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bioRxiv · 10.1101/2022.05.07.490875

Allogeneic testes transplanted into castrated adult medaka (Oryzias latipes) are engrafted and can function over a long period for production of donor-derived offspring by natural mating

Kayo, D.·Kanda, S.·Okubo, K.
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Abstract

Generally, successful testis transplantation has been considered to require immune suppression in the recipient to avoid rejection of the transplanted tissue. In the present study, we demonstrate in medaka that allogeneic adult testicular tissue will engraft in adult recipients immediately after partial castration without the use of immunosuppressive drugs. The allografted testes are retained in the recipients body for at least three months and are able to produce viable sperm that yield offspring after natural mating. Some recipients showed a high frequency (over 60%) of offspring derived from spermatozoa produced by the transplanted testicular tissue. Histological analyses showed that allografted testicular tissues included both germ cells and somatic cells that had established within an immunocompetent recipient testis. The relative simplicity of this testis transplantation approach will benefit investigations of the basic processes of reproductive immunology and will improve the technique of gonadal tissue transplantation.

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Kayo, D., Kanda, S., Okubo, K.. 2022-05-08. Allogeneic testes transplanted into castrated adult medaka (Oryzias latipes) are engrafted and can function over a long period for production of donor-derived offspring by natural mating. https://doi.org/10.1101/2022.05.07.490875

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