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Pericardial patches are currently used as reconstructive material in cardiac surgery for surgical treatment of cardiac septal defects. Autologous pericardial patches, either treated with glutaraldehyde or not, can be used as an alternative to synthetic materials or xenograft in congenital septal defects repair. The availability of an allogenic decellularized pericardium could reduce complication during and after surgery and could be a valid alternative. Decellularization of allogenic tissues aims at reducing the immunogenic reaction that might trigger inflammation and tissue calcification over time. The ideal graft for congenital heart disease repair should be biocompatible, mechanically resistant, non-immunogenic, and should have the ability to growth with the patients. The aim of the present study is the evaluation of the efficacy of a new decellularization protocol of homologous pericardium, even after cryopreservation. The technique has proven to be suitable as a tissue bank procedure and highly successful in the removal of cells and nucleic acids content, but also in the preservation of collagen and biomechanical properties of the human pericardium.

Homografts have long been used for right ventricular outflow tract (RVOT) reconstruction. Tissue banks struggle to meet the clinical demand of tissue, with insufficient donor availability and strict recommendations on tissue quality with high proportions of discards. This study analyzes the long-term outcome of patients receiving a homograft with small fenestrations of the cusps or other structural changes, to evaluate if minor impairment of the homograft affects the durability. Homograft characteristics and patient outcome were described. Follow-up was maximum 24 years. Structural changes of the homografts were analyzed in relation to patient outcome, using univariable and multivariable Cox proportional hazard regression. Between 1995 and 2018, 468 patients received 535 homografts in the RVOT in Lund. Median recipient age was 13 years. There were 137 (26.9%) reinterventions. Freedom from reintervention was 75.8% (95% CI 71.3–79.7%) at 10 years and 57.4% (95% CI 50.0–64.0%) at 20 years. Small fenestrations of the cusps, fibrosis of the cusps and minor atheromatosis of the vessel did not show any statistically significant impact on long-term outcome, hazard ratio = 0.46 (95% CI 0.11–1.87, p = 0.276) and hazard ratio = 0.80 (95% CI 0.25–2.56, p = 0.704). Minor structural changes of the homografts seem to be acceptable without affecting the long-term durability.

The use of autologous bone flap for cranioplasty after decompressive craniectomy is a widely used strategy that allows alleviating health expenses. When the patient has recovered from the primary insult, the cranioplasty restores protection and cosmesis, recovering fluid dynamics and improving neurological status. During this time, the bone flap must be stored, but there is a lack of standardization of tissue banking practices for this aim. In this work, we have reviewed the literature on tissue processing and storage practices. Most of the published articles are focused from a strictly clinical and surgical point of view, paying less attention to issues related to tissue manipulation. When bone resorption is avoided and the risk of infection is controlled, the autograft represents the most efficient choice, with the lowest risk of complication. Otherwise, depending on the degree of involvement, the patient may have to undergo new surgery, assuming further risks and higher healthcare costs. Therefore, tissue banks must implement protocols to provide products with the highest possible clinical effectiveness, without compromising safety. With a centralised management of tissue banking practices there may be a more uniform approach, thus facilitating the standardization of procedures and guidelines.

The Quality Management System has been a management technology applied to guarantee the quality of processes and products of a given organization. Thus, ISO 9001:2015 certification assists organizations that want to develop, implement, maintain, and improve a quality management system to enable process improvements and assessments to meet the needs of its customers. This experience report addresses the implementation and certification of the ISO 9001:2015 quality management seal at the Human Tissue Bank of the Ribeirão Preto Clinical Hospital (HCRP) at the University of São Paulo (USP) at Ribeirão Preto Medical School (FMRP)-Brazil. In 2018, the Human Tissue Bank, in partnership with HCRP, received consultancies from PRIMEMODE. The consulting consisted of visits that elucidated the processes to the employees of the Tissue Bank, enabling them to clarify the applicability of all items of the standard. In March 2019, the Tissue Bank received the audit visit and was certified with the ISO 9001:2015 Seal by the Carlos Alberto Vanzolini Foundation. The Tissue Bank aims to provide human tissues for transplantation and research from organ donors. It has a complex physical structure within the required health and legal standards. Also, now it has a quality management seal. The certification guarantees the process organization and the high quality standard of the supplied tissues.

On March 19 World Health Organization declare the pandemic situation by outbreak coronavirus disease 2019 in the world. The pressure on the health care system has been very high in several countries. Spanish National Transplant Organization (ONT) have made many efforts in maintaining transplantation activity. Although the impact of the pandemic on organ activity has been analysed, to date, less data exist regarding the impact on tissue activity. The aim of this study has been the evaluation of the possible impact on the procurement, processing and distribution of tissues during the peak period of the pandemic COVID-19 in Spain. For this study, a multicentre analysis has been made with a survey of the tissue banks in Spain, during the period March 1 to April 30, 2020. Our data suggest that the impact of coronavirus in Spain has affected dramatically tissue donation but with a moderate effect on stored tissues such as bone, valves, vessels or skin. Tissue banks should prepare if future next pandemic waves surges so that tissue provision is guaranteed both in urgent and elective surgeries.

Keratoplasty is one of the irreplaceable treatment options for corneal diseases. Currently, there is no evidence to substantiate that harvested corneal grafts from COVID-19 patients can contain SARS-CoV-2 virus and lead to a systemic infection. Although the risk of transmission through corneal stromal tissue is low, it potentially exists. Lack of clinical data, unclear potential of donor-derived infection and non-established recommendations for transplantation during the COVID-19 pandemic have resulted in a dramatic reduction in the number of keratoplasty and cornea donors at ophthalmology departments and eye banks. To eliminate the risk of infection of recipients and medical personnel, we suggest that the blood samples of all donors should be screened with RT-PCR tests and nasopharyngeal swabs should be taken. In addition, a chest CT scan should be performed if the circulation is maintained. Moreover, the donors' clinical and epidemiological medical history must be screened for typical symptoms and potential contact with SARS-CoV-2 carriers to reduce the risk of transmission. The Guidelines of the Eye Bank Association of America (EBAA), Global Alliance of Eye Bank Associations (GAEBA) and European Association of Tissue Banks provide useful recommendations to eliminate the risk of transmission according to previous experiences based on similar viruses.

In this article we describe the organization of post mortem tissue donation in the Netherlands, the average number of tissue donors procured during the years 2015–2019 and the main challenges we face to improve this number. Licensed by the Dutch Ministry of Health, the Dutch Transplant Foundation (NTS) plays a central role in the organization of tissue donation. The NTS works closely with the Dutch hospitals, two tissue banks and a procurement organization. Potential tissue donors are reported to the NTS 24/7. After consulting the Donor Register and relatives give consent for donation, donors are subject to a thorough medical evaluation. If no medical contraindication is mentioned, the donor is approved for tissue donation. Each year, tissues of an average of 1918 donors (112.1 donors Per Million Population) are procured. After procurement of tissues, donor blood and tissues are tested on virology and quality respectively. Based on the test results and the assessment of potential disease transmission, tissues can either be released for transplantation or discarded. In conclusion, the Netherlands has developed a uniform, nationwide approach for safe and efficient post mortem tissue donation in which the NTS plays a central role. In the past 5 years, tissues from a considerable number of donors are procured. The NTS will continue to work together with their partners, by stimulating donor recognition, registration of the donor will, relatives’ informed consent and by extending donor selection criteria, for an even more efficient way to help patients on the waiting list for a transplantation.

Wound excision and temporary coverage with a biologic dressing can improve survival for patients with large burns. Healthcare systems in low- and middle-income countries (LMICs) rarely have access to allografts, which may contribute to the limited survival of patients with large burns in these settings. Therefore, we aimed to describe the lessons learned from the implementation and maintenance of tissue banks in LMICs to guide system planning and organization. PubMed, MEDLINE, CINAHL, and World Health Organization Catalog were systematically searched with database-specific language to represent a priori terms (eg, skin, allograft, and tissue bank) and all LMICs as defined by the World Bank. Data regarding tissue banking programs were extracted and described in a narrative synthesis. The search returned 3346 records, and 33 reports from 17 countries were analyzed. Commonly reported barriers to ideal or planned implementation included high capital costs and operational costs per graft, insufficient training opportunities, opt-in donation schemes, and sociocultural stigma around donation and transplantation. Many lessons were learned from the implementation and management of tissue banks around the world. The availability of skin allografts can be improved through strategic investments in governance and regulatory structures, international cooperation initiatives, training programs, standardized protocols, and inclusive public awareness campaigns. Furthermore, capacity-building efforts that involve key stakeholders may increase rates of pledges, donations, and transplantations. Some issues were ubiquitously reported and could be addressed by current and future tissue banking programs to ensure allograft availability for patients living in countries of all income levels.

The idea of establishing a human tissue bank in Bangladesh was started in 1985. However, in 2003, with the active cooperation of international atomic energy agency (IAEA) and Bangladesh Atomic Energy Commission, a tissue bank laboratory was upgraded as a unit for tissue banking and research. Due to increasing demand of allograft, this unit was transformed as an independent institute “Institute of Tissue Banking and Biomaterial Research (ITBBR)” in 2016. This is the only human tissue bank in Bangladesh, which processes human bone and amniotic membrane to provide safe and cost-effective allografts for transplantation. Importantly, banking of human cranial bone as autograft has also started at ITBBR. These processed grafts are sterilized using gamma radiation according to the IAEA Code of Practice for the radiation sterilization of tissues allografts. The amount of grafts produced by the ITBBR from 2007 to 2018 were 120,800 cc of bone chips, 45,420 cm2 of amniotic membranes, 277 vials of de-mineralized bone granules (DMB), 95 pieces of massive bones, and 134 pieces of cranial bones. Overall, 112,748 cc of bone chips, 40,339 cm2 of amniotic membranes, 174 vials of DMB, 44 pieces of massive bones, and 64 pieces of cranial bones were transplanted successfully. Nevertheless, to cope up with the modern advanced concepts of cell and tissue banking for therapeutic purpose, ITBBR is working to set up facilities for skin banking, stem cells banking including amniotic and cord blood derived stem cells and scaffold designing. To ensure the quality, safety, ethical and regulatory issues are sustainable in cell and tissue banking practices, ITBBR always works with the Government of Bangladesh for enhancing the national tissue transplantation programme within the contemporary facilities.

Assessment of donor suitability and criteria development for tissue donation evaluation which appropriately addresses the risk factors for disease transmission, especially high risk for Hepatitis B or C, HIV or other transmissible diseases as defined by the Food and Drug Administration, FDA, is a continuing concern for tissue banks. The relationship of drug use, especially IV drugs, has been determined to be associated with an increased possibility of reactive serology (Centers for Disease Control and Prevention (USCDC) in Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention. Hepatitis C questions and answers for health professionals. https://www.cdc.gov/hepatitis/hcv/hcvfaq.htm; Centers for Disease Control and Prevention (USCDC) in infectious diseases, opioids and injection drug use, 2018. https://www.cdc.gov/pwid/opioid-use.html; HIH National Institute on Drug Abuse in Health Consequences of Drug Misuse, 2017. https://www.drugabuse.gov/related-topics/health-consequences-drug-misuse). Therefore, prior drug use determined by medical social history screening frequently results in deferral of a potential donor even when the route of drug administration has not been determined to be intravenous. Because of the association of drug use in numerous cases, which come under Medical Examiner jurisdiction, a possible rule out of a number of otherwise suitable medical examiner cases could occur. This retrospective review of medical examiner cases, tissue bank referrals and tissue donors in a 3-year period examines the relationship, if any, between reactive serology and positive toxicology results. These results would appear to indicate assessment of donor medical social history screening is effective in reducing recovery of high-risk donors.

The aim of this study was to investigate the tolerability, safety and efficacy of new lyophilized amniotic membrane (LAM) presentation for ocular use. A prospective case-series cohort of four patients with primary nasal pterygium which undergone excision and LAM implantation was evaluated for complications and clinical outcomes. Surgical manipulation of LAM was also assessed. LAM was stiff and easy to manipulate as well as no tearing occurred during surgery or suturing. Ocular comfort was checked and similar among those patients with LAM glued or sutured. After 12 months, there were no issues about tolerability or adverse events. Lower cosmetic outcomes (recurrence) were stated in 3 patients. 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.

The Croatian Cardiovascular Tissue Bank (CTB) was established in June 2011. Activities managed by CTB are processing of heart valves and blood vessels, as well as quality control, storage, medical release and distribution of allografts. The aim of this report is to present CTB's vascular tissue activities and retrospectively evaluate the outcomes of their use in the University Hospital Centre Zagreb. Between June 2011 and July 2021, 90 vascular allografts (VAs) from 55 donors after brain death were referred to CTB. Only 54% of VAs met the tissue quality requirements while 46% of tissues were discarded. The most frequent reasons for discard were unacceptable morphology and initial microbiological contamination. Altogether 42 VAs were released for transplantation and 37 of them were used in 27 surgical procedures. The most common indication for surgery was prosthetic graft or stent infection. According to the anatomic position of vascular reconstruction, patients were divided in the aortic and peripheral reconstruction group. A total of 23 patients were treated. In the aortic reconstruction group 58% of patients did not experience any graft-related complications. In the group of patients who underwent peripheral reconstruction significant incidence of reinfection was observed highlighting it as a major graft-related complication. Despite the small patient groups and limited duration of follow-up, presented clinical outcomes provide valuable information on the efficacy of vascular allografts. Additional clinical results collected on a larger patient groups and comparison to other reconstructive treatment options are necessary.

Resumo Objetivo Elaborar um protocolo para a captação, transporte e preservação de tecido osteocondral humano para utilização em banco de tecidos (BT). Métodos Foram analisados fragmentos osteocondrais com dimensão de 2 cm3 de 5 doadores cadáveres com idades entre 15 e 45 anos. As amostras foram armazenadas em meio de preservação celular contendo: albumina humana, Iscove's e vancomicina preservados à temperatura de 4°C. A concentração de proteoglicanos no meio extracelular foi quantificada pelo uso de Safranina-O, enquanto a análise estrutural do tecido foi avaliada através de estudo histológico com lâminas coradas em hematoxilina-eosina. As imagens obtidas foram analisadas segundo os escore histológicos de Mankin e o escore proposto pela OsteoArthritis Research Society International. As amostras foram analisadas com 0, 15, 30 e 45 dias de preservação. Resultados Os fragmentos osteocondrais estudados apresentaram diminuição progressiva na concentração de proteoglicanos com o aumento do tempo de preservação. Após 30 dias de preservação, foram identificadas alterações estruturais com descontinuidade da camada superficial da cartilagem. Segundo os resultados obtidos pelo escore de Mankin, houve diferença com significância estatística entre 15 e 30 dias de preservação do tecido. Conclusão O protocolo descrito definiu o transporte de joelho em bloco imerso em Ringer Lactato em temperatura controlada a 10°C até sua chegada ao BT. Após o processamento, a solução de preservação foi composta por meio de cultura celular sem soro Iscove's suplementado com albumina humana a 10% e vancomicina 100 µg/mL. O tecido foi preservado à temperatura de 4°C até o momento do transplante caracterizando a preservação a fresco.

The use of musculoskeletal allografts has become increasingly popular among surgeons. The purpose of this review is to highlight the procurment and delievery process of fresh osteochondral allografts in the United States. The four distributors of fresh osteochondral allografts in the United States were contacted. Surveys containing quantitative and qualitative sections concerning the procurement and processing of osteochondral allograft tissue were obtained. Our results showed an average of 13 ± 4.24 years of experience with osteochondral allografts. The average donor age ranged from 13.5 ± 3 to 37.5 ± 5 years, with an average age of 27 ± 2.83 years. All donors were between ages 12 and 45 years old. The percentage of screened donors that were accepted for allograft transplant was consistent at 70–75% for 3 out of the 4 tissue banks. The percentage of grafts that expire without implantation ranged from 20% to 29%. Maximum shipping time varied between 24 and 96 hours. Each tissue bank used its own proprietary storage medium. The time from donor death to the harvest of allograft tissue was < 24 hours. The most commonly requested osteochondral allograft tissue for all banks was the medial femoral condyle. The market share of fresh allografts is as follows: Joint Restoration Foundation (JRF) 59.9%, Muskuloskeletal Transplant Foundation (MTF) 15.3%, LifeNet Health (LN) 14.5%, and Regeneration Technology Incorporated (RTI) 10.2%, with approximately 4700 fresh allografts distributed in 2018. This compiled data from the four tissue banks that supply fresh osteochondral allograft in the United States provides important background information for patients and orthopaedic surgeons.

Vascularized composite allotransplantation is the ultimate reconstructive tool when no other means of reconstruction are available. Despite its immense potential, the applicability of vascularized composite allotransplantation is hampered by high rejection rates and the requirement for high doses of immunosuppressive drugs that are associated with severe adverse effects and death. Because this is a non-life-saving procedure, widespread use of vascularized composite allotransplantation demands methods that will allow the reduction or elimination of immunosuppressive therapy. Efficient methods for the cryopreservation of biological cells and tissues have been sought for decades. The primary challenge in the preservation of viable tissue in a frozen state is the formation of intracellular and extracellular ice crystals during both freezing and thawing, which cause irreversible damage to the tissue. Recent proof-of-concept transplantations of a complete cryopreserved and thawed hindlimb in a rat model have demonstrated the potential of such methods. In the current review, the authors discuss how limb cryopreservation can attenuate or eliminate allograft rejection by either enabling better human leukocyte antigen matching or by adaptation of clinical tolerance protocols such as mixed chimerism induction. Also, the authors discuss the possible advantages of cryopreservation in autologous tissue salvage and cryopreservation following trauma. Clinical-grade cryopreservation may revolutionize the field of reconstruction, organ banking, and complex traumatic limb injury management.

INTRODUCTION: Even today, the search for the ideal cardiac valve continues. With advantages of having superior flow dynamics, avoidance of anticoagulation, and resistance to infection, homograft has been shown to have an edge over conventional prosthetic and bioprosthetic valves. But they suffer from disadvantages of limited availability and durability. Our center operates one of the oldest functioning valve banks in the country. We present our experience with homograft valve banking with antibiotic and cryopreserved homografts spread over a quarter century. METHODS: For donor selection, procurement, sterilization, and preservation, the recommendations of the American Association of Tissue Banks are being followed in accordance with statutory provisions of the Transplantation of Human Organs Act, 1994. RESULTS: During 25-year period (1993–2017), 777 hearts were procured. Age of the donors ranged from 2 to 60 years and hearts were procured within 24 h of death. A total of 1646 homografts (774 pulmonary, 774 aortic, 60 mitral valves, 20 descending thoracic aortae, and 18 monocusps) were harvested. A total of 546 (32%) homografts were rejected for various reasons. Nine hundred sixty-seven (56.7%) homografts were used in different procedures. Of these, 478 were pulmonary homografts, 425 were aortic homografts, 39 mitral homografts, 18 monocusps, and 7 descending thoracic aorta homografts. One hundred fifty-four (16%) homografts were antibiotic preserved and the rest 813 (84%) were cryopreserved. CONCLUSIONS: It is possible to run a homograft valve bank with minimum costs. Though, cryopreservation is more expensive, it provides an opportunity to store the valves for an indefinite period and maintain an uninterrupted supply of homografts.

Symptomatic chondral and osteochondral defects affect a large and growing number of patients. A safe and effective surgical treatment for large articular defects is osteochondral allograft (OCA) transplantation. One of the major causes of failure for OCA transplantation is loss of essential chondrocyte viability during the preservation and storage period. It is also possible that metabolic responses of the OCA when transitioning from storage temperature to body temperature may contribute to mechanisms causing failure. The present study was designed to compare MOPSSM -preserved OCAs to those stored using the current standard of care (SOC) method with respect to metabolic responses when rewarmed for transplantation to and maintenance at body temperature (37°C). It was theorized that grafts stored using the MOPSSM protocol would maintain significantly higher chondrocyte viability and produce significantly lower levels of inflammatory mediators and degradative enzymes, and significantly higher levels of chemokines compared to grafts stored using the SOC protocol. Left over SOC and MOPSSM -stored OCA tissues were collected after surgery, and cartilage explants were cultured for 6 days. Media was analyzed for biomarkers using commercially available assays. Cartilage from SOC grafts released significantly higher levels of PGE2, MMP-1, MMP-2, and MMP-13, and significantly lower levels of IL-8 and Gro-α, compared to cartilage from MOPSSM -stored grafts. Clinical significance: These data suggest that OCAs stored using the MOPSSM protocol have potentially less detrimental initial inflammatory and degradative responses to re-warming for transplantation compared to OCAs stored using the current tissue bank protocols. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1530-1536, 2019.

The aortic and pulmonary allograft heart valves (AHV) are used in the cardiac surgery for replacing the impaired semilunar valves. They are harvested from donor hearts and cryostored in tissue banks. The expiration period was set to 5 years arbitrarily. We hypothesized that their mechanical and structural properties do not deteriorate after this period. A total of 64 human AHV (31 aortic and 33 pulmonary) of different length of cryopreservation (fresh, 0-5, 5-10, over 10 years) were sampled to different tissue strips (artery, leaflet, ventriculo-arterial junction) and tested by tensile test with loading velocity 10 mm/min until tissue rupture. Neighbouring regions of tissue were processed histologically and evaluated for elastin and collagen area fraction. The results were evaluated statistically. In aortic AHV, the physical deformation response of wall samples to stress did not changed significantly neither during the process of cryopreservation nor during the first 10 years of storage. In pulmonary AHV, the ultimate strain dropped after 5 years of cryopreservation indicating that pulmonary artery was significantly less deformable at the time of rupture. On the other hand, the ultimate stress was equal during the first 10 years of cryostorage. The changes in collagen and elastin amount in the tissue samples were not associated with mechanical impairment. Neither elasticity, stiffness and solidity nor morphology of aortic and pulmonary AHV did not change reasonably with cryopreservation and in the first 10 years of cryostorage. This evidence suggests that the expiration period might be extended in the future.

Processed and radiation sterilized allograft tissues that can be banked for use on demand are a precious therapeutic resource for the repair or reconstruction of damaged or injured tissues. Skin dressings or skin substitutes like allograft skin, amniotic membrane and bioengineered skin can be used for the treatment of thermal burns and radiation induced skin injuries. Bone grafts can be employed for repairing fracture defects, filling in destroyed regions of bone, and treatment of spinal and joint injuries. A nuclear scenario would result in a large number of casualties due to the heat, blast and radiation effects of the weapon. Perspective of radiation sterilized biological tissues provided by the tissue banks for management of casualties in a nuclear disaster scenario is presented.

A consensus meeting was held in Toronto on February 9–10, 2020 to discuss ways to improve cornea donation and transplantation access in Canada. The meeting brought together eye and tissue bank representatives, health authority and hospital leadership, transplant ophthalmologists, organ donation organizations, transplant recipients, donor families and several national organizations. Through facilitated discussions in multidisciplinary, gender-balanced, and geographically balanced small groups, participants identified opportunities for improvement in the Canadian cornea donation and transplantation system. Discussion occurred around broad themes of donor tissue demand, supply, access, utilization, interprovincial sharing and cost recovery, interprovincial knowledge sharing and research. This event marked the first time in 10 years in which the Canadian cornea transplantation community came together.

The search for the perfect bone graft material is an important topic in material science and medicine. Despite human bone being the ideal material, due to its composition, morphology, and familiarity with cells, autografts are widely considered demanding and cause additional stress to the patient because of bone harvesting. However, human bone from tissue banks can be used to prepare materials in eligible form for transplantation. Without proteins and fats, the bone becomes a non-immunogenic matrix for human cells to repopulate in the place of implantation. To repair bone losses, the granulate form of the material is easy to apply and forms an interconnected porous structure. A granulate composed of β-tricalcium phosphate, pulverized human bone, and chitosan—a potent biopolymer applied in tissue engineering, regenerative medicine, and biotechnology—has been developed. A commercial encapsulator was used to obtain granulate, using chitosan gelation upon pH increase. The granulate has been proven in vitro to be non-cytotoxic, suitable for MG63 cell growth on its surface, and increasing alkaline phosphatase activity, an important biological marker of bone tissue growth. Moreover, the granulate is suitable for thermal sterilization without losing its form—increasing its convenience for application in surgery for guided bone regeneration in case of minor or non-load bearing voids in bone tissue.

Tissue transplantation is one of the recognized treatment strategies for replacing or repairing tissue damage resulting from disease or trauma. A living donor undergoing a surgical procedure can donate the surgical residues, such as femoral head, or placenta for amniotic membrane. Patients undoing solid organ cardiac transplantation can donate their own hearts removed for heart valve banking. Femoral head donated by patients undergoing primary hip replacement is the most widely and commonly banked tissue from living donors and is used in orthopaedic (spine and joint surgery) and oral/maxilliofacial surgery. Tissue donation to transplantation is a multistep process each of which is crucial to ensure safety and quality of the graft. There are many advantages of obtaining tissues from a living donor from tissue banking perspective. From donor selection perspective, the potential for self-exclusion and direct interview with the donor themselves to gather medical and behavioral history enhances the quality of information obtained. The blood tests can be performed on fresh, good quality samples rather than post-mortem samples as is often the case with deceased donors. Tissue is procured in a clean operating theatre environment under aseptic conditions, reducing the risk of contamination. The hospitals play key role in providing donations as well as users transplanting the tissues thereby living donor programme is a collaborative process between a tissue bank and these hospitals.

BACKGROUNDChildhood cancer incidence and survivorship are both on the rise. However, many lifesaving treatments threaten the prepubertal testis. Cryopreservation of immature testicular tissue (ITT), containing spermatogonial stem cells (SSCs), as a fertility preservation (FP) option for this population is increasingly proposed worldwide. Recent achievements notably the birth of non-human primate (NHP) progeny using sperm developed in frozen-thawed ITT autografts has given proof of principle of the reproductive potential of banked ITT. Outlining the current state of the art on FP for prepubertal boys is crucial as some of the boys who have cryopreserved ITT since the early 2000s are now in their reproductive age and are already seeking answers with regards to their fertility.OBJECTIVE AND RATIONALEIn the light of past decade achievements and observations, this review aims to provide insight into relevant questions for clinicians involved in FP programmes. Have the indications for FP for prepubertal boys changed over time? What is key for patient counselling and ITT sampling based on the latest achievements in animals and research performed with human ITT? How far are we from clinical application of methods to restore reproductive capacity with cryostored ITT?SEARCH METHODSAn extensive search for articles published in English or French since January 2010 to June 2020 using keywords relevant to the topic of FP for prepubertal boys was made in the MEDLINE database through PubMed. Original articles on fertility preservation with emphasis on those involving prepubertal testicular tissue, as well as comprehensive and systematic reviews were included. Papers with redundancy of information or with an absence of a relevant link for future clinical application were excluded. Papers on alternative sources of stem cells besides SSCs were excluded.OUTCOMESPreliminary follow-up data indicate that around 27% of boys who have undergone testicular sampling as an FP measure have proved azoospermic and must therefore solely rely on their cryostored ITT to ensure biologic parenthood. Auto-transplantation of ITT appears to be the first technique that could enter pilot clinical trials but should be restricted to tissue free of malignant cells. While in vitro spermatogenesis circumvents the risk linked to cancer cell contamination and has led to offspring in mice, complete spermatogenesis has not been achieved with human ITT. However, generation of haploid germ cells paves the way to further studies aimed at completing the final maturation of germ cells and increasing the efficiency of the processes.WIDER IMPLICATIONSDespite all the research done to date, FP for prepubertal boys remains a relatively young field and is often challenging to healthcare providers, patients and parents. As cryopreservation of ITT is now likely to expand further, it is important not only to acknowledge some of the research questions raised on the topic, e.g. the epigenetic and genetic integrity of gametes derived from strategies to restore fertility with banked ITT but also to provide healthcare professionals worldwide with updated knowledge to launch proper multicollaborative care pathways in the field and address clinical issues that will come-up when aiming for the child’s best interest.