Manufacturing Parameters for the Creation of Clinical-Grade Human-Induced Pluripotent Stem Cell Lines From Umbilical Cord Mesenchymal Stromal Cells

Induced pluripotent stem cells (iPSCs) are reprogrammed cells with a remarkable capacity for unlimited expansion and differentiation into various cell types. Companies worldwide are actively engaged in developing clinical-grade iPSC lines to address the needs of regenerative medicine, immunotherapies, and precision medicine. However, ensuring the safety and quality of iPSCs is essential, with adherence to Good Manufacturing Practices (GMP) and ethical considerations being paramount. Perinatal cell and tissue banks, such as umbilical cord (UC) blood and tissue banks, are emerging as ideal sources for generating iPSCs due to their unique characteristics and GMP compliance. These banks provide access to immature cells with limited environmental exposure, known family and medical histories of donors, and readily available resources, thereby reducing the time and cost associated with personalized treatment strategies. This study describes the establishment of the first clinical-grade iPSC lines from umbilical cord mesenchymal stromal cells in Brazil. The process involved rigorous quality control measures, safety assessments, and adherence to regulatory standards, resulting in iPSCs with the necessary characteristics for clinical use, including sterility, genomic integrity, and stability. Importantly, the study contributes to the development of a Current Good Manufacturing Practice-compliant iPSC production pipeline in Brazil, using commercially available, chemically defined, and xeno-free products, along with validation by national outsourced laboratories, thereby facilitating the adoption of this technology within the country. The study emphasizes Brazil's contribution to the progress of translational medicine and the promotion of scientific advancements within the field of regenerative and precision medicine.

CD73 mitigates ZEB1 expression in papillary thyroid carcinoma

BACKGROUND

ZEB1, a core transcription factor involved in epithelial-mesenchymal transition (EMT), is associated with aggressive cancer cell behavior, treatment resistance, and poor prognosis across various tumor types. Similarly, the expression and activity of CD73, an ectonucleotidase implicated in adenosine generation, is an important marker of tumor malignancy. Growing evidence suggests that EMT and the adenosinergic pathway are intricately linked and play a pivotal role in cancer development. Therefore, this study focuses on exploring the correlations between CD73 and ZEB1, considering their impact on tumor progression.

METHODS

We employed CRISPR/Cas9 technology to silence CD73 expression in cell lines derived from papillary thyroid carcinoma. These same cells underwent lentiviral transduction of a reporter of ZEB1 non-coding RNA regulation. We conducted studies on cell migration using scratch assays and analyses of cellular speed and polarity. Additionally, we examined ZEB1 reporter expression through flow cytometry and immunocytochemistry, complemented by Western blot analysis for protein quantification. For further insights, we applied gene signatures representing different EMT states in an RNA-seq expression analysis of papillary thyroid carcinoma samples from The Cancer Genome Atlas.

RESULTS

Silencing CD73 expression led to a reduction in ZEB1 non-coding RNA regulation reporter expression in a papillary thyroid carcinoma-derived cell line. Additionally, it also mitigated ZEB1 protein expression. Moreover, the expression of CD73 and ZEB1 was correlated with alterations in cell morphology characteristics crucial for cell migration, promoting an increase in cell polarity index and cell migration speed. RNA-seq analysis revealed higher expression of NT5E (CD73) in samples with BRAF mutations, accompanied by a prevalence of partial-EMT/hybrid state signature expression.

CONCLUSIONS

Collectively, our findings suggest an association between CD73 expression and/or activity and the post-transcriptional regulation of ZEB1 by non-coding RNA, indicating a reduction in its absence. Further investigations are warranted to elucidate the relationship between CD73 and ZEB1, with the potential for targeting them as therapeutic alternatives for cancer treatment in the near future.

Adenosine metabolism by mesenchymal stromal cells isolated from different human tissues

Mesenchymal stromal cells (MSCs) have unique biological properties and play important functions, which make them attractive tools for cell-based therapies. The basic mechanisms of these cells are not fully understood. However, the adenosinergic pathway contributes to the main effects attributed to MSCs. Adenosine is a highly immunosuppressive molecule and exerts a central role in inflammation by neutralizing the proinflammatory ATP influence. This nucleoside is produced by purinergic signaling, an important physiological pathway for MSCs, which involves proliferation, migration, differentiation, and apoptosis. Therefore, in this study, we analyzed the extracellular AMP hydrolysis and consequent adenosine production, as well as the expression of CD73 and adenosine receptors on the cell surface of MSCs isolated from different human tissues: dermis (D-MSCs), adipose tissue (AD-MSCs), and umbilical cord (UC-MSCs). All cells confirmed their multipotent capacity by adipogenic, osteogenic, and chondrogenic differentiation, as well as the expression of cell surface markers including CD44 + , CD105 + , and CD90 + . All MSCs expressed similar levels of CD73 and CD26 without a statistical difference among the different tissues, whereas ADA expression was lower in AD-MSCs. In addition, A1R and A3R mRNA levels were higher in D-MSCs and AD-MSCs, respectively. Enzymatic assay showed that AD-MSCs have the highest hydrolysis rate of AMP, leading to increased amount of adenosine production. Moreover, despite all MSCs completely hydrolyze extracellular AMP generating adenosine, the pattern of nucleosides metabolism was different. Therefore, although MSCs share certain characteristics as the multilineage potential and immunophenotype, they show different adenosinergic profiles according to tissue origin.

A novel method to pack cryopreserved amniotic membrane for wound dressing - The pathway through validation of a new biological product

Amniotic membrane (AM) has been widely used as a biological dressing for many pathologies and illnesses worldwide, and products derived from this tissue have been commercially available in several countries. In Brazil, regulatory agencies have recently authorized its clinical use as a non-experimental therapy for burns, diabetic and venous stasis ulcers, and intrauterine adhesions. In this study, we present our pathway through validating the first available service in the country of AM cryopreservation, with a protocol for long-term storage in high-efficiency nitrogen cryogenic freezers and a specific way of packing the tissue for optimal clinical handling and efficient storage space utilization while preserving live cells and the tissue's biological properties. Using gauze as support, cryoprotectant dimethyl sulfoxide (DMSO) and product presentation as a multilayer roll exhibited the best cell viability results and maintained the tissue integrity and presence of stem/progenitor cells. Essential proteins involved in tissue regeneration and immune and antimicrobial control were detected from the secretome of cryopreserved tissue similar to fresh tissue. Furthermore, immunogenic markers, such as human leukocyte antigens (HLA-DR), were detected at very low levels in the tissue, confirming their low immunogenicity. Finally, we demonstrate that the tissue can be kept under refrigerated conditions for up to 7 days for further use, maintaining sterility and considerable cell viability. Our cryopreservation and storage protocol kept the AM viable for at least 20 months. In conclusion, this study enabled us to determine a novel efficient protocol for long-term AM preservation for future clinical applications&#xD.

A Systematic Review of the Role of Purinergic Signalling Pathway in the Treatment of COVID-19

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global health concern. Three years since its origin, despite the approval of vaccines and specific treatments against this new coronavirus, there are still high rates of infection, hospitalization, and mortality in some countries. COVID-19 is characterised by a high inflammatory state and coagulation disturbances that may be linked to purinergic signalling molecules such as adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine (ADO), and purinergic receptors (P1 and P2). These nucleotides/nucleosides play important roles in cellular processes, such as immunomodulation, blood clot formation, and vasodilation, which are affected during SARS-CoV-2 infection. Therefore, drugs targeting this purinergic pathway, currently used for other pathologies, are being evaluated in preclinical and clinical trials for COVID-19. In this review, we focus on the potential of these drugs to control the release, degradation, and reuptake of these extracellular nucleotides and nucleosides to treat COVID-19. Drugs targeting the P1 receptors could have therapeutic efficacy due to their capacity to modulate the cytokine storm and the immune response. Those acting in P2X7, which is linked to NLRP3 inflammasome activation, are also valuable candidates as they can reduce the release of pro-inflammatory cytokines. However, according to the available preclinical and clinical data, the most promising medications to be used for COVID-19 treatment are those that modulate platelets behaviour and blood coagulation factors, mainly through the P2Y12 receptor.

Relocating to a new facility: The challenge of a cord blood banking transferral in Brazil

BACKGROUND

Our cord blood banking facility planned and executed a transferral of its entire operation to a new site in the South of Brazil. Transporting LN2 freezers is a complex process in which extensive planning is essential to minimize the risks of damaging products or storage units.

METHODS

To fulfill this objective, we constructed a detailed relocation plan consisting of four phases and risk mitigation measures, collaborated with the representatives of all departments, regulating agencies, and professionals from the transport company, and assembled a validation plan for cryogenic freezers and the viability of cord blood units.

RESULTS

The new facility was prepared in accordance with the project plan, local legislation, quality system program requirements, and accreditation agency guidance. A 12-h operation of moving the cryogenic freezers was conducted successfully, with no loss or damage of client samples or equipment.

CONCLUSION

Through the development and execution of a transferral plan, the engagement of appropriate partners, and compliance with security measures from health and government agencies, a successful transferral of a cord blood banking facility operation in its entirety can be successfully accomplished.

The crossroads of adenosinergic pathway and epithelial-mesenchymal plasticity in cancer

Epithelial-mesenchymal transition (EMT) is a key mechanism related to tumor progression, invasion, metastasis, resistance to therapy and poor prognosis in several types of cancer. However, targeting EMT or partial-EMT, as well as the molecules involved in this process, has remained a challenge. Recently, the CD73 enzyme, which hydrolyzes AMP to produce adenosine (ADO), has been linked to the EMT process. This relationship is not only due to the production of the immunosuppressant ADO but also to its role as a receptor for extracellular matrix proteins, being involved in cell adhesion and migration. This article reviews the crosstalk between the adenosinergic pathway and the EMT program and the impact of this interrelation on cancer development and progression. An in silico analysis of RNAseq datasets showed that several tumor types have a significant correlation between an EMT score and NT5E (CD73) and ENTPD1 (CD39) expressions, with the strongest correlations in prostate adenocarcinoma. Furthermore, it is evident that the cooperation between EMT and adenosinergic pathway in tumor progression is context and tumor-dependent. The increased knowledge about this topic will help broaden the view to explore new treatments and therapies for different types of cancer.

Immortalization of Mesenchymal Stromal Cells by TERT Affects Adenosine Metabolism and Impairs their Immunosuppressive Capacity

Mesenchymal stromal cells (MSCs) are promising candidates for cell-based therapies, mainly due to their unique biological properties such as multipotency, self-renewal and trophic/immunomodulatory effects. However, clinical use has proven complex due to limitations such as high variability of MSCs preparations and high number of cells required for therapies. These challenges could be circumvented with cell immortalization through genetic manipulation, and although many studies show that such approaches are safe, little is known about changes in other biological properties and functions of MSCs. In this study, we evaluated the impact of MSCs immortalization with the TERT gene on the purinergic system, which has emerged as a key modulator in a wide variety of pathophysiological conditions. After cell immortalization, MSCs-TERT displayed similar immunophenotypic profile and differentiation potential to primary MSCs. However, analysis of gene and protein expression exposed important alterations in the purinergic signaling of in vitro cultured MSCs-TERT. Immortalized cells upregulated the CD39/NTPDase1 enzyme and downregulated CD73/NT5E and adenosine deaminase (ADA), which had a direct impact on their nucleotide/nucleoside metabolism profile. Despite these alterations, adenosine did not accumulate in the extracellular space, due to increased uptake. MSCs-TERT cells presented an impaired in vitro immunosuppressive potential, as observed in an assay of co-culture with lymphocytes. Therefore, our data suggest that MSCs-TERT have altered expression of key enzymes of the extracellular nucleotides/nucleoside control, which altered key characteristics of these cells and can potentially change their therapeutic effects in tissue engineering in regenerative medicine.

CD73 as a target to improve temozolomide chemotherapy effect in glioblastoma preclinical model

Glioblastoma is the most devastating primary brain tumor and effective therapies are not available. Treatment is based on surgery followed by radio and chemotherapy with temozolomide (TMZ), but TMZ increases patient survival only by 2 months. CD73, an enzyme responsible for adenosine production, emerges as a target for glioblastoma treatment. Indeed, adenosine causes tumor-promoting actions and CD73 inhibition increases sensitivity to TMZ in vitro. Here, a cationic nanoemulsion to nasal delivery of siRNA CD73 (NE-siRNA CD73) aiming glioblastoma treatment was employed alone or in combination with TMZ. In vitro, two glioblastoma cell lines (C6 and U138MG) with a chemo-resistant profile were used. Treatment alone with NE-siRNA CD73 reduced C6 and U138MG glioma cell viability by 70% and 25%, respectively. On the other hand, when NE-siRNA + TMZ combined treatment was employed, a reduction of 85% and 33% of cell viability was observed. Notably, treatment with NE-siRNA CD73 of glioma-bearing Wistar rats reduced tumor size by 80%, 60% more than the standard chemotherapy with TMZ, but no synergistic or additive effect was observed in vivo. Additionally, NE-siRNA CD73, TMZ or combined therapy decreased adenosine levels in liquor confirming the importance of this nucleoside on in vivo GB growth. Finally, no hemolytic potential was observed. These results suggest that nasal administration of NE-siRNA CD73 exhibits higher antiglioma effect when compared to TMZ. However, no synergistic or additive in vivo was promoted by the therapeutic regimen employed in this study.

Imatinib mesylate affects extracellular ATP catabolism and expression of NTPDases in a chronic myeloid leukemia cell line

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm, characterized by the occurrence of the t(9;22)(q34;q11) translocation. First-line therapy for CML consists of treatment with imatinib mesylate, which selectively inhibits the BCR-ABL protein by competing for its ATP-binding site. Adenine nucleotide signaling is modulated by the ectonucleotidases and this pathway is related to tumorigenic processes. Considering the relationship between ATP and cancer, we aimed to evaluate the influence of imatinib mesylate on the expressions and functions of the NTPDase and ecto-5'-nucleotidase (CD73) enzymes in imatinib-sensitive and -resistant K-562 cell lines. mRNA analysis showed that K-562 cells express all ENTPDs and NT5E. However, when treated with imatinib mesylate for 24 h, the expression of ENTPD1, -2, -3 and -5 increased, leading to a higher nucleotides hydrolysis rate. HPLC analysis identified increased ATP degradation in cells after 24 h of treatment, with consequent ADP and AMP formation, corroborating the increase in gene and protein expression of ectonucleotidases as observed in previous results. On the other hand, we observed that imatinib-resistant K-562 cells presented a decrease in nucleotide hydrolysis and expressions of ENTPD1 and -5. These results suggest an involvement of imatinib in modulating ectonucleotidases in CML that will need further investigation. Since these ectonucleotidases have important catalytic activities in the tumor microenvironment, their modulation in CML cells may represent an important therapeutic approach to regulate levels of extracellular adenine nucleotides.

Abstract B058: CD73 siRNA therapy regulates glioblastoma immune microenvironment

Glioblastoma (GB) is the most common primary brain tumor, characterized by high aggressiveness and poor prognostic. Although all efforts, current therapy is just palliative. Therefore, new biological targets are needed to treat this invasive cancer. In this regard, immune modulation emerges as a possibility for cancer therapeutic. Literature has shown that the purinergic system can regulate peripheral immune cell functions and adenosine (ADO) plays an important role as an immunosuppressive molecule. CD73 enzyme activity is considered the main extracellular ADO source and it is overexpressed in a variety of tumors, including GB. According to CD73 participation in tumor progression, studies from our group have shown that CD73 knockdown impairs in vitro and in vivo GB growth. Here, we determined the potential of CD73siRNA (CD73 small interference RNA) delivery using the nanotechnology strategy to reduce tumor growth and modulate GB immune microenvironment (GME) in a preclinical immunocompetent GB model. For this purpose, an in vivo experiment was performed. C6 glioma cells were cultivated and implanted in the striatum of Wistar rat brains (male, 60 d) by stereotaxic surgery. Following 5 days of GB implant, the treatment with CD73siRNA complexed to nanoemulsion (NE) via nasal route has started and continuous by 15 days (twice a day). Experimental groups were composed as follows: control group (glioma-bearing animals that receive saline via nasal route) and treated group (CD73siRNA-NE; 10 µg/kg). After 20 days of GB implant surgery, animals were euthanized and the GB histopathological characteristics were analyzed by HE staining; apoptosis cell death analysis and GME composition were determined by flow cytometry using annexin V and specific antibodies for macrophage and microglia staining. In the histopathological analysis, tumors presented GB characteristics, as necrosis, edema, and angiogenesis. The treatment decreased tumor volume by 60% and increased the GME apoptotic cell index at 10%. Also, the drug interfered in GME population cells, the microglia CD11b+CD45low cells (from 3.4 ± 1.9 to 0.2 ± 0.1 %) and macrophages CD11b+CD45high cells (from 1.22 ± 0.3 to 0.4 ± 0.1 %) were practically abolished in the GME. Our data suggest that the lower tumoral volume is due to the higher apoptotic rates, indicating immune participation in cancer cell death. Furthermore, the absence of microglia and macrophages tumor-associated may contribute to the decreased tumor volume, proposing an immune system activation ADO modulated over the GB.

Citation Format: Gabriela Spies Lenz, Juliana Hofstätter Azambuja, Roselena Silvestri Schuh, Luana Roberta Michels, Nicolly Espindola Gelsleichter, Liziane Raquel Beckenkamp, Gabriela Goncalves Roliano, Frabricio Figueiró, Juliete N. Scholl, Jean Sévigny, Márcia R Wink, Helder Ferreira Teixeira, Elizandra Braganhol. CD73 siRNA therapy regulates glioblastoma immune microenvironment [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B058. doi:10.1158/1535-7163.TARG-19-B058

Antitumor action of diphenyl diselenide nanocapsules: In vitro assessments and preclinical evidence in an animal model of glioblastoma multiforme

BACKGROUND

Gliomas are the most aggressive malignant tumors of the central nervous system. The diphenyl diselenide [(PhSe)₂] is an organoselenium compound that has multiple pharmacological properties. Previous reports showed that (PhSe)₂ nanoencapsulation potentiates its in vitro antitumoral action and reduces its toxicity.

OBJECTIVE

In this sense, the current study was designed to further evaluate the (PhSe)₂ antitumoral effect by a set of in vitro techniques using a glioma cell line as well as by an animal model of gliobastoma.

METHODS

For the in vitro tests, the cell viability, propidium iodide uptake and nitrite levels of rat glioma C6 cells were determined after incubation with free (PhSe)₂ or (PhSe)₂-loaded nanocapsules (NC). The glioblastoma model was induced by implantation of C6 glioma cells in the right striatum of rats. Following, animals were submitted to a repeated intragastric administration treatment with (PhSe)₂ or NC (PhSe)₂ (1 mg/kg/day for 15 days) to assess the possible antitumor effect.

MAIN FINDINGS

Both compound forms decreased the C6 glioma cells viability without causing any effect in astrocytes cells (healthy control). Importantly, the NC (PhSe)₂ had superior cytotoxic effect than its free form and increased the nitrite content. Independent of the (PhSe)₂ forms, the intragastric treatment reduced brain tumor size and caused neither alteration in the plasma renal and hepatic markers of function nor in the parameters of oxidative balance in brain, liver and kidneys.

PRINCIPAL CONCLUSIONS

The (PhSe)₂ nanoencapsulation improved its cytotoxic effect against C6 glioma cells and both compound forms attenuated the tumor development.

Extracellular Nucleotide Hydrolysis in Dermal and Limbal Mesenchymal Stem Cells: A Source of Adenosine Production

Human Limbal (L-MSCs) and Dermal Mesenchymal Stem Cell (D-MSCs) possess many properties that increase their therapeutic potential in ophthalmology and dermatology. It is known that purinergic signaling plays a role in many aspects of mesenchymal stem cells physiology. They release and respond to purinergic ligands, altering proliferation, migration, differentiation, and apoptosis. Therefore, more information on these processes would be crucial for establishing future clinical applications using their differentiation potential, but without undesirable side effects. This study evaluated and compared the expression of ecto-nucleotidases, the enzymatic activity of degradation of extracellular nucleotides and the metabolism of extracellular ATP in D-MSCs and L-MSCs, isolated from discard tissues of human skin and sclerocorneal rims. The D-MSCs and L-MSCs showed a differentiation potential into osteogenic, adipogenic, and chondrogenic lineages and the expression of markers CD105⁺ , CD44⁺ , CD14^- , CD34^- , CD45^- , as expected. Both cells hydrolyzed low levels of extracellular ATP and high levels of AMP, leading to adenosine accumulation that can regulate inflammation and tissue repair. These cells expressed mRNA for ENTPD1, 2, 3, 5 and 6, and CD73 that corresponded to the observed enzymatic activities. Thus, considering the degradation of ATP and adenosine production, limbal MSCs are very similar to dermal MSCs, indicating that from the aspect of extracellular nucleotide metabolism L-MSCs are very similar to the characterized D-MSCs. J. Cell. Biochem. 118: 2430-2442, 2017. © 2017 Wiley Periodicals, Inc.