使用兩種能辨識不同微生物表面結構之噬菌體以移除小鼠腸道中耐碳青黴烯類抗生素的克雷伯氏肺炎桿菌

Abstract

克雷伯氏肺炎桿菌是人類胃腸道微生物群的正常組成部分，但是在某些情況下它可能會導致疾病。過去20年來，抗抗生素細菌的盛行率不斷增加，例如抗碳青黴烯類克雷伯氏肺炎桿菌。因此我們試圖從具有人類腸道微生物群的小鼠模型中針對性消除抗碳青黴烯類克雷伯氏肺炎桿菌。為了建立人源化微生物群定植小鼠腸道中，我們透過糞便微生物移植將含有K64莢膜型的抗碳青黴烯類克雷伯氏肺炎桿菌及人類微生物群餵食無菌小鼠。然後，我們使用兩種噬菌體，一種針對克雷伯氏肺炎桿菌的莢膜（φK64-1），一種針對克雷伯氏肺炎桿菌的O1脂多醣（φKO1-1），用以消除腸道中的抗碳青黴烯類克雷伯氏肺炎桿菌。在未處理的對照組和經φKO1-1治療的K64莢膜型的抗碳青黴烯類克雷伯氏肺炎桿菌定植小鼠中，沒有觀察到抗碳青黴烯類克雷伯氏肺炎桿菌的變化，而在經φK64-1治療的小鼠中，觀察到短暫的抗碳青黴烯類克雷伯氏肺炎桿菌消除。在同時接受φKO1-1和φK64-1治療的一半小鼠中，透過聚合酶連鎖反應和培養的方式在噬菌體治療56天後的試驗小鼠新鮮糞便中，檢測不到抗碳青黴烯類克雷伯氏肺炎桿菌。但是在另外一半的試驗小鼠中，抗碳青黴烯類克雷伯氏肺炎桿菌暫時消除，但在噬菌體治療35天後恢復。φK64-1和φKO1-1聯合治療中，使52.3%攜帶抗碳青黴烯類克雷伯氏肺炎桿菌的試驗小鼠腸道內，實現了噬菌體治療後的56天抗碳青黴烯類克雷伯氏肺炎桿菌的去定植。值得一提的是，在噬菌體治療後腸道微生物群的組成並沒有很顯著的改變。因此，這種策略不僅可用於根除腸道微生物群中的抗藥性細菌種類，還可能用於治療其他與菌叢失調相關的疾病。

Klebsiella pneumoniae is a normal component of the human gastrointestinal tract microbiota. However, in some cases, it can cause disease. Over the past 20 years, the prevalence of antibiotic-resistant bacteria, such as carbapenem-resistant K. pneumoniae (CRKP), has been increasing. We attempted to specifically eliminate CRKP from a mouse model with the human intestinal microbiota. To establish humanized microbiota-colonized mice, we administered K64 CRKP-containing human microbiota to germ-free mice by fecal microbiota transplantation. Then, we used two phages, one targeting the capsule (φK64-1) and one targeting O1 lipopolysaccharide (φKO1-1) of K64 K. pneumoniae, to eliminate CRKP. In untreated control and φKO1-1-treated K64-colonized mice, no change in CRKP was observed, while in mice treated with φK64-1, a transient reduction was observed. In half of the mice treated with both φKO1-1 and φK64-1, CRKP was undetectable in feces by PCR and culture for 56 days. However, in the other 50% of the mice, K. pneumoniae was transiently reduced but recovered 35 days after treatment. Combination treatment with φK64-1 and φKO1-1 achieved long-term decolonization in 52.3% of mice carrying CRKP. Importantly, the composition of the intestinal microbiota was not altered after phage treatment. Therefore, this strategy may be useful not only for eradicating drug-resistant bacterial species from the intestinal microbiota but also for the treatment of other dysbiosis-associated diseases.