利福平对结核分枝杆菌在不同植入材料界面黏附力及生物膜形成的影响

Effects of rifampicin on adhesion ability and biofilm formation of mycobacterium tuberculosis onto interfaces of different implant materials

目的通过体外实验研究利福平对结核分枝杆菌(MTB)在不同植入材料界面黏附力及生物膜形成的影响。方法随机选取钴铬钼合金、钛合金、聚乙烯样品各两块分别置入3支离心管中,加入8 m L Middlebrook7H9液体培养基,再接种初始浓度为1010CFU/m L的MTB悬液2 m L混匀,恒温(37℃)下培养30 d,从每支离心管中,随机取出一块材料,经固定、干燥、喷金后,应用扫描电子显微镜观察,比较MTB对不同植入材料的黏附力,同时观察界面生物膜形成情况。然后每支离心管中加入2 m L浓度为1μg/m L的利福平溶液,同样条件下继续培养30 d。取出材料块,经固定、干燥、喷金后,应用扫描电子显微镜观察,了解利福平对MTB黏附力的影响及对MTB生物膜的破坏情况。结果 MTB对不同植入材料界面的黏附力由强到弱依次是聚乙烯、钴铬钼、钛合金;聚乙烯界面可见生物膜形成,钴铬钼合金、钛合金界面均未见生物膜形成;利福平干预后,植入物界面黏附的菌落数显著减少,聚乙烯界面生物膜呈不同程度破坏。结论利福平能抑制MTB对不同植入材料界面的黏附及生物膜形成。

Objective To investigate the effects of rifampicin on the adhesion ability and biofilm formation of mycobacterium tuberculosis( MTB) in vitro. Methods We each selected two samples of cobalt chromium molybdenum alloy,titanium alloy and polyethylene and put them into 3 centrifuge tubes,respectively. Then,8 m L of Middlebrook7H9 culture medium and 2 m L initial concentration of 1010 cfu / m L of reinoculation of MTB suspension liquid were mixed in centrifuge tubes and cultured under the constant temperature( 37 ℃) for 30 days. We randomly took out one sample from each centrifuge tube and used scanning electron microscope for observation after fixing,drying and spraying gold on it. Then,we compared the bioadhesion ability of MTB on different implant materials and at the same time we observed interface biofilm formation. After that,adding 2 m L concentration of 1μg / m L of rifampicin solution into each centrifuge tube. Thirty days of culturing under the same condition was performed and we took out the sample. After the same procedure with former samples they were observed by scanning electron microscope,we gained a better understanding of the effect of rifampicin on the MTB adhesion force and the damage to MTB biofilm. Results The adhesion ability to polyethylene was higher than those of titanium alloy and cobalt chromium molybdenum alloy,and the adhesion ability with cobalt chromium molybdenum alloy was higher than that of titanium alloy. No biofilm forms on the interface of cobalt chromium molybdenum alloy and titanium alloy while it was available on the interface of polyethylene. After the rifampicin intervention,the number of colonies on the interface of implant reduced significantly,and the biofilm on the interface of polyethylene was destroyed to some extent.Conclusion Rifampicin can inhibit adhesion ability and biofilm formation of MTB.