In veterinary medicine, therapeutic me
senchymal
stromal cell
s (MSC) have been traditionally i
solated from adult bone marrow or adipo
se ti
ssue. Neonatal ti
ssue
s, normally di
scarded at birth from all
specie
s have become an alternative
source of cell
s for regenerative medicine in the human clinic. The
se cell
s have been de
scribed a
s being more primitive, proliferative and immuno
suppre
ssive than their adult counterpart
s. Our objective wa
s to examine if thi
s phenomena hold
s true in dog
s. Little information exi
st
s regarding canine neonatal MSC characteri
sation. In thi
s study, we were able to both i
solate, phenotype and a
sse
ss the differentiation and immunomodulatory propertie
s of MSC from canine foetal adnexa allowing u
s to compare their characteri
stic
s to their more well-known bone marrow (BM) cou
sin
s. Neonatal ti
ssue
s, including amnion (AM), placenta (PL), and umbilical cord matrix (UCM) were collected from 6 canine cae
sarean
section
s. Primary cell
s were expanded
in vitro for 5 con
secutive pa
ssage
s and their proliferation mea
sured. BM-MSC were i
solated from 5 control dog
s euthani
sed from other
studie
s and grown
in vitro u
sing an identical protocol. All MSC line
s were
sy
stematically evaluated for their ability to differentiate into 3 me
sodermal lineage
s (adipocyte, o
steocyte and chondrocyte) and phenotyped by cytometry and qPCR. In addition, the enzymatic activity of the key immunomodulatory marker indoleamine 2,3-dioxygena
se (IDO) wa
s evaluated for each MSC line.
spar0050">MSC displaying a fibroblastic appearance were successfully grown from all neonatal tissues. PL-MSC exhibited significantly higher proliferation rates than AM- and UCM–MSC (p = 0.05). Cytometric analysis showed that all MSC express CD90, CD29, and CD44, while no expression of CD45, CD34 and MHC2 was detected. Molecular profiling showed expression of CD105 and CD73 in all MSC. Low levels of SOX2 mRNA was observed in all MSC, while neither NANOG, nor OCT4 were detected. All MSC differentiate into 3 mesodermal lineages. Following inflammatory stimulation, the activity of the immunomodulatory enzyme IDO was significantly higher in neonatal MSC compared to BM-MSC (p = 0.009).
spar0055">Our results show that canine foetal adnexa cells share very similar properties to their adult equivalents but upon stimulation show significantly higher IDO immunomodulatory activity. Further studies will be needed to confirm the potential therapeutic benefits of these cells.