Analysis of osteoblastic gene expression in the early human mesenchymal cell response to a chemically modified implant surface: an in vitro study.
OBJECTIVE
The effect of a chemical modification of the SLA surface (SLActive surface) on human bone marrow-derived mesenchymal cells (hMSCs) on; (1) adhesion, (2) proliferation and (3) early transcriptional control of osteogenic differentiation was investigated. We are based on the hypothesis that expression patterns of genes responsible for osteogenesis might be dependent on the characteristics of the implant surface.


METHODS
hMSCs were allowed to grow on smooth (SMO-control), SLA and SLActive implant surfaces (chemically modified). Cell attachment and proliferation were assessed at 3 and 24 h using a MTT dye reduction assay. At 24 h of culture, DNA microarray analysis examined alterations in early gene expression using a human osteogenesis gene array, including 109 cDNAs in quadruplicates of major regulatory genes for osteogenesis.


RESULTS
Initial attachment and proliferation were found to be significantly reduced. Nineteen genes were significantly upregulated when hMSCs were cultured on the SLA surfaces and 27 genes were significantly upregulated when hMSCs were cultured on the SLActive surfaces. Upregulated genes control cell differentiation, signal transduction, cell cycle regulation, angiogenesis, cell adhesion and extracellular matrix and bone formation.


CONCLUSIONS
Chemical modification decreases further cell attachment and proliferation and upregulates early osteoblastic differentiation genes. Hence, a microenvironment is created around chemically modified implants that may enhance osseointegration.
Department of Periodontics, University of Texas, Health Science Center at San Antonio, USA. mamalis@uthscsa.edu
Anastasios A
AA
Mamalis
Spyridon S
SS
Silvestros
D000134:Acid Etching, Dental / Q000379:methods; D001854:Bone Marrow Cells / Q000502:physiology; D002448:Cell Adhesion / Q000502:physiology; D002453:Cell Cycle / Q000235:genetics; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D004396:Coloring Agents; D045662:Dental Etching / Q000379:methods*; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D005109:Extracellular Matrix / Q000235:genetics; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000235:genetics; D053263:Gene Regulatory Networks / Q000235:genetics; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D018919:Neovascularization, Physiologic / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D010006:Osteoblasts / Q000502:physiology*; D010012:Osteogenesis / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D013499:Surface Properties; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D014025:Titanium / Q000737:chemistry; D014158:Transcription, Genetic / Q000235:genetics; D015854:Up-Regulation / Q000235:genetics
D004396:Coloring Agents; D015921:Dental Implants; D003764:Dental Materials; D013778:Tetrazolium Salts; D013844:Thiazoles; D014025:Titanium; C022616:thiazolyl blue