CD19 CAR-expressing iPSC-derived NK cells effectively enhance migration and cytotoxicity into glioblastoma by targeting to the pericytes in tumor microenvironment

In cancer immunotherapy, chimeric antigen receptors (CARs) targeting specific antigens have become a powerful tool for cell-based therapy. CAR-natural killer (NK) cells offer selective anticancer lysis with reduced off-tumor toxicity compared to CAR-T cells, which is beneficial in the heterogeneous milieu of solid tumors. In the tumor microenvironment (TME) of glioblastoma (GBM), pericytes not only support tumor growth but also contribute to immune evasion, underscoring their potential as therapeutic targets in GBM treatment. Given this context, our study aimed to target the GBM TME, with a special focus on pericytes expressing CD19, to evaluate the potential effectiveness of CD19 CAR-iNK cells against GBM. We performed CD19 CAR transduction in induced pluripotent stem cell-derived NK (iNK) cells. To determine whether CD19 CAR targets the TME pericytes in GBM, we developed GBM-blood vessel assembloids (GBVA) by fusing GBM spheroids with blood vessel organoids. When co-cultured with GBVA, CD19 CAR-iNK cells migrated towards the pericytes surrounding the GBM. Using a microfluidic chip, we demonstrated CD19 CAR-iNK cells' targeted action and cytotoxic effects in a perfusion-like environment. GBVA xenografts recapitulated the TME including human CD19-positive pericytes, thereby enabling the application of an in vivo model for validating the efficacy of CD19 CAR-iNK cells against GBM. Compared to GBM spheroids, the presence of pericytes significantly enhanced CD19 CAR-iNK cell migration towards GBM and reduced proliferation. These results underline the efficacy of CD19 CAR-iNK cells in targeting pericytes within the GBM TME, suggesting their potential therapeutic value for GBM treatment.

Canine amniotic membrane-derived mesenchymal stem cells ameliorate atopic dermatitis through regeneration and immunomodulation

Mesenchymal stem cells (MSCs) are a promising tool for treating immune disorders. However, the immunomodulatory effects of canine MSCs compared with other commercialized biologics for treating immune disorders have not been well studied. In this study we investigated the characteristics and immunomodulatory effects of canine amnion membrane (cAM)-MSCs. We examined gene expression of immune modulation and T lymphocytes from activated canine peripheral blood mononuclear cell (PBMC) proliferation. As a result, we confirmed that cAM-MSCs upregulated immune modulation genes (TGF-β1, IDO1 and PTGES2) and suppressed the proliferation capacity of T cells. Moreover, we confirmed the therapeutic effect of cAM-MSCs compared with oclacitinib (OCL), the most commonly used Janus kinase (JAK) inhibitor, as a treatment for canine atopic dermatitis (AD) using a mouse AD model. As a result, we confirmed that cAM-MSCs with PBS treatment groups (passage 4, 6 and 8) compared with PBS only (PBS) though scores of dermatologic signs, tissue pathologic changes and inflammatory cytokines were significantly reduced. In particular, cAM-MSCs were more effective than OCL in the recovery of wound dysfunction, regulation of mast cell activity and expression level of immune modulation protein. Interestingly, subcutaneous injection of cAM-MSCs induced weight recovery, but oral administration of oclacitinib induced weight loss as a side effect. In conclusion, this study suggests that cAM-MSCs can be developed as a safe canine treatment for atopic dermatitis without side effects through effective regeneration and immunomodulation.

Preventive effects of nano-graphene oxide against Parkinson's disease via reactive oxygen species scavenging and anti-inflammation

We investigated the neuroprotective effects of deca nano-graphene oxide (daNGO) against reactive oxygen species (ROS) and inflammation in the human neuroblastoma cell line SH-SY5Y and in the 6-hydroxydopamine (6-OHDA) induced Parkinsonian rat model. An MTT assay was performed to measure cell viability in vitro in the presence of 6-OHDA and/or daNGO. The intracellular ROS level was quantified using 2',7'-dichlorofluorescein diacetate. daNGO showed neuroprotective effects against 6-OHDA-induced toxicity and also displayed ROS scavenging properties. We then tested the protective effects of daNGO against 6-OHDA induced toxicity in a rat model. Stepping tests showed that the akinesia symptoms were improved in the daNGO group compared to the control group. Moreover, in an apomorphine-induced rotation test, the number of net contralateral rotations was decreased in the daNGO group compared to the control group. By immunofluorescent staining, the animals in the daNGO group had more tyrosine hydroxylase-positive cells than the controls. By anti-Iba1 staining, 6-OHDA induced microglial activation showed a significantly decrease in the daNGO group, indicating that the neuroprotective effects of graphene resulted from anti-inflammation. In conclusion, nanographene oxide has neuroprotective effects against the neurotoxin induced by 6-OHDA on dopaminergic neurons. [BMB Reports 2023; 56(3): 202-207].

The Effect of a Novel Mica Nanoparticle, STB-MP, on an Alzheimer's Disease Patient-Induced PSC-Derived Cortical Brain Organoid Model

Alzheimer's disease (AD) is one of the most well-known neurodegenerative diseases, with a substantial amount of advancements in the field of neuroscience and AD. Despite such progress, there has been no significant improvement in AD treatments. To improve in developing a research platform for AD treatment, AD patient-derived induced pluripotent stem cell (iPSC) was employed to generate cortical brain organoids, expressing AD phenotypes, with the accumulation of amyloid-beta (Aβ) and hyperphosphorylated tau (pTau). We have investigated the use of a medical grade mica nanoparticle, STB-MP, as a treatment to decrease the expression of AD's major hallmarks. STB-MP treatment did not inhibit the expression of pTau; however, accumulated Aβ plaques were diminished in STB-MP treated AD organoids. STB-MP seemed to activate the autophagy pathway, by mTOR inhibition, and also decreased γ-secretase activity by decreasing pro-inflammatory cytokine levels. To sum up, the development of AD brain organoids successfully mimics AD phenotype expressions, and thus it could be used as a screening platform for novel AD treatment assessments.

Bioengineered liver crosslinked with nano-graphene oxide enables efficient liver regeneration via MMP suppression and immunomodulation

Decellularized extracellular matrix scaffold, widely utilized for organ engineering, often undergoes matrix decomposition after transplantation and produces byproducts that cause inflammation, leading to clinical failure. Here we propose a strategy using nano-graphene oxide to modify the biophysical properties of decellularized liver scaffolds. Notably, we demonstrate that scaffolds crosslinked with nano-graphene oxide show high resistance to enzymatic degradation via direct inhibition of matrix metalloproteinase activity and increased mechanical rigidity. We find that M2-like macrophage polarization is promoted within the crosslinked scaffolds, which reduces graft-elicited inflammation. Moreover, we show that low activities of matrix metalloproteinases, attributed to both nano-graphene oxide and tissue inhibitors of metalloproteinases expressed by M2c, can protect the crosslinked scaffolds against in vivo degradation. Lastly, we demonstrate that bioengineered livers fabricated with the crosslinked scaffolds remain functional, thereby effectively regenerating damaged livers after transplantation into liver failure mouse models. Overall, nano-graphene oxide crosslinking prolongs allograft survival and ultimately improves therapeutic effects of bioengineered livers, which offer an alternative for donor organs.

Cortical-blood vessel assembloids exhibit Alzheimer's disease phenotypes by activating glia after SARS-CoV-2 infection

A correlation between COVID-19 and Alzheimer's disease (AD) has been proposed recently. Although the number of case reports on neuroinflammation in COVID-19 patients has increased, studies of SARS-CoV-2 neurotrophic pathology using brain organoids have restricted recapitulation of those phenotypes due to insufficiency of immune cells and absence of vasculature. Cerebral pericytes and endothelial cells, the major components of blood-brain barrier, express viral entry receptors for SARS-CoV-2 and response to systemic inflammation including direct cell death. To overcome the limitations, we developed cortical-blood vessel assembloids by fusing cortical organoid with blood vessel organoid to provide vasculature to brain organoids a nd obtained the characteristics of increased expression of microglia and astrocytes in brain organoids. Furthermore, we observed AD pathologies, including β-amyloid plaques, which were affected by the inflammatory response from SARS-CoV-2 infection. These findings provide an advanced platform to investigate human neurotrophic diseases, including COVID-19, and suggest that neuroinflammation caused by viral infection facilitates AD pathology.

Anti-apoptotic Splicing Variant of AIMP2 Recover Mutant SOD1-Induced Neuronal Cell Death

Although a couple of studies have reported that mutant superoxide dismutase 1 (SOD1), one of the causative genes of familial amyotrophic lateral, interacts physically with lysyl-tRNA synthetase (KARS1) by a gain of function, there is limited evidence regarding the detailed mechanism about how the interaction leads to neuronal cell death. Our results indicated that the aminoacyl-tRNA synthetase-interacting multi-functional protein 2 (AIMP2) mediated cell death upon the interplay between mutant SOD1 and KARS1 in ALS. Binding of mutant SOD1 with KARS1 led to the release of AIMP2 from its original binding partner KARS1, and the free form of AIMP2 induced TRAF2 degradation followed by TNF-α-induced cell death. We also suggest a therapeutic application that overexpression of DX2, the exon 2-deleted antagonistic splicing variant of AIMP2 (AIMP2-DX2), reduced neuronal cell death in the ALS mouse model. Expression of DX2 suppressed TRAF2 degradation and TNF-α-induced cell death by competing mode of action against full-length AIMP2. Motor neuron differentiated form iPSC showed a resistance in neuronal cell death after DX2 administration. Further, intrathecal administration of DX2-coding adeno-associated virus (AAV) improved locomotive activity and survival in a mutant SOD1-induced ALS mouse model. Taken together, these results indicated that DX2 could prolong life span and delay the ALS symptoms through compensation in neuronal inflammation.

Combined Orobol-Bentonite Composite Formulation for Effective Topical Skin Targeted Therapy in Mouse Model

Purpose

Orobol is an isoflavone that has a potent skin protection effect. The objective of this study was to prepare a novel bentonite-based composite formulation of orobol to enhance topical skin delivery.

Methods

The composition was optimized based on the orobol content in the composite and the in vitro release studies, followed by the in vitro and in vivo hairless mouse skin deposition studies. Physicochemical characterizations of the composite formulation were performed by powder X-ray refractometry (XRD) and scanning electron microscopy (SEM). The in vitro cytotoxicity and in vivo toxicity studies were conducted in human keratinocytes and in hairless mouse, respectively.

Results and Discussions

The in vitro release of orobol from the bentonite composites was higher than that from the suspension, which was further increased with the addition of phosphatidylcholine. The composite formulation significantly enhanced the in vitro and in vivo skin deposition of orobol in hairless mouse skin compared to the orobol suspension. Moreover, the addition of phosphatidyl choline not only improved the dissolution and incomplete release of orobol from the bentonite composite but also enhanced the deposition of orobol in the skin. XRD histograms and SEM images confirmed that the enhanced dissolution of orobol from the composite was attributed to its amorphous state on bentonite. The in vitro and in vivo toxicity studies support the safety and biocompatibility of the orobol-loaded bentonite composite formulation.

Conclusion

These findings suggest that the orobol-loaded bentonite composite formulation could be a potential topical skin delivery system for orobol.

LC-MS/MS-based serum proteomics reveals a distinctive signature in a rheumatoid arthritis mouse model after treatment with mesenchymal stem cells

Mesenchymal stem cells (MSCs) are known to be able to modulate immune responses, possess tissue-protective properties, and exhibit healing capacities with therapeutic potential for various diseases. The ability of MSCs to secrete various cytokines and growth factors provides new insights into autoimmune-diseases such as rheumatoid arthritis (RA). RA is a systemic autoimmune disease that affects the lining of synovial joints, causing stiffness, pain, inflammation, and joint erosion. In recent years, MSCs-based therapies have been widely proposed as promising therapies in the treatment of RA. However, the mechanism involved in disease-specific therapeutic effects of MSCs on RA remains unclear. To clarify the mechanism involved in effects of MSCs on RA, proteomic profiling was performed using an RA mouse model before and after treatment with MSCs. In this study, treatment efficacy of human umbilical cord blood-mesenchymal stem cells (hUCB-MSCs) was confirmed using a type II collagen-induced arthritis (CIA) mouse model. Results of measuring incidence rates of arthritis and clinical arthritis index (CAI) revealed that mice administrated with hUCB-MSCs had a significant reduction in arthritis severity. Proteins that might affect disease progression and therapeutic efficacy of hUCB-MSC were identified through LC-MS/MS analysis using serum samples. In addition, L-1000 analysis was performed for hUCB-MSC culture medium. To analysis data obtained from LC–MS/MS and L-1000, tools such as ExDEGA, MEV, and DAVID GO were used. Results showed that various factors secreted from hUCB-MSCs might play roles in therapeutic effects of MSCs on RA, with platelet activation possibly playing a pivotal role. Results of this study also suggest that SERPINE1 and THBS1 among substances secreted by hUCB-MSC might be key factors that can inhibit platelet activation. This paper is expected to improve our understanding of mechanisms involved in treatment effects of stem cells on rheumatoid arthritis.

Wnt-activating human skin organoid model of atopic dermatitis induced by Staphylococcus aureus and its protective effects by Cutibacterium acnes

A recently developed human PSC-derived skin organoid model has opened up new avenues for studying skin development, diseases, and regeneration. The current model has limitations since the generated organoids are enclosed, circular aggregates with an inside-out morphology with unintended off-target development of cartilage. Here, we first demonstrated that Wnt signaling activation resulted in larger organoids without off-target cartilage. We optimized further using an air-liquid interface (ALI) culture method to recapitulate structural features representative of human skin tissue. Finally, we used the ALI-skin organoid platform to model atopic dermatitis by Staphylococcus aureus (SA) colonization and infection. SA infection led to a disrupted skin barrier and increased production of epidermal- and dermal-derived inflammatory cytokines. Additionally, we found that pre-treatment with Cutibacterium acnes had a protective effect on SA-infected organoids. Thus, this ALI-skin organoid platform may be a useful tool for modeling human skin diseases and evaluating the efficacy of novel therapeutics.

•

Wnt signaling activation results in larger organoids without off-target cartilage

•

Air-liquid interface culture is used to recapitulate human skin tissue structure

•

S. aureus infection damaged the skin barrier and elevated inflammatory cytokines

•

Pre-treated Cutibacterium acnes had a protective effect on Staphylococcus aureus-infected organoids

Enhanced delivery to brain using sonosensitive liposome and microbubble with focused ultrasound

Glioblastoma is considered one of the most aggressive and dangerous brain tumors. However, treatment of GBM has been still challenged due to blood-brain barrier (BBB). BBB prevents that the chemotherapeutic molecules are extravasated to brain. In this study, sonosensitive liposome encapsulating doxorubicin (DOX) was developed for enhancement of GBM penetration in combination with focused ultrasound (FUS) and microbubbles. Upon ultrasound (US) irradiation, microbubbles induce cavitation resulting in the tight junction of BBB endothelium to temporarily open. In addition, the composition of sonosensitive liposome was optimized by comparison of sonosensitivity and intracellular uptake to U87MG cells. The optimal sonosensitive liposome, IMP301-DC, resulted 123.9 ± 38.2 nm in size distribution and 98.2 % in loading efficiency. Related to sonosensitivity of IMP301-DC, US-triggered release ratio of doxorubicin was 69.2 ± 12.3 % at 92 W/cm² of US intensity for 1 min. In the in vivo experiments, the accumulation of DiD fluorescence probe labeled IMP301-DC-shell in the brain through the BBB opening was increased more than two-fold compared to that of Doxil-shell, non-sonosensitive liposome. US exposure significantly increased GBM cytotoxicity of IMP301-DC. In conclusion, this study demonstrated that IMP301-DC could serve as an alternative solution to enhance the penetration to GBM treatment via BBB opening by non-invasive FUS combined with microbubbles.

All-in-One microfluidic design to integrate vascularized tumor spheroid into high-throughput platform

The development of a scalable and highly reproducible in vitro tumor microenvironment (TME) platform still sheds light on new insights into cancer metastasis mechanisms and anticancer therapeutic strategies. Here, we present an all-in-one injection molded plastic array 3D culture platform (All-in-One-IMPACT) that integrates vascularized tumor spheroids for highly reproducible, high-throughput experimentation. This device allows the formation of self-assembled cell spheroids on a chip by applying the hanging drop method to the cell culture channel. Then, when the hydrogel containing endothelial cells and fibroblasts is injected, the spheroid inside the droplet can be patterned together in three dimensions along the culture channel. In just two steps above, we can build a vascularized TME within a defined area. This process does not require specialized user skill and minimizes error-inducing steps, enabling both reproducibility and high-throughput of the experiment. We have successfully demonstrated the process, from spheroid formation to tumor vascularization, using patient-derived cancer cells (PDCs) as well as various cancer cell lines. Furthermore, we performed combination therapies with Taxol (paclitaxel) and Avastin (bevacizumab), which are used in standard care for metastatic cancer. The All-in-One IMPACT is a powerful tool for establishing various anticancer treatment strategies through the development of a complex TME for use in high-throughput experiments. This article is protected by copyright. All rights reserved.

Abstract 2313: Fenbendazole induces cell cycle arrest in colorectal cancer cells and patient-derived colon cancer organoids

Colorectal cancer is one of leading cause of cancer-related deaths. Therefore, there have been various attempts to cure the cancer by developing new efficient anti-cancer therapy in addition to surgical resection and chemotherapy. In this study, we investigated the effects of fenbendazole, an anti-helminthic drug, both colon cancer cells and patient-derived colon tumor organoids. Notably, we employed 3D tumor organoid models because 2D-cultured cell lines were not able to recapitulate the physiology of solid tumors. We first observed that treatment of fenbendazole to colon cancer cells induced apoptosis within 24 hours, which was extended for a long-term. We revealed that fenbendazole markedly suppressed proliferation rate via cell cycle arrest. Cell cycle progression is elaborately regulated by multiple genes, such as cyclins and cyclin-dependent kinases (CDKs). From a screening of cell cycle-related factors, we found that the protein levels of CDK1 phosphorylated at Tyr15 and cyclin B1 which was known to regulate M phase transition, were drastically downregulated when the tumor cells were exposed to fenbendazole. Next, colorectal tumor-bearing mouse model was established using AOM/DSS. Oral administration of fenbendazole into the mouse not only reduced the number of tumor cells but also lowered tumor grades. Overall, our study suggested a possibility that fenbendazole could be applied for anti-cancer therapy by targeting cell cycle arrest.

Citation Format: Kyung-Sun Kang, Da-Hyun Kim. Fenbendazole induces cell cycle arrest in colorectal cancer cells and patient-derived colon cancer organoids [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2313.

Immunomodulatory Effect of Epidermal Growth Factor Secreted by Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells on Atopic Dermatitis

Background and Objectives

Human mesenchymal stem cells (MSCs) are emerging as a treatment for atopic dermatitis (AD), a chronic inflammatory skin disorder that affects a large number of people across the world. Treatment of AD using human umbilical cord blood-derived MSCs (hUCB-MSCs) has recently been studied. However, the mechanism underlying their effect needs to be studied continuously. Thus, the objective of this study was to investigate the immunomodulatory effect of epidermal growth factor (EGF) secreted by hUCB-MSCs on AD.

Methods and Results

To explore the mechanism involved in the therapeutic effect of MSCs for AD, a secretome array was performed using culture medium of hUCB-MSCs. Among the list of genes common for epithelium development and skin diseases, we focused on the function of EGF. To elucidate the effect of EGF secreted by hUCB-MSCs, EGF was downregulated in hUCB-MSCs using EGF-targeting small interfering RNA. These cells were then co-cultured with keratinocytes, Th2 cells, and mast cells. Depletion of EGF disrupted immunomodulatory effects of hUCB-MSCs on these AD-related inflammatory cells. In a Dermatophagoides farinae-induced AD mouse model, subcutaneous injection of hUCB-MSCs ameliorated gross scoring, histopathologic damage, and mast cell infiltration. It also significantly reduced levels of inflammatory cytokines including interleukin (IL)-4, tumor necrosis factor (TNF)-α, thymus and activation-regulated chemokine (TARC), and IL-22, as well as IgE levels. These therapeutic effects were significantly attenuated at all evaluation points in mice injected with EGF-depleted hUCB-MSCs.

Conclusions

EGF secreted by hUCB-MSCs can improve AD by regulating inflammatory responses of keratinocytes, Th2 cells, and mast cells.

Generation of Cortical Brain Organoid with Vascularization by Assembling with Vascular Spheroid

Background and Objectives

Methods and Results

Conclusions

Combined Mesenchymal Stem Cells and Cartilage Acellular Matrix Injection Therapy for Osteoarthritis in Goats

BACKGROUND

Human umbilical cord blood-derived MSCs (hUCB-MSCs) have been studied in osteoarthritis (OA) and cartilage regeneration. Our previous study demonstrated that hUCB-MSCs combined with cartilage acellular matrix injection (CAM Inj.) represent potential therapeutic agents for structural improvement and anti-inflammatory effects in a rabbit model of OA.

METHODS

Based on a previous study, this study has evaluated the safety and efficacy of hUCB-MSCs combined with CAM Inj. in an anterior cruciate ligament transection (ACLT) with medial meniscectomy (MMx) in a goat model. In this study, 27 goats were divided into 5 groups: normal (n = 3), OA (n = 6), OA + CAM Inj. (n = 6), OA + hUCB-MSCs (n = 6), and OA + hUCB-MSCs + CAM Inj. (n = 6). Lameness and radiographic parameters were assessed 6 months after administration, and macroscopic and histological evaluations of the goat articular cartilage were performed 6 months after intervention.

RESULTS

The results showed significant improvement in lameness score only in the OA + hUCB-MSCs group at 5 months after treatment (*p < 0.05), whereas the K&L score showed significant improvement only in the OA + hUCB-MSCs + CAM Inj. group 6 months after intervention (*p < 0.05). In addition, the gross findings showed significance in OA + CAM Inj. and OA + hUCB-MSCs + CAM Inj. groups 6 months after treatment (*p < 0.05 and **p < 0.01).

CONCLUSION

In conclusion, treatment with a combination of hUCB-MSCs and CAM Inj. reduced OA symptoms and induced effective cartilage tissue repair in a goat model. We suggest the combination of hUCB-MSCs and CAM Inj. as an alternative therapy for OA.

Accumulation of APP-CTF induces mitophagy dysfunction in the iNSCs model of Alzheimer's disease

Mitochondrial dysfunction is associated with familial Alzheimer’s disease (fAD), and the accumulation of damaged mitochondria has been reported as an initial symptom that further contributes to disease progression. In the amyloidogenic pathway, the amyloid precursor protein (APP) is cleaved by β-secretase to generate a C-terminal fragment, which is then cleaved by γ-secretase to produce amyloid-beta (Aβ). The accumulation of Aβ and its detrimental effect on mitochondrial function are well known, yet the amyloid precursor protein-derived C-terminal fragments (APP-CTFs) contributing to this pathology have rarely been reported. We demonstrated the effects of APP-CTFs-related pathology using induced neural stem cells (iNSCs) from AD patient-derived fibroblasts. APP-CTFs accumulation was demonstrated to mainly occur within mitochondrial domains and to be both a cause and a consequence of mitochondrial dysfunction. APP-CTFs accumulation also resulted in mitophagy failure, as validated by increased LC3-II and p62 and inconsistent PTEN-induced kinase 1 (PINK1)/E3 ubiquitin ligase (Parkin) recruitment to mitochondria and failed fusion of mitochondria and lysosomes. The accumulation of APP-CTFs and the causality of impaired mitophagy function were also verified in AD patient-iNSCs. Furthermore, we confirmed this pathological loop in presenilin knockout iNSCs (PSEN KO-iNSCs) because APP-CTFs accumulation is due to γ-secretase blockage and similarly occurs in presenilin-deficient cells. In the present work, we report that the contribution of APP-CTFs accumulation is associated with mitochondrial dysfunction and mitophagy failure in AD patient-iNSCs as well as PSEN KO-iNSCs.

Vascularization of iNSC spheroid in a 3D spheroid-on-a-chip platform enhances neural maturation

In vitro platforms for studying the human brain have been developed, and brain organoids derived from stem cells have been studied. However, current organoid models lack three-dimensional (3D) vascular networks, limiting organoid proliferation, differentiation, and apoptosis. In this study, we created a 3D model of vascularized spheroid cells using an injection-molded microfluidic chip. We cocultured spheroids derived from induced neural stem cells (iNSCs) with perfusable blood vessels. Gene expression analysis and immunostaining revealed that the vascular network greatly enhanced spheroid differentiation and reduced apoptosis. This platform can be used to further study the functional and structural interactions between blood vessels and neural spheroids, and ultimately to simulate brain development and disease.

Pimecrolimus interferes the therapeutic efficacy of human mesenchymal stem cells in atopic dermatitis by regulating NFAT-COX2 signaling

Background

Human mesenchymal stem cells (hMSCs) therapy has recently been considered a promising treatment for atopic dermatitis (AD) due to their immunomodulation and tissue regeneration ability. In our previous studies, we demonstrated that hMSCs alleviate allergic inflammation in murine AD model by inhibiting the activation of mast cells and B cells. Also our phase I/IIa clinical trial showed clinical efficacy and safety of hMSCs in moderate-to-severe adult AD patients. However, hMSCs therapy against atopic dermatitis have had poor results in clinical field. Therefore, we investigated the reason behind this result. We hypothesized that drug–cell interaction could interfere with the therapeutic efficacy of stem cells, and investigated whether coadministration with pimecrolimus, one of the topical calcineurin inhibitors, could influence the therapeutic potential of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) in AD.

Methods

hUCB-MSCs were subcutaneously injected to AD-induced mice with or without pimecrolimus topical application. To examine whether pimecrolimus influenced the immunomodulatory activity of hUCB-MSCs, hUCB-MSCs were treated with pimecrolimus.

Results

Pimecrolimus disturbed the therapeutic effect of hUCB-MSCs when they were co-administered in murine AD model. Moreover, the inhibitory functions of hUCB-MSCs against type 2 helper T (Th2) cell differentiation and mast cell activation were also deteriorated by pimecrolimus treatment. Interestingly, we found that pimecrolimus decreased the production of PGE₂, one of the most critical immunomodulatory factors in hUCB-MSCs. And we demonstrated that pimecrolimus downregulated COX2-PGE₂ axis by inhibiting nuclear translocation of NFAT3.

Conclusions

Coadministration of pimecrolimus with hMSCs could interfere with the therapeutic efficacy of hMSCs in atopic dermatitis, and this is the first study that figured out the interaction of hMSCs with other drugs in cell therapy of atopic dermatitis. Therefore, this study might give rise to improvement of the clinical application of hMSCs therapy and facilitate the widespread application of hMSCs in clinical field.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02547-8.

Enhanced genome editing efficiency of CRISPR PLUS: Cas9 chimeric fusion proteins

Efforts to improve CRISPR-Cas9 genome editing systems for lower off-target effects are mostly at the cost of its robust on-target efficiency. To enhance both accuracy and efficiency, we created chimeric SpyCas9 proteins fused with the 5′-to-3′ exonuclease Recombination J (RecJ) or with GFP and demonstrated that transfection of the pre-assembled ribonucleoprotein of the two chimeric proteins into human or plant cells resulted in greater targeted mutagenesis efficiency up to 600% without noticeable increase in off-target effects. Improved activity of the two fusion proteins should enable editing of the previously hard-to-edit genes and thus readily obtaining the cells with designer traits.

Therapeutic Effects of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Combined with Cartilage Acellular Matrix Mediated Via Bone Morphogenic Protein 6 in a Rabbit Model of Articular Cruciate Ligament Transection

Osteoarthritis (OA) is a general joint disease. Cartilage damage is associated with a decrease in the density of chondrocytes. Mesenchymal stem cells (MSCs) differentiate into adipocytes, osteocytes and chondrocytes, and are an excellent source of cell therapy. Cartilage-derived extracellular matrix (ECM) promotes chondrogenesis of MSCs. However, the role of MSCs stimulated by ECM is not well known in OA. The purpose of this study is to determine the role of specific factors generated by the application of ECM and umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) in managing OA symptoms. Cartilage acellular matrix (CAM), which is a cartilage-derived ECM, was used to promote the chondrogenesis of UCB-MSCs. Induced MSCs were analyzed using chondrogenic markers (aggrecan, collagen type 2, and SOX9) and bone morphogenic protein 6 (BMP6). BMP6 is known to be involved in early chondrogenesis of MSCs. As a result, treatment with CAM significantly increased the expression of chondrogenic markers and BMP6 in UCB-MSCs. Treatment with recombinant human BMP6 also dramatically increased the levels of chondrogenic markers in UCB-MSCs. In addition, UCB-MSCs and CAM were used to evaluate OA symptom improvement in a rabbit articular cruciate ligament transection (ACLT) model. Application of UCB-MSCs and CAM enhanced not only the structure and synthesis of proteoglycan and collagen type 2 but also anti-inflammatory effects in both rabbit joint and synovial fluid. Moreover, the detection of human cells and involvement of BMP6 were confirmed in rabbit cartilage tissues. This study indicates that therapeutic potential of UCB-MSCs with CAM is mediated via BMP6 in OA.

Human Leukocyte Antigen Class I Pseudo-Homozygous Mesenchymal Stem Cells Derived from Human Induced Pluripotent Stem Cells

Mesenchymal stem cells (MSC) are an important type of cell that are highly recognized for their safety and efficacy as a cell therapy agent. In order to obtain MSC, primary tissues (adipose tissue, bone marrow, and umbilical cord blood) must be used; however, these tissues, especially umbilical cord blood, are difficult to obtain due to various reasons, such as the low birth rate trend. In addition, to maximize the safety and efficacy of MSC as allogenic cell therapeutic agents, it is desirable to minimize the possibility of an immune rejection reaction after in vivo transplantation. This study tried to establish a novel method for producing induced pluripotent stem cells (iPSC)-derived MSC in which the human leukocyte antigen (HLA)-class I gene is knocked out. To do so, dermal fibroblast originated iPSC generation using Yamanaka 4-factor, HLA class I gene edited iPSC generation using CRISPR/Cas9, and differentiation from iPSC to MSC using MSC culture medium was utilized. Through this, HLA-A, B, and C pseudo-homozygous iPSC-derived MSC (KO iMSC) were produced by monoallelically knocking out the polymorphic HLA-A, B, and C genes, which are the major causes of immune rejection during allogenic cell transplantation. Produced KO iMSC possesses multipotency and it was safe in vivo to be able to be differentiated to cartilage. In addition, it was not attacked by natural killer cells unlike HLA class I null cells. In conclusion, KO iMSC that do not induce immune rejection during allogenic cell transplantation can be produced. In the future, KO iMSC can be successfully utilized as allogenic cell therapeutic agents for many recipients through HLA screening.

Graphene Quantum Dots from Carbonized Coffee Bean Wastes for Biomedical Applications

Recent studies concerning graphene quantum dots (GQDs) focus extensively on their application in biomedicine, exploiting their modifiable optical properties and ability to complex with various molecules via π–π or covalent interactions. Among these nascent findings, the potential therapeutic efficacy of GQDs was reported against Parkinson’s disease, which has to date remained incurable. Herein, we present an environmentally friendly approach for synthesizing GQDs through a waste-to-treasure method, specifically from coffee waste to nanodrug. Consistent with the previous findings with carbon fiber-derived GQDs, the inhibitory effects of coffee bean-derived GQDs demonstrated similar effectiveness against abnormal α-synuclein fibrillation and the protection of neurons from relevant subcellular damages. The fact that a GQDs-based nanodrug can be prepared from a non-reusable yet edible source illustrates a potential approach to convert such waste materials into novel therapeutic agents with minimal psychological rejection by patients.

Polycystin-1 Enhances Stemmness Potential of Umbilical Cord Blood-Derived Mesenchymal Stem Cells

Polycystic Kidney Disease (PKD) is a disorder that affects the kidneys and other organs, and its major forms are encoded by polycystin-1 (PC1) and polycystin-2 (PC2), as PKD1 and PKD2. It is located sandwiched inside and outside cell membranes and interacts with other cells. This protein is most active in kidney cells before birth, and PC1 and PC2 work together to help regulate cell proliferation, cell migration, and interactions with other cells. The molecular relationship and the function between PKD1 and cancer is well known, such as increased or decreased cell proliferation and promoting or suppressing cell migration depending on the cancer cell type specifically. However, its function in stem cells has not been revealed. Therefore, in this study, we investigated the biological function of PC1 and umbilical cord blood-derived mesenchymal stem cell (UCB-MSC). Furthermore, we assessed how it affects cell migration, proliferation, and the viability of cells when expressed in the PKD1 gene. In addition, we confirmed in an ex vivo artificial tooth model generated by the three-dimension printing technique that the ability to differentiate into osteocytes improved according to the expression level of the stemness markers when PKD1 was expressed. This study is the first report to examine the biological function of PKD1 in UCB-MSC. This gene may be capable of enhancing differentiation ability and maintaining long-term stemness for the therapeutic use of stem cells.

Graphene Quantum Dots Alleviate Impaired Functions in Niemann-Pick Disease Type C in Vivo

While the neuropathological characteristics of Niemann-Pick disease type C (NPC) result in a fatal diagnosis, the development of clinically available therapeutic agent remains a challenge. Here we propose graphene quantum dots (GQDs) as a potential candidate for the impaired functions in NPC in vivo. In addition to the previous findings that GQDs exhibit negligible long-term toxicity and are capable of penetrating the blood-brain barrier, GQD treatment reduces the aggregation of cholesterol in the lysosome through expressed physical interactions. GQDs also promote autophagy and restore defective autophagic flux, which, in turn, decreases the atypical accumulation of autophagic vacuoles. More importantly, the injection of GQDs inhibits the loss of Purkinje cells in the cerebellum while also demonstrating reduced activation of microglia. The ability of GQDs to alleviate impaired functions in NPC proves the promise and potential of the use of GQDs toward resolving NPC and other related disorders.

Modeling of Hypoxic Brain Injury through 3D Human Neural Organoids

Brain organoids have emerged as a novel model system for neural development, neurodegenerative diseases, and human-based drug screening. However, the heterogeneous nature and immature neuronal development of brain organoids generated from pluripotent stem cells pose challenges. Moreover, there are no previous reports of a three-dimensional (3D) hypoxic brain injury model generated from neural stem cells. Here, we generated self-organized 3D human neural organoids from adult dermal fibroblast-derived neural stem cells. Radial glial cells in these human neural organoids exhibited characteristics of the human cerebral cortex trend, including an inner (ventricular zone) and an outer layer (early and late cortical plate zones). These data suggest that neural organoids reflect the distinctive radial organization of the human cerebral cortex and allow for the study of neuronal proliferation and maturation. To utilize this 3D model, we subjected our neural organoids to hypoxic injury. We investigated neuronal damage and regeneration after hypoxic injury and reoxygenation. Interestingly, after hypoxic injury, reoxygenation restored neuronal cell proliferation but not neuronal maturation. This study suggests that human neural organoids generated from neural stem cells provide new opportunities for the development of drug screening platforms and personalized modeling of neurodegenerative diseases, including hypoxic brain injury.

Combinatorial Strategies for Long-term Control of HIV Infection

AIDS is a disease caused by a chronic infection of HIV. Recently, long-term control of HIV infection has been demonstrated through the bone marrow transplantation of hematopoietic stem cells (HSC), in which the C-C chemokine receptor type 5 (CCR5) gene is mutated innately. However, it is very difficult to obtain CCR5 mutant HSC that match human leukocyte antigen between donor and recipient. To solve this problem, this review will summarize and discuss various reports related to the generation of patient-specific CCR5 geneedited HSC. The fusion of current gene editing (zinc-finger nuclease, transcription activator-like effector nuclease, and clustered regulatory interspaced short palindromic repeats) and cellular reprogramming technology (somatic cell nuclear transfer, induced pluripotent stem cells technology, and direct phenotypic conversion) enables the generation of patient-specific CCR5 edited HSC. These cells can be useful as valuable therapeutic agents for long-term control of HIV-infected patients in the future.

Human iNSC-derived brain organoid model of lysosomal storage disorder in Niemann-Pick disease type C

Recent studies on developing three-dimensional (3D) brain organoids from stem cells have allowed the generation of in vitro models of neural disease and have enabled the screening of drugs because these organoids mimic the complexity of neural tissue. Niemann-Pick disease, type C (NPC) is a neurodegenerative lysosomal storage disorder caused by mutations in the NPC1 or NPC2. The pathological features underlying NPC are characterized by the abnormal accumulation of cholesterol in acidic compartments, including late endosomes and lysosomes. Due to the inaccessibility of brain tissues from human NPC patients, we developed NPC brain organoids with induced neural stem cells from NPC patient-derived fibroblasts. NPC organoids exhibit significantly reduced size and proliferative ability, which are accompanied by accumulation of cholesterol, impairment in neuronal differentiation, and autophagic flux and dysfunction of lysosomes; therefore, NPC organoids can recapitulate the main phenotypes of NPC patients. Furthermore, these pathological phenotypes observed in NPC organoids were reversed by treatment with valproic acid and HPBCD, which are known to be an effective treatment for several neurodegenerative diseases. Our data present patient-specific phenotypes in 3D organoid-based models of NPC and highlight the application of this model to drug screening in vitro.

Extracellular Vesicles from SOD3-Transduced Stem Cells Exhibit Improved Immunomodulatory Abilities in the Murine Dermatitis Model

The immunoregulatory abilities of mesenchymal stem cells (MSCs) have been investigated in various autoimmune and allergic diseases. However, the therapeutic benefits observed in preclinical settings have not been reproducible in clinical trials. This discrepancy is due to insufficient efficacy of MSCs in harsh microenvironments, as well as batch-dependent variability in potency. Therefore, to achieve more beneficial and uniform outcomes, novel strategies are required to potentiate the therapeutic effect of MSCs. One of simple strategies to augment cellular function is genetic manipulation. Several studies showed that transduction of antioxidant enzyme into cells can increase anti-inflammatory effects. Therefore, we evaluated the immunoregulatory abilities of MSCs introduced with extracellular superoxide dismutase 3 (SOD3) in the present study. SOD3-overexpressed MSCs (SOD3-MSCs) reduced the symptoms of murine model of atopic dermatitis (AD)-like inflammation, as well as the differentiation and activation of various immune cells involved in AD progression. Interestingly, extracellular vesicles (EVs) isolated from SOD3-MSCs delivered SOD3 protein. EVs carrying SOD3 also exerted improved therapeutic efficacy, as observed in their parent cells. These results suggest that MSCs transduced with SOD3, an antioxidant enzyme, as well as EVs isolated from modified cells, might be developed as a promising cell-based therapeutics for inflammatory disorders.

Effects of conditioned media from human umbilical cord blood-derived mesenchymal stem cells in the skin immune response

Atopic dermatitis (AD) is an inflammatory skin disease in which type 2 allergic inflammation plays a critical role. In this study, the anti-inflammatory effect of conditioned media from human umbilical cord blood-derived mesenchymal stem cells (USC-CM) was investigated in order to apply it as an effective treatment with a low risk of side effects that can overcome the limitations of AD treatment which is currently in use. We found that USC-CM has various growth factors and cytokines associated with anti-inflammatory effect. RT-PCR and ELISA analysis showed that USC-CM inhibited the levels of type 2 cytokine and chemokine Thymus and activation-regulated chemokine (TARC), TNF-α and IL-6 in TNF-α/IFN-γ-stimulated HaCaT cells. In addition, USC-CM inhibited IL-4 and IL-13 levels in Th2 cells. Therefore, the results of our study demonstrated that USC-CM has anti-inflammatory effect in TNF-α/IFN-γ-stimulated HaCaT cells which associated with the inhibition of the immunoglobulin (IgE) secretion by activating B cell line. Our In vivo results showed that when the USC-CM was applied to lesions of patients with the mild AD for 4 weeks, the skin barrier was strengthened by increasing the level of Corneometer and decreasing the value of transepidermal water loss (TEWL). In conclusion, the results suggest that USC-CM may have therapeutic effect for AD as cosmetics and drug materials.

Development of highly functional bioengineered human liver with perfusable vasculature

Liver tissue engineering offers a promising strategy for liver failure patients. Since transplantation rejection resulting in vessel thrombosis is regarded as a major hurdle, vascular reconstruction is one of indispensable requirements of whole organ engineering. Here we demonstrated a novel strategy for reconstruction of a vascularized bioengineered human liver (VBHL) using decellularized liver scaffolds in an efficient manner. First we achieved fully functional endothelial coverage of scaffolds by adopting the anti-CD31 aptamer as a potent coating agent for re-endothelialization. Through an ex vivo human blood perfusion that recapitulates the blood coagulation response in humans, we demonstrated significantly reduced platelet aggregation in anti-CD31 aptamer coated scaffolds. We then produced VBHL constructs using liver parenchymal cells and nonparenchymal cells, properly organized into liver-like structures with an aligned vasculature. Interestingly, VBHL constructs displayed prominently enhanced long-term liver-specific functions that are affected by vascular functionality. The VBHL constructs formed perfusable vessel networks in vivo as evidenced by the direct vascular connection between the VBHL constructs and the renal circulation. Furthermore, heterotopic transplantation of VBHL constructs supported liver functions in a rat model of liver fibrosis. Overall, we proposed a new strategy to generate transplantable bioengineered livers characterized by highly functional vascular reconstruction.

Functional enhancement strategies for immunomodulation of mesenchymal stem cells and their therapeutic application

Mesenchymal stem cells (MSCs) have recently been considered a promising alternative treatment for diverse immune disorders due to their unique biomedical potentials including the immunomodulatory property and ability to promote tissue regeneration. However, despite many years of pre-clinical studies in the research field, results from clinical trials using these cells have been diverse and conflicting. This discrepancy is caused by several factors such as poor engraftment, low survival rate, and donor-dependent variation of the cells. Enhancement of consistency and efficacy of MSCs remains a challenge to overcome the current obstacles to MSC-based therapy and subsequently achieve an improved therapeutic outcome. In this review, we investigated function enhancement strategies by categorizing as preconditioning, genetic manipulation, usage of supportive materials, and co-administration with currently used drugs. Preconditioning prior to MSC application makes up a large proportion of improvement strategies and preconditioning reagents include bioactive substances (cytokines, growth factors, and innate immune receptor agonists), hypoxia, and modification in culture method. With the piled results from previous studies using each method, disease- or patient-specific therapy has become more important than ever. On the other hand, genetic manipulation targeting therapeutic-associated factors or co-administration of biocompatible materials has also arisen as other therapeutic strategies. Thus, we summarized several specialized tactics by analyzing up-to-date results in the field and proposed some promising enhancement methods to improve the clinical outcomes for MSC therapy.

TGF-β secreted by human umbilical cord blood-derived mesenchymal stem cells ameliorates atopic dermatitis by inhibiting secretion of TNF-α and IgE

Human mesenchymal stem cells (MSCs) are promising therapeutics for autoimmune diseases due to their immunomodulatory effects. In particular, human umbilical cord blood-derived MSCs (hUCB-MSCs) have a prominent therapeutic effect on atopic dermatitis (AD). However, the underlying mechanism is unclear. This study investigated the role of transforming growth factor-beta (TGF-β) in the therapeutic effect of hUCB-MSCs on AD. Small interfering RNA (siRNA)-mediated depletion of TGF-β disrupted the therapeutic effect of hUCB-MSCs in a mouse model of AD by attenuating the beneficial changes in histopathology, mast cell infiltration, tumor necrosis factor-alpha (TNF-α) expression, and the serum IgE level. To confirm that hUCB-MSCs regulate secretion of TNF-α, we investigated whether they inhibit TNF-α secretion by activated LAD2 cells. Coculture with hUCB-MSCs significantly inhibited secretion of TNF-α by LAD2 cells. However, this effect was abolished by siRNA-mediated depletion of TGF-β in hUCB-MSCs. TNF-α expression in activated LAD2 cells was regulated by the extracellular signal-related kinase signaling pathway and was suppressed by TGF-β secreted from hUCB-MSCs. In addition, TGF-β secreted by hUCB-MSCs inhibited maturation of B cells. Taken together, our findings suggest that TGF-β plays a key role in the therapeutic effect of hUCB-MSCs on AD by regulating TNF-α in mast cells and maturation of B cells.

Graphene quantum dots as anti-inflammatory therapy for colitis

While graphene and its derivatives have been suggested as a potential nanomedicine in several biomimetic models, their specific roles in immunological disorders still remain elusive. Graphene quantum dots (GQDs) may be suitable for treating intestinal bowel diseases (IBDs) because of their low toxicity in vivo and ease of clearance. Here, GQDs are intraperitoneally injected to dextran sulfate sodium (DSS)-induced chronic and acute colitis model, and its efficacy has been confirmed. In particular, GQDs effectively prevent tissue degeneration and ameliorate intestinal inflammation by inhibiting T_H1/T_H17 polarization. Moreover, GQDs switch the polarization of macrophages from classically activated M1 to M2 and enhance intestinal infiltration of regulatory T cells (T_regs). Therefore, GQDs effectively attenuate excessive inflammation by regulating immune cells, indicating that they can be used as promising alternative therapeutic agents for the treatment of autoimmune disorders, including IBDs.

Repeated intramuscular transplantations of hUCB-MSCs improves motor function and survival in the SOD1 G93A mice through activation of AMPK

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is characterized by loss of motor neurons and degeneration of neuromuscular junctions. To improve disease progression, previous studies have suggested many options that have shown beneficial effects in diseases, especially stem cell therapy. In this study, we used repeated intramuscular transplantation of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) and observed positive effects on muscle atrophy and oxidative stress. In an in vivo study, motor function, body weight and survival rate were assessed, and skeletal muscle tissues were analyzed by western blotting and immunohistochemistry. After intramuscular transplantation, the hUCB-MSCs survived within the skeletal muscle for at least 1 week. Transplantation ameliorated muscle atrophy and the rate of neuromuscular degeneration in skeletal muscle through reductions in intracellular ROS levels. Both expression of skeletal muscle atrophy markers, muscle atrophy F-box (MAFbx)/atrogin1 and muscle RING finger 1 (MuRF1), were also reduced; however, the reductions were not significant. Moreover, transplantation of hUCB-MSCs improved protein synthesis and inhibited the iNOS/NO signaling pathway through AMPK activation. Our results suggest that repeated intramuscular transplantation of hUCB-MSCs can be a practical option for stem cell therapy for ALS.

Interferon-γ-mediated secretion of tryptophanyl-tRNA synthetases has a role in protection of human umbilical cord blood-derived mesenchymal stem cells against experimental colitis

Mesenchymal stem cells (MSCs) are multipotent adult stem cells that present immunosuppressive effects in experimental and clinical trials targeting various rare diseases including inflammatory bowel disease (IBD). In addition, recent studies have reported tryptophanyl-tRNA synthetase (WRS) possesses uncanonical roles such as angiostatic and anti-inflammatory effects. However, little is known about the function of WRS in MSC-based therapy. In this study, we investigated if a novel factor, WRS, secreted from MSCs has a role in amelioration of IBD symptoms and determined a specific mechanism underlying MSC therapy. Experimental colitis was induced by administration of 3% DSS solution to 8-week-old mice and human umbilical cord blood-derived MSCs (hUCB-MSCs) were injected intraperitoneally. Secretion of WRS from hUCB-MSCs and direct effect of WRS on isolated CD4⁺ T cells was determined via in vitro experiments and hUCB-MSCs showed significant therapeutic rescue against experimental colitis. Importantly, WRS level in serum of colitis induced mice decreased and recovered by administration of MSCs. Through in vitro examination, WRS expression of hUCB-MSCs increased when cells were treated with interferon-γ (IFN-γ). WRS was evaluated and revealed to have a role in inhibiting activated T cells by inducing apoptosis. In summary, IFN-γ-mediated secretion of WRS from MSCs has a role in suppressive effect on excessive inflammation and disease progression of IBD and brings new highlights in the immunomodulatory potency of hUCB-MSCs.

Preconditioning with interleukin-1 beta and interferon-gamma enhances the efficacy of human umbilical cord blood-derived mesenchymal stem cells-based therapy via enhancing prostaglandin E2 secretion and indoleamine 2,3-dioxygenase activity in dextran sulfate sodium-induced colitis

Preconditioning with inflammatory cytokines has improved mesenchymal stem cells characteristics, including differentiation and immunomodulating functions. In this study, we developed a preconditioning combination strategy using interleukin-1beta (IL-1β) and interferon-gamma (IFN-γ) to enhance the immuneregulatory ability of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs). Our results showed that hUCB-MSCs preconditioned with IL-1β and IFN-γ (primed hUCB-MSCs) created a statistically significant decrease in peripheral blood mononuclear cell proliferation, indicating that their immunosuppressive ability was increased. The secretion of PGE2, cyclooxygenase 2 mRNA expression, and indoleamine 2,3-dioxygenase (IDO) mRNA expression in primed hUCB-MSCs was significantly higher than those in the untreated hUCB-MSCs or the IL-1β or IFN-γ only treated hUCB-MSCs. When inhibitors of IDO and PGE2 were treated, peripheral blood mononuclear cell proliferation, which is inhibited by primed hUCB-MSCs, was recovered. We found that Th1 T cell differentiation was also inhibited by PGE2 and IDO in the primed hUCB-MSCs, and Tregs differentiation was increased by PGE2 and IDO in the primed hUCB-MSCs. Furthermore, the primed hUCB-MSCs as well as supernatants increase CD4⁺ T cells migration. We demonstrated the therapeutic effects of primed hUCB-MSCs in dextran sulfate sodium-induced colitis model. In conclusion, we have demonstrated that primed hUCB-MSCs simultaneously enhance PGE2 and IDO and greatly improve the immunoregulatory capacity of MSCs, and we have developed an optimal condition for pretreatment of MSCs for the treatment of immune diseases. Our results raise the possibility that the combination of PGE2 and IDO could be therapeutic mediators for controlling immunosuppression of MSCs.

Disease-specific primed human adult stem cells effectively ameliorate experimental atopic dermatitis in mice

Although human mesenchymal stem cells (hMSCs) hold considerable promise as an alternative therapeutic reagent for allergic disorders including atopic dermatitis (AD), the strategy for enhancing hMSC-based therapy remains challenging. We sought to investigate whether preconditioning with mast cell (MC) granules could enhance the therapeutic efficiency of human umbilical cord blood-derived MSCs (hUCB-MSCs) against AD.

Methods: AD was experimentally induced in NC/Nga mice by repeated applications of 4% sodium dodecyl sulfate (SDS) and dermatophagoides farinae (Df) extract, and preconditioned hUCB-MSCs were subcutaneously injected. The therapeutic effect was determined by gross examination and additional ex vivo experiments performed using blood and skin samples to determine the resolution of allergic inflammation. To explore the underlying mechanisms, several co-culture assays with primary isolated immune cells and wound closure assays were conducted.

Results: Pretreatment of MC granules enhanced the therapeutic effects of hUCB-MSCs by attenuating the symptoms of AD in an experimental animal model. MC granule-primed cells suppressed the activation of major disease-inducing cells, MCs and B lymphocytes more efficiently than naïve cells both in vitro and in vivo. Histamine-mediated upregulation of the COX-2 signaling pathway was shown to play a crucial role in suppression of the allergic immune response by MC-pretreated hUCB-MSCs. Moreover, MC pretreatment improved the wound healing ability of hUCB-MSCs.

Conclusions: Our findings indicate that pre-exposure to MC granules improved the therapeutic effect of hUCB-MSCs on experimental AD by resolving the allergic immune reaction and accelerating the tissue regeneration process more efficiently than naïve cells, suggesting a potential enhancement strategy for stem cell-based therapy.

Characterization of silver nanoparticle-modified decellularized rat esophagus for esophageal tissue engineering: Structural properties and biocompatibility

Decellularized esophageal matrices are ideal scaffolds for esophageal tissue engineering. Unfortunately, in order to improve transplantation possibilities, they require modification to reduce their degradation rate and immunogenicity. To date, no modifying agent has been approved to overcome these limitations. The objective of this study was to evaluate the ability of silver nanoparticles (AgNPs) to improve the structural stability and biocompatibility of decellularized rat esophagi. AgNPs have the advantage over currently used agents in that they bind with collagen fibers in a highly ordered manner, via non-covalent binding mechanisms forming multiple binding sites, while other agents provide only two-point connections between collagen molecules. Rat esophagi were decellularized, loaded with 5 μg/mL of AgNPs (100 nm), and then treated with an immobilization-complex buffer composed of ethyl carbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS). Then, they were evaluated in terms of ultra-structural morphology, water uptake, in vitro resistance to enzymatic and thermal degradation, indentation strength, in vitro anti-calcification, cytocompatibility with rat bone marrow derived stromal cells (rat-BMSCs), angiogenic properties, and in vivo biocompatibility, and compared to scaffolds modified using glutaraldehyde and EDC/NHS complex buffer alone. AgNP-modified scaffolds showed an improved ultrastructure, good water uptake, and considerable resistance against in vitro degradation and indentation, and a high resistance against in vitro calcification. Moreover, they were cytocompatible for allogeneic rat-BMSCs. Additionally, AgNPs did not alter the angiogenic properties of the modified scaffolds and decreased host immune responses after their subcutaneous implantation. The structural properties and biocompatibility of decellularized esophageal matrices could be improved by conjugation with AgNPs.

TGF-beta in the UCB-MSCs inhibit TNF-alpha in human mast cells and atopic dermatitis

It is well known that umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) have been effective therapy in autoimmune inflammatory disease such as atopic dermatitis (AD), rheumatoid arthritis (RA) and psoriasis. Especially, UCB-MSC has a prominent therapeutic effect on AD. However, there is not much research on the mechanism of alleviation of AD by UCB-MSCs. In this study, we investigated the mechanism of AD therapy by UCB-MSCs, using human mast cells as the major pathogenic cells in AD. LAD2 cells were stimulated with IL- 33(30ng/ml) and Ionomycin (1uM) under IgE-XL condition and they secreted a significant amount of TNF-a. TNFa was significantly inhibited by co-culture with UCB-MSCs. UCB-MSCs secreted TGF-beta and PGE2, which play a crucial role in immune regulation. TNF-a of LAD2 was increased when co-cultured with UCB-MSCs after TGF-b siRNA transfection. Nevertheless, inhibition of PGE2 using indomethacin, NS398 and celecoxib did not restore secretion of TNF-a. At the protein level, we examined the ERK, JNK and AKT signaling pathways involved in TNF-α, and only the ERK signaling pathway was associated with TNF-α inhibition. Finally, we found that TNFa is regulated by TGFb induced by UCB-MSC in a DF-induced mouse model. Taken together, our findings suggest that TGF-b may play an important role in regulating mast cells in AD rather than PGE2 in UCB-MSCs.

Human umbilical cord blood plasma alleviates age-related olfactory dysfunction by attenuating peripheral TNF-α expression

Social requirements are needed for living in an aging society and individual longevity. Among them, improved health and medical cares, appropriate for an aging society are strongly demanded. Human cord blood-derived plasma (hUCP) has recently emerged for its unique anti-aging effects. In this study, we investigated brain rejuvenation, particularly olfactory function, that could be achieved by a systemic administration of young blood and its underlying mechanisms. Older than 24-month-old mice were used as an aged group and administered with intravenous injection of hUCP repetitively, eight times. Anti-aging effect of hUCP on olfactory function was evaluated by buried food finding test. To investigate the mode of action of hUCP, brain, serum and spleen of mice were collected for further ex vivo analyses. Systemic injection of hUCP improved aging-associated olfactory deficits, reducing time for finding food. In the brain, although an infiltration of activated microglia and its expression of cathepsin S remarkably decreased, significant changes of proinflammatory factors were not detected. Conversely, peripheral immune balance distinctly switched from predominance of Type 1 helper T (Th1) cells to alternative regulatory T cells (Tregs). These findings indicate that systemic administration of hUCP attenuates age-related neuroinflammation and subsequent olfactory dysfunction by modulating peripheral immune balance toward Treg cells, suggesting another therapeutic function and mechanism of hUCP administration.

Micro and ultrastructural changes monitoring during decellularization for the generation of a biocompatible liver

Decellularization of a whole organ is an attractive process that has been used to create 3D scaffolds structurally and micro-architecturally similar to the native one. Currently used decellularization protocols exhibit disrupted extracellular matrix (ECM) structure and denatured ECM proteins. Therefore, maintaining a balance between ECM preservation and cellular removal is a major challenge. The aim of this study was to optimize a multistep Triton X-100 based protocol (either using Triton X-100/ammonium hydroxide mixture alone or after its modification with DNase, sodium dodecyl sulfate or trypsin) that could achieve maximum decellularization with minimal liver ECM destruction suitable for subsequent organ implantation without immune rejection. Based on our findings, Triton X-100 multistep protocol was insufficient for whole liver decellularization and needed to be modified with other detergents. Among all Triton X-100 modified protocols, a Triton X-100/DNase-based one was considered the most suitable. It maintains a gradual but sufficient removal of cells to generate decellularized biocompatible liver scaffolds without any significant alteration to ECM micro- and ultra-structure.

Forkhead box O3 promotes cell proliferation and inhibits myotube differentiation in chicken myoblast cells

1. In the poultry industry, growth performance is important due to its effects on economic value. Much effort has been put forth to achieve introgression of specific genes and DNA markers related to muscle proliferation and differentiation in selective breeding approaches. 2. This study investigated the biological functions of the gene Forkhead box O3 (FOXO3) during myogenic differentiation in chicken myoblast cells. FOXO3 was downregulated in primary chicken myoblast (pCM) cells by the piggyBac transposon-mediated microRNA (miRNA) knock-down (KD) system. 3. The pCM cells that were stably integrated into the FOXO3 KD expression vector showed significant downregulation of FOXO3 protein and mRNA levels. Expression levels of paired box protein Pax7 (Pax7) and target genes such as CCAAT/enhancer binding protein beta and serum response element decreased in FOXO3 KD pCM cells. In addition, in the undifferentiated myoblast stage, there were no significant differences in cell morphology; however, proliferation rate in FOXO3 KD pCM cells was significantly lower during d 4 and 5 of in vitro culture. By contrast, when myotube differentiation was induced, FOXO3 KD pCM cells exhibited rapid initiation of myotube formation, higher expression of myogenin and desmin as myogenic indicators and a further differentiated phenotype than observed in regular pCM cells. 4. These results demonstrated that FOXO3 promotes cell proliferation and inhibits myotube differentiation in chicken myoblast cells. Therefore, the regulation of FOXO3 could be applied to improve muscle differentiation in commercial poultry.

Enhanced therapeutic effects of human mesenchymal stem cells transduced with superoxide dismutase 3 in a murine atopic dermatitis-like skin inflammation model

BACKGROUND

The use of mesenchymal stem cells (MSCs) has been proposed to treat various autoimmune diseases. However, effective strategies for treating atopic dermatitis (AD) are still lacking, and the mechanisms underlying stem cell therapy remain largely unknown. In this study, we sought to explore potential clinical application of superoxide dismutase 3-transduced MSCs (SOD3-MSCs) to experimental AD-like skin inflammation in in vitro and in vivo and its underlying anti-inflammatory mechanisms.

METHODS

SOD3-MSCs were administered subcutaneously to mice with AD, and associated symptoms and biologic changes were evaluated. Human keratinocytes, mast cells, and murine T helper (Th) 2 cells were cocultured in vitro with SOD3-MSCs to investigate potential therapeutic effects of SOD3-MSCs.

RESULTS

In mice with AD, SOD3-MSCs ameliorated AD pathology and enhanced the efficacy of MSC therapy by controlling activated immune cells, by reducing expression levels of proinflammatory mediators in the skin, and by inhibiting the histamine H₄ receptor (H4R)-mediated inflammatory cascade and activation of Janus kinase signal transducer and activator of transcription pathways. Similarly, coculture of SOD3-MSCs with mast cells, keratinocytes, and Th2 cells effectively dampened H4R-dependent persistent inflammatory responses by multiple mechanisms. Moreover, we also showed that SOD3 interacts with H4R and IL-4 receptor α. The functional significance of this interaction could be a markedly reduced inflammatory response in keratinocytes and overall AD pathogenesis, representing a novel mechanism for SOD3's anti-inflammatory effects.

CONCLUSION

SOD3-MSCs can be potentially used as an effective and clinically relevant therapy for AD and other autoimmune disorders.

Conditioned media from human umbilical cord blood-derived mesenchymal stem cells stimulate rejuvenation function in human skin

Developing treatments that inhibit skin aging is an important research project. Rejuvenation, which focuses on prevention of skin aging, is one of the major issues. Recent studies suggested that mesenchymal stem cells (MSCs) secrete many cytokines, which are important in wound healing. In this study, we investigated the effect of human umbilical cord blood-derived mesenchymal stem cells conditioned media (USC-CM) in cutaneous wound healing and collagen synthesis. We found that USC-CM has many useful growth factors associated with skin rejuvenation, such as Epithelial Growth Factor (EGF), basic Fibroblast Growth Factor (bFGF), Platelet Derived Growth Factor (PDGF), Hepatocyte Growth Factor (HGF), Collagen type 1, and especially, one of the rejuvenation factors, the growth differentiation factor-11 (GDF-11). Our in vitro results showed that USC-CM stimulate growth and extracellular matrix (ECM) production of Human Dermal Fibroblasts (HDFs) compared to those of other MSCs conditioned media (CM) from different origins. Moreover, we evaluated the roles of GDF-11. The results showed that GDF-11 accelerates growth, migration and ECM production of HDFs. Our In vivo results showed that topical treatment of USC-CM showed anti-wrinkle effect and significantly increased dermal density in women. In conclusion, USC-CM has various useful growth factors including GDF-11 that can stimulate skin rejuvenation by increasing growth and ECM production of HDFs.

•

USC-CM has various growth factors associated with skin rejuvenation including GDF-11 that strongly promoted HDFs migration, collagen synthesis in vitro compared with HDF- and AD-MSC-CM.

•

USC-CM increased dermal density and decreased skin wrinkle in human.

Microglial involvement in the development of olfactory dysfunction

Olfactory impairment is the most common clinical manifestation among the elderly, and its prevalence increases sharply with age. Notably, growing evidence has shown that olfactory dysfunction is the first sign of neurodegeneration, indicating the importance of olfactory assessment as an early marker in the diagnosis of neurological disorders. In this review, we describe the nature of olfactory dysfunction and the advantage of using animal models in olfaction study, and we include a brief introduction to olfactory behavior tests widely used in this field. The contribution of microglia in the neurodegenerative processes including olfactory impairment is then discussed to provide a comprehensive description of the physiopathological role of interactions between neurons and microglia within the olfactory system.