Donlan Rodney M, Costerton J William
Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Clin Microbiol Rev. 2002 Apr;15(2):167-93. doi: 10.1128/CMR.15.2.167-193.2002.
Though biofilms were first described by Antonie van Leeuwenhoek, the theory describing the biofilm process was not developed until 1978. We now understand that biofilms are universal, occurring in aquatic and industrial water systems as well as a large number of environments and medical devices relevant for public health. Using tools such as the scanning electron microscope and, more recently, the confocal laser scanning microscope, biofilm researchers now understand that biofilms are not unstructured, homogeneous deposits of cells and accumulated slime, but complex communities of surface-associated cells enclosed in a polymer matrix containing open water channels. Further studies have shown that the biofilm phenotype can be described in terms of the genes expressed by biofilm-associated cells. Microorganisms growing in a biofilm are highly resistant to antimicrobial agents by one or more mechanisms. Biofilm-associated microorganisms have been shown to be associated with several human diseases, such as native valve endocarditis and cystic fibrosis, and to colonize a wide variety of medical devices. Though epidemiologic evidence points to biofilms as a source of several infectious diseases, the exact mechanisms by which biofilm-associated microorganisms elicit disease are poorly understood. Detachment of cells or cell aggregates, production of endotoxin, increased resistance to the host immune system, and provision of a niche for the generation of resistant organisms are all biofilm processes which could initiate the disease process. Effective strategies to prevent or control biofilms on medical devices must take into consideration the unique and tenacious nature of biofilms. Current intervention strategies are designed to prevent initial device colonization, minimize microbial cell attachment to the device, penetrate the biofilm matrix and kill the associated cells, or remove the device from the patient. In the future, treatments may be based on inhibition of genes involved in cell attachment and biofilm formation.
尽管生物膜最早是由安东尼·范·列文虎克描述的，但描述生物膜过程的理论直到1978年才得以发展。我们现在了解到生物膜是普遍存在的，存在于水生和工业水系统以及大量与公共卫生相关的环境和医疗设备中。利用扫描电子显微镜以及最近的共聚焦激光扫描显微镜等工具，生物膜研究人员现在明白生物膜并非无结构的、均匀的细胞沉积物和累积的黏液，而是由包含开放水通道的聚合物基质包裹的与表面相关的细胞组成的复杂群落。进一步的研究表明，生物膜表型可以根据与生物膜相关的细胞所表达的基因来描述。在生物膜中生长的微生物通过一种或多种机制对抗菌剂具有高度抗性。已证明与生物膜相关的微生物与几种人类疾病有关，如天然瓣膜心内膜炎和囊性纤维化，并能在各种各样的医疗设备上定殖。尽管流行病学证据表明生物膜是几种传染病的来源，但与生物膜相关的微生物引发疾病的确切机制仍知之甚少。细胞或细胞聚集体的脱落、内毒素的产生、对宿主免疫系统抗性的增加以及为抗性生物体的产生提供一个生态位，都是可能引发疾病过程的生物膜过程。预防或控制医疗设备上生物膜的有效策略必须考虑到生物膜独特而顽强的性质。当前的干预策略旨在防止器械最初被定殖、尽量减少微生物细胞附着于器械、穿透生物膜基质并杀死相关细胞，或从患者身上移除器械。未来，治疗可能基于抑制参与细胞附着和生物膜形成的基因。
