Department of Biomedical, Surgical and Dental Sciences, University of Milan, Italy.
Department of Medical Biotechnology and Translational Medicine, University of Milan, Italy.
Cytotherapy. 2014 Feb;16(2):181-90. doi: 10.1016/j.jcyt.2013.11.009.
Traditional antibiotic therapy is based on the oral or systemic injection of antibiotics that are often unable to stop a deep infection (eg, osteomyelitis). We studied whether or not bone marrow stromal cells (BM-MSCs) are able to uptake and release ciprofloxacin (CPX), a fluoroquinolone considered the drug of choice for the treatment of chronic osteomyelitis because of its favorable penetration into poorly vascularized sites of infection.
Human bone marrow stromal cells (BM-MSCs) were primed with CPX (BM-MSCsCPX) according to a methodology previously standardized in our laboratory for paclitaxel (PTX). The anti-microbial activity of CPX released from BM-MSCs cells (BM-MSCsCPX-CM) or supernatant from cell lysate (BM-MSCsCPX-LYS) was evaluated by agar dilution and microdilution methods on three bacterial strains (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa). To investigate whether or not primed cells (BM-MSCsCPX) were able to directly act on the bacterial growth, co-colture was performed by mixing E. coli suspension to an increasing number of BM-MSCsCPX. The anti-bacterial activity was determined as number of BM-MSCsCPX that completely inhibited bacterial growth.
The results demonstrated that BM-MSCsCPX are able to uptake and then release CPX in the conditioned medium. The loaded antibiotic maintains its active form throughout the process as tested on bacteria.
Our findings suggest that CPX-loaded MSCs may represent an important device for carrying and delivering CPX (and perhaps other antibiotics) into infected deep microenvironments; they could be used for local application and by systemic infusion when their homing capacity into the bone is cleared.
传统的抗生素治疗基于口服或全身注射抗生素，而这些抗生素往往无法阻止深部感染（例如骨髓炎）。我们研究了骨髓基质细胞（BM-MSCs）是否能够摄取和释放环丙沙星（CPX），CPX 是一种氟喹诺酮类药物，由于其对感染部位血供不良的良好穿透性，被认为是治疗慢性骨髓炎的首选药物。
根据我们实验室先前标准化的紫杉醇（PTX）方法，用 CPX 对人骨髓基质细胞（BM-MSCs）进行预加载（BM-MSCsCPX）。通过琼脂稀释和微量稀释法，评估 CPX 从 BM-MSCs 细胞（BM-MSCsCPX-CM）或细胞裂解物上清液（BM-MSCsCPX-LYS）释放的抗微生物活性，用于三种细菌菌株（金黄色葡萄球菌、大肠杆菌和铜绿假单胞菌）。为了研究预加载的细胞（BM-MSCsCPX）是否能够直接作用于细菌生长，通过将大肠杆菌悬液混合到越来越多的 BM-MSCsCPX 中进行共培养。通过完全抑制细菌生长的 BM-MSCsCPX 的数量来确定抗细菌活性。
结果表明，BM-MSCsCPX 能够摄取 CPX，然后在条件培养基中释放 CPX。负载抗生素在整个过程中保持其活性形式，在细菌上进行测试。
我们的研究结果表明，CPX 负载的 MSC 可能代表一种携带和输送 CPX（也许还有其他抗生素）进入感染深部微环境的重要装置；当它们向骨骼归巢的能力得到明确时，它们可以用于局部应用和全身输注。
