Stemness Signature of Equine Marrow-derived Mesenchymal Stem Cells

BACKGROUND: Application of competent cells such as mesenchymal stem cells (MSCs) for treatment of musculoskeletal disorders in equine athletes is increasingly needed. Moreover, similarities of horse and human in size, load and types of joint injuries, make horse as a good model for MSCs therapy studies. This study was designed to isolate and characterize stemness signature of equine bone marrow-derived mesenchymal stem cells (BM-MSCs). METHODS: BM of three mares was aspirated and the mononuclear cells (MNCs) were isolated using density gradient. The primary MNCs were cultured and analyzed after tree passages (P3) for growth characteristics, differentiation potentials, and the expression of genes including CD29, CD34, CD44, CD90, CD105, MHC-I, MHC-II and pluripotency related genes (Nanog, Oct-4, Sox-2, SSEA-1, -3, -4) using RT-PCR or immunocytochemistry techniques. RESULTS: The isolated cells in P3 were adherent and fibroblast-like in shape with doubling times of 78.15 h. Their clonogenic capacity was 8.67±4% and they were able to differentiate to osteogenic, adipogenic and chondrogenic lineages. Cells showed expression of CD29, CD44, CD90, MHC-I and Sox-2 while no expression for CD34, MHC-II, CD105, and pluripotency stemness markers was detected. CONCLUSIONS: In conclusion, data showed that isolated cells have the basic and minimal criteria for MSCs, however, expressing only one pluripotency gene (sox-2).

Equine adipose-derived mesenchymal stem cells: phenotype and growth characteristics, gene expression profile and differentiation potentials

Because of the therapeutic application of stem cells [SCs], isolation and characterization of different types of SCs, especially mesenchymal stem cells [MSCs], have gained considerable attention in recent studies. Adipose tissue is an abundant and accessible source of MSCs which can be used for tissue engineering and in particular for treatment of musculoskeletal disorders. This study was aimed to isolate and culture equine adipose-derived MSCs [AT-MSCs] from little amounts of fat tissue samples and determine some of their biological characteristics. In this descriptive study, only 3-5 grams of fat tissue were collected from three crossbred mares. Immediately, cells were isolated by mechanical means and enzymatic digestion and were cultured in optimized conditions until passage 3 [P3]. The cells at P3 were evaluated for proliferative capacities, expression of specific markers, and osteogenic, chondrogenic and adipogenic differentiation potentials. Results showed that the isolated cells were plastic adherent with a fibroblast-like phenotype. AT-MSCs exhibited expression of mesenchymal cluster of differentiation [CD] markers [CD29, CD44 and CD90] and not major histocompatibility complex II [MHC-II] and CD34 [hematopoietic marker]. Cellular differentiation assays demonstrated the chondrogenic, adipogenic and osteogenic potential of the isolated cells. Taken together, our findings reveal that equine MSCs can be obtained easily from little amounts of fat tissue which can be used in the future for regenerative purposes in veterinary medicine

Molecular basis of differential gene expression in the mouse preimplantation embryo

Preimplantation development of the mammalian embryo consists of stages that include formation of the zygote, blastocyst formation and implantation of the embryo into the uterus. Depending on the animal, first few cleavages of the early embryo is fully supported by translation of maternal transcripts and use of maternal proteins. After this period, the preimplantation embryo starts to transcribe from its own genome and produce products, which are necessary for further development. Eventually, differential gene expression results in production of three cell types in the preimplantation embryo; an outer transporting polarized epithelium [trophoblast] and two cell types of primitive endoderm [hypoblast], and epiblast in the inner cell mass. After implantation, the trophoblast and hypoblast give rise to extra-embryonic tissues and epiblast cells form primarily the embryo proper. Expression of maternal and embryonic transcripts and proteins, and differential expression of these products that lead to differentiation of embryonic cells are all highly coordinated events, which need to be temporally and spatially regulated during this period of development. In this review article mechanisms and paradigms that may define and regulate these cellular activities leading to the first cellular differentiation of life are presented. Considering the abundance of research data on the preimplantation development of rodents, in this review we will mainly focus on the mouse model