The 5th and last day of the Training School started with the conference of Dr. Catherine Labbé (INRA, Rennes, France) entitled “Diploid genome preservation and regeneration: the strength and pitfalls of isolated embryonic and somatic cells”, in which she talked about how somatic cell cryopreservation is an alternative to store complete genome of an individual (and not only an haploid set as in the case of sperm), which can also be obtained independently from the reproductive cycle of the species of interest (contrarily to the case of primordial germ cells, PGCs, or spermatogonias).
The second part of her presentation was based on techniques for cellular transplant (cloning) necessary to obtain a fish from cells not destined to complete the reproductive cycle. She paid special attention to how epigenetic factors are involved in the re-programming of a somatic cell in an embryonic cell.
With some technical difficulties, finally Dr. Samyra Lacerda (Universidad Federal de Minas Gerais, Brasil) could make send, under a format of several videos, her presentation entitled “Germ cell transplantation as a potential biotechnological approach to fish reproduction”, based on different modalities of PGCs transplant applied in fish and their potential future applications. We had the chance to contact her by skype and thank her collaboration.

The workday was closed with the last practical session, entitled “Usefulness of cryopreserved material: microinjection of post-thaw germ cells”, where Dr. Elsa Cabrita and Dr. Vanesa Robles performed a demonstration of how to microinject cells in sole larvae, as a logical continuation of the practical session of the day before, in which fragments of testicular tissue were frozen. For cell transplanting, frozen testicular tissue has to be thawed and enzimatically dispersed, to obtain cells which can be microinjected.
With this, the Training School finished. According to the surveys, the general feeling was that students enjoyed their participation in this Training School. All of us were happy with the organization, with the quality of presentations by invited trainers and with the kindness of ICMAN-CSIC staff, especially Dr. Elsa Cabrita.