Wullenweber M, Beutin L, Zimmermann S, Jonas C
Central Institute for Laboratory Animal Breeding, Hannover, Germany.
Infect Immun. 1993 May;61(5):2138-44. doi: 10.1128/iai.61.5.2138-2144.1993.
Of 209 healthy infants examined, 44 (21.1%) carried Escherichia coli K1 in their feces. Of these 44 isolates, 36 (81.8%) were attributed to 10 different known clonal groups of E. coli K1 and 4 isolates represented unknown types. The influence of mannose-resistant (MR) adhesins, aerobactin production, and resistance to serum on colonization and invasiveness of E. coli K1 in orally infected inbred LEW baby rats was investigated. Strains expressing MR adhesins had significantly higher colonization and invasion rates than non-MR strains did. Mixed-infection experiments of LEW rats revealed interactions between different types of E. coli K1 strains affecting colonization and invasion rats. P-fimbriated strains appeared to have a selective advantage for colonization. The bacteremic potentials of different E. coli K1 strains could not be associated with their resistance to sera from LEW rats free of members of the family Enterobacteriaceae. No differences in virulence between fecal E. coli K1 isolates and clinical isolates from diseased humans were found. An influence of the major histocompatibility complex on host susceptibility to invasive E. coli K1 was indicated by comparing the parental LEW rat strain with different congenic LEW strains (RT1).
在接受检查的209名健康婴儿中，44名（21.1%）粪便中携带大肠杆菌K1。在这44株分离株中，36株（81.8%）属于10个不同的已知大肠杆菌K1克隆群，4株代表未知类型。研究了甘露糖抗性（MR）黏附素、气杆菌素产生以及对血清的抗性对口服感染近交系LEW幼鼠的大肠杆菌K1在其体内定殖和侵袭的影响。表达MR黏附素的菌株比不表达MR的菌株具有显著更高的定殖和侵袭率。LEW大鼠的混合感染实验揭示了不同类型的大肠杆菌K1菌株之间存在影响大鼠定殖和侵袭的相互作用。P菌毛菌株似乎在定殖方面具有选择性优势。不同大肠杆菌K1菌株的致菌血症潜力与其对不含肠杆菌科成员的LEW大鼠血清的抗性无关。未发现粪便大肠杆菌K1分离株与患病人类临床分离株之间的毒力差异。通过将亲代LEW大鼠品系与不同的同源LEW品系（RT1）进行比较，表明主要组织相容性复合体对宿主对侵袭性大肠杆菌K1的易感性有影响。
