To establish Helicobacter hepaticus infected models in different mice strains and to analyze pathological characteristics / 中华消化杂志

ABSTRACT

ObjectiveTo obtain stable animal models and observe Helicobacter hepaticas (Hh)colonization and pathological claracteristics,through infecting different mice strains with Hh.Methods SPF-class male BABL/c Cr,SCID/Cr and C57BL/6 Cr mice were inoculated 0.2 ml Hh standard strain ATCC51450 bacterial suspension (1 × 108CUF/ml),inoculated for 3 times with 48 hours intervals,the control group was fed with the same volume of PBS.Mice were executed at 4 weeks,8weeks and 16 weeks since last Hh inoculation,and mice esophagus,stomach,jejunum,ileum,cecum,colon,liver and pancreas tissue were taken for histopathology examination,Micro-aerobic bacteria isolation,culture and identification and Hh specific 16S rRNA gene amplification.Results The colonization rates of Hh in cecum after inoculated in BALB/c Cr mice and SCID/Cr mice at 4 weeks,8 weeks and 16 weeks were all 8/8,colonization rates in colon at 4 weeks,8 weeks and 16 weeks were 4/8,5/8,5/8 and 3/8,6/8,5/8 respectively,colonization rates in ileum and jejunum at 16 weeks were 1/8,colonization rates in liver at 8 weeks and 16 weeks were 2/8,3/8 and 2/8,2/8respectively.The colonization rates of Hh in cecum after inoculated in C57BL/6 Cr mice at 4 weeks,8weeks and 16 weeks were 1/8,2/8 and 2/8 respectively,colonization rates in colon at 8 weeks and 16weeks were 1/8,2/8 respectively.Compared with C57BL/6 Cr mice,the inflammatory changes in liver,cecum and colon were more significant in Hh infected BALB/c Cr and SCID/Cr mice (P＜0.01),and histological scores gradually increased as infection time extended (P＜0.05,P＜ 0.01 ).The histological scores were significantly higher in those with colon and liver Hh bacterial colonization than those without Hh bacterial colonization (P＜0.05).The histopathological score of cecal tissue was positively correlated with the density of Hh colonization.ConclusionDifferent mice strains are with different susceptibility to Hh,and better Hh infection model can be obtained in Hh inoculated BALB/c Cr and SCID/Cr mice.