Biological Services Unit

London, United Kingdom

Biological Services Unit

London, United Kingdom

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Saso S.,Imperial College London | Petts G.,Imperial College London | Thum M.-Y.,Lister Hospital | Corless D.,Leighton Hospital | 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.


Saso S.,Hammersmith Hospital Campus | Petts G.,Imperial College London | David A.L.,University College London | Thum M.-Y.,Lister Hospital | And 10 more authors.
European Journal of Obstetrics Gynecology and Reproductive Biology | Year: 2015

Objective Uterine transplantation (UTx) has been proposed as a treatment option for women diagnosed with absolute uterine factor infertility (AUFI). The goal of UTx remains achieving pregnancy and live birth of a healthy neonate following allogeneic UTx. Our aim was to assess whether fertility was possible following allogeneic uterine transplantation (UTx), when the recipient had demonstrated long-term survival and had been administered immunosuppression. Study design Nine allogeneic UTx in New Zealand White rabbits were performed using a pre-determined protocol. Tacrolimus was the immunosuppressant selected. Embryos were transferred into both cornua of the sole living recipient via a mini-midline laparotomy. The pregnancy was monitored with regular reproductive profiles and serial trans-abdominal ultrasound to measure conceptus growth (gestation sac and crown rump length (CRL)). Results In the sole surviving doe a gestation sac was visualised on ultrasound from Day 9 (D9) after embryo transfer. Gestation sac diameter and CRL increased from D9 to D16 but by D18 the gestation sac had reduced in size. The fetus was no longer visible, suggesting fetal resorption had occurred. Subsequent scans on D22 and D25 did not demonstrate a gestation sac. Scheduled necropsy on D27 and histopathology confirmed evidence of a gravid uterus and presence of a gestational sac. A single episode of acute rejection occurred on D13. Conclusion Pregnancy was achieved after rabbit allogeneic UTx but serial ultrasound suggested that fetal demise occurred prior to scheduled necropsy. The study represents only the third example of conception and pregnancy following an animal allogeneic UTx. © 2014 Elsevier Ireland Ltd. All rights reserved.


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.


PubMed | The Lister Hospital, Southeastern Regional Medical Center, Royal Veterinary College, Biological Services Unit and 3 more.
Type: | Journal: European journal of obstetrics, gynecology, and reproductive biology | Year: 2014

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.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 g twice daily) was administered for immunosuppression post-transplant. The recipients were closely monitored until death or euthanasia.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.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.


Abi-Nader K.N.,University College London | Abi-Nader K.N.,Lebanese American University | Mehta V.,University College London | Shaw S.W.S.,University College London | And 9 more authors.
Laboratory Animals | Year: 2011

Remote telemetric monitoring of fetal haemodynamics in pregnant sheep would allow unrestricted animal movement, minimize suffering and distress, and improve animal welfare, while enhancing the quality of data collected. This may also be useful in clinical practice following fetal surgery. Using an open fetal surgical technique at approximately two-thirds of gestation, we implanted the catheter of a D70-PCTP haemodynamic telemetric device (Data Sciences International, Tilburg, The Netherlands) into the carotid artery of the fetal sheep (n = 4). The attached transmitter was secured to the posterior aspect of the maternal anterior abdominal wall. Two receivers, with a range of 1 m each, were sited in an 11 m2 sheep enclosure to maximize animal freedom while allowing continuous monitoring of the ewe. The receivers were connected by cable to a nearby computer. In the first two procedures, both fetuses died eight and 12 days after surgery, and the catheter tip was observed to be lying in the bicarotid trunk. In the next two procedures the catheter tip was threaded further upstream from the insertion point, in an attempt to reach the fetal aorta, and both fetuses survived until the scheduled postmortem examination at the end of pregnancy. After catheter implantation, fetal blood pressure (BP) and heart rate (HR) were successfully recorded continuously for seven days and then hourly per day for a further three weeks. The fetal BP and HR values were in the normal range for healthy sheep fetuses.


Saso S.,Institute of Reproductive and Developmental Biology | Hurst S.,Institute of Reproductive and Developmental Biology | Chatterjee J.,Institute of Reproductive and Developmental Biology | Kuzmin E.,Institute of Reproductive and Developmental Biology | And 10 more authors.
Journal of Obstetrics and Gynaecology Research | Year: 2014

Aim: To see if: (i) a large vessel aortocaval vascular patch technique may bring about long-term graft survival after allogeneic uterine transplantation (UTn) in a rabbit model; and (ii) fertility can be achieved following natural mating post-allogeneic UTn. Methods: Allogeneic uterine cross transplantations were performed in New Zealand white rabbits using an aortocaval macrovascular patch harvested as part of the uterine allograft. Five rabbit recipients received a uterine graft from five unrelated donor rabbits. All female rabbits were unrelated and were of proven fertility with at least one previous litter each. Tacrolimus was administrated for immunosuppression post-transplant. Natural mating was attempted if long-term survival had been achieved. The main outcome measures were: (i) long-term recipient survival; (ii) long-term adequate uterine perfusion; and (iii) successful pregnancy post-UTn. Results: All five recipient animals survived the surgery with satisfactory immediate postoperative recovery. Recipients 1, 2 and 4 died within the first 4 postoperative days. Both long-term survivors failed to conceive following introduction of a proven male breeder despite evidence of mating. Necropsy at 9 and 11 months showed a lack of patency of uterine cornua at the point of anastomosis, albeit a small uterus in recipient 3 and a reddish brown amorphous material at the site of the transplanted uterus in recipient 5. Conclusion: We have demonstrated the feasibility of uterine allotransplantation using a macrovascular patch technique, but could not demonstrate conception because of blocked cornua. To address this, we propose using embryo transfer techniques in order to achieve conception. © 2013 Japan Society 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.,Children's 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.


Avdic-Belltheus A.,Biological Services Unit
Animal Technology and Welfare | Year: 2012

Herein follows a short description of surgical procurement of germfree pigs performed under closed sterile environment and general anaesthesia. A hysterotomy was performed under the protection of a flexible film canopy in order to retrieve piglets free of microbiological organisms. The paper further describes post-surgical resuscitation and transportation of neonates as well as methods of care and housing. Procedures of sterilisation and preparation of equipment and microbiological screening are also included. The project was performed at the Royal Veterinary College, London.

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