ABSTRACT
AIM:Toinvestigatetheeffectofnicotinicacidamide(NAA)ontheinfusiondamageofhuman umbilical cord mesenchymal stem cells ( hUC-MSCs) under the condition of instant blood-mediated inflammatory reaction ( IBMIR) .METHODS:Normal peripheral blood without anticoagulant at volume of 2.7 mL was mixed with 0.3 mL phys-iological saline (as blank group), CFSE labeled hUC-MSCs (1 ×106 cells in 0.3 mL as MSC group) and CFSE labeled hUC-MSCs (1 ×106 cells in 0.3 mL) preprocessed with NAA at concentration of 10 mmol/L for 24 h ( as MSC+NAA group) , respectively.The mixture was immediately injected into the improved Chandler Loop model, placed in 37℃water bath, and then started the peristaltic pump at the speed of 20 mL/min for 1 h.The number of CFSE labeled hUC-MSCs, platelets, white blood cells were counted and the concentration of complement C3a was measured before and after cycling, respectively.RESULTS: After 1 h circulation, the platelet dissipation rate were ( 29.96 ±10.88 )% in blank group, (77.76 ±19.29)% in MSC group all and (50.13 ±18.10)% in MSC +NAA group; and the leukocyte counts were (37.82 ±13.81)%in blank group, (64.57 ±17.08)% in MSC group and (41.52 ±17.26)% in MSC+NAA group. Compared with blank group, the differences of the dissipation rates in MSC group and MSC+NAA group all had statistical significance.The hUC-MSCs relative survival rate in MSC+NAA group was higher than that in MSC group.C3a concentra-tions in blank group, MSC group and MSC+NAA group were (206.27 ±58.10), (230.47 ±39.61) and (208.37 ± 40.66) μg/L, respectively.CONCLUSION:Co-circulating the mixture of hUC-MSCs with normal peripheral blood with-out anticoagulant in the improved Chandler Loop for 1 h depletes a large number of hUC-MSCs and blood components, and increases C3a, suggesting that this model can induce IBMIR.NAA has a protective effect on the hUC-MSCs in the infusion damage by inhibiting IBMIR, reducing the wastage of the blood components and enhancing the survival rate of the hUC-MSCs.
ABSTRACT
AIM:To investigate the influence of continuous subculturing of human umbilical cord mesenchymal stem cells (hUC-MSCs) on the mRNA expression of all 23 family members of NOD-like receptors (NLRs), and to search for the way of improving the subculture quality of hUC-MSCs and increasing the quantity and safety in the experimental and clinical application .METHODS:Neonatal umbilical cord was collected to isolate and purify the hUC-MSCs with the colla-genase II digestion and adherence screening methods .These cells were continuously subcultured .The hUC-MSCs at pas-sage 3 and passage 28 were identified by flow cytometry and induced differentiation .The mRNA expression of NLRs in the passage 3 and passage 28 hUC-MSCs was detected by RT-qPCR.RESULTS: The cell phenotypes of both passage 3 and passage 28 hUC-MSCs were CD29 +/CD44 +/CD105 +/CD31 -/CD34 -/CD40 -/CD45 -/CD106 -/HLA-DR-, and both of the cells were induced into osteoblasts and adipocytes , which were conformed to the criteria of International Society for Cellular Therapy to define MSCs .All the NLR family members were expressed in passage 3 hUC-MSCs.NOD1, NLRC4, NLRC5, NLRP1, NLRP3, NLRP10, NAIP, NLRX1 and APAF1 at mRNA levels were highly expressed , and the rest were lowly expressed.When hUC-MSCs were subcultured to passage 28, NLRP10 mRNA was increased, NLRC5 mRNA and NLRX1 mRNA were hardly changed , and all of the rest members were decreased .The difference of NLRP1 mRNA expres-sion between passage 3 and passage 28 hUC-MSCs was observed with statistical significance (P<0.05).CONCLU-SION:The effects of subculturing on the expression of NLR family in hUC-MSCs are pleiotropic .It requires further investi-gation to confirm whether these effects are related to the proliferation , differentiation and immunomodulation of MSCs .