幽门螺杆菌的形态变异及返祖

Transformation and reversion of Helicobacter pylori in vitro

目的幽门螺杆菌（Ｈｐ）在体外很易发生球形变，目前一般认为是不能培养的退化状态．而对Ｈｐ在环境中生存方式和如何感染大量人群仍不清楚，为此本研究对Ｈｐ的形态变化尤其是球形变的返祖进行了研究．方法本研究通过对１８株Ｈｐ在不同条件下的培养，观察其生存及形态变化，并在加有鸡蛋和小牛血清的空弯培养基上及加有血清有布氏肉汤培养基中是进行培养和返祖，观察其变异规律．结果Ｈｐ可在室温液体中繁殖，１８株中观察到３株球形体Ｈｐ在室温下的返祖，除常见球形变外的Ｈｐ杆状弯曲、长杆状、短杆状、长丝体、巨球体、丝球体、原生质体及细小“Ｓ”和弧形变异．并根据Ｈｐ形态变化的顺序及表型，初步发现Ｈｐ由典型“Ｓ”或多螺旋形态变为杆状弯曲、长杆状、短杆状、然后变为球形、长丝体、巨球体、丝球体、原生质体的规律．部分变异体在一定条件下可返祖．结论Ｈｐ易发生多形变化，有一定规律．可在室温下生长繁殖，球形体可在Ｈｐ鸡蛋培养基上或室温液体培养基中返祖．

AIM Helicobacter pylori (Hp) is subject to transforming from bacterial to coccoid in vitro . The coccoid form of Hp is considered uncultivable and as degenerative status. How does Hp survive in environment and infect so many people are still unknown. METHODS Eighteen Hp strains were cultivated under different conditions to show its transformations. Campylobacter jejuni selected media supplied with egg and calf serum (EHP media) and Brucella broth supplemented with calf serum were used to cultivate Hp for reverting coccoid to bacterial under different conditions. RESULTS Hp can grow in liquid media in room temperature, and 3 out of 18 strains of coccoid Hp reverted to bacterial. Besides coccoid of Hp transformations, curve bacilliform, long bacilliform, short bacilliform, long threadlike, giant coccoid, glomerule, trophoplast, and very small “s” or “c” shaped Hp were found. According to the change sequence and phenotype, the variant rules were revealed that typical S shaped or multi spiral Hp can change to curve or long or short bacilliform, which may then change to coccoid, long threadlike, giant coccoid, trophoplast or glomerule, some of the variants could revert under certain conditions. CONCLUSION Hp can easily transform from one phenotype to another as the variant rule, and can live in room temperature and propagate. Coccoid form of Hp can revert to typical form on EHP media or in liquid in room temperature, suggesting that coccoid Hp may play an important role in Hp infection and relapse.