Extragonadal oocytes residing in the mouse ovarian hilum contribute to fertility

Xanthogranulomatous oophoritis with Leydig cell hyperplasia masquerading as ovarian neoplasm - A case report

ABSTRACT

Xanthogranulomatous oophoritis is an uncommon form of chronic inflammation of the ovary. Its clinical manifestations, imaging findings, and gross picture can mimic an ovarian neoplasm. Hilar cells, which are morphologically difficult to distinguish from testicular Leydig cells, secrete testosterone and they are mostly seen in the ovarian hilum. They can undergo hyperplasia or can transform into a tumor. We present a case of xanthogranulomatous oophoritis with Leydig cell hyperplasia, which mimicked an ovarian neoplasm.

Influence of graft size, histocompatibility,and cryopreservation on reproductive outcome following ovary transplantation in mice

Purpose

Transplantation of ovarian tissue is a valuable method to rescue mouse strains with fertility problems and to revitalize archived strains. The purpose of this study was to investigate the effect of (i) different sizes of transplanted ovary pieces on reproductive outcome, (ii) use of immunodeficient recipients to overcome the limitation of histocompatibility, and (iii) to compare different protocols for cryopreservation of ovarian tissue.

Methods

Halves, quarters, and eights of mouse ovaries were transplanted. Half ovaries from B6 donors were transferred into immunodeficient mice. Halves of ovaries were frozen according to four different protocols, thawed and transferred.

Results

Pregnancy rate after transplantation of ovarian tissue was high (90–100%) independent of the transplant size. Although, the average litter size was significantly lower for recipients of quarters and eights (4.4 and 4.6 vs. 6.5), the total number of offspring produced per donor ovary was higher compared with recipients of halves. Pregnancy rate of immunodeficient recipients was 40% (mean 4.7 offspring per litter). All four cryopreservation protocols used were able to preserve functionality of the ovarian tissue.

Conclusions

Transplantation of ovarian tissue smaller than halves resulted in reduced litter sizes. The distribution of ovarian tissue of one donor female to 4 or 8 recipients will therefore yield in a higher total number of offspring in a certain time period. The use of immunodeficient recipients is an option for non-histocompatible donors. Cryopreservation of ovarian tissue is generally feasible but the function of frozen-thawed ovary halves after transplantation differs depending on the freezing protocol used.