Human Umbilical Cord-Derived Mesenchymal Stem Cells in the Treatment of Multiple Sclerosis Patients: Phase I/II Dose-Finding Clinical Study.

Multiple sclerosis (MS) is a chronic neuro-inflammatory disease resulting in disabilities that negatively impact patients' life quality. While current treatment options do not reverse the course of the disease, treatment using mesenchymal stromal/stem cells (MSC) is promising. There has yet to be a consensus on the type and dose of MSC to be used in MS. This work aims to study the safety and efficacy of two treatment protocols of MSCs derived from the umbilical cord (UC-MSCs) and their secretome. The study included two groups of MS patients; Group A received two intrathecal doses of UC-MSCs, and Group B received a single dose. Both groups received UC-MSCs conditioned media 3 months post-treatment. Adverse events in the form of a clinical checklist and extensive laboratory tests were performed. Whole transcriptome analysis was performed on patients' cells at baseline and post-treatment. Results showed that all patients tolerated the cellular therapy without serious adverse events. The general disability scale improved significantly in both groups at 6 months post-treatment. Examining specific aspects of the disease revealed more parameters that improved in Group A compared to Group B patients, including a significant increase in the (CD3+CD4+) expressing lymphocytes at 12 months post-treatment. In addition, better outcomes were noted regarding lesion load, cortical thickness, manual dexterity, and information processing speed. Both protocols impacted the transcriptome of treated participants with genes, transcription factors, and microRNAs (miRNAs) differentially expressed compared to baseline. Inflammation-related and antigen-presenting (HLA-B) genes were downregulated in both groups. In contrast, TNF-alpha, TAP-1, and miR142 were downregulated only in Group A. The data presented indicate that both protocols are safe. Furthermore, it suggests that administering two doses of stem cells can be more beneficial to MS patients. Larger multisite studies should be initiated to further examine similar or higher doses of MSCs.

Fusing Peptide Epitopes for Advanced Multiplex Serological Testing for SARS-CoV-2 Antibody Detection.

The tragic COVID-19 pandemic, which has seen a total of 655 million cases worldwide and a death toll of over 6.6 million seems finally tailing off. Even so, new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to arise, the severity of which cannot be predicted in advance. This is concerning for the maintenance and stability of public health, since immune evasion and increased transmissibility may arise. Therefore, it is crucial to continue monitoring antibody responses to SARS-CoV-2 in the general population. As a complement to polymerase chain reaction tests, multiplex immunoassays are elegant tools that use individual protein or peptide antigens simultaneously to provide a high level of sensitivity and specificity. To further improve these aspects of SARS-CoV-2 antibody detection, as well as accuracy, we have developed an advanced serological peptide-based multiplex assay using antigen-fused peptide epitopes derived from both the spike and the nucleocapsid proteins. The significance of the epitopes selected for antibody detection has been verified by in silico molecular docking simulations between the peptide epitopes and reported SARS-CoV-2 antibodies. Peptides can be more easily and quickly modified and synthesized than full length proteins and can, therefore, be used in a more cost-effective manner. Three different fusion-epitope peptides (FEPs) were synthesized and tested by enzyme-linked immunosorbent assay (ELISA). A total of 145 blood serum samples were used, compromising 110 COVID-19 serum samples from COVID-19 patients and 35 negative control serum samples taken from COVID-19-free individuals before the outbreak. Interestingly, our data demonstrate that the sensitivity, specificity, and accuracy of the results for the FEP antigens are higher than for single peptide epitopes or mixtures of single peptide epitopes. Our FEP concept can be applied to different multiplex immunoassays testing not only for SARS-CoV-2 but also for various other pathogens. A significantly improved peptide-based serological assay may support the development of commercial point-of-care tests, such as lateral-flow-assays.

Fabrication of a three-dimensional bone marrow niche-like acute myeloid Leukemia disease model by an automated and controlled process using a robotic multicellular bioprinting system.

BACKGROUND: Acute myeloid leukemia (AML) is a hematological malignancy that remains a therapeutic challenge due to the high incidence of disease relapse. To better understand resistance mechanisms and identify novel therapies, robust preclinical models mimicking the bone marrow (BM) microenvironment are needed. This study aimed to achieve an automated fabrication process of a three-dimensional (3D) AML disease model that recapitulates the 3D spatial structure of the BM microenvironment and applies to drug screening and investigational studies. METHODS: To build this model, we investigated a unique class of tetramer peptides with an innate ability to self-assemble into stable hydrogel. An automated robotic bioprinting process was established to fabricate a 3D BM (niche-like) multicellular AML disease model comprised of leukemia cells and the BM's stromal and endothelial cellular fractions. In addition, monoculture and dual-culture models were also fabricated. Leukemia cell compatibility, functionalities (in vitro and in vivo), and drug assessment studies using our model were performed. In addition, RNAseq and gene expression analysis using TaqMan arrays were also performed on 3D cultured stromal cells and primary leukemia cells. RESULTS: The selected peptide hydrogel formed a highly porous network of nanofibers with mechanical properties similar to the BM extracellular matrix. The robotic bioprinter and the novel quadruple coaxial nozzle enabled the automated fabrication of a 3D BM niche-like AML disease model with controlled deposition of multiple cell types into the model. This model supported the viability and growth of primary leukemic, endothelial, and stromal cells and recapitulated cell-cell and cell-ECM interactions. In addition, AML cells in our model possessed quiescent characteristics with improved chemoresistance attributes, resembling more the native conditions as indicated by our in vivo results. Moreover, the whole transcriptome data demonstrated the effect of 3D culture on enhancing BM niche cell characteristics. We identified molecular pathways upregulated in AML cells in our 3D model that might contribute to AML drug resistance and disease relapse. CONCLUSIONS: Our results demonstrate the importance of developing 3D biomimicry models that closely recapitulate the in vivo conditions to gain deeper insights into drug resistance mechanisms and novel therapy development. These models can also improve personalized medicine by testing patient-specific treatments.

Flow cytometric characterization of cell surface markers to differentiate between fibroblasts and mesenchymal stem cells of different origin.

Introduction: Identification and purification of mesenchymal stem cells (MSCs) expanded in culture for therapeutic use is crucial for improved yield and optimal results. Fibroblasts are the most common cell type in connective tissue and are commonly found as contaminants of MSC cultures, affecting cell yield and potentially causing tumour formation after cell transplantation. In the current study, we wished to identify cell surface markers that can differentiate MSCs of different origins from fibroblasts. Material and methods: Mesenchymal stem cells were isolated from bone marrow, adipose tissue, Wharton's jelly, and placental tissue, and fibroblasts were isolated from foreskin (as a negative control) in order to examine the differences in the expression of a panel of 14 different cell surface markers using multiplex flow cytometry. Results: Our results indicate that the following markers could be useful in differentiating between fibroblasts and MSCs derived from the following: adipose tissue - CD79a, CD105, CD106, CD146, and CD271; Wharton's jelly - CD14, CD56, and CD105; bone marrow - CD105, CD106, and CD146; and placental tissue - CD14, CD105, and CD146. Furthermore, we found that, contradictory to previous studies, CD26 is not fibroblast specific. Conclusions: The results of our study indicate that cell surface markers may prove to be a useful tool in the discrimination between MSCs of different origins and fibroblasts, and thus may be used to authenticate the identity of the isolated cells.

3D bioprinting of ultrashort self-assembling peptides to engineer scaffolds with different matrix stiffness for chondrogenesis.

62Articular cartilage is a nonvascularized and poorly cellularized tissue with a low self-repair capacity. Therefore, damage to this tissue due to trauma or degenerative joint diseases such as osteoarthritis needs a high-end medical intervention. However, such interventions are costly, have limited healing capacity, and could impair patients' quality of life. In this regard, tissue engineering and three-dimensional (3D) bioprinting hold great potential. However, identifying suitable bioinks that are biocompatible, with the desired mechanical stiffness, and can be used under physiological conditions is still a challenge. In this study, we developed two tetrameric self-assembling ultrashort peptide bioinks that are chemically well-defined and can spontaneously form nanofibrous hydrogels under physiological conditions. The printability of the two ultrashort peptides was demonstrated; different shape constructs were printed with high shape fidelity and stability. Furthermore, the developed ultrashort peptide bioinks gave rise to constructs with different mechanical properties that could be used to guide stem cell differentiation toward specific lineages. Both ultrashort peptide bioinks demonstrated high biocompatibility and supported the chondrogenic differentiation of human mesenchymal stem cells. Additionally, the gene expression analysis of differentiated stem cells with the ultrashort peptide bioinks revealed articular cartilage extracellular matrix formation preference. Based on the different mechanical stiffness of the two ultrashort peptide bioinks, they can be used to fabricate cartilage tissue with different cartilaginous zones, including the articular and calcified cartilage zones, which are essential for engineered tissue integration.

Peptide nanogels as a scaffold for fabricating dermal grafts and 3D vascularized skin models.

Millions of people worldwide suffer from skin injuries, which create significant problems in their lives and are costly to cure. Tissue engineering is a promising approach that aims to fabricate functional organs using biocompatible scaffolds. We designed ultrashort tetrameric peptides with promising properties required for skin tissue engineering. Our work aimed to test the efficacy of these scaffolds for the fabrication of dermal grafts and 3D vascularized skin tissue models. We found that the direct contact of keratinocytes and fibroblasts enhanced the proliferation of the keratinocytes. Moreover, the expression levels of TGF-ß1, b-FGF, IL-6, and IL-1α is correlated with the growth of the fibroblasts and keratinocytes in the co-culture. Furthermore, we successfully produced a 3D vascularized skin co-culture model using these peptide scaffolds. We believe that the described results represent an advancement in the fabrication of skin tissue equivalent, thereby providing the opportunity to rebuild missing, failing, or damaged parts.

Differential Marker Expression between Keratinocyte Stem Cells and Their Progeny Generated from a Single Colony.

The stemness in keratinocyte stem cells (KSCs) is determined by their gene expression patterns. KSCs are crucial in maintaining epidermal homeostasis and wound repair and are widely used candidates for therapeutic applications. Although several studies have reported their positive identifiers, unique biomarkers for KSCs remain elusive. Here, we aim to identify potential candidate stem cell markers. Human epidermal keratinocytes (HEKs) from neonatal foreskin tissues were isolated and cultured. Single-cell clonal analysis identified and characterized three types of cells: KSCs (holoclones), transient amplifying cells (TACs; meroclones), and differentiated cells (DSCs; paraclones). The clonogenic potential of KSCs demonstrated the highest proliferation potential of KSCs, followed by TACs and DSCs, respectively. Whole-transcriptome analysis using microarray technology unraveled the molecular signatures of these cells. These results were validated by quantitative real-time polymerase chain reaction and flow cytometry analysis. A total of 301 signature upregulated and 149 downregulated differentially expressed genes (DEGs) were identified in the KSCs, compared to TACs and DSCs. Furthermore, DEG analyses revealed new sets of genes related to cell proliferation, cell adhesion, surface makers, and regulatory factors. In conclusion, this study provides a useful source of information for the identification of potential SC-specific candidate markers.

An In Vitro Comparison of Anti-Tumoral Potential of Wharton's Jelly and Bone Marrow Mesenchymal Stem Cells Exhibited by Cell Cycle Arrest in Glioma Cells (U87MG).

The therapeutic potential of mesenchymal stem cells (MSCs) for various malignancies is currently under investigation due to their unique properties. However, many discrepancies regarding their anti-tumoral or pro-tumoral properties have raised uncertainty about their application for anti-cancer therapies. To investigate, if the anti-tumoral or pro-tumoral properties are subjective to the type of MSCs under different experimental conditions we set out these experiments. Three treatments namely cell lysates (CL), serum-free conditioned media and FBS conditioned media (FBSCM) from each of Wharton's Jelly MSCs and Bone Marrow-MSCs were applied to evaluate the anti-tumoral or pro-tumoral effect on the glioma cells (U87MG). The functional analysis included; Morphological evaluation, proliferation and migration potential, cell cycle analysis, and apoptosis for glioma cells. The fibroblast cell line was added to investigate the stimulatory or inhibitory effect of treatments on the proliferation of the normal cell. We found that cell lysates induced a generalized inhibitory effect on the proliferation of the glioma cells and the fibroblasts from both types of MSCs. Similarly, both types of conditioned media from two types of MSCs exerted the same inhibitory effect on the proliferation of the glioma cells. However, the effect of two types of conditioned media on the proliferation of fibroblasts was stimulatory from BM-MSCs and variable from WJ-MSCs. Moreover, all three treatments exerted a likewise inhibitory effect on the migration potential of the glioma cells. Furthermore, we found that the cell cycle was arrested significantly at the G1 phase after treating cells with conditioned media which may have led to inhibit the proliferative and migratory abilities of the glioma cells (U87MG). We conclude that cell extracts of MSCs in the form of secretome can induce specific anti-tumoral properties in serum-free conditions for the glioma cells particularly the WJ-MSCs and the effect is mediated by the cell cycle arrest at the G1 phase.

Ultrashort Peptide Bioinks Support Automated Printing of Large-Scale Constructs Assuring Long-Term Survival of Printed Tissue Constructs.

We report about rationally designed ultrashort peptide bioinks, overcoming severe limitations in current bioprinting procedures. Bioprinting is increasingly relevant in tissue engineering, regenerative and personalized medicine due to its ability to fabricate complex tissue scaffolds through an automated deposition process. Printing stable large-scale constructs with high shape fidelity and enabling long-term cell survival are major challenges that most existing bioinks are unable to solve. Additionally, they require chemical or UV-cross-linking for the structure-solidifying process which compromises the encapsulated cells, resulting in restricted structure complexity and low cell viability. Using ultrashort peptide bioinks as ideal bodylike but synthetic material, we demonstrate an instant solidifying cell-embedding printing process via a sophisticated extrusion procedure under true physiological conditions and at cost-effective low bioink concentrations. Our printed large-scale cell constructs and the chondrogenic differentiation of printed mesenchymal stem cells point to the strong potential of the peptide bioinks for automated complex tissue fabrication.

The effect of stem cell therapy and comprehensive physical therapy in motor and non-motor symptoms in patients with multiple sclerosis: A comparative study.

INTRODUCTION: People with multiple sclerosis (PwMS) experience a wide range of disabilities which negatively impact their quality of life (QOL). Several interventions have been used in PwMS such as medication, physical therapy exercises and stem cell therapy to improve their QOL. However, there is a limited evidence on the benefits of combining interventions. The purpose of this study is to explore the effect of combining physical therapy exercises (PTE) and Wharton Jelly mesenchymal stem cell (WJ-MSCs) injections on motor and non-motor symptoms versus each intervention alone in PwMS. METHODS: Sixty PwMS will be allocated to either PTE, WJ-MSCs, or a combined group, followed up for 12 months and examined using a comprehensive battery of measures. Participants in the PTE group will receive 2 sessions per week of a supervised exercise program for 6 months followed by a home exercise program for another 6 months. The WJ-MSCs group will receive 3 WJ-MSCs injections in the first 6 months then they will be encouraged to follow an active life style. The third group will receive both interventions. DISCUSSION: This study will aid in a better understanding of the combined effect of physical therapy and mesenchymal stem cell therapy. The results from this proposed study may reduce disability, improve QOL in PwMS, and consequently, reduce the cost associated with the life-time care of these individuals worldwide. TRIAL REGISTRATION NUMBER: NCT03326505.

An insight into the whole transcriptome profile of four tissue-specific human mesenchymal stem cells.

Aim: Variations in the clinical outcomes using mesenchymal stem cells (MSCs) treatments exist, reflecting different origins and niches. To date, there is no consensus on the best source of MSCs most suitable to treat a specific disease. Methods: Total transcriptome analysis of human MSCs was performed. MSCs were isolated from two adult sources bone marrow, adipose tissue and two perinatal sources umbilical cord and placenta. Results: Each MSCs type possessed a unique expression pattern that reflects an advantage in terms of their potential therapeutic use. Advantages in immune modulation, neurogenesis and other aspects were found. Discussion: This study is a milestone for evidence-based choice of the type of MSCs used in the treatment of diseases.

Platelet lysate promotes re-epithelialization of persistent epithelial defects: a pilot study.

PURPOSE: To study the use of autologous platelet lysate prepared in a standardized method for the healing of persistent corneal epithelial defects (PED). STUDY DESIGN: Clinical and experimental investigation. METHODS: In this prospective pilot study (ClinicalTrials.gov identifier NCT02979912), ten patients with a PED duration of a minimum 14 days were included. Autologous platelet lysate was prepared in a standardized methodology. Repeated freeze-thaw cycles were used to lyse the platelets. Patients were advised to apply the eye drops four times a day and were evaluated at baseline and on days 7, 14, 21, 28. RESULTS: No adverse events were reported due to the use of undiluted autologous platelet lysate. A total of 70% of patients had complete re-epithelialization within 28 days. Of these, 40% healed within 14 days (effective group) and 30% within 28 days (partially effective group). CONCLUSIONS: Undiluted autologous platelet lysate, prepared according to a standardized methodology, is a safe and effective adjunct therapy for the treatment of PED.

Intra-articular injection of expanded autologous bone marrow mesenchymal cells in moderate and severe knee osteoarthritis is safe: a phase I/II study.

BACKGROUND: Knee osteoarthritis (KOA) is a major health problem especially in the aging population. There is a need for safe treatment that restores the cartilage and reduces the symptoms. The use of stem cells is emerging as a possible option for the moderate and severe cases. This study aimed at testing the safety of autologous bone marrow mesenchymal stem cells (BM-MSCs) expanded in vitro when given intra-articularly to patients with stage II and III KOA. As a secondary end point, the study tested the ability of these cells to relieve symptoms and restore the knee cartilage in these patients as judged by normalized knee injury and Osteoarthritis Outcome Score (KOOS) and by magnetic resonance imaging (MRI). METHODS: Thirteen patients with a mean age of 50 years suffering from KOA stages II and III were given two doses of BM-MSCs 1 month apart totaling 61 × 106 ± 0.6 × 106 by intra-articular injection in a phase I prospective clinical trial. Each patient was followed for a minimum of 24 months for any adverse events and for clinical outcome using normalized KOOS. Cartilage thickness was assessed by quantitative MRI T2 at 12 months of follow-up. RESULTS: No severe adverse events were reported up to 24 months follow-up. Normalized KOOS improved significantly. Mean knee cartilage thickness measured by MRI improved significantly. CONCLUSION: BM-MSCs given intra-articularly are safe in knee osteoarthrosis. Despite the limited number of patients in this study, the procedure described significantly improved the KOOS and knee cartilage thickness, indicating that they may enhance the functional outcome as well as the structural component. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02118519.

Mesenchymal stem cells and conditioned media in the treatment of multiple sclerosis patients: Clinical, ophthalmological and radiological assessments of safety and efficacy.

AIMS: This open-label prospective phase I/IIa clinical study used autologous bone marrow-derived mesenchymal stromal cells (BM-MSCs) followed by mesenchymal stromal cells conditioned media (MSC-CM) for the first time to treat multiple sclerosis (MS) patients. The primary goal was to assess the safety and feasibility and the secondary was efficacy. The correlation between the MSC-CM content and treatment outcome was investigated. METHODS: Ten MS patients who failed conventional therapy were enrolled. Adverse events were recorded to assess safety. The Expanded Disability Status Scale (EDSS) was the primary efficacy measurement, the secondary included clinical (25WFT, 9-PHT), cognitive (MMS), ophthalmology (OCT, VEP), and radiological (MRI lesion and volume) tests. The MSCs-CM concentration of 27 inflammatory biomarkers was investigated. RESULTS: The treatment protocol was well tolerated by patients. There was an overall trend of improvement in all the tests, except the lesion volume which increased significantly. A decrease of 4 and 3.5 points on the EDSS was achieved in two patients. We report a correlation between a decreased lesion number at baseline and higher IL-6, IL-8, and VEGF MSC-CM content. CONCLUSION: The used protocol was safe and feasible with possible efficacy. The addition of MSC-CM could be related to the magnitude of EDSS improvement observed.