ABSTRACT
Objective:To investigate the effects of serum from smoking individuals with periodontitis in the process of Fusobocterium.Nucleatum(Fn)invading KB cells and the expression of matrixmetalloproteinase1(MMP1)of KB cells.Methods:Serum was prepared from 10 smokers with periodontitis(group Y),10 nonsmokers with periodontitis(group N)and 5 periodontal healthy nonsmokers(group H).Serum of 200,400 and 800 μl from the subjects was added to the model of Fn invading KB cells respectively and cultured for 24 hours,the cfu of cellinvaded bacteria was estimated by colony counting.MMP1 protein level in culture supernatant wasmeasured by ELISA.Results:In the 800 μl serum groups,the percentage of invaded cfu was 12.59 ±1.27,8.03 ±0.075 and 7.99±0.14 in group Y,N and H(P <0.05)respectively,the concentration(μg/L)of MMP1 in the cultrue supernatant of group Y,Nand H was 400.04 ±21.02,252.57 ±18.89 and 262.47 ±35.29(P <0.05)respectively.In the 200 μl and 400 μl serum groups,no significant difference was detected in invasion cfu of Fn in KB cells and MMP1 secrition of KB cells among Y,N and H groups(P>0.05).Conclusion:Higher doses of smokingserum might play a role in the course of Fn invading KB cells and promote the expression of MMP1 secretion from KB cells.