the formation of dentin-like tissue and bridge-like structures in a rat pulp defect model. These effects were comparable to that of mineral trioxide aggregate (MTA) treatment. MSC exosomes also yielded recellularized pulp-dentin tissues in the root canal of endodontically-treated human premolars, following subcutaneous implantation in the mouse dorsum. Together, our findings suggest that MSC exosomes could exert a multi-faceted effect on DPC functions including migration, proliferation and odontogenic differentiation to promote dental pulp regeneration. This study provides the basis for development of MSC exosomes as a cell-free MSC therapeutic alternative for pulp-dentin regeneration., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Sai Kiang Lim reports a relationship with Paracrine Therapeutics Pte Ltd that includes: equity or stocks., (© 2023 The Authors. Published by Elsevier Ltd.)

Mesenchymal stem/stromal cell (MSC) exosomes have been shown to alleviate immune dysfunction and inflammation in preclinical animal models. This therapeutic effect is attributed, in part, to their ability to promote the polarization of anti-inflammatory M2-like macrophages. One polarization mechanism has been shown to involve the activation of the MyD88-mediated toll-like receptor (TLR) signaling pathway by the presence of extra domain A-fibronectin (EDA-FN) within the MSC exosomes. Here, we uncovered an additional mechanism where MSC exosomes mediate M2-like macrophage polarization through exosomal CD73 activity. Specifically, we observed that polarization of M2-like macrophages by MSC exosomes was abolished in the presence of inhibitors of CD73 activity, adenosine receptors A 2A and A 2B , and AKT/ERK phosphorylation. These findings suggest that MSC exosomes promote M2-like macrophage polarization by catalyzing the production of adenosine, which then binds to adenosine receptors A 2A and A 2B to activate AKT/ERK-dependent signaling pathways. Thus, CD73 represents an additional critical attribute of MSC exosomes in mediating M2-like macrophage polarization. These findings have implications for predicting the immunomodulatory potency of MSC exosome preparations.

Mesenchymal stem/stromal cell small extracellular vesicles (MSC-sEVs) have shown promise in treating a wide range of animal models of various human diseases, which has led to their consideration for clinical translation. However, the possibility of contraindication for MSC-sEV use is an important consideration. One concern is that MSC-sEVs have been shown to induce M2 macrophage polarization, which is known to be pro-fibrotic, potentially indicating contraindication in fibrotic diseases such as liver fibrosis. Despite this concern, previous studies have shown that MSC-sEVs alleviate high-fat diet (HFD)-induced non-alcoholic steatohepatitis (NASH). To assess whether the pro-fibrotic M2 macrophage polarization induced by MSC-sEVs could worsen liver fibrosis, we first verified that our MSC-sEV preparations could promote M2 polarization in vitro prior to their administration in a mouse model of NASH. Our results showed that treatment with MSC-sEVs reduced or had comparable NAFLD Activity Scores and liver fibrosis compared to vehicle- and Telmisartan-treated animals, respectively. Although CD163 + M2 macrophages were increased in the liver, and serum IL-6 levels were reduced in MSC-sEV treated animals, our data suggests that MSC-sEV treatment was efficacious in reducing liver fibrosis in a mouse model of NASH despite an increase in pro-fibrotic M2 macrophage polarization.

Corneal scarring is a leading cause of worldwide blindness. Human mesenchymal stem cells (MSC) have been reported to promote corneal wound healing through secreted exosomes. This study investigated the wound healing and immunomodulatory effects of MSC-derived exosomes (MSC-exo) in corneal injury through an established rat model of corneal scarring. After induction of corneal scarring by irregular phototherapeutic keratectomy (irrPTK), MSC exosome preparations (MSC-exo) or PBS vehicle as controls were applied to the injured rat corneas for five days. The animals were assessed for corneal clarity using a validated slit-lamp haze grading score. Stromal haze intensity was quantified using in-vivo confocal microscopy imaging. Corneal vascularization, fibrosis, variations in macrophage phenotypes, and inflammatory cytokines were evaluated using immunohistochemistry techniques and enzyme-linked immunosorbent assays (ELISA) of the excised corneas. Compared to the PBS control group, MSC-exo treatment group had faster epithelial wound closure (0.041), lower corneal haze score ( p = 0.002), and reduced haze intensity ( p = 0.004) throughout the follow-up period. Attenuation of corneal vascularisation based on CD31 and LYVE-1 staining and reduced fibrosis as measured by fibronectin and collagen 3A1 staining was also observed in the MSC-exo group. MSC-exo treated corneas also displayed a regenerative immune phenotype characterized by a higher infiltration of CD163+, CD206+ M2 macrophages over CD80+, CD86+ M1 macrophages ( p = 0.023), reduced levels of pro-inflammatory IL-1β, IL-8, and TNF-α, and increased levels of anti-inflammatory IL-10. In conclusion, topical MSC-exo could alleviate corneal insults by promoting wound closure and reducing scar development, possibly through anti-angiogenesis and immunomodulation towards a regenerative and anti-inflammatory phenotype.

This study aims to investigate the mechanisms of human mesenchymal stem cell-derived extracellular vesicles (HuMSC-EV)-induced proangiogenic paracrine effects after radiation injury. HuMSC-EV were locally administered in mice hindlimb following 80-Gy X-ray irradiation and animals were monitored at different time points. HuMSC-EV improved neovascularization of the irradiated tissue, by stimulating angiogenesis, normalizing cutaneous blood perfusion, and increasing capillary density and production of proangiogenic factors. HuMSC-EV also stimulated vasculogenesis by promoting the recruitment and differentiation of bone marrow progenitors. Moreover, HuMSC-EV improved arteriogenesis by increasing the mobilization of monocytes from the spleen and the bone marrow and their recruitment into the muscle, with a pro-inflammatory potential. Importantly, monocyte depletion by clodronate treatment abolished the proangiogenic effect of HuMSC-EV. The critical role of Ly6C(hi) monocyte subset in HuMSC-EV-induced neovascularization process was further confirmed using Ccr2 -/- mice. This study demonstrates that HuMSC-derived EV enhances the neovascularization process in the irradiated tissue by increasing the production of proangiogenic factors, promoting the recruitment of vascular progenitor cells, and the mobilization of innate cells to the injured site. These results support the concept that HuMSC-EV might represent a suitable alternative to stem cells for therapeutic neovascularization in tissue repair., (© 2023. The Author(s).)

Complements and neutrophils are two key players of the innate immune system that are widely implicated as drivers of severe COVID-19 pathogenesis, as evident by the direct correlation of respiratory failure and mortality with elevated levels of terminal complement complex C5b-9 and neutrophils. In this study, we identified a feed-forward loop between complements and neutrophils that could amplify and perpetuate the cytokine storm seen in severe SARS-CoV-2-infected patients. We observed for the first time that the terminal complement activation complex C5b-9 directly triggered neutrophil extracellular trap (NET) release and interleukin (IL)-17 production by neutrophils. This is also the first report that the production of NETs and IL-17 induced by C5b-9 assembly on neutrophils could be abrogated by mesenchymal stem cell (MSC) exosomes. Neutralizing anti-CD59 antibodies abolished this abrogation. Based on our findings, we hypothesize that MSC exosomes could alleviate the immune dysregulation in acute respiratory failure, such as that observed in severe COVID-19 patients, by inhibiting complement activation through exosomal CD59, thereby disrupting the feed-forward loop between complements and neutrophils to inhibit the amplification and perpetuation of inflammation during SARS-CoV-2 infection., Competing Interests: Declaration of Competing Interests SKL holds founding shares in Paracrine Therapeutics., (Copyright © 2022 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Background: The objective of this study was to examine the therapeutic effects of human mesenchymal stromal/stem cell (MSC) exosomes in a rat model of growth plate injury., Methods: A growth plate defect was surgically created on the distal part of the right femur of 40 female Sprague-Dawley rats. A single intra-articular injection of 100 µg of MSC exosomes in 100 µL of phosphate-buffered saline solution (PBS), or an equivalent volume of PBS alone, was administered to the right knee immediately after surgery. At 4 and 8 weeks post-treatment, limb length was measured with micro-CT, and tissue repair was assessed with histological, immunohistochemical, and histomorphometric analyses., Results: A single injection of MSC exosomes significantly increased limb length from 3.29 ± 0.07 cm at 4 weeks to 3.37 ± 0.11 cm at 8 weeks (p = 0.047). However, no improvement in limb length was observed in the PBS control group. The limb-length discrepancy between the involved limb and the contralateral limb in the exosome-treated group was significantly less than the discrepancy in the PBS-treated group at both 4 weeks (2.52% ± 1.30% versus 4.11% ± 0.93%; p = 0.006) and 8 weeks (5.27% ± 2.11% versus 8.06% ± 2.56%; p = 0.016). Consistent with the reduced limb-length discrepancy, the exosome-treated defects displayed significantly more chondrocytes (p < 0.05) and a higher area percentage with deposition of sulphated glycosaminoglycan (p < 0.05) and collagen II (p < 0.05) than PBS-treated defects at 8 weeks. However, bone bridge formation was not inhibited in either group., Conclusions: A single intra-articular injection of MSC exosomes significantly enhanced physeal repair and reduced limb-length discrepancy but did not inhibit bone-bridge formation., Clinical Relevance: This proof-of-concept study demonstrates for the first time the potential use of MSC exosomes as a minimally invasive cell-free therapeutic to promote physeal repair and reduce limb-length discrepancy following growth plate injuries., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G937)., (Copyright © 2022 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Whether more tumor numbers detected in surgery compared to preoperative image affecting survival of colorectal liver metastases (CRLM) patients after hepatectomy combined with microwave ablation (MWA) remains unclear., Methods: From 2013 to 2018, 85 CRLM patients who underwent hepatectomy combined with MWA were retrospectively assessed. Compared to the tumor numbers in preoperative image, patients with equal intraoperative tumor numbers were defined as the equal number group ( n = 45); patients detected more tumor numbers in surgery were defined as the more number group ( n = 40). Clinicopathological factors and prognosis were compared between two groups., Results: Compared to the equal number group, the more number group was characterized by more lymphatic metastasis, synchronous metastasis of liver lesion, and tumor numbers over 5 (all P < 0.05). Median survival time was 46.7 months and 26.8 months in the equal and more number group. Significantly worse overall survival (OS) was found in more number group to the equal number group ( P = 0.027). In Cox analysis, more tumor number than image and high level of carbohydrate antigen 19-9 (CA19-9) were poor prognostic factors for OS., Conclusion: In patients receiving hepatectomy combined with MWA, detecting more liver metastases in surgery than preoperative image indicates poor long-term survival. These patients were characterized by more lymphatic metastasis, synchronous metastasis of liver lesion, and tumor numbers over 5. Intensive follow-up to detect early recurrence and potent postoperative therapy to improve survival may be justified in patients detected more tumor numbers in surgery with a high CA19-9 level., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Ling-Min Jiang et al.)

Objectives: To examine US commercial health plans' adoption of 2018 FDA-approved drugs., Study Design: Database analysis., Methods: We identified novel drugs that the FDA approved in 2018 and categorized them as follows: cancer treatment, orphan drug, included in an expedited review program, and biosimilar. Using a data set of 17 large health plans' drug coverage policies and formularies, we examined coverage 1 year following FDA approval., Results: The FDA approved 66 drugs in 2018 (5 were not yet marketed 1 year following approval). For 60 of 61 drugs, some plans issued coverage policies whereas other plans included the drug in their formularies. Plans imposed restrictions (eg, step therapy) in 37% (275/742) of coverage policies. Plans covered biosimilars, orphan drugs, and cancer treatments more generously than drugs not in those categories (P < .05). Plans imposed restrictions in their policies with different frequencies (range, 7%-52%). Plans imposed utilization management (UM) in 82% (3837/4697) of formulary entries. Of those entries, plans required prior authorizations in 98%, included drugs on the highest patient co-payment tier in 70%, and imposed step therapy in 3%. Plans most often placed orphan drugs and cancer treatments on the highest cost-sharing formulary tiers (68% and 64% of the time, respectively). Plans imposed UM in their formularies with different frequencies (range, 62%-100% of entries)., Conclusions: Health plans imposed fewer coverage restrictions on cancer treatments, orphan drugs, and biosimilars than on drugs not in those categories. Some plans covered 2018 FDA-approved drugs more generously than others, which has implications for patients' access to innovative therapies.

Background: Previous studies have reported the efficacy of human mesenchymal stem cell (MSC) exosomes for the repair of osteochondral defects in rats and rabbits. However, the safety and efficacy of MSC exosomes remain to be validated in a clinically relevant large animal model., Purpose: To validate the safety and efficacy of human MSC exosomes for osteochondral repair in a clinically relevant micropig model., Study Design: Controlled laboratory study., Methods: Bilateral osteochondral defects (6-mm diameter and 1-mm depth) were surgically created in the medial femoral condyles in knees of 12 micropigs. The pigs then received 2-mL intra-articular injections of MSC exosomes and hyaluronic acid (HA) (Exosome+HA) or HA alone after surgery and thereafter at 8 and 15 days. Osteochondral repair was assessed by magnetic resonance imaging (MRI) at 15 days and at 2 and 4 months after surgery as well as by macroscopic, histological, biomechanical, and micro-computed tomography (micro-CT) analyses at 4 months after surgery., Results: Exosome+HA-treated defects demonstrated significantly better MRI scores than HA-treated defects at 15 days and at 2 and 4 months. Additionally, Exosome+HA-treated defects demonstrated functional cartilage and subchondral bone repair, with significantly better macroscopic and histological scores and biomechanical properties (Young modulus and stiffness) than HA-treated defects at 4 months. Micro-CT further showed significantly higher bone volume and trabecular thickness in the subchondral bone of Exosome+HA-treated defects than that of HA-treated defects. Importantly, no adverse response or major systemic alteration was observed in any of the animals., Conclusion: This study shows that the combination of MSC exosomes and HA administered at a clinically acceptable frequency of 3 weekly intra-articular injections can promote functional cartilage and subchondral bone repair, with significantly improved morphological, histological, and biomechanical outcomes in a clinically relevant porcine model., Clinical Relevance: Our findings provide a robust scientific rationale to support a phase 1/2 clinical trial to test MSC exosomes in patients with osteochondral lesions.

Cell-based therapy using Mesenchymal Stromal Cell (MSC) has generally been efficacious in treating a myriad of diseases in animal models and clinical trials. The rationale for MSC therapy was predicated on the potential of MSC to differentiate and form new replacement cells in the diseased tissue. However, pre-clinical animal and clinical data were more consistent with a secretion- and not a differentiation-based rationale. Analysis of MSC secretion led to the identification of small extracellular vesicles (sEVs) as therapeutically active, secretory agents. MSC-sEVs are defined as bi-lipid membrane vesicles of 50-200 nm in diameter that are secreted by MSCs. They reportedly exert similar therapeutic efficacy as MSCs in many diseases including neurological diseases. MSC-sEVs being small and non-living are intrinsically safer than living MSCs. Manufacturing of MSC-sEVs may also be less complex. Nevertheless, realising the therapeutic potential of MSC-sEVs will require exacting scientific rigor and robustness, as well as compliance to regulatory oversight. This review summarises the scientific rationale for the transition of MSC therapy from a cell- to an EV-based therapy and discusses critical scientific issues in the development of MSC-sEVs therapy., (Copyright © 2021 Elsevier Inc. All rights reserved.)

BACKGROUND: Because health plans each issue their own policies, drug coverage can vary. This variation can result in patients having unequal access to treatment. In this study, we evaluate commercial health plans' coverage policies for erythropoiesis-stimulating agents (ESAs) for patients with anemia resulting from chronic kidney disease (CKD). OBJECTIVES: To assess how a set of US commercial health plans cover ESAs for patients with anemia due to CKD. Our second objective was to examine the evidence that the plans reviewed when formulating their coverage policies. METHODS: We used the Tufts Medical Center Specialty Drug and Evidence and Coverage Database to identify coverage policies issued by 17 of the largest US commercial health plans for ESAs. The following drugs were indicated for anemia due to CKD: darbepoetin alfa, methoxy polyethylene glycol-epoetin beta, epoetin alfa (available as two brands), and epoetin alfa-epbx. Coverage policies were current as of May 2019. We determined whether the health plans applied any restrictions, such as step therapy protocols or patient subgroup restrictions, in their coverage policies. We categorized the evidence that plans cited to support their policies into seven categories: randomized controlled trials (RCTs), real-world evidence (RWE) studies (studies based on data collected in a real-world setting), other clinical studies (eg, single arm trials), systematic reviews and/or meta-analyses, clinical or treatment guidelines, health technology assessments, and economic evaluations. RESULTS: We categorized 72.5% of coverage policies (58/80 policies) as equivalent to the FDA label and 27.5% (22/80 policies) as more restrictive. In restricted policies, plans most often applied step therapy protocols (18/22 policies), followed by prescriber requirements (4/22 policies), and patient subgroup restrictions (3/22 policies). Five health plans applied restrictions in at least half of their coverage policies; seven plans did not apply restrictions in any policy. Plans that cited evidence reviewed an average of 10 citations across their ESA coverage policies, ranging from one to 29 studies. Plans varied with respect to the types of cited studies: at least 50% of evidence cited by five health plans was RCTs, while half or more of the evidence cited by four health plans was clinical or treatment guidelines. CONCLUSIONS: Health plans varied in how they covered ESAs for patients with anemia due to CKD and in the evidence cited in their coverage policies. Inconsistencies in plans' coverage policies may have implications for patients' access to ESAs. DISCLOSURES: This study was funded by Otsuka Pharmaceutical Development and Commercialization. Sanon, Redmond, and Mogahadam are employed by Otsuka Pharmaceutical. Michalopoulos was employed by Otsuka Pharmaceutical at the time of this study. Margaretos, Panzer, and Chambers are employed by Tufts Medical Center, Institute for Clinical Research and Health Policy Studies, Center for the Evaluation of Value and Risk in Health. Lai was with Tufts Medical Center, Institute for Clinical Research and Health Policy Studies, Center for the Evaluation of Value and Risk in Health at the time of this study.

Mesenchymal stromal/stem cells (MSCs) have been widely tested against many diseases, with more than 1000 registered clinical trials worldwide. Despite many setbacks, MSCs have been approved for the treatment of graft-versus-host disease and Crohn disease. However, it is increasingly clear that MSCs exert their therapeutic functions in a paracrine manner through the secretion of small extracellular vesicles (sEVs) of 50-200 nm in diameter. Unlike living cells that can persist long-term, sEVs are non-living and non-replicative and have a transient presence in the body. Their small size also renders sEV preparations highly amenable to sterilization by filtration. Together, acellular MSC-sEV preparations are potentially safer and easier to translate into the clinic than cellular MSC products. Nevertheless, there are inherent challenges in the development of MSC-sEV drug products. MSC-sEVs are products of living cells, and living cells are sensitive to changes in the external microenvironment. Consequently, quality control metrics to measure key identity and potency features of MSC-sEV preparations have to be specified during development of MSC-sEV therapeutics. The authors have previously described quantifiable assays to define the identity of MSC-sEVs. Here the authors discuss requirements for prospective potency assays to predict the therapeutic effectiveness of the drug substance in accordance with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. Although potency assays should ideally reflect the mechanism of action (MoA), this is challenging because the MoA for the reported efficacy of MSC-sEV preparations against multiple diseases of diverse underlying pathology is likely to be complex and different for each disease and difficult to fully elucidate. Nevertheless, robust potency assays could be developed by identifying the EV attribute most relevant to the intended biological activity in EV-mediated therapy and quantifying the EV attribute. Specifically, the authors highlight challenges and mitigation measures to enhance the manufacture of consistent and reproducibly potent sEV preparations, to identify and select the appropriate EV attribute for potency assays despite a complex "work-in-progress" MoA and to develop assays likely to be compliant with regulatory guidance for assay validation., (Copyright © 2021 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Background: We aim to assess the learning curve of robotic portal lobectomy with four arms (RPL-4) in patients with pulmonary neoplasms using prospectively collected data., Methods: Data from 100 consecutive cases with lung neoplasms undergoing RPL-4 were prospectively accumulated into a database between June 2018 and August 2019. The Da Vinci Si system was used to perform RPL-4. Regression curves of cumulative sum analysis (CUSUM) and risk-adjusted CUSUM (RA-CUSUM) were fit to identify different phases of the learning curve. Clinical indicators and patient characteristics were compared between different phases., Results: The mean operative time, console time, and docking time for the entire cohort were 130.6 ± 53.8, 95.5 ± 52.3, and 6.4 ± 3.0 min, respectively. Based on CUSUM analysis of console time, the surgical experience can be divided into three different phases: 1-10 cases (learning phase), 11-51 cases (plateau phase), and >51 cases (mastery phase). RA-CUSUM analysis revealed that experience based on 56 cases was required to truly master this technique. Total operative time (p < 0.001), console time (p < 0.001), and docking time (p = 0.026) were reduced as experience increased. However, other indicators were not significantly different among these three phases., Conclusions: The RPL-4 learning curve can be divided into three phases. Ten cases were required to pass the learning curve, but the mastery of RPL-4 for satisfactory surgical outcomes requires experience with at least 56 cases., (© 2021 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Mesenchymal-stem/stromal-cell-derived small extracellular vesicles (MSC-sEV) have been shown to ameliorate many diseases in preclinical studies. However, translating MSC-sEV into clinical use requires the development of scalable manufacturing processes for highly reproducible preparations of safe and potent MSC-sEVs. A major source of variability in MSC-sEV preparations is EV producer cells. To circumvent variability in producer cells, clonal immortalized MSC lines as EV producer lines are increasingly being used for sEV production. The use of sEVs from immortalized producer cells inevitably raises safety concerns regarding the tumorigenicity or tumor promoting potential of the EV products. In this study, cells from E1-MYC line, a MSC cell line immortalized with the MYC gene, were injected subcutaneously into athymic nude mice. At 84 days post-injection, no tumor formation was observed at the injection site, lungs, or lymph nodes. E1-MYC cells pre-and post-sEV production did not exhibit anchorage-independent growth in soft agar. Daily intraperitoneal injections of 1 or 5 μg sEVs from E1-MYC into athymic nude mice with FaDu human head and neck cancer xenografts for 28 days did not promote or inhibit tumor growth relative to the xenograft treated with vehicle control. Therefore, MYC -immortalized MSCs are not tumorigenic and sEVs from these MSCs do not promote tumor growth.

Aging drives progressive loss of the ability of tissues to recover from stress, partly through loss of somatic stem cell function and increased senescent burden. We demonstrate that bone marrow-derived mesenchymal stem cells (BM-MSCs) rapidly senescence and become dysfunctional in culture. Injection of BM-MSCs from young mice prolonged life span and health span, and conditioned media (CM) from young BM-MSCs rescued the function of aged stem cells and senescent fibroblasts. Extracellular vesicles (EVs) from young BM-MSC CM extended life span of Ercc1 -/- mice similarly to injection of young BM-MSCs. Finally, treatment with EVs from MSCs generated from human ES cells reduced senescence in culture and in vivo, and improved health span. Thus, MSC EVs represent an effective and safe approach for conferring the therapeutic effects of adult stem cells, avoiding the risks of tumor development and donor cell rejection. These results demonstrate that MSC-derived EVs are highly effective senotherapeutics, slowing the progression of aging, and diseases driven by cellular senescence., (© 2021 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.)

Effective treatments for patients suffering from heat hypersensitivity are lacking, mostly due to our limited understanding of the pathogenic mechanisms underlying this disorder. In the nervous system, activating transcription factor 4 (ATF4) is involved in the regulation of synaptic plasticity and memory formation. Here, we show that ATF4 plays an important role in heat nociception. Indeed, loss of ATF4 in mouse dorsal root ganglion (DRG) neurons selectively impairs heat sensitivity. Mechanistically, we show that ATF4 interacts with transient receptor potential cation channel subfamily M member-3 (TRPM3) and mediates the membrane trafficking of TRPM3 in DRG neurons in response to heat. Loss of ATF4 also significantly decreases the current and KIF17-mediated trafficking of TRPM3, suggesting that the KIF17/ATF4/TRPM3 complex is required for the neuronal response to heat stimuli. Our findings unveil the non-transcriptional role of ATF4 in the response to heat stimuli in DRG neurons.

Abstract: Mechanical allodynia is a debilitating condition for millions of patients with chronic pain. Mechanical allodynia can manifest in distinct forms, including brush-evoked dynamic and filament-evoked static allodynia. In the nervous system, the forkhead protein Foxo1 plays a critical role in neuronal structures and functions. However, the role of Foxo1 in the somatosensory signal remains unclear. Here, we found that Foxo1 selectively regulated static mechanical pain. Foxo1 knockdown decreased sensitivity to static mechanical stimuli in normal rats and attenuated static mechanical allodynia in rat models for neuropathic, inflammatory, and chemotherapy pain. Conversely, Foxo1 overexpression selectively enhanced sensitivity to static mechanical stimuli and provoked static mechanical allodynia. Furthermore, Foxo1 interacted with voltage-gated sodium Nav1.7 channels and increased the Nav1.7 current density by accelerating activation rather than by changing the expression of Nav1.7 in dorsal root ganglia neurons. In addition, the serum level of Foxo1 was found to be increased in chronic pain patients and to be positively correlated with the severity of chronic pain. Altogether, our findings suggest that serum Foxo1 level could be used as a biological marker for prediction and diagnosis of chronic pain. Moreover, selective blockade of Foxo1/Nav1.7 interaction may offer a new therapeutic approach in patients with mechanical pain., (Copyright © 2020 International Association for the Study of Pain.)

Severe psoriasis, a chronic inflammatory skin disease is increasingly being effectively managed by targeted immunotherapy but long-term immunotherapy poses health risk and loss of response. Therefore, there is a need for alternative therapy strategies. Mesenchymal stem/stromal cell (MSC) exosomes are widely known for their potent immunomodulatory properties. Here we investigated if topically applied MSC exosomes could alleviate psoriasis-associated inflammation. Topically applied fluorescent exosomes on human skin explants were confined primarily to the stratum corneum with <1% input fluorescence exiting the explant over a 24-h period. Nevertheless, topically applied MSC exosomes in a mouse model of imiquimod (IMQ) psoriasis significantly reduced IL-17 and terminal complement activation complex C5b-9 in the mouse skin. MSC exosomes were previously shown to inhibit complement activation, specifically C5b-9 complex formation through CD59. Infiltration of neutrophils into the stratum corneum is characteristic of psoriasis and neutrophils are a major cellular source of IL-17 in psoriasis through the release of neutrophil extracellular traps (NETs). We propose that topically applied MSC exosomes inhibit complement activation in the stratum corneum and this alleviates IL-17 release by NETS from neutrophils that accumulate in and beneath the stratum corneum.

Background: US commercial health plans have been found to vary in how they cover specialty drugs indicated for a range of diseases. In this study, we examined patients' access to hemophilia A (HemA) treatments across a set of large commercial health plans., Objective: To examine variation in health plans' coverage policies for HemA treatments., Methods: We reviewed HemA treatment coverage policies (current as of August 2019) issued by 17 commercial health plans primarily using the Tufts Medical Center Specialty Drug Evidence and Coverage Database. We categorized policies as: covered without conditions (coverage consistent with the FDA label); covered with conditions (conditions on coverage beyond the FDA label); broader coverage (coverage for a broader patient population than the FDA label); and mixed (conditions on coverage beyond the FDA label in one way, but coverage was broader than the FDA label in another)., Results: We identified 296 coverage policies for 26 HemA treatments, including 15 short half-life factor VIII (FVIII) products, five extended half-life FVIII products, three bypassing agents, two desmopressin products, and emicizumab. We classified 36% of policies as coverage without conditions, 50% as covered with conditions , 7% as broader coverage , and 7% as mixed . Plans applied conditions on coverage with different frequencies: two did not apply conditions in any policies; ten applied conditions in ≥50%; four applied conditions in <40%. One plan did not publish coverage policies for any HemA products. Conditions on coverage most often related to bleeding frequency (36%), although specific requirements varied. Plans applied step therapy protocols in 17% of policies., Conclusions: How health plans covered HemA treatments varied. Plans added conditions on coverage beyond the FDA label roughly half the time. Conditions most often related to bleeding frequency. Variable coverage affects patients' access to treatment, and potentially has clinical implications on disease management and disease progression.

The observations that mesenchymal stem cells (MSCs) exert cardiac protection and repair via their secretome with the active component(s) identified as exosomes underpinned our test of the efficacy of MSC exosomes in a porcine model of myocardial infarction (MI) when administered systemically by the convenient method of intravenous (IV) bolus injection. Results show that 7 days of IV exosomes results in clear reduction (30-40%) of infarct size measured at both 7 and 28 days post-MI, despite near identical release of hs Troponin T. Together with reduced infarct size, exosome treatment reduced transmurality and lessened wall thinning in the infarct zone. Exosome treated pigs showed relative preservation of LV function with significant amelioration of falls in fractional wall thickening compared with control. However, global measures of LV function were less protected by exosome treatment. It is possible that greater preservation of global LV function may have been attenuated by increased cardiac fibrosis, as T1 values showed significant increase in the exosome pigs compared to control particularly in the infarct related segments. Taken together, these results show clear effects of IV exosomes administered over 7 days to reduce infarct size with relatively preserved cardiac function compared to control treated infarct pigs., (Copyright © 2020 Charles, Li, Yeung, Mazlan, Lai, de Kleijn, Lim and Richards.)

Purpose: To examine the RWE U.S. commercial health plans cite in their specialty drug coverage decisions., Methods: We used the Tufts Medical Center Specialty Drug Evidence and Coverage Database to identify specialty drug coverage decisions (n = 7267) issued by 17 large commercial health plans. We categorized the clinical evidence plans cited in these coverage decisions (n = 5227) as randomized controlled trials (RCTs), RWE studies, and other clinical studies (studies other than RCT or RWE study). We categorized RWE studies with respect to study type, for example, case series, studies based on medical records, and so on. We compared the frequency that plans cited different categories of RWE, cited RWE for different diseases, and cited RWE for drugs on the market for different time periods., Results: RWE comprised 16% of cited clinical studies. Health plans cited RWE with different frequencies (5%-31% of the cited clinical evidence). Overall, plans cited RWE categorized as medical records most often (26% of cited RWE studies). Plans varied in the frequency they cited different RWE categories. Plans most frequently cited RWE for gastroenterological diseases (35% of clinical study citations) and least frequently for respiratory diseases (11% of clinical study citations). Plans cited RWE more for drugs that have long been on the market., Conclusions: Health plans varied with respect to the number and types of RWE studies they cited in their specialty drug coverage decisions. Plans cited RWE more often for some diseases than others, and cited more RWE for older drugs., (© 2020 John Wiley & Sons Ltd.)

Purpose: To compare the efficacy of mesenchymal stem cell (MSC) exosomes with hyaluronic acid (HA) against HA alone for functional cartilage regeneration in a rabbit osteochondral defect model., Methods: Critical-size osteochondral defects (4.5-mm diameter and 1.5-mm depth) were created on the trochlear grooves in the knees of 18 rabbits and were randomly allocated to 2 treatment groups: (1) exosomes and HA combination and (2) HA alone. Three 1-mL injections of either exosomes and HA or HA alone were administered intra-articularly immediately after surgery and thereafter at 7 and 14 days after surgery. At 6 and 12 weeks, gross evaluation, histologic and immunohistochemical analysis, and scoring were performed. The functional biomechanical competence of the repaired cartilage also was evaluated., Results: Compared with defects treated with HA, defects treated with exosomes and HA showed significant improvements in macroscopic scores (P = .032; P = .001) and histologic scores (P = .005; P < .001) at 6 and 12 weeks, respectively. Defects treated with exosomes and HA also demonstrated improvements in mechanical properties compared with HA-treated defects, with significantly greater Young's moduli (P < .05) and stiffness (P < .05) at 6 and 12 weeks. By 12 weeks, the newly-repaired tissues in defects treated with exosomes and HA composed mainly of hyaline cartilage that are mechanically and structurally superior to that of HA-treated defects and demonstrated mechanical properties that approximated that of adjacent native cartilage (P > .05). In contrast, HA-treated defects showed some repair at 6 weeks, but this was not sustained, as evidenced by significant deterioration of histologic scores (P = .002) and a plateau in mechanical properties from 6 to 12 weeks., Conclusions: This study shows that the combination of MSC exosomes and HA administered at a clinically acceptable frequency of 3 intra-articular injections can promote sustained and functional cartilage repair in a rabbit post-traumatic cartilage defect model, when compared with HA alone., Clinical Relevance: Human MSC exosomes and HA administered in combination promote functional cartilage repair and may represent a promising cell-free therapy for cartilage repair in patients., (Copyright © 2020 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Background: Excessive intraoperative hemorrhage is a critical factor of poor prognoses after hepatectomy. Low central venous pressure during parenchymal transection is recognized to effectively reduce intraoperative hemorrhage in open procedures. However, the role of controlled low central venous pressure in laparoscopic hepatectomy is still controversial., Methods: In the present randomized clinical trial, we set up a standard boundary of low central venous pressure according to our Pilot Study, then enrolled patients scheduled for elective laparoscopic hepatectomy and allocated them randomly to a group undergoing central venous pressure reduction by anesthesiologic interventions or a control group. The primary efficacy endpoint was total intraoperative blood loss and perioperative adverse events. Analyses were performed following the intention-to-treat principle, and patients and surgeons were blinded (ClinicalTrials.gov, Number: NCT03422913)., Results: Between January 2017 and October 2018, 146 out of 469 patients were randomized and eligible for inclusion in the final analyses. Based on the retrospective training cohort, we set a central venous pressure of 5 cm H 2 O as a cutoff value (standard low central venous pressure). Compared with patients in the control group, those in the controlled low central venous pressure group had a significantly lower central venous pressure during resection (4.83 ± 3.41 cm H 2 O vs 9.26 ± 3.38 cm H 2 O; P < .001) and significantly reduced total intraoperative blood loss (188.00 ± 162.00 mL vs 346.00 ± 336.00 mL; P < .001). The perioperative adverse events were comparable in both study groups (P = .313)., Conclusion: The safety and efficacy of controlled low central venous pressure were demonstrated in complex laparoscopic hepatectomy for the first time by our study, and this technique is recommended to be applied routinely in laparoscopic hepatectomy., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Surgical resection of primary solid tumor under anesthesia remains a common practice. It has been concerned whether general anesthetics, especially volatile anesthetics, may promote the growth, migration, and invasion of cancer cells. In this study, we examined the effects of sevoflurane on human glioblastoma cells and determined the role of cluster of differentiation (CD) 44, a cell surface protein involved in cell growth, migration, and invasion, in sevoflurane's effects. We showed that exposure to 1%-4% sevoflurane did not change the cell proliferation, but concentration-dependently increased the invasion of human glioblastoma U251 cells. Furthermore, 4% sevoflurane significantly increased the migration and colony-forming ability of U251 cells. Similar results were observed in human glioblastoma A172 cells. Exposure to sevoflurane concentration-dependently increased the activity of calpains, a group of cysteine proteinases, and CD44 protein in U251 and A172 cells. Knockdown of CD44 with siRNA abolished sevoflurane-induced increases in calpain activity, migration, invasion, and colony-forming ability of U251 cells. Inhalation of 4% sevoflurane significantly increased the tumor volume and invasion/migration distance of U87 cells from the tumor mass in the nude mice bearing human glioblastoma U87 xenograft in the brain. The aggravation by sevoflurane was attenuated by CD44 silencing. In conclusion, sevoflurane increases the migration, invasion, and colony-forming ability of human glioblastoma cells in vitro, and their tumor volume and invasion/migration in vivo. Sevoflurane enhances these cancer cell biology features via increasing the expression of CD44.

Lanosterol synthase( LS) is a key enzyme involving in the mevalonate pathway( MVA pathway) to produce lanosterol,which is a precursor of ganoderma triterpenoid. And the transcriptional regulation of LS gene directly affects the content of triterpenes in Ganoderma lucidum. In order to study the transcriptional regulation mechanism of LS gene,yeast one-hybrid technique was used to screen the transcription regulators which interact withthe promoter of LS. The bait vector was constructed by LS promoter,then the vector was transformed yeast cells to construct bait yeast strain. One-hybrid c DNA library was constructed via SMART technology. Then the c DNA and p GADT7-Rec vector were co-transformed into the bait yeast strain to screen the upstream regulatory factors of the promoter region of LS by homologous recombination. Total of 23 positive clones were screened. After sequencing,blast was performed against the whole-genome sequence of G. lucidum. As a result,8 regulatory factors were screened out including the transcription initiation TFIIB,the alpha/beta hydrolase super family,ALDH-SF superfamily,60 S ribosomal protein L21,ATP synthase β-subunit,microtubule associated protein Cript,prote asome subunit β-1,and transaldolase. Until now,the regulation effect of these 8 regulatory factors in G.lucidum has not been reported. This study provides candidate proteins for in-depth study on the expression regulation of LS.

Objectives: Our goal was to investigate the incidence and distribution of mediastinal lymph node metastases (MLNM) in non-small-cell lung cancers (NSCLC) 3 cm or less, with the purpose of guiding mediastinal lymph node dissection., Methods: A total of 2292 cases seen between January 2001 and December 2014 were included. These patients were grouped according to the lobes with the primary tumours. The incidence and distribution of pathological MLNM were compared among the groups. The impact of MLNM on overall survival was also compared., Results: The most common mediastinal metastatic sites for different primary tumour lobes were as follows: right upper lobe, 17.7% (87/492) for level 4R; right middle lobe, 14.9% (28/188) for level 7; right lower lobe, 19.8% (82/414) for level 7; left upper lobe, 18.2% (96/528) for level 5; and left lower lobe, 16.6% (42/253) for level 7. For patients with tumours in the upper lobe, the median survival time was 32 months for those with MLNM in the subcarinal zone or lower zone compared with 83 months for those with MLNM only in the upper zone (P < 0.01). When the tumours were 1 cm or less, the incidence of MLNM to the lower zone for upper lobe tumours and of MLNM to the upper zone for lower lobe tumours was zero., Conclusions: Different primary NSCLC lobe locations have a different propensity to be sites of MLNM for those tumours that are 3 cm or less. For tumours no larger than 1 cm, a lower zone mediastinal lymph node dissection might be unnecessary for upper lobe tumours and an upper zone mediastinal lymph node dissection might be unnecessary for lower lobe tumours., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Small extracellular vesicles (sEVs) from mesenchymal stromal/stem cells (MSCs) are transiting rapidly towards clinical applications. However, discrepancies and controversies about the biology, functions, and potency of MSC-sEVs have arisen due to several factors: the diversity of MSCs and their preparation; various methods of sEV production and separation; a lack of standardized quality assurance assays; and limited reproducibility of in vitro and in vivo functional assays. To address these issues, members of four societies (SOCRATES, ISEV, ISCT and ISBT) propose specific harmonization criteria for MSC-sEVs to facilitate data sharing and comparison, which should help to advance the field towards clinical applications. Specifically, MSC-sEVs should be defined by quantifiable metrics to identify the cellular origin of the sEVs in a preparation, presence of lipid-membrane vesicles, and the degree of physical and biochemical integrity of the vesicles. For practical purposes, new MSC-sEV preparations might also be measured against a well-characterized MSC-sEV biological reference. The ultimate goal of developing these metrics is to map aspects of MSC-sEV biology and therapeutic potency onto quantifiable features of each preparation.

Mesenchymal stem cells (MSCs) are potential therapeutics for the treatment of periodontal defects. It is increasingly accepted that MSCs mediate tissue repair through secretion of trophic factors, particularly exosomes. Here, we investigated the therapeutic effects of human MSC exosome-loaded collagen sponge for regeneration of surgically created periodontal intrabony defects in an immunocompetent rat model. We observed that relative to control rats, exosome-treated rats repaired the defects more efficiently with regeneration of periodontal tissues including newly-formed bone and periodontal ligament (PDL). We also observed that concomitant with this, there was increased cellular infiltration and proliferation. We therefore postulated that MSC exosomes enhanced regeneration through increased cellular mobilisation and proliferation. Using PDL cell cultures, we demonstrated that MSC exosomes could increase PDL cell migration and proliferation through CD73-mediated adenosine receptor activation of pro-survival AKT and ERK signalling. Inhibition of AKT or ERK phosphorylation suppressed PDL cell migration and proliferation. Our findings demonstrated for the first time that MSC exosomes enhance periodontal regeneration possibly by increasing PDL migration and proliferation. This study suggests that MSC exosome is a viable ready-to-use and cell-free MSC therapeutic for the treatment of periodontal defects. STATEMENT OF SIGNIFICANCE: Mesenchymal stem cell (MSC) therapies have demonstrated regenerative potential for the treatment of periodontal defects. However, translation of cellular therapies is hampered by challenges in maintaining optimal cell vitality and viability from manufacturing and storage to final delivery to patients. Although the use of MSCs for tissue repair was first predicated on their differentiation potential, the therapeutic efficacy of MSCs has increasingly been attributed to its paracrine secretion, particularly exosomes or small extracellular vesicles. In this study, MSC exosome-loaded collagen sponge enhanced periodontal regeneration in an immunocompetent rat periodontal defect model without any obvious adverse effects. These findings provide the basis for future development of MSC exosomes as a cell-free strategy for periodontal regeneration., (Copyright © 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The efficacy of mesenchymal stem cell (MSC) therapies is increasingly attributed to paracrine secretion, particularly exosomes. In this study, we investigated the role of MSC exosomes in the regulation of inflammatory response, nociceptive behaviour, and condylar cartilage and subchondral bone healing in an immunocompetent rat model of temporomandibular joint osteoarthritis (TMJ-OA). We observed that exosome-mediated repair of osteoarthritic TMJs was characterized by early suppression of pain and degeneration with reduced inflammation, followed by sustained proliferation and gradual improvements in matrix expression and subchondral bone architecture, leading to overall joint restoration and regeneration. Using chondrocyte cultures, we could attribute some of the cellular activities during exosome-mediated joint repair to adenosine activation of AKT, ERK and AMPK signalling. Specifically, MSC exosomes enhanced s-GAG synthesis impeded by IL-1β, and suppressed IL-1β-induced nitric oxide and MMP13 production. These effects were partially abrogated by inhibitors of adenosine receptor activation, AKT, ERK and AMPK phosphorylation. Together, our observations suggest that MSC exosomes promote TMJ repair and regeneration in OA through a well-orchestrated mechanism of action that involved multiple cellular processes to restore the matrix and overall joint homeostasis. This study demonstrates the translational potential of a cell-free ready-to-use exosome-based therapeutic for treating TMJ pain and degeneration., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.

The therapeutic efficacy of mesenchymal stromal cells (MSCs), multipotent progenitor cells, is attributed to small (50-200 nm) extracellular vesicles (EVs). The presence of a lipid membrane differentiates exosomes and EVs from other macromolecules. Analysis of this lipid membrane revealed three distinct small MSC EV subtypes, each with a differential affinity for cholera toxin B chain (CTB), annexin V (AV), and Shiga toxin B chain (ST) that bind GM1 ganglioside, phosphatidylserine, and globotriaosylceramide, respectively. Similar EV subtypes are also found in biologic fluids and are independent sources of disease biomarkers. Here, we compare and contrast these three EV subtypes. All subtypes carry β-actin, but only CTB-binding EVs (CTB-EVs) are true exosomes, enriched with exosome proteins and derived from endosomes. No unique protein has been identified yet in AV-binding EVs (AV-EVs); ST-binding EVs (ST-EVs) carry RNA and a high level of extra domain A-containing fibronectin. Based on the CTB, AV, and ST subcellular binding sites, the origins of CTB-, AV-, and ST-EV biogenesis are the plasma membrane, cytoplasm, and nucleus, respectively. The differentiation of EV subtypes through membrane lipids underlies the importance of membrane lipids in defining EVs and implies an influence on EV biology and functions., (Copyright © 2019 Lai and Lim.)

Currently there is no effective treatment available for clinical patients suffering from neuropathic pain induced by chemotherapy paclitaxel. Puerarin is a major isoflavonoid extracted from the Chinese medical herb kudzu root, which has been used for treatment of cardiovascular disorders and brain injury. Here, we found that puerarin dose-dependently alleviated paclitaxel-induced neuropathic pain. At the same time, puerarin preferentially reduced the excitability and blocked the voltage-gated sodium (Na v ) channels of dorsal root ganglion (DRG) neurons from paclitaxel-induced neuropathic pain rats. Furthermore, puerarin was a more potent blocker of tetrodotoxin-resistant (TTX-R) Na v channels than of tetrodotoxin-sensitive (TTX-S) Na v channels in chronic pain rats' DRG neurons. In addition, puerarin had a stronger blocking effect on Na v 1.8 channels in DRG neurons of neuropathic pain rats and β1 subunit siRNA can abolish this selective blocking effect on Na v 1.8. Together, these results suggested that puerarin may preferentially block β1 subunit of Na v 1.8 in sensory neurons contributed to its anti-paclitaxel induced neuropathic pain effect.

Flavonoids widely found in bee products are excellent antioxidants. The structural features are important in evaluating the antiradical activity of flavonoid. In this work, the density functional theory (DFT) methods were applied to investigate the influence of C2C3 double bond on the antiradical activity of flavonoid based on three prevalently accepted radical scavenging mechanisms from the thermodynamic aspect. It is found that the hydroxyl groups in different rings are affected variously by the C2C3 double bond and the 3OH group is most influenced. For the compounds that only differ with the C2C3 double bond, the antiradical activity of flavone or flavonol (possessing C2C3 double bond) is not always stronger than that of flavanone: in the weak polarity phases, only the antiradical activities of chrysin, galangin and morin are stronger than those of pinocembrin, pinobanksin and dihydro-morin, respectively. In polar phases, the C2C3 double bond would weaken the antiradical activity of flavonoid via enlarging the proton affinity and the antiradical activity of flavone or flavonol is weaker than that of flavanone., (Copyright © 2018. Published by Elsevier Ltd.)

Mesenchymal stromal cell (MSC) therapies have demonstrated therapeutic efficacy in a wide-ranging array of tissue injury and disease indications. An important aspect of MSC-mediated therapeutic activities is immune modulation. Consistent with the concentration of MSC therapeutic potency in its secretion, a significant proportion of MSC immune potency resides in the small extracellular vesicles (sEVs) secreted by MSCs. These sEVs, which also include exosomes, carry a large cargo enriched in proteins with potent immunomodulatory activities. They have been reported to exert potent effects on humoral and cellular components of the immune system in vitro and in vivo, and may have the potential to support the diametrically opposite pro- and anti-inflammatory functions necessary for tissue repair and regeneration following injury. Following injury, pro-inflammatory activities are necessary to neutralize injury and remove dead or injured tissue, while anti-inflammatory activities to facilitate migration and proliferation of reparative cell types and to increase vascularization and nutrient supply are necessary to repair and regenerate new tissue. Therefore, a critical immunomodulatory requisite of MSC sEVs in tissue regeneration is the capacity to support the appropriate immune activities at the appropriate time. Here, we review how some of the immune regulatory targets of MSC sEVs could support the dynamic immunomodulatory activities during tissue repair and regeneration., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To observe the characteristics of positional nystagmus and clinical profile of patients with positive positional test, and to explore its possible pathogenesis. Method: One hundred and twenty-one patients with positive positional test in the vestibular function examination were enrolled in the Peking University International Hospital from January to June in 2017. According to the 2017 BPPV guidelines, patients with test positive positional nystagmus were divided into two groups: definite BPPV and the controversial syndrome. Analyses of gender, age and characteristics of nystagmus, with or without recurrent dizziness, headache, and motion sickness were undertaken between the two groups, as well as response to the repositioning maneuver. Result: Of the total 121 cases, 49 cases were diagnosed as definite BPPV, accounting for 40.5%, 72 cases as controversial syndrome, accounting for 59.5%. The proportion of women in the two group was 76.2% and 78.9%, respectively. The average age of definite BPPV and the controversial syndrome was 51.2±16.8 and 51.3±15.7, respectively.There were significant differences in nystagmus duration, spontaneous nystagmus and nystagmus after headshaking between the two groups by chi square test( P <0.01). The mean intensity of horizontal and vertical nystagmus in posterior semicircular canal BPPV was(10.2±7.4) °/s and(36.6±17.5) °/respectively. And the mean intensity of nystagmus in the strong and weak side in horizontal semicircular canal BPPV was(40.8±25.1) °/s and(20.7±11.1) °/respectively. The intensity of horizontal and vertical nystagmus of the controversial syndrome group was(7.2±7.7) °/s and(7.2±4.3) °/s respectively. The incidence of headache in the controversial syndrome group was significantly higher than that in the BPPV group, P =0.013. According to the guidelines, patients were evaluated one day after the initial treatment. The cure rate and effective rate of the definite BPPV group was 75%(36/48) and 87.5%(42/48),and was 0 and 30.4% in the controversial syndrome group respectively. Conclusion: The patients in controversial syndrome group have a preponderance of exhibiting positive nystagmus during positional test. Nystagmus were usually of low velocity and sustained. Most of these cases presented spontaneous nystagmus and headshaking induced nystagmus, as well as headache and lacunar infarctions in history, and the response to the repositioning maneuver were often poor. It may be related to vestibular migraine and central nervous system. The diagnosis of BPPV must be prudent.Both characteristics of nystagmus and medical history should be carefully analyzed to avoid overdiagnosis., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Mesenchymal stem cell (MSC) exosome specifically defines the 50-200 nm vesicles that are secreted into the extracellular space when multivesicular bodies in the MSC fuse with the plasma membrane. However, the exosome is just one of several 50-200 nm extracellular vesicles (EVs) known to be secreted by cells. Nevertheless, the term 'MSC exosome' is often used to describe populations of 50-200 nm EVs that are prepared from culture medium conditioned by MSCs on the basis that these populations collectively exhibited typical exosome-associated proteins such as endosomal proteins, TSG101 and Alix, and tetraspanin proteins, CD9, CD63 and CD81. They also carry a rich diverse RNA cargo. MSC exosomes are increasingly implicated as the mediator of many of the MSC-associated therapeutic potencies. They elicit therapeutic activity by delivering their cargo of potentially therapeutic proteins and RNAs to the recipient cells. The therapeutic potency of MSC exosomes is usually rationalized on the presence of a biologically relevant protein or RNA in the MSC exosome. In the present paper, we expanded this rationale beyond a physical presence to include biologically relevant concentration, biochemical functionality and the potential to elicit an appropriate timely biochemical response. Based on these, we propose that MSC exosomes most probably work through the protein rather than the RNA., (© 2018 The Author(s).)

Background Aims: The immunomodulatory property of mesenchymal stromal cell (MSC) exosomes is well documented. On the basis of our previous report that MSC exosomes increased regulatory T-cell (Treg) production in mice with allogenic skin graft but not in ungrafted mice, we hypothesize that an activated immune system is key to exosome-mediated Treg production., Methods: To test our hypothesis, MSC exosomes were incubated with mouse spleen CD4 + T cells that were activated with either anti-CD3/CD28 mAbs or allogenic antigen-presenting cell (APC)-enriched spleen CD11c + cells to determine whether production of mouse CD4 + CD25 + T cells or CD4 + CD25 + Foxp3 + Tregs could be induced. MSC exosomes were also administered to the lethal chimeric human-SCID mouse model of graft-versus-host disease (GVHD) in which human peripheral blood mononuclear cells were infused into irradiated NSG mice to induce GVHD., Results: We report here that MSC exosome-induced production of CD4 + CD25 + T cells or CD4 + CD25 + Foxp3 + Tregs from CD4 + T cells activated by allogeneic APC-enriched CD11C + cells but not those activated by anti-CD3/CD28 mAbs. This induction was exosome- and APC dose-dependent. In the mouse GVHD model in which GVHD was induced by transplanted human APC-stimulated human anti-mouse CD4 + T cell effectors, MSC exosome alleviated GVHD symptoms and increased survival. Surviving exosome-treated mice had a significantly higher level of human CD4 + CD25 + CD127 low/- Tregs than surviving mice treated with Etanercept, a tumor necrosis factor inhibitor., Conclusions: MSC exosome enhanced Treg production in vitro and in vivo through an APC-mediated pathway., (Copyright © 2018 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Mesenchymal stem cell (MSC) exosome was previously shown to be effective in repairing critical size osteochondral defects in an immunocompetent rat model. Here we investigate the cellular processes modulated by MSC exosomes and the mechanism of action underlying the exosome-mediated responses in cartilage repair. We observed that exosome-mediated repair of osteochondral defects was characterised by increased cellular proliferation and infiltration, enhanced matrix synthesis and a regenerative immune phenotype. Using chondrocyte cultures, we could attribute the rapid cellular proliferation and infiltration during exosome-mediated cartilage repair to exosomal CD73-mediated adenosine activation of AKT and ERK signalling. Inhibitors of AKT or ERK phosphorylation suppressed exosome-mediated increase in cell proliferation and migration but not matrix synthesis. The role of exosomal CD73 was confirmed by the attenuation of AKT and ERK signalling by AMPCP, a CD73 inhibitor and theophylline, an adenosine receptor antagonist. Exosome-treated defects also displayed a regenerative immune phenotype characterised by a higher infiltration of CD163 + regenerative M2 macrophages over CD86 + M1 macrophages, with a concomitant reduction in pro-inflammatory synovial cytokines IL-1β and TNF-α. Together, these observations demonstrated that the efficient osteochondral regeneration by MSC exosomes was effected through a coordinated mobilisation of multiple cell types and activation of several cellular processes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: The programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway inhibits the activation of T cells and plays a crucial role in the negative regulation of cellular and humoral immune responses. Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoid malignancy in adults. In the present study, we aimed to detect the expression of PD-L1 in DLBCL and to analyze its relationship with prognosis., Methods: We reviewed medical records of 204 newly diagnosed DLBCL patients in Sun Yat-sen University Cancer Center between October 2005 and August 2012. The expression of PD-L1 in tumor tissues from these 204 patients was detected using immunohistochemical (IHC) assay. The expression of anaplastic lymphoma kinase (ALK), CD5, CD30, and C-Myc in tumor specimens from 109 patients was detected using IHC, and Epstein-Barr virus (EBV)-encoded RNAs (EBERs) were detected using fluorescence in situ hybridization. The Spearman method was used for correlation analysis. The Kaplan-Meier method with log-rank test was used for univariate analysis. Cox proportional hazards model was used for multivariate analysis., Results: Of the 204 patients, 100 (49.0%) were PD-L1-positive in tumor cells and 44 (21.6%) were PD-L1-positive in tumor microenvironment. PD-L1 expression in tumor cells and tumor microenvironment were more common in the non-germinal center B-cell-like (GCB) subtype than in the GCB subtype (P = 0.02 and P = 0.04). Patients with PD-L1 expression in tumor microenvironment were more likely to be resistant to first-line chemotherapy when compared with the patients without PD-L1 expression in tumor microenvironment (P = 0.03). PD-L1 expression in tumor microenvironment was negatively correlated with C-Myc expression (r = - 0.20, P = 0.04). No correlations were detected between PD-L1 expression and the expression of ALK, CD5, and CD30 as well as EBERs. The 5-year overall survival (OS) rates were 50.0% and 67.3% in patients with and without PD-L1 expression in tumor cells (P = 0.02). PD-L1 expression in tumor cells was an independent risk predictor for OS (P < 0.01)., Conclusions: PD-L1 expression is more common in the non-GCB subtype than in the GCB subtype. PD-L1 expression in tumor microenvironment has a negative correlation with C-Myc. PD-L1 positivity predicts short survival in DLBCL patients. For patients with PD-L1 expression, more strategy such as anti-PD-L1 antibody treatment should be recommended.