Comparison Of MSCs From Different Sources In Chicken And Variation Of CD4~+CD25~+ T Cells In Chimeras Prepared With Selected MSCs

Mesenchymal stem cells(MSCs)are of various functions,such as being capable to involve in the immunoregulation by suppressing the effector T cells and promoting the proliferation of the regulatory T cell(Treg).CD4~+CD25~+ T cells in poultry were of similar function with Tregs in mammal,while reports about the interaction of exogenous MSCs and CD4~+CD25~+ T cell in poultry were limited.Chimeras are a kind of favorable model to study the migration of exogenous cells and immune tolerance.In this paper,an inter specific model,i.e.the Peking duck-White Leghorn chimeras was developed with the bone marrow-MSCs of Peking duck as donor.The migration of donor in the acceptor and the variation of the CD4~+CD25~+ T cell in poultry chimeras were researched.MSCs could be obtained from a very wide sources,while the comparison between MSCs from different sources in poultry was limited.In in this paper,we compared the biological characteristics of MSCs derived from four different sources(i.e.,bone marrow,adipose tissue,umbilical cord and spleen of the poultry).Results showed that the morphologies of the four target MSCs cultured in vitro were basically in accordance.The expressions of several selected surface markers were also similar,i.e.,the CD29,CD44,CD71,CD90,and CD 105 marker were positively expressed,while the CD31,CD34,and CD45 marker were negatively expressed.The relative expression quantity of the positive-expressed surface markers detected with fluorescent quantitative real time polymerase chain reaction were in difference,which may affect on the function of different MSCs.Results from the growth kinetics and cell migration showed that the growth rate and migration capabilities of MSCs from spleen appeared a decrease compared with those from bone marrow,while those from adipose tissue and umbilical cord showed a similar curve with those from bone marrow.Results from the differentiation experiments in vitro showed that all the four MSCs derived from different sources could be differentiated into osteoblasts and adipocytes in vitro,but the expression quantity of the relevant markers was in difference.MSCs from bone marrow were proned to be differentiate into osteoblast,while MSCs from spleen were easily induced into adipocytes.This difference could be attributed to the different relevant expression quantity of the target genes in the four sources.A homologous allograft injection was performed,and a relatively low immunogenicity was observed.In conclusion,MSCs derived from bone marrow were with an excellent comprehensive property,while MSCs derived from adipose tissue were a little worse than MSCs from bone marrow,but with a wide application potential.MSCs derived from spleen performed worst in the four selected sources.Based on the above results,MSCs from bone marrow of Peking duck(dBM-MSCs)were selected for the preparation of the Peking duck-White Leghorn chimeras.dBM-MSCs were selected as donor cells and fluorescent-marked by lentivirus infection and PKH26 staining.The migration of marked dBM-MSCs in accecpor was observed.Results showed that dBM-MSCs could migrate into numerous tissues and organs,and survive in vivo,indicating a candidate for the preparation of chimeras.The chimeras were observed with GFP and detected via PCR.The specific genes from donor could be detected in the chimeras,suggesting a successful of chimeras development.In this paper,about 17%of the target chimeras succeeded.Variation of the CD4~+CD25~+ T cell was studied in the chimeras.In the 1-day-old chimeras,the migration of CD4~+CD25~+ T cells was observed from the thymus to the spleen and cecal tonsils,with bursa of Fabricius absent in this migration.This migration was more obvious in the chimeras than in the control group,suggesting the enhancement of migration by the donor cells,dBM-MSCs.In the test of the 7-and 30-day-old chimeras,it was found that the specific CD4~+CD25~+ T cells in thymus and spleen of chimeras was in accordance with that of control group,while the specific CD4~+CD25~+ T cells in cecal tonsils of chimeras showed a significant increase compared to that of control group.But the increase trend was gradually decreased with time throughout the experimental period.A similar change was also observed in the variation of the target cytokines,IL-10 and TGF-?,indicating a possible revalent between the expression of IL-10 and TGF-? and the variation of the he CD4~+CD25~+ T cell ratio.In summary,MSCs from four different sources were compared,and an inter specific chimera of was successfully developed with the selected dBM-MSCs,which could be a favorable model for the study on the effect of MSCs on CD4~+CD25~+ T cell.The variation of specific CD4~+CD25~+ T cell in the chimera was tested in this paper,supporting a theoretical basis on the cure immunity related diseases.