Characterization of flgK gene and FlgK protein required for H pylori Colonization-from cloning to clinical relevance

Table 1 H pylori gastric colonization and the corresponding serologic responses to FlaA and r-FlgK of H pylori in different mouse groups

Mean (SD)	W group	M group	I group
1-wk mouse groups	(n = 15)	(n = 15)	(n =15)
Anti-FlaA (A)	0.312 (0.141)	0.301 (0.115)	0.289 (0.128)
Anti-r-FlgK (A)abc	0.459 (0.066)	0.329 (0.085)	1.258 (0.692)
HPD (0-15)ac	5.35 (2.08)	3.65 (2.87)	5.24 (2.15)
4-week mouse groups	(n = 13)	(n = 14)	(n = 14)
Anti-FlaA (A)	0.345 (0.105)	0.324 (0.115)	0.298 (0.101)
Anti-r-FlgK (A)abc	0.682 (0.395)1	0.351 (0.052)	1.325 (0.171)
HPD (0-15)ab	6.59 (2.78)1	4.25 (2.15)	3.89 (1.85)1

W group: mice challenged with wild-type H pylori; M group: mice challenged with isogenic flgK-mutant; I group: mice received pre-immunization of r-FlgK before challenge of wild-type H pylori; HPD: total H pylori density of the mice's stomachs by histology. The value of anti-FlaA and anti-r-FlgK was indicated as optical density (A) checked by ELISA with a 1:1000 dilution of serum.

^aindicated significant difference between W and M mice groups;

^bbetween W and I mice groups;

^cbetween I and M mice groups (One way ANOVA test with Bonferroni’s method, P < 0.05);

¹ indicated significant difference of this parameter between the 1-wk and the 4-wk samples within the same mouse group (Student’s t test, P < 0.05).

Table 2 The serologic responses against FlaA and r-FlgK of H pylori among patients with different gastric colonization

Serological A titer	H pylori–negative	Low colonization	High colonization
Mean (SD)	(n = 20)	(n = 20)	(n = 30)
Anti-FlaAab	0.268 (0.152)	0.298 (0.118)	0.398 (0.159)
Anti-r-FlgK	0.468 (0.154)	0.501 (0.258)	0.521 (0.233)

Low colonization and high colonization were defined by the total H pylori density in the human stomach scored as less or equal to 5 and more than 5, respectively. A: indicates the optical density of titer checked by ELISA with a 1:1000 dilution of serum.

^aindicated significant difference between patients without H pylori infection and with high colonization;

^bindicated significant difference between patients with low and with high colonization (One way ANOVA test with Bonferroni’s method, P < 0.05).