摘要
目的观察棘阿米巴原虫对霍乱弧菌O139的环境生存影响。方法采用共培养方法, 通过染色和电镜超薄切片来观察霍乱弧菌O139在多噬棘阿米巴的滋养体和包囊内生存情况,经包囊传代及低温下生存耐受实验来观察阿米巴包囊能否提高霍乱弧菌O139的环境生存能力。结果与多噬棘阿米巴共培养8 h后,霍乱弧菌O139就能进入阿米巴滋养体内并在空泡内增殖。霍乱弧菌 O139可生存于胞浆空泡内和(或)包囊内壁间,经包囊传代培养能再分离培养出此菌。在30℃时,在棘阿米巴环境下120 d仍能检测出霍乱弧菌O139,而在阿米巴生理盐水液中45 d后就检测不出霍乱弧菌O139。在4℃时,实验组和对照组培养液30 d后均未能培养出霍乱弧菌O139;而被感染包囊分别在30、45、60和75 d后复苏培养能再检测出霍乱弧菌O139;被感染包囊90 d后发育成滋养体能力下降,未能再培养出活的霍乱弧菌O139,在电镜下可见包囊被裂解死亡。结论霍乱弧菌O139能在棘阿米巴的滋养体内繁殖和包囊内生存;阿米巴包囊能够提高霍乱弧菌O139的低温下生存能力;棘阿米巴包囊可能成为霍乱弧菌O139越冬的环境宿主。
Objective To determine whether Acanthamoeba polyphaga could affect the survival and growth of Vibrio cholerae O139 in low temperature. Methods V. cholerae O139 was co-cultured with the Acanthamoeba polyphaga to be examined on its intraeellular growth and survival rate within cysts at low temperature, using methods as Gram-staining, electron microscope and passage culture. Results V. cholerae O139 were observed to enter into the trophozoites and grow the within the vacuoles after 8 hour incubation with Aeanthamoeba polyphaga. The germs survived in the vacuole and/or endo-layer of wall and could be re-isolated from the excystment of Acanthamoeba polyphaga. At 300C , V. cholerae O139 could survive for 120 days with the amoeba while less than 45 days in PAS, At 4℃ , the number of viable bacteria decreased and reached undetectable levels for both study and control groups after a 30-day incubation. V. cholerae O139 could be re-isolated from the 30-, 45-, 60- and 75- day＇s infected cysts after excystment. However the ability of excystment for 90- day＇s infected cysts decreased and V, cholerae O139 within the cyst could not be isolated again because the amoebae had lysed. Conclusion These findings indicated that V. cholerae O139 could grow within Acanthamoeba polyphaga and the survival time could be increased in the cysts at low temperature, It seemed that Acanthamoeba can provide an environmental reservoir for V. cholerae O139.
出处
《中华流行病学杂志》
CAS
CSCD
北大核心
2006年第4期339-342,共4页
Chinese Journal of Epidemiology
