mRNA levels of TLR4 and TLR5 are independent of H pylori.
OBJECTIVE
To determine if the presence H pylori or its virulence affect toll-like receptor 4 (TLR4) and TLR5 mRNA expression levels.


METHODS
For the in vivo assays, gastric biopsies were obtained from 40 patients and H pylori status was determined. For the in vitro assays, human gastric adenocarcinoma mucosal cells (AGS) were cultured in the presence or absence of twelve selected H pylori strains. H pylori strains isolated from culture-positive patients and selected strains were genotyped for cagA and vacA. The cDNA was obtained from mRNA extracted from biopsies and from infected AGS cells. TLR4 and TLR5 mRNA levels were examined by real-time PCR.


RESULTS
The presence of H pylori did not affect the mRNA levels of TLR4 or TLR5 in gastric biopsies. The mRNA levels of both receptors were not influenced by the vacA status (P > 0.05 for both receptors) and there were no differences in TLR4 or TLR5 mRNA levels among the different clinical presentations/histological findings (P > 0.05). In the in vitro assay, the mRNA levels of TLR4 or TLR5 in AGS cells were not influenced by the vacAs1 status or the clinical condition associated with the strains (P > 0.05 for both TLR4 and TLR5).


CONCLUSIONS
The results of this study show that the mRNA levels of TLR4 and TLR5 in gastric cells, both in vivo and in vitro, are independent of H pylori colonization and suggest that vacA may not be a significant player in the first step of innate immune recognition mediated by TLR4 or TLR5.
Garza-González
Elvira
E
Departmento de Microbiologia, Facultad de Medicina, Universidad Autonoma de Nuevo Leon, Av. Madero y Dr. Aguirre s/n, Colonia Mitras Centro, Monterrey 64460, Mexico. elvira_garza_gzz@yahoo.com
Bocanegra-García
Virgilio
V
Bosques-Padilla
Francisco-Javier
FJ
Flores-Gutiérrez
Juan-Pablo
JP
Moreno
Francisco
F
Perez-Perez
Guillermo-Ignacio
GI
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002460:Cell Line; D004847:Epithelial Cells / Q000276:immunology / Q000382:microbiology; D005260:Female; D005753:Gastric Mucosa / Q000276:immunology / Q000382:microbiology; D016481:Helicobacter Infections / Q000235:genetics* / Q000276:immunology*; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D051197:Toll-Like Receptor 4 / Q000235:genetics*; D051198:Toll-Like Receptor 5 / Q000235:genetics*; D014774:Virulence / Q000235:genetics; D055815:Young Adult
D012333:RNA, Messenger; C495345:TLR4 protein, human; C495346:TLR5 protein, human; D051197:Toll-Like Receptor 4; D051198:Toll-Like Receptor 5
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