30†A new step on amniotic membrane extract eye drops (AMEED) development for the treatment of severe ocular surface pathologies.

INTRODUCTION: Our tissue establishment developed a protocol for processing amniotic membranes as extracts to be re-hydrated and administered topically as eye drops, becoming a new approach to treat severe ocular surface pathologies. From 2015 to 2017 the safety and efficacy of the amniotic membrane extract eye drops (AMEED) were assessed in patients with severe ocular surface pathologies through clinical follow-up of ocular surface symptoms before and after regular application of the extract.Between 2018 and 2019 a study of 36 patients (50 eyes) treated with topical AMEED was conducted comparing 2 groups of patients: Dry Eye Disease (DED) and Wound Healing Delay (WHD) showing global similar symptomatic improvement in both groups (DED 88.9% vs WHD 100%; p= 0.486) with the WHD group especially consisting in general relief (78%) and DED group reporting more pain improvement (44%) (p=0.011). Regarding patients with autologous serum as previous treatment, no statistical differences were found in subjective or objective improvement. An overall success was achieved in 94.4% of the cases and no adverse events were found. From January 2020 to November 2021 a growth stage has been observed including more patients while optimizing and scaling the process from donation to clinical use. MATERIALS AND METHODS: We record data of placenta donation and preparation of AMEED vials from 1/1/2020 to 30/11/2021 and its clinical use including the indications for treatment, number of requesting ophthalmologists and number of patients. RESULTS: In the study period a total of 378 placentas were processed to obtain AMEDD (61 in 2020 and 317 in 2021). The number of suitable vials obtained were: 1845 and 6464 respectively and 1946 vials are stored in quarantine pending release for clinical use.A total of 9365 vials were sent for treatment of ocular surface pathologies to 31 hospitals (98% in Catalonia) and 69 requesting ophthalmologists.The total number of patients treated was 204 and the indications for treatment were 82% DED and 18% WHD. CONCLUSION: After the new product development and introduction stages, a significant increase in the use of AMEED in Catalan hospitals was observed in 2020-2021. Follow-up data of these patients should be assessed to demonstrate its efficacy and achieve the maturity stage.

38†Lyophilized amniotic membrane for pterygium surgery: long-term outcomes.

PURPOSE: To investigate the tolerability, security and long-term efficacy of lyophilized amniotic membrane (LAM) as an alternative to cryopreserved amniotic membrane in pterygium surgery. MATERIAL AND METHODS: Prospective case series of patients with primary nasal pterygium who undergone pterygium surgery and LAM implant either with sutures or glue. Postoperative follow-up was until month 24. Clinical and cosmetic outcomes, quality of life (as ocular comfort), and complications were evaluated. RESULTS: LAM was stiff and easy to manipulate as well as no tearing occurred during surgery or suturing. 4 patients (3 males) had pterygium surgery and LAM implant two with sutures and the other two with glue. Ocular comfort was checked and similar among those patients with LAM glued or sutured. After 24 months, there were no issues about tolerability or adverse events. Lower cosmetic outcomes (recurrence) were stated in 3 patients. CONCLUSION: Our study showed that LAM could be an effective alternative to cryopreserved amniotic membrane for graft after pterygium excision surgery. Its main advantage, storage at room temperature, can make it of immediate availability. Further studies comparing clinical outcomes of pterygium surgery with cryopreserved amniotic membrane versus LAM would confirm the benefits of the last.

4†New strategies in the barcelona eye bank to minimize the impact of the COVID-19 pandemic.

Since the start of the pandemic, the tissue donation in Catalonia (Spain) has decreased drastically. At the beginning of the lockdown (from March to May 2020) there was a drop of around 70% in donation of corneas and of approximately 90% in donation of placentas. Despite the fast updating of standard operating procedures, we had big difficulties in different points. For instance, in the availability of the transplant coordinator for the donor detection and evaluation, in obtaining the necessary PPE (personal protective equipment), or in the resources available in the quality control laboratories for screening. This, added to the collapse that hospitals suffered due to the large number of patients hospitalized each day, made donation levels slowly rebound.In order to provide solutions to all patients, we tried to adapt quickly to these emerging changes.In the case of corneas, we found a scenario that we had never had before. Although the cornea transplant plummeted at the beginning of the confinement (decreased by 60% compared to 2019), we run out of corneas -even for emergency situations- at the end of March.This situation led us to develop a new type of therapeutic solution in our Eye Bank. The cryopreserved cornea for tectonic purposes is a tissue that is kept frozen at -196°C and can be preserved for up to 5 years. Therefore, it is a tissue that allows us to respond to possible emergencies in subsequent similar situations.Regarding amniotic membrane for ocular care indications, the strategy was completely different. For this kind of tissue, we carried out an adaptation of our processing with two different purposes. On the one hand, to make sure that we could inactivate the SARS-CoV-2 virus, if it was there. On the other hand, to increase the donation of placentas. For this, changes in the transport medium and in the antibiotic cocktail were performed. In addition, an irradiation step was added to the final product.Little by little, it seems that the donations of corneas and placentas have been recovering. However, it is necessary to think about future contingency strategies in case a stop in donation is repeated.

Amniotic membrane extract eye drops for ocular surface diseases: use and clinical outcome in real-world practice.

PURPOSE: To study the indications and clinical outcomes, in a real-word setting, of amniotic membrane extract eye drops (AMEED) use for ocular surface disease (OSD). METHODS: A retrospective study of patients treated with topical AMEED between January 2018 and January 2020 was conducted. Patients were classified in two groups according to specific OSD-dry eye disease (DED) and wound healing delay (WHD) groups. Demographics, comorbidities, treatment duration and clinical outcomes were analysed. RESULTS: A total of 50 eyes of 36 patients with or without previous treatments were included. Patients in the DED group presented more systemic comorbidities (83 vs 22%; p < 0.001) and spent more mean time under AMEED treatment (10 vs 7.2 months average) than the WHD group (p = 0.0104). In four patients, long-term treatment (more than 24 months) was reported. Global similar symptomatic improvement was reported for both groups (DED 88.9% vs WHD 100%; p = 0.486), with the WHD group especially consisting in general relief (78%) and the DED group reporting more pain improvement (44%) (p = 0.011). Regarding patients with autologous serum as a previous treatment, no statistical differences were found in subjective or objective improvement. An overall success was achieved in 94.4% of the cases and no adverse events were found. CONCLUSION: AMEED administration is a promising mean to treat OSD such as dry eye, persistent epithelial defect and corneal ulcers. Although AMEED may be effective in the treatment of severe DED and persistent epithelial defect or corneal ulcers, conclusions are limited owing to the absence of controlled clinical trials.

First-in-human PeriCord cardiac bioimplant: Scalability and GMP manufacturing of an allogeneic engineered tissue graft.

BACKGROUND: Small cardiac tissue engineering constructs show promise for limiting post-infarct sequelae in animal models. This study sought to scale-up a 2-cm2 preclinical construct into a human-size advanced therapy medicinal product (ATMP; PeriCord), and to test it in a first-in-human implantation. METHODS: The PeriCord is a clinical-size (12-16 cm2) decellularised pericardial matrix colonised with human viable Wharton's jelly-derived mesenchymal stromal cells (WJ-MSCs). WJ-MSCs expanded following good manufacturing practices (GMP) met safety and quality standards regarding the number of cumulative population doublings, genomic stability, and sterility. Human decellularised pericardial scaffolds were tested for DNA content, matrix stiffness, pore size, and absence of microbiological growth. FINDINGS: PeriCord implantation was surgically performed on a large non-revascularisable scar in the inferior wall of a 63-year-old male patient. Coronary artery bypass grafting was concomitantly performed in the non-infarcted area. At implantation, the 16-cm2 pericardial scaffold contained 12·5 × 106 viable WJ-MSCs (85·4% cell viability; <0·51 endotoxin units (EU)/mL). Intraoperative PeriCord delivery was expeditious, and secured with surgical glue. The post-operative course showed non-adverse reaction to the PeriCord, without requiring host immunosuppression. The three-month clinical follow-up was uneventful, and three-month cardiac magnetic resonance imaging showed ~9% reduction in scar mass in the treated area. INTERPRETATION: This preliminary report describes the development of a scalable clinical-size allogeneic PeriCord cardiac bioimplant, and its first-in-human implantation. FUNDING: La Marató de TV3 Foundation, Government of Catalonia, Catalan Society of Cardiology, "La Caixa" Banking Foundation, Spanish Ministry of Science, Innovation and Universities, Institute of Health Carlos III, and the European Regional Development Fund.

Cryopreserved and frozen hyaline cartilage imaged by environmental scanning electron microscope. An experimental and prospective study.

OBJECTIVE: To obtain images of the articular surface of osteochondral grafts (fresh, frozen, and cryopreserved in RPMI) using an environmental scanning electron microscope (ESEM). To evaluate and compare the main morphological aspects of the chondral surface of the fresh, frozen, and cryopreserved grafts as visualized via ESEM. METHODS: The study was based on osteochondral fragments from the internal condyle of the knee joint of New Zealand rabbits, corresponding to the chondral surface from fresh, frozen, and cryopreserved samples. One hundred ESEM images were obtained from each group and then classified according to a validated system. The kappa index and the corresponding concordance index were calculated, and the groups were compared by Pearson's chi-squared test (p < 0.05). RESULTS: The articular surface of cryopreserved osteochondral grafts had fewer even surfaces and filled lacunae and a higher number of empty lacunae as compared to fresh samples; these differences correspond to images of cell membrane lesions that lead to destruction of the chondrocyte. Frozen grafts showed more hillocky and knobby surfaces than did fresh grafts; they also had a greater number of empty chondrocyte lacunae. CONCLUSION: ESEM is useful for obtaining images of the surface of osteochondral grafts. When compared to fresh samples, cryopreservation in RPMI medium produces changes in the surface of hyaline cartilage, but to a lesser extent than those produced by freezing.

Effects of cryopreservation on the immunogenicity of porcine arterial allografts in early stages of transplant vasculopathy.

BACKGROUND: The number of revascularization procedures including coronary and lower extremity bypass, have increased greatly in the last decade. It suggests a growing need for vascular grafts. Cryopreserved allografts could represent a viable alternative but their immunologic reactivity remains controversial. METHODS: 71 pigs (40 recipients and 31 donors) were used. Two femoral grafts per recipient animal were implanted for 3, 7, and 30 days. Types of grafts: fresh autograft as a control graft (n=19), fresh allograft (n=31) and cryopreserved allograft (n=30). Histological and immunohistochemical studies were performed. RESULTS: Fresh allografts compared to autografts showed intimal inflammatory infiltration at 3 days (328 vs. 0 macrophages/mm2; P<0.05) and 7 days (962 vs. 139 T lymphocytes/mm2; P<0.05) post-transplantation. At 30 days, there was a loss of endothelial cells, presence of luminal thrombus and aneurismal lesions (total area=15.8 vs. 8.4 mm2; P<0.05). Cryopreservation did not reduce these lesions nor modify endothelial nitric oxide synthase (eNOS) expression nor modify the number of animals that developed anti-SLA antibodies. Moreover, at 7 days, cryopreserved allografts compared to fresh allografts showed a higher expression of P-selectin (5 out of 5 vs. 1 out of 5; P<0.05) and, at 30 days, a greater inflammatory reactivity (2692 vs. 1107 T lymphocytes/mm2 in media; P<0.05) with a trend towards a higher presence of multinucleated giant cells than in the fresh ones. CONCLUSIONS: The cryopreservation method used maintained immunogenicity of allografts and increased the inflammatory reactivity found in fresh allografts up to 30 days of vascular transplantation.

Isolated bicuspid pulmonary valve: an unusual finding.

Whilst the pulmonary valve is a tricuspid valve, very few reports exist of bicuspid pulmonary valves, the majority of which are associated with congenital heart disease. Isolated bicuspid valves not associated with congenital abnormalities are even more rare. Herein, the case is described of a 65-year-old man who died from a stroke, and in whom a bicuspid pulmonary valve was found during post-mortem dissection for tissue donation.

Soporte hepático bioartificial en la insuficiencia hepática aguda grave. Primer caso tratado en España / Bioartificial liver support for acute liver failure. First case treated in Spain

FUNDAMENTO: En el último decenio se ha asistido a un aumento creciente en la investigación dirigida a desarrollar sistemas de soporte hepático artificial. Por primera vez se han diseñado sistemas híbridos que incorporan biorreactores que contienen hepatocitos a través de los que circula la sangre o plasma de los enfermos con insuficiencia hepatocelular. Se pretende que estos hepatocitos puedan sustituir, al menos en parte, la función del hígado enfermo y de esta manera mejorar el pronóstico de los pacientes con hepatopatías graves agudas o crónicas. OBSERVACIÓN CLÍNICA: En el presente artículo describimos el primer caso tratado en España en el contexto de un estudio aleatorizado, controlado, multicéntrico e internacional dirigido a investigar la eficacia y seguridad de un sistema de soporte hepático bioartificial basado en hepatocitos porcinos criopreservados en pacientes con insuficiencia hepática aguda grave o disfunción primaria del injerto. RESULTADOS: En esta primera experiencia se completaron dos sesiones de tratamiento antes de que la paciente, afectada de un cuadro de insuficiencia hepática aguda grave, pudiera ser sometida a un trasplante hepático urgente, que se completó con éxito. Tras más de dos años de seguimiento la paciente sigue una vida normal y no ha presentado ningún efecto adverso relacionado con el procedimiento de soporte hepático bioartificial al que se sometió. CONCLUSIÓN: Se empieza a disponer de sistemas de soporte hepático bioartificial aplicables en la práctica clínica, si bien deberá esperarse a que se demuestren su seguridad y eficacia antes de aconsejar su uso generalizado (AU)