Evaluation Of Osteogenic Differentiation Capacity Of Bone Marrow Mesenchymal Stem Cells In Congenital Scoliosis

Congenital scoliosis(CS)is a form of scoliosis,caused by maldevelopment of somite and consequent vertebra deformity.Characteristics of CS includes an early age of onset,severe malformation and progressing rapidly.Complications may include but are not limited to cardiopulmonary dysfunction,which could be a burden to patients and their families.Previous studies on CS etiology believed that CS is caused by a gene-environment interaction,and there is still no clear understanding about the molecular mechanism of CS.An abnormal bone metabolism in adolescent idiopathic scoliosis(AIS)has been reported,but there are few researches on bone metabolism in CS.Recently it has been reported that bone density and trabecular bone micro-architecture in CS are weaker,comparing to age-matched AIS and normal groups.The reason for the difference needs further investigation,and the correlation of lower bone marrow density and etiology of CS is worth investigated.Bone marrow mesenchymal stem cell(BMSC)has potential of multi-directional differentiation.It plays a role in bone metabolism by differentiating to osteoblasts and regulating osteoclasts production.We are trying to estimate the osteogenic differentiation capacity of CS patients' BMSCs.Hopefully we will find evidence about the mechanism of abnormal bone metabolism in CS and contribute to progress of CS etiology.ObjectsEstimate the osteogenic differentiation capacity of CS patients' bone marrow mesenchymal stem cells.Compare to normal group to find differences and gain progress on CS etiology.Methods1.Bone marrow was collected from 3 CS patients and 3 age-and-gender-matched normal adolescents.We cultured the samples to acquire mesenchymal stem cells by whole bone marrow adherent method.2.Flow cytometer were used to detect surface antigen of the samples.Then we perform an induced osteogenic differentiation and adipogenesis differentiation.Estimate the osteogenic and adipogenic capacity of the samples.3.Alizarin red was used to dye MSC on the twelfth day and eighteenth day of osteogenic differentiation.Positive area rate was measured by Image Pro Plus and calcium nodules were estimated quantitively.4.Alkaline phosphatase and bone morphogenetic protein 2 were estimated on the ninth day of osteogenic differentiation by enzyme-linked immunosorbent assay.Marker protein osteogenic differentiation during was estimated quantitively.Results1.The samples were proved to be human bone marrow mesenchymal stem cells by flow cytometer,induced osteogenic differentiation and adipogenesis differentiation.2.After alizarin red dying and measurement of Positive area rate,we found positive area rate of CS MSCs was lower than that of normal adolescents(P<0.05)on both twelfth day and eighteenth day of osteogenic differentiation.3.The amount of alkaline phosphatase of CS group is lower than that of normal group(P>0.05).The amount of Bone morphogenetic protein 2 of CS group is lower than that of normal group(P<0.05).ConclusionsOur research found the osteogenic differentiation capacity of bone marrow mesenchymal stem cells in CS was lower than that in age-and-gender-matched normal adolescents,which is reflected in a lower calcium nodules volume and a lower quantity of ALP and BMP-2 during osteogenic differentiation.This could explain the abnormal bone metabolism and congenital scoliosis etiology.