Long-term storage in liquid nitrogen does not affect cell viability in cardiac valve allografts

Liquid nitrogen is the most common medium used by tissue banks for the storage of cryopreserved heart valves. This study evaluates the effect of the length of storage on human cryopreserved heart valves. Human tissues (14 aortic and 13 pulmonary) were frozen in a controlled-rate freezer (1 degrees C/min) and stored in the liquid phase of a nitrogen tank for 9.1+/-1.6 years. The preservative solution was medium M199 containing 5% human serum albumin and 10% Me(2)SO. After thawing in a water bath at 42 degrees C, the cryoprotectant was removed. Then, fragments from vascular wall and leaflet were dissected. Explant cultures and histological studies were performed in order to assess cell viabil…

Improving ovarian tissue cryopreservation for oncologic patients: slow freezing versus vitrification, effect of different procedures and devices.

Objective To compare slow freezing (SF) with four vitrification techniques (VT) for cryopreservation of ovarian tissue (OT) and to evaluate the best protocol for human OT in a xenograft model. Design Experimental study. Setting University hospital. Patient(s) Patients undergoing fertility preservation. Animal(s) Ovariectomized nude mice. Intervention(s) Cryopreservation of bovine OT after SF and four VTs (VT1, VT2, VT3, and VT4) by combining two cryoprotectant vitrification solutions (VS1 and VS2) and two devices (metallic grid and ethyl vinyl acetate bag), after which the cryopreservation of human OT by SF and VT1 and xenograft into nude mice. Main Outcome Measure(s) Follicular densities, …

Oocyte vitrification versus ovarian cortex transplantation in fertility preservation for adult women undergoing gonadotoxic treatments: a prospective cohort study

Objective To compare the efficacy of oocyte vitrification (OV) with that of ovarian cortex cryopreservation and transplantation (OCT) in women undergoing gonadotoxic treatments. Design Prospective observational cohort study. Setting Not applicable. Patient(s) Candidates for chemo-/radiotherapy who joined our fertility preservation (FP) program were included in this study between 2005 and 2015. One cohort included 1,024 patients undergoing OV; the other cohort included 800 patients undergoing OCT. Intervention(s) OV using the cryotop device and OCT using a slow freezing protocol. Main Outcome Measure(s) Live-birth rate (LBR) and clinical pregnancy rate (CPR). Result(s) Basal antimullerian ho…

Methodological Approach to Use Fresh and Cryopreserved Vessels as Tools to Analyze Pharmacological Modulation of the Angiogenic Growth

The sprouting of new vessels is greatly influenced by the procedure chosen. We sought to optimize the experimental conditions of the angiogenic growth of fresh and cryopreserved vessels cultured in Matrigel with the aim to use this system to analyze the pharmacological modulation of the process. Segments of second-order branches of rat mesenteric resistance arteries, thoracic aorta of rat or mouse, and cryopreserved rat aorta and human femoral arteries were cultured in Matrigel for 7-21 days in different mediums, as well as in the absence of endothelial or adventitia layer. Quantification of the angiogenic growth was performed by either direct measurement of the mean length of the neovessel…

Cranioplasty with autologous bone flaps cryopreserved with Dimethylsulphoxide : does tissue processing matter

Este artículo se encuentra disponible en la siguiente URL: https://www.sciencedirect.com/science/article/abs/pii/S1878875021001625?via%3Dihub En este artículo de investigación también participan: Dolores Ocete, Lucas Aranda, Ana Melero, Antonio J. Guillot, Nuria Yagüe y Carlos Botella. Este es el pre-print del siguiente artículo: Mirabet, V., García, D., Roca, A., Quiroz, A. R., Antón, J., Rodríguez-Cadarso, M., Ocete, D., Aranda, L., Melero, A., Guillot, A. J., Yagüe, N., Guillén, I. & Botella, C. (2021). Cranioplasty with autologous bone flaps cryopreserved with Dimethylsulphoxide: does tissue processing matter. World Neurosurgery, vol. 149 (may.), pp. e582?e591, que se ha publicado de fo…

AB0069 Conditioned media from adipose-derived mesenchymal stem cells decreases senescence and enhances collagen ii expression in osteoarthritic chondrocytes

Background Adipose-derived mesenchymal stem cells (ASC) might act as a cellular source of soluble factors exerting anti-inflammatory or trophic effects on cells. Osteoarthritis (OA) is characterized by the progressive loss of structure and functionality of articular cartilage. Objectives In the present study we explored the effect of conditioned medium from adipose-derived mesenchymal stem cells (ASC-CM) on the metabolism of OA chondrocytes in primary culture. Methods ADC were isolated from adipose tissue of patients subjected to abdominal lipectomy surgery, by collagenase treatment. Cells were incubated in DMEM/F12 + 15% human serum. Cell phenotype was analysed by flow cytometry with speci…

Paracrine effects of human adipose-derived mesenchymal stem cells in inflammatory stress-induced senescence features of osteoarthritic chondrocytes

Aging and exposure to stress would determine the chondrocyte phenotype in osteoarthritis (OA). In particular, chronic inflammation may contribute to stress-induced senescence of chondrocytes and cartilage degeneration during OA progression. Recent studies have shown that adipose-derived mesenchymal stem cells exert paracrine effects protecting against degenerative changes in chondrocytes. We have investigated whether the conditioned medium (CM) from adipose-derived mesenchymal stem cells may regulate senescence features induced by inflammatory stress in OA chondrocytes. Our results indicate that CM down-regulated senescence markers induced by interleukin-1β including senescence-associated β…

Heme oxygenase-1 mediates protective effects on inflammatory, catabolic and senescence responses induced by interleukin-1β in osteoarthritic osteoblasts

Osteoarthritis (OA) is a chronic degenerative joint disease showing altered bone metabolism. Osteoblasts contribute to the regulation of cartilage metabolism and bone remodeling. We have shown previously that induction of heme oxygenase-1 (HO-1) protects OA cartilage against inflammatory and degradative responses. In this study, we investigated the effects of HO-1 induction on OA osteoblast metabolism. HO-1 was induced with cobalt protoporphyrin IX (CoPP) and by transduction with LV-HO-1. In osteoblasts stimulated with interleukin (IL)-1β, CoPP enhanced mineralization, the expression of a number of markers of osteoblast differentiation such as Runx2, bone morphogenetic protein-2, osteocalci…

Conditioned Media from Adipose-Tissue-Derived Mesenchymal Stem Cells Downregulate Degradative Mediators Induced by Interleukin-1β in Osteoarthritic Chondrocytes

Osteoarthritis (OA) is the most frequent joint disorder and an important cause of disability. Recent studies have shown the potential of adipose-tissue-derived mesenchymal stem cells (AD-MSC) for cartilage repair. We have investigated whether conditioned medium from AD-MSC (CM) may regulate in OA chondrocytes a number of key mediators involved in cartilage degeneration. CM enhanced type II collagen expression in OA chondrocytes while decreasing matrix metalloproteinase (MMP) activity in cell supernatants as well as the levels of MMP-3 and MMP-13 proteins and mRNA in OA chondrocytes stimulated with interleukin- (IL-) 1β. In addition, CM increased IL-10 levels and counteracted the stimulating…

Conditioned media from adipose stem cells down-regulates senescence induced by interleukin-1β in osteoarthritic chondrocytes

Biomaterials coated by dental pulp cells as substrate for neural stem cell differentiation

[EN] This study is focused on the development of an in vitro hybrid system, consisting in a polymeric biomaterial covered by a dental pulp cellular stroma that acts as a scaffold offering a neurotrophic support for the subsequent survival and differentiation of neural stem Cells. In the first place, the behavior of dental pulp stroma on the polymeric biomaterial based on ethyl acrylate and hydroxy ethyl acrylate copolymer was studied. For this purpose, cells from normal human third molars were grown onto 0.5-mm-diameter biomaterial discs. After cell culture, quantification of neurotrophic factors generated by the stromal cells was performed by means of an ELISA assay. In the second place, s…

Twins born after transplantation of ovarian cortical tissue and oocyte vitrification

Objective To present a combination of ovarian tissue and oocyte cryopreservation as an effective strategy for achieving pregnancy in a breast cancer patient. Design Case report. Setting Tertiary care university-affiliated hospital, tissue bank, and infertility clinic. Patient(s) A 36-year-old patient diagnosed with atypical medullar breast cancer and negative for estrogen, P, and HER2 receptors underwent ovarian tissue cryopreservation before receiving chemotherapy and radiotherapy. Intervention(s) Laparoscopic ovarian cortex extraction, ovarian tissue cryopreservation, ovarian tissue thawing and transplantation, controlled ovarian stimulation (COS), oocyte retrieval, vitrification and IVF,…

A Xenogeneic-Free Protocol for Isolation and Expansion of Human Adipose Stem Cells for Clinical Uses

Human adipose stem cells (hASCs) play a crucial role in the fields of regenerative medicine and tissue engineering for different reasons: the abundance of adipose tissue, their easy harvesting, the ability to multipotent differentiation and the fact that they do not trigger allogeneic blood response or secrete cytokines that act as immunosuppressants. The vast majority of protocols use animal origin reagents, with the underlying risk of transmitting infections by non-human pathogens. We have designed a protocol to isolate and maintain the properties of hASCs avoiding xenogeneic reagents. These changes not only preserve hASCs morphology, but also increase cell proliferation and maintain thei…

Heart valve tissue engineering: how far is the bedside from the bench?

Heart disease, including valve pathologies, is the leading cause of death worldwide. Despite the progress made thanks to improving transplantation techniques, a perfect valve substitute has not yet been developed: once a diseased valve is replaced with current technologies, the newly implanted valve still needs to be changed some time in the future. This situation is particularly dramatic in the case of children and young adults, because of the necessity of valve growth during the patient's life. Our review focuses on the current status of heart valve (HV) therapy and the challenges that must be solved in the development of new approaches based on tissue engineering. Scientists and physicia…

Human Dental Pulp Stem Cells Improve Left Ventricular Function, Induce Angiogenesis, and Reduce Infarct Size in Rats with Acute Myocardial Infarction

Abstract Human dental pulp contains precursor cells termed dental pulp stem cells (DPSC) that show self-renewal and multilineage differentiation and also secrete multiple proangiogenic and antiapoptotic factors. To examine whether these cells could have therapeutic potential in the repair of myocardial infarction (MI), DPSC were infected with a retrovirus encoding the green fluorescent protein (GFP) and expanded ex vivo. Seven days after induction of myocardial infarction by coronary artery ligation, 1.5 × 106 GFP-DPSC were injected intramyocardially in nude rats. At 4 weeks, cell-treated animals showed an improvement in cardiac function, observed by percentage changes in anterior wall thic…