Role of Bacterial Biofilm in Chronic Airway Infection

1.呼吸道生物膜病的临床表现1)生物膜病侵袭性进展可以解释生物膜病侵袭性加重的机制。从生物膜中释放的漂浮型细菌将附着在呼吸道组织的其他部分。它们没有粘液-海藻酸盐，所以它们直接附着在组织上。这种直接结合对组织细胞是如此刺激，以至于它们在附着的组织上形成了新的感染性损伤。2)呼吸道生物膜病的免疫学进展藻酸盐是细菌生物膜的主要成分，在宿主体内作为抗原产生抗藻酸盐抗体。在感染后，它还在小气道局部表现出抗原抗体反应，从而导致淋巴细胞的渗透。此外，持续或反复感染促进了这些变化，由于淋巴细胞滤泡或肉芽肿样浸润物而导致气道狭窄或变形。生物膜细菌持续定植后过量的抗原形成循环中的ICs。当ICs沉积在呼吸道组织上时，补体激活的中性粒细胞与沉积的ICs的Fc部分结合，从而导致PMN的涌入和组织的破坏。大环内酯类化合物对呼吸道生物被膜病作用的基本机制14和15元大环内酯类化合物抑制藻酸盐诱导的小气道抗原抗体反应，并通过抑制细菌中藻酸盐合成途径晚期的GMD酶的活性，从而抑制细菌产生藻酸盐。因此，这些大环内酯类的作用可能会降低呼吸道生物被膜疾病中的循环免疫复合体。此外，还讨论了大环内酯类化合物抗藻酸盐作用的结构特异性。

1. Clinical Manifestation of Airway Biofilm Disease1) Invasive progress on airway biofilm diseaseThe mechanisms of invasive type exacerbation of biofilm disease can be explained. The floating type of bacteria released from biofilm will attched to other part of airway tissue. They have no mucoid-alginate, so they directly attach to tissue. Such a direct binding is so stimulant for tissue cell that they was make a new infectious lesion on attached tissue. This type of infectious exacerbation can be repeated in airway biofilm disease.2) Immunologic progress on airway biofilm diseaseAlginate, main component of bacterial biofilm, acts as an antigen to produce anti-alginate antibody in the host. It also exhibits an antigen antibody reaction locally in the small airways following infection, with resultant infiltration of lymphocytes. Furthermor, continued or repeated infection promotes these changes, leading to a narrowed or deformed airway due to lymphocyte follicules or granuloma like infiltrations. Excess antigen following persistent colonization of biofilm bactera forms circulating ICs. When the ICs deposit on the airway tissue, the complement-activated neutrophils bind to the Fc portion of deposited ICs, consequently resulting in the appearance of PMNs influx and tissue destruction due to these PMNs.2. Basic Mechanisms of Macrolide Effect on Airway Biofilm DiseaseThe 14 and 15 membered macrolide suppress the antigen antibody reaction induced by alginate at small airway area and they inhibit the alginate production from bacteria due to the inhibition of the enzymatic activity of GMD enzyme placed on late stage of alginate synthetic pathway in bacterium. Then, these macrolide effects may decrese the circulating immune complex in airway biofilm disease. Even more, structural specific of macrolide compounds for such anti-alginate action is discussed.