Ovarian tissue xenografting

Background: Ovarian tissue xenografting (OTX) is a procedure to obtain follicles maturation after ovarian tissue cryopreservation (OTCP). The main problem is the xenograft rejection which is still impossible to overcome at the present time. However, immune-deficient animals can be produced by genetic manipulations, and can be used as recipients for xenografts from other spieces. Materials and methods: We reviewed all the publications about ovarian tissue xenografts (11 publications between 1994 and 2001). Results: Eleven publications has been found about OTX. The results of all of them are reported. Discussion: Several immunodeficient mice and rat lines can be used as recipients (nude, Severe combined immune deficiency (SCID), NOD-SCID, hypogonadal SCID). The best results are obtained with castrated recipients. The best site for the graft is under the kidney capsule. The follicle loss seems to be more due to the graft itself, than by cryopreservation. The maximal follicle maturation that has been obtained within the grafts is early antral stage. No data are available about the final maturation stages, and the potential of oocytes xeno-matured. No animal has been produced yet with ovarian tissue xenograft. Before clinical applications could be envisaged for OTX, it is important to answer ethical questions such as: Is there a risk of transmitting infectious agents? Is there a risk of altering the human gametes genome? Will the animals produced be normal? (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.