reported that such MSCs can be unavoidably contaminated with hematopoietic cells or other mononuclear cells [13], [14]. MSCs are generally considered to be CD29-, CD71-, and CD90-positive. Therefore, the surface markers of human MSCs might differ from those of other species. Rabbit bone marrow MSCs were obtained that experienced a multi-differentiation potential. The phenotype of these Nivocasan (GS-9450) cells was analyzed using circulation cytometry antibodies for 25 rabbit surface markers, namely, CD13, CD14, CD29, CD31, CD34, Nivocasan (GS-9450) CD44, CD45, CD49d, CD49f, CD51, CD54, CD59, CD71, CD73, CD90, CD105, CD106, CD133, CD166, MHC I, MHC II, -easy muscle mass actin (-SMA), cytokeratin, desmin, and vimentin. The phenotype of commercially available human MSCs was similarly analyzed using antibodies for human surface markers. CD14, CD31, CD34, CD45, CD49d, CD49f, CD51, CD54, CD71, CD106, CD133, MHC II, and cytokeratin were absent from both rabbit and human MSCs, while CD44, -SMA, and vimentin were present on both cell lines. CD13, CD29, CD59, CD73, CD90, CD105, CD166, and MHC I were present on human MSCs, but not on rabbit MSCs. However, desmin was present on rabbit MSCs, but not on human MSCs. In total, the surface expression of nine markers differed between human Nivocasan (GS-9450) and rabbit MSCs, whereas the surface expression of 16 markers was the same in the two cell lines. Introduction Biological and Nivocasan (GS-9450) clinical desire for mesenchymal stem cells (MSCs) has increased dramatically over the past two decades [1], [2]. MSCs are multipotent cells that can replicate and have the potential to differentiate into cells of mesenchymal lineages, including bone, cartilage, and excess fat [2]. According to a report by Pittenger et al., human MSCs are characterized by the presence of particular marker proteins on their surface, including CD29, CD44, CD71, CD90, and CD105, and by the absence of marker proteins of leukocytes and cells of hematopoietic lineage, including CD14, CD34, and CD45 [2]. However, Peister et al. reported that murine MSCs do not express CD90 [3], Lapi et al. reported that rabbit MSCs do not express CD90 [4], and Karaoz et al. reported that rat MSCs do not express CD71 [5]. Our previous study showed that rabbit MSCs are CD29- and CD90-unfavorable [6]. Martnez-Lorenzo et al. found species-related differences in the phenotypes of MSCs from human, rabbit, and sheep [7]. Although this suggests that surface markers are not the same on human MSCs as on MSCs of other species, the number of surface markers analyzed by Peister et al. and Lapi et al. was relatively small (10 and 11, respectively) [3], [4]. Karaoz et al. only analyzed rat MSCs, and did not compare rat and human MSCs [5]. Martnez-Lorenzo et al. analyzed 18 MSC markers of humans and other species. However, many of these markers were only expressed by 10C70% of MSCs; therefore, it is Rabbit Polyclonal to CDH7 unclear whether these markers are expressed by MSCs of these species [7]. Therefore, in this study, we used a large number of antibodies to determine whether a range of markers are present or absent on the surface of rabbit and human MSCs. Expression of each surface marker was analyzed on MSCs at passage 3 using circulation cytometry, which were repeated four occasions. The mean percentage of human or rabbit MSCs that expressed the surface marker was decided. To definitively determine whether the protein was present or absent from the surface of human or rabbit MSCs, only antibodies that were advertised as being reactive against the human and/or rabbit surface markers were used. Therefore, we provided values (percentage of cells labeled by a marker) fulfilled or close to fulfilling Dominici’s criteria to define MSCs as being positive or unfavorable for the given markers. Materials and Methods Ethics statement All animals were cared for in strict accordance with the recommendations of the Guide for.