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Saso S.,Imperial College London | Petts G.,Imperial College London | Chatterjee J.,Imperial College London | Thum M.-Y.,Lister Hospital | And 8 more authors.
European Journal of Obstetrics Gynecology and Reproductive Biology | Year: 2014

Objective Uterine transplantation (UTx) has been proposed as a treatment option for women diagnosed with absolute uterine factor infertility. Allogeneic UTx has been attempted in a number of animal models, but achieving an adequate blood supply for the transplanted uterus still presents the biggest challenge. Microvascular re-anastomosis was unsuccessful in a number of animal models. The aim was to assess whether a large vessel aortic-caval vascular patch technique can bring about long-term graft survival after allogeneic UTx in a rabbit model. Study design A longitudinal study involving uterine cross transplantations (n = 9 donors, n = 9 recipients) was performed in New Zealand white rabbits using an aortic-caval macrovascular patch harvested as part of the uterine allograft. All rabbits were allogeneic and of proven fertility, with at least one previous litter each. The end result of the donor graft harvest was a total hysterectomy transecting across the vagina and the most lateral aspects of the uterine horns together with an aortic-caval macrovascular patch (aorta, inferior vena cava, common and internal iliacs, and uterine arterial and venous tree). Tacrolimus (500 μg twice daily) was administered for immunosuppression post-transplant. The recipients were closely monitored until death or euthanasia. Results In this case series, long-term rabbit survival was 11% (n = 1). Surgical survival was 56% (n = 5). Three rabbits (UTx #3, #4 and #8) died intra-operatively as a result of blood aspiration, ventricular hematoma, and massive hemorrhage. Three does (#1, #2, #7 and #9) died within the first 24 h as a result of the veno-vena and anastomosis breakdown. Does #6 and #9 died secondary to pre-operative pneumonia and a pulmonary embolus, respectively. Only one rabbit survived longer than a month. Conclusion Our method used a macrovascular patch technique to ensure adequate blood supply to the donor uterine graft. We have demonstrated the feasibility of uterine allotransplantation using this technique in the rabbit, but were unable to demonstrate a higher long-term survival percentage because of issues related to using a rabbit model. © 2014 Elsevier Ltd. All rights reserved.

Saso S.,Imperial College London | Petts G.,Imperial College London | Thum M.-Y.,Lister Hospital | Corless D.,Mid Cheshire NHS Trust | And 5 more authors.
Acta Obstetricia et Gynecologica Scandinavica | Year: 2015

Objective. To investigate, develop and evaluate anatomical, surgical and anastomotic aspects necessary for a successful uterine transplant in a large-animal model. Design. Sheep model; longitudinal study involving five ewes. Setting. Royal Veterinary College, London, UK. Population. Five ewes of proven fertility. Methods. The uterine allograft along with the internal iliacs, and uterine arterial and venous tree all intact were harvested en bloc. An end-to-side anastomosis was performed between the external iliac vessels and the internal iliac vessels of the graft using 6-0 polypropylene. Successful reperfusion of the graft was initially judged by the color shift of the uterus during reperfusion. Blood flow past the venous and arterial anastomotic sites was also ensured by visual inspection, together with pulse oximetry and multispectral imaging. Main outcome measures. Operative details (retrieval, ischemic, clamping, reperfusion and recipient hysterectomy duration); physiological profiles; gross morphology and histopathology. Results. Five autotransplants were performed. One procedure was abandoned because of the inappropriate size of sheep model. Another procedure was halted because the animal suffered from respiratory failure in the immediate intra-operative period. Three transplants were completed. In those, at least two of four possible anastomoses were finished and the grafted uteri demonstrated immediate perfusion and appropriate viability 45 min post-operatively. Conclusions. Internal to external iliac vessel anastomoses are an acceptable surgical technique that should be applied in a human model to ensure adequate subsequent uterine perfusion. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

David A.L.,University College London | McIntosh J.,University College London | Peebles D.M.,University College London | Cook T.,Imperial College London | And 7 more authors.
Human Gene Therapy | Year: 2011

Somatic in utero gene therapy aims to treat congenital diseases where pathology develops in perinatal life, thereby preventing permanent damage. The aim of this study was to determine whether delivery of self-complementary (sc) adeno-associated virus (AAV) vector in utero would provide therapeutic long-term transgene expression in a large animal model. We performed ultrasound-guided intraperitoneal injection of scAAV2/8-LP1-human Factor IX (hFIX)co (1×1012 vector genomes/kg) in early (n=4) or late (n=2) gestation fetal sheep. The highest mean hFIX levels were detected 3 weeks after injection in late gestation (2,055 and 1,687.5ng/ml, n=2) and 3 days after injection in early gestation (435ng/ml, n=1). Plasma hFIX levels then dropped as fetal liver and lamb weights increased, although low levels were detected 6 months after late gestation injection (75 and 52.5ng/ml, n=2). The highest vector levels were detected in the fetal liver and other peritoneal organs; no vector was present in fetal gonads. hFIX mRNA was detectable only in hepatic tissues after early and late gestation injection. Liver function tests and bile acid levels were normal up to a year postnatal; there was no evidence of liver pathology. No functional antibodies to hFIX protein or AAV vector were detectable, although lambs mounted an antibody response after injection of hFIX protein and Freund's adjuvant. In conclusion, hFIX expression is detectable up to 6 months after delivery of scAAV vector to the fetal sheep using a clinically applicable method. This is the first study to show therapeutic long-term hFIX transgene expression after in utero gene transfer in a large animal model. © 2011 Mary Ann Liebert, Inc.

Abi-Nader K.N.,University College London | Boyd M.,Biological Services Unit | Flake A.W.,Childrens Hospital of Philadelphia | Mehta V.,University College London | And 2 more authors.
Methods in Molecular Biology | Year: 2012

Large animal experiments are vital in the field of prenatal gene therapy, to allow translation from small animals into man. Sheep provide many advantages for such experiments. They have been widely used in research into fetal physiology and pregnancy and the sheep fetus is a similar size to that in the human. Sheep are tolerant to in utero manipulations such as fetoscopy or even hysterotomy, and they are cheaper and easier to maintain than non-human primates. In this chapter, we describe the animal husbandry involved in generating time-mated sheep pregnancies, the large number of injection routes in the fetus that can be achieved using ultrasound or fetoscopic-guided injection, and laparotomy when these more minimally invasive routes of injection are not feasible. © 2012 Springer Science+Business Media, LLC.

Abi-Nader K.N.,University College London | Mehta V.,University College London | Wigley V.,University College London | Filippi E.,University College London | And 4 more authors.
Reproductive Sciences | Year: 2010

Accurate noninvasive quantification of volume blood flow in the uterine arteries (UtAs) would have clinical and research benefits. We evaluated the correlation and agreement between uterine artery volume blood flow (UtABF) as calculated (cUtABF) from color/pulsed-wave Doppler acquisitions and that measured (mUtABF) by bilateral perivascular transit-time flow probes in 6 pregnant sheep at 2 gestational ages. Out of 22 Doppler acquisitions, 19 were successful. The overall correlation between cUtABF and mUtABF was 0.55 (n = 19, P =.01). Calculated UtABF and mUtABF were significantly correlated in late gestation (n = 11, r = 0.71, P =.01) but not at mid-gestation (n = 8, r =.02, P =.96). By Bland-Altman analysis, the mean cUtABF/mUtABF was 1.15 with 95% limit of agreement (-0.26 to 2.56), similar to results previously achieved using power/pulsed-wave Doppler. Despite the acceptable correlation, the limits of agreement between Doppler and transit-time flow probe measurements remain wide. This makes Doppler ultrasonography less than a desirable method to quantify UtABF in studies where accurate quantification is required.

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