Establishment and characterization of fibroblast cultures derived from a female common hippopotamus (Hippopotamus amphibius) skin biopsy.

The population decline of the common hippopotamus (Hippopotamus amphibius) has necessitated the preservation of their genetic resources for species conservation and research. Of all actions, cryopreservation of fibroblast cell cultures derived from an animal biopsy is considered a simple but efficient means. Nevertheless, preserving viable cell cultures of the common hippopotamus has not been achieved to our knowledge. To this end, we established and characterized fibroblast cell cultures from the skin sample of a newborn common hippopotamus in this study. By combining the tissue explant direct culture and enzymatic digestion methods, we isolated a great number of cells with typical fibroblastic morphology and high viability. Neither bacteria/fungi nor mycoplasma was detectable in the cell cultures throughout the study. The population doubling time was 34 h according to the growth curve. Karyotyping based on Giemsa staining showed that the cultured cells were diploid with 36 chromosomes in all, one pair of which was sex chromosomes. The amplified mitochondrial cytochrome C oxidase subunit I gene sequence of the cultured cells was 99.26% identical with that of the registered H. amphibius complete mitochondrial DNA, confirming the species of origin of the cells. Flow cytometry and immunofluorescence staining results revealed that the detected cells were positive for fibroblast markers, S100A4, and vimentin. In conclusion, we generated the fibroblast cell cultures from a common hippopotamus and identified their characteristics using multiple techniques. We believe the cryopreserved cells could be useful genetic materials for future research.

Establishment and characterization of a fibroblast cell line from postmortem skin of an adult Chinese muntjac (Muntiacus reevesi).

Isolation and culture of somatic cells from animals especially endangered species have raised great concerns as it is being an effective and convenient way to preserve genetic materials for future studies. As a species native to China, Chinese muntjac (Muntiacus reevesi) is listed as a beneficial species with economic and scientific research values. To our knowledge, however, there have been no published reports on somatic cell preservation of this species to date. To conserve biological resources for sustainability of Chinese muntjacs' genetic diversity, we established a fibroblast cell line from the postmortem ear skin of an adult male Chinese muntjac. The cultured cells were adherent to the plastic and showed an elongated, thin, and spindle-like shape. Moreover, they were FSP1- and VIM-positive characterizing them to be fibroblastic. No microorganisms (bacteria, fungi, or mycoplasmas) were detected throughout the whole study. Cell viability was high although it declined somehow after passaging. The population doubling time was 21.28 h according to the growth curve. Chromosome analysis revealed that the established fibroblast cell line contained 23 pairs of chromosomes, one pair of which was sex chromosomes (XY). Mitochondrial cytochrome C oxidase I gene of cultured cells shared 98.32% identity with those of Muntiacus reevesi registered in GenBank, which verified the cell line was derived from Muntiacus reevesi. In conclusion, we propagated and characterized fibroblast cells from a Chinese muntjac. We believe that this somatic cell line could facilitate animal cloning and breeding studies and become a useful in vitro model to address genetic questions.

Transcriptome variations among human embryonic stem cell lines are associated with their differentiation propensity.

Human embryonic stem cells (hESCs) have the potential to form any cell type in the body, making them attractive cell sources in drug screening, regenerative medicine, disease and developmental processes modeling. However, not all hESC lines have the equal potency to generate desired cell types in vitro. Significant variations have been observed for the differentiation efficiency of various human ESC lines. The precise underpinning molecular mechanisms are still unclear. In this work, we compared transcriptome variations of four hESC lines H7, HUES1, HUES8 and HUES9. We found that hESC lines have different gene expression profiles, and these differentially expressed genes (DEGs) are significantly enriched in developmental processes, such as ectodermal, mesodermal and endodermal development. The enrichment difference between hESC lines was consistent with its lineage bias. Among these DEGs, some pluripotency factors and genes involved in signaling transduction showed great variations as well. The pleiotropic functions of these genes in controlling hESC identity and early lineage specification, implicated that different hESC lines may utilize distinct balance mechanisms to maintain pluripotent state. When the balance is broken in a certain environment, gene expression variation between them could impact on their different lineage specification behavior.