Quantitative and qualitative histological evaluation of different regions of cryopreserved skin derived from red-rumped agouti for obtaining cryobanks.

Abstract

Skin banks are valuable tools for the maintenance of biodiversity. The red-rumped agouti is a wild rodent of ecological importance in South America because it acts as a seed disperser, and skin banks could serve as alternatives to conserve genetic variability. Nevertheless, the most suitable skin region for forming these banks must still be determined to guarantee tissue quality after cryopreservation. We harvested skin tissues from the ear, abdominal, and inguinal regions of red-rumped agouti and evaluated the effects of cryopreservation on the quantitative and qualitative histological parameters of these somatic tissues. All tissues were evaluated for ultrastructure, skin thickness, cell count, number of perinuclear halos, collagen density, proliferative activity, and cellular ability during culture. Cryopreservation altered the thicknesses of the abdominal and inguinal dermises. Cryopreservation did not alter the number of fibroblasts and perinuclear halos in any region. The abdominal region had a higher number of fibroblasts than the other regions. All groups showed increased collagen fibers after cryopreservation, while maintaining a similar proliferative potential. During culture, all regions presented with cell viability above 90 % before and after cryopreservation, and the doubling time was maintained. However, cells from the inguinal and abdominal regions had lower metabolic rates than those from the ear. In summary, the ear skin was found to be the best region for cell recovery. However, abdominal skin has shown positive results and may be an alternative source of somatic cells.