Confirmation And Function Research Of The Different Proteins Between The Cervical Posterior Longitudinal Ligaments With Ossification And The Normal Ones

Objective Ossification of the posterior longitudinal ligament (OPLL) is common in clinic, the incidence of which in Aisa old people could be 20%-34%. Hormonal and metabolic factors or hereditary factors have been proposed to involved during pathologic ligamentous ossification of the OPLL. However, the mode of inheritance and the etiology for OPLL are still obscure. There are still no definitive biomarks of OPLL that might be used to achieve an early diagnosis. Based on the results of the proteomes, to find an easier and simpler diagnostic method, and the pathogenic proteins of OPLL, and provide evidence for pharmacological research for OPLL, we analyzed cervial posterior longitudinal ligament of the COPLL (cervical ossification of posterior longitudinal ligament) and the normal ones with Real-Time Quantitive Polymerase Chain Reaction (RT-PCR) and Western-blot, in order to confirm the difference of osteoglycin (OGN) andⅥαl collagen protein on gene and protein level, and to find the marker in peripheral blood for diagnosis of the OPLL. RNA interfering (RNAi) was conducted to found the function of OGN during the ossification of the cervical ligament.Methods Cervical posterior longitudinal ligaments were collected from COPLL patients and normal subjects without COPLL. Literature review was performed to understand the function, localization of special protein or peptide of the different proteins between the COPLL and the normal ones. OGN andⅥαl collagen were chosen for further research. RT-PCR and Western-blot were also done to validate the results of differential gel electrophoresis on gene and protein level. And RT-PCR was also used to find the markers of COPLL in peripheral blood. RNAi was performed to make OGN dysfunctional in order to certify its function in COPLLResults In cervical ligaments tissue, both on gene level and protein level, OGN in COPLL patients were significantly higher (3.37 times and 5.00 times) than that in normal patients, andⅥαl collagen in normal patients were significantly higher (5.31 times and 5.14 times) than that in COPLL patients. In peripheral blood, though the trends were the same as in the tissue, the differences were not significant. After the RNAi, the COPLL cells could not to form calcic nodus under the dysfunctional OGN during the cultivation.Conclusions In cervical ligaments tissue, both on gene level and protein level, OGN in COPLL patients were significantly higher than that in normal patients, andⅥαl collagen in COPLL patients were significantly lower than that in normal patients. In peripheral blood, though the trends were the same as in the tissue, the differences were not significant, they were not able to be as the diagnostic markers of the COPLL in blood. After the RNAi, the COPLL cells could not form calcic nodus under the dysfunctional OGN during the cultivation, OGN plays an important role during the procedure of COPLL, and it could be the potential target of the biotherapy of COPLL.