Allogeneic Ovarian Transplantation Research Articles

A new strategy and system for the ex vivo ovary perfusion and cryopreservation: An innovation

Children and young adults, who suffer from cancer, receive gonadotoxic therapy, which destroys their fertile abilities after survival. Ovarian cryopreservation and transplantation provide the promising solution to this problem, where the ovary can be removed before the gonadotoxic therapy and reimplanted after patient's survival, where the ovary is to be cryopreserved during the period of the therapy. However, cryopreservation of the whole ovary is still facing great obstacles, namely the ischemic reperfusion injury and the defective cryopreservation related to the defective ability to universally deliver the cryopreservation/warming solutions through the ovarian vascular bed. Meanwhile, the currently applied technique of ovarian tissue cryopreservation provides limited follicular recovery because many follicles are lost until the development of revascularization post-transplantation. To solve the problems, an innovative system has been developed to insure immediate and universal delivery of the cryopreservation/warming solutions to the graft, in addition to keeping the graft under continuous perfusion before and after cryopreservation, minimizing any chance for microthrombi formation or ischemia-reperfusion. This innovative system can be applied in the following surgical and clinical interventions: 1) Allogeneic ovarian transplantation; 2) Preservation of fertility after systemic chemotherapy or bone marrow transplantation in young females, where the ovaries could be removed before the therapy and exposed to the adequate cryopreservation provided by the system till re-implantation after the patient's survival; 3) The system is also suitable for the corresponding applications on the testicles.

A New Strategy and System for the Ex Vivo Ovary Perfusion and Cryopreservation

Childern and young adults, who suffer from cancer, receive gonadotoxic therapy, which destroys their fertile abilities after survival. Ovarian cryopreservation and transplantation provides the promising solution to this problem, where the ovary can be removed before the gonadotoxic therapy and reimplanted after patient's survival, where the ovary is to be cryopreserved during the period of the therapy. However, cryopreservation of the whole ovary is still facing great obstacles, namely the ischemic reperfusion injury and the defective cryopreservation related to the defective ability to universally deliver the cryopreservation/warming solutions through the ovarian vascular bed. Meanwhile, the currently applied technique of ovarian tissue cryopreservation provides limited follicular recovery because many follicles are lost until the development of revascularization post-transplantation. To solve these problems, an innovative system has been developed to insure immediate and universal delivery of the cryopreservation/warming solutions to the graft, in addition to keeping the graft under continuous perfusion before and after cryopreservation, minimizing any chance for microthrombi fomation or ischemia- reperfusion. This innovative system can be applied in the following surgical and clinical interventions: 1. Allogeneic ovarian transplantation 2. Preservation of fertility after systemic chemotherapy or bone marrow transplantation in young females, where the ovaries could be removed before the therapy and exposed to the adequate cryopreservation provided by the system till re-implantation after the patient's survival. 3. The system is also suitable for corresponding applications on the testicles.

Prevention of Premature Ovarian Failure and Osteoporosis Induced by Irradiation Using Allogeneic Ovarian/Bone Marrow Transplantation

Two side effects of irradiation are premature ovarian failure (POF) and osteoporosis, both of which are concerns not only clinically, for patients, but also experimentally, for animals. We examine whether bone marrow transplantation (BMT) can correct the POF induced by radiation and also address whether allogeneic ovarian transplantation (OT) can modulate the adverse effects of radiotherapy. Eight-week-old female C57BL/6 mice were lethally irradiated with 6 Gy x2, and then injected with allogeneic bone marrow cells into their bone marrow cavity using our previously described intrabone marrow (IBM)-BMT technique. Allogeneic ovaries were simultaneously transplanted under the renal capsules of the mice. Three months after the transplantation, we noted that hematopoietic and lymphoid cells had been successfully reconstituted. The ovaries transplanted under the renal capsules demonstrated signs of development with a large number of differentiating follicles at different stages of development. Importantly, the total bone mineral density of the tibia in the "IBM-BMT+OT" (BMT/OT) group remained normal. However, the reproductive function of the recipient mice was not restored, despite the presence of many immature oocytes in the host ovaries in the BMT/OT group. In the BMT group, no oocytes were found in the host ovaries. These findings suggest that IBM-BMT with ovarian allografts can be advantageous for young women with POF and osteopenia or osteoporosis that is due to chemotherapy and radiotherapy for malignant diseases.

Prevention of Osteoporosis and Hypogonadism by Allogeneic Ovarian Transplantation in Conjunction With Intra-Bone Marrow–Bone Marrow Transplantation

We investigated the effects of ovarian allograft in conjunction with intra-bone marrow-bone marrow transplantation (IBM-BMT) on estrogen deficiency in mice. Female C57BL/6 mice underwent ovariectomy (OvX). After 3 months, the mice were irradiated at 9.5 Gy, and the bone marrow cells (BMCs) of female BALB/c mice (8 weeks old) were then injected into the bone cavity of the B6 mice. Simultaneously, allogeneic ovaries from BALB/c mice were transplanted under the renal capsules of the B6 mice. Three months after the transplantation, the hematolymphoid cells were found to be completely reconstituted with donor-derived cells. The transplanted ovary tissues under the renal capsules were accepted without using immunosuppressants; there were a large number of growing follicles at different stages of development. Atrophic endometrium and its glands were also recovered by ovarian transplantation (OT). The transplanted allogeneic ovaries secreted estrogen at normal levels. Furthermore, bone loss was prevented to a certain extent. These findings suggest that IBM-BMT+OT will become a valuable strategy for young women with malignant tumors to prevent premature senescence, including hypogonadism and osteoporosis, after radiochemotherapy.

Allogeneic Ovarian Orthotopic Transplantation in Rabbits Without a Vascular Pedicle: Morphological, Endocrinologic, and Natural Pregnancy Assessment

Background To assess the natural pregnancy of rabbits undergoing bilateral oophorectomy and determine the morphofunctional aspects of orthotopic transplantation of allogeneic intact and sliced ovarian tissue without a vascular pedicle. Methods Thirty-two female rabbits had their ovaries removed and orthotopically transplanted between the two breeds of rabbits without vascular anastomoses: group 1 ( n = 8), only laparotomy; group 2A ( n = 8) intact ovaries transplanted on both sides; group 2B ( n = 8), ovaries sliced and orthotopically transplanted; group 2C ( n = 8), an intact ovary transplanted on one side and a sliced ovary on the other side. Three months later, the animals were paired with males for copulation. We assessed estradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone levels. A histological study was performed, and the number of pregnancies and litters determined. Results Pregnancies occurred in seven rabbits of group 1; in 37.5% of rabbits in group 2A; 50% in group 2B; and 62.5% in group 2C. Hormone levels and histology confirmed the vitality of all ovaries. Conclusions Intact or sliced orthotopic allogeneic ovarian transplantations without a vascular pedicle are viable in rabbits, preserving hormonal and fertile functions.

Morphologic, endocrinologic and natural pregnancy assessment of allogeneic ovarian orthotopic transplantation without a vascular pedicle in rabbits

Objective The objective was to assess the natural pregnancy of rabbits subjected to bilateral oophorectomy and orthotopic allogeneic intact and sliced ovarian transplantation without a vascular pedicle, and to determine the morphofunctional aspects of the transplanted ovaries. Study design Thirty-two female rabbits were studied. The ovaries were removed and orthotopically transplanted without vascular anastomoses between the two breeds of rabbits. In Group 1 ( n = 8), only laparotomy and laparorrhaphy were performed, in Group 2A ( n = 8) intact ovaries were transplanted on both sides, in Group 2B ( n = 8) both ovaries were sliced and orthotopically transplanted, and in Group 2C ( n = 8) an intact ovary was transplanted on one side and a sliced ovary on the other side. Three months later, the animals were paired with males for copulation. Estradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone levels were assessed. A histologic study was carried out and the numbers of pregnancies and litters were also determined. Results Pregnancies occurred in seven rabbits in Group 1, 37.5% of rabbits in Group 2A, 50% in Group 2B, and 62.5% in Group 2C. Hormone levels and histology confirmed the vitality and function of all ovaries. Conclusions Intact or sliced orthotopic allogeneic ovarian transplantation without a vascular pedicle is viable in rabbits, and preserves their hormonal and fertile functions.

Avaliação endócrina e morfológica de transplante ovariano homógeno

INTRODUÇÃO: A insuficiência ovariana decorre de ooforectomia bilateral em diversas afecções do ovário, como neoplasia e sepse, além de quimioterapia, radiação pélvica e fatores relacionados à idade. Suas complicações sistêmicas, como insuficiências hormonais, podem ser de difícil controle. OBJETIVOS: Avaliar aspectos endócrinos e histológicos ovarianos após seu transplante ortotópico, sem anastomose vascular e submetidos à imunossupressão pela ciclosporina. MATERIAL E MÉTODO: Foram utilizadas 12 coelhas da raça Nova Zelândia Branca (n = 6) e Califórnia (n = 6), divididas em dois grupos: grupo 1 (n = 4), de controle, submetido apenas a laparotomia, sem outro procedimento cirúrgico; e grupo 2 (n = 8), submetido a ooforectomia bilateral e transplante ortotópico dos ovários, que foram trocados entre as duas raças de animais. De um lado, foi transplantado o ovário íntegro e, do outro, o ovário fatiado. Não houve anastomose vascular. As coelhas foram imunossuprimidas com ciclosporina (10mg/kg ao dia). No final do período de acompanhamento de seis meses, foram feitas dosagens de estradiol, progesterona, hormônio foliculoestimulante (FSH) e hormônio luteinizante (LH), além de estudo histológico de ovários, tuba uterina e útero. RESULTADOS: Os ovários transplantados estavam rodeados por tecido conjuntivo, bem vascularizados, mostrando folículos em diferentes estádios de desenvolvimento. A histologia tubária e uterina também foi preservada em ambos os grupos. A dosagem hormonal foi normal em todas as coelhas, indicando que, do ponto de vista endócrino, o ovário transplantado estava funcionando. O transplante ovariano homógeno ortotópico, sem pedículo vascular e submetido à imunossupressão pela ciclosporina, foi eficaz para a manutenção de hormônios ovarianos em níveis normais.

Gestação obtida em coelha após ooforectomia bilateral e transplante ovariano homógeno

OBJETIVO: Verificar a possibilidade de fertilização natural após ooforectomia total bilateral e transplante ovariano homógeno ortotópico sem anastomose vascular e imunossuprimidos pela ciclosporina. MÉTODO: Foram utilizadas dez coelhas da raça Nova Zelândia Branca e Califórnia. Realizou-se ooforectomia total bilateral e transplante ortotópico dos ovários entre pares de animais. De um lado, foi transplantado o ovário íntegro e de outro, o ovário fatiado. Não houve anastomose vascular. A imunossupressão se deu com a administração ciclosporina através de tubo orogástrico diariamente, durante seis meses. Três meses depois, as fêmeas foram colocadas diariamente para copular com machos sabidamente férteis da raça Nova Zelândia Branca, por outros seis meses. No final do período do experimento, foram realizadas dosagens de estradiol, progesterona, hormônio folículo estimulante e hormônio luteinizante, além de estudo histológico dos ovários, tubas e úteros. RESULTADOS: Gravidezes ocorreram em cinco coelhas, sendo que, em quatro delas, houve nascimento de filhotes. As dosagens hormonais estiveram dentro da faixa de normalidade em todos os animais. Os ovários transplantados estavam rodeados de tecido conjuntivos, bem vascularizados e com folículos ovarianos em vários estádios de desenvolvimento. CONCLUSÕES: Obteve-se, com sucesso, a fertilização natural e manutenção hormonal feminina em coelhas submetidas a transplante homógeno de tecido ovariano sem anastomose vascular e imunossuprimidos pela ciclosporina.