The effect of the repeated subcultures of Helicobacter pylori on adhesion, motility, cytotoxicity, and gastric inflammation.
In vitro subcultures of bacteria can lead to genetic and phenotypic changes. This study aimed at investigating the effect of repeated subcultures on the adhesion, motility, cytotoxicity, and gastric inflammation caused by Helicobacter pylori. H.pylori SS1 strain was subcultured 64 times on agar plates containing Brucella broth and 5% bovine calf serum. The adhesion, motility, cytotoxicity, and gastric inflammation produced in Mongolian gerbils were compared between the first and 64th subcultured strain. The adhesion rates, following 3 hr exposure of AGS cells to either the first strain or the 64th-transferred strain, were 21% and 12%, respectively. The motility of the 64th-transferred strain decreased significantly when compared to the 1st strain (9.1 mm vs. 15.1 mm). The cytotoxicity index tended to be higher in the first strain than in the 64th-transferred strain (73.7% vs. 69.2%). The initial infection rate on the gerbils showed no difference between the two strains. However, chronic gastric inflammation of the first strain-infected gerbils was somewhat more severe than that of the 64th-transferred strain-infected gerbils. Therefore, the use of repeatedly subcultured strains of H. pylori in virulence experiments can lead to different results from those of the original strain.
Kim
Sung Soo
SS
Division of Gastroenterology, Department of Internal Medicine, College of Medicine, Catholic University of Korea, Seoul, Korea.
Lee
Hak Sung
HS
Cho
Young Seok
YS
Lee
Youn Soo
YS
Bhang
Choon Sang
CS
Chae
Hiun Suk
HS
Han
Sok Won
SW
Chung
In Sik
IS
Park
Doo Ho
DH
D000818:Animals; D001422:Bacterial Adhesion; D005756:Gastritis / Q000276:immunology / Q000382:microbiology*; D005849:Gerbillinae; D016481:Helicobacter Infections / Q000276:immunology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000254:growth & development / Q000472:pathogenicity*; D008297:Male; D014774:Virulence