Study of recombinant human osteogenic protein-1 expressed in prokaryocyte on the repair of extracted socket in rabbits.

The study investigated the effect of recombinant human osteogenic protein-1 (rhOP-1) expressed in prokaryocyte, to promote the healing of alveolar socket. A model of rabbit extracted socket into which the composites of rhOP-1 and gelatin sponge was immediately implanted was created and the osteoinduction of rhOP-1 was assessed by histological method, quantitative measurement of calcium content and alkaline phosphatase (ALP) activity. The result of histology showed that bone healing in rhOP-1 side is 4-6 weeks earlier than that of the control side. ALP activity and calcium content in rhOP-1 side were significantly high compared with that of the control side. rhOP-1 has a satisfactory osteoinduction ability to promote the healing of extracted socket.

Association Between Dentin Matrix Protein 1 (rs10019009) Polymorphism and Ankylosing Spondylitis in a Chinese Han Population from Shandong Province.

BACKGROUND: Ankylosing spondylitis (AS) is the most common rheumatic condition that is slowly progressive and predominantly affects adolescents. Pathological bone formation associated with AS is an important cause of disability. The aim of the study was to investigate the possible involvement of the genes related to endochondral ossification and ectopia ossification in genetic susceptibility to AS in a Chinese Han population. METHODS: Sixty-eight single nucleotide polymorphisms (SNPs) from 13 genes were genotyped in discovery cohorts including 300 AS patients and 180 healthy controls. The rs10019009 in dentin matrix protein 1 (DMP1) gene shown as association with AS after multiple testing corrections in discovery cohorts was replicated in a validation independent cohort of 620 AS patients and 683 healthy controls. The rs10019009 was assessed with bioinformatics including phylogenetic context, F-SNP and FastSNP functional predictions, secondary structure prediction, and molecular modeling. We performed a functional analysis of rs10019009 via reverse transcription-polymerase chain reaction, alkaline phosphatase (ALP) activity in human osteosarcoma U 2 OS cells. RESULTS: Interestingly, the SNP rs10019009 was associated with AS in both the discovery cohort (P = 0.0012) and validation cohort (P = 0.0349), as well as overall (P = 0.0004) in genetic case-control association analysis. After a multivariate logistic regression analysis, the effect of this genetic variant was observed to be independent of linkage disequilibrium. Via bioinformatics analysis, it was found that the amino acid change of the rs10019009 led to changes of SNP function, secondary structure, tertiary conformation, and splice mode. Finally, functional analysis of rs10019009 in U 2 OS cells demonstrated that the risk T allele of the rs10019009 increased enzymatic activity of ALP, compared to that of the nonrisk allele (P = 0.0080). CONCLUSIONS: These results suggested that the DMP1 gene seems to be involved in genetic predisposition to AS, which may contribute to the ectopic mineralization or ossification in AS. In addition, DMP1 gene may be a promising intervention target for AS in the future.