Beneficial effect of desialylated erythropoietin administration on the frozen-thawed canine ovarian xenotransplantation

Abstract

Purpose The main drawback of ovarian cryopreservation followed by transplantation is that a large proportion of follicles are lost after transplantation. Thus, effects of erythropoietin (EPO) and desialylated EPO administration on the frozen-thawed canine ovarian xenotransplantation were examined. Methods The protective and survival-promoting effects of EPO and desialylated EPO on the follicles of frozen-thawed canine ovaries after transplantation were examined using NOD-SCID mice. Frozen-thawed dog ovarian tissue with 400 U/kg of EPO or asialo EPO was placed into the ovarian bursa.Results At 4 weeks after the transplantation, the ovaries were removed and subjected to histological examination. The survival rate of early primary follicles was 15.2% in the EPO group and 157.6% in the asialo EPO group, in contrast to 10.1% in the untreated group. Conclusions These results demonstrate that administration of asialo EPO could be effectively used to enhance the survival of the follicles of transplanted cryopreserved ovaries.

Effect of graft site and gonadotrophin treatment on follicular development of canine ovarian grafts transplanted to NOD‐SCID mice

“…Thereafter, once the newly trained dogs are recognized as superior guide dogs, they can never reproduce [9][10][11].…”

Beneficial Effect of Hyperbaric Oxygen Therapy on the Follicular Survival in the Mouse Ovary after Transplantation

“…Additionally, the cryopreservation of ovarian tissues is a potentially significant technology for the preservation of the genetic resources of working dogs as well as other laboratory and domestic animals [3,4]. Several reports have indicated that follicular loss in the mammalian ovary is not drastically extended by the cryopreservation procedure itself [3][4][5]. It is believed that the reason the primordial follicle is observably resistant to cryoinjury is because the oocyte it contains has a relatively inactive metabolism and lacks a meiotic spindle, zona pellucida and cortical granules [6].…”

“…In fact, a high percentage of oocytes as well as granulosa cells survive the cryopreservation and thawing procedures [3,[7][8][9]. Despite being able to survive freezing, it is well established that a large proportion of follicles are lost during the initial ischemia that occurs after transplantation of ovaries of mouse [10,11], sheep [12,13], dog [4,5] and human [14,15]. Most follicles that survive cryopreservation undergo ischemic loss during neovascularisation [16].…”

“…However, the effect of HBO on follicular survival after ovarian tissue transplantation has not been examined to date. Thus, we examined the effect of HBO on follicular survival in the mouse ovary after transplantation as a model, since a large proportion of follicles are lost during the initial ischemia that occurs after ovarian transplantation in mammals including humans [4,5,[10][11][12][13][14][15].Eighty percent (20/25) and 65% (17/26) of transplanted ovarian tissues were recovered from recipients with and without HBO treatment at 2 weeks after transplantation, respectively. As shown in Table 1, the average numbers of primordial, primary, secondary and antral follicles in ovarian tissues of mice decreased from 3.4 ± 0.69, 3.1 ± 0.65, 5.7 ± 1.07 and 2.1± 0.67/mm 2 to 0.3 ± 0.08, 0.2 ± 0.09, 0.2 ± 0.08 and 0/mm 2 at 2 weeks after transplantation, respectively.…”

“…1). Since it has been reported that most follicles are lost during the time required for neovascularization after ovarian tissue transplantation [16], the initial treatment within 72 hr post transplantation might contribute to follicular survival.In addition to the combination of HBO and hormone treatment [4], provision of pretransplantation HBO to donors [28] might also …”