title: Antimicrobial peptides in the duodenum at the acute and convalescent stages in patients with diarrhea due to Vibrio cholerae O1 or enterotoxigenic Escherichia coli infection.
abstract: Patients with acute watery diarrhea caused by Vibrio cholerae O1 or enterotoxigenic Escherichia coli (ETEC) were analyzed for innate immune factors produced by the epithelium during the disease process. Duodenal biopsies were obtained from study participants at the acute (day 2) and convalescent (day 21) stages of disease. Levels of α-defensin (HD-5 and -6), β-defensin (hBD-1-4), and cathelicidin (LL-37) mRNAs were determined by real-time qRT-PCR. hBD-2, HD-5, LL-37 peptides were analyzed in duodenal epithelium by immunomorphometry. Concentration of hBD-2 in stool was determined by ELISA. Specimens from healthy controls were also analyzed. hBD-2 mRNA levels were significantly increased at acute stage of diarrhea; hBD-2 peptide was detected in fecal specimens but barely in duodenal epithelium at acute stage. Immunomorphometry analysis showed that Paneth cells contain significantly higher amounts of HD-5 pre/propeptide at convalescence (P<0.01) and in healthy controls (P<0.001) compared to acute stage, LL-37 peptide levels also decreased at acute stage while mRNA levels remained unchanged. mRNA expression levels of the other antimicrobial peptides remained unchanged with higher levels of α-defensins than β-defensins. V. cholerae induced an innate immune response at the acute stage of disease characterized by increased expression of hBD-2, and continued expression of hBD-1, HD-5-6, and LL-37.
authors.affiliation: International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh.
authors.forename: Tahmina
authors.initials: T
authors.lastname: Shirin
authors.forename: Arman
authors.initials: A
authors.lastname: Rahman
authors.forename: Åke
authors.initials: Å
authors.lastname: Danielsson
authors.forename: Taher
authors.initials: T
authors.lastname: Uddin
authors.forename: Taufiqur Rahman
authors.initials: TR
authors.lastname: Bhuyian
authors.forename: Alaullah
authors.initials: A
authors.lastname: Sheikh
authors.forename: Syed Saleheen
authors.initials: SS
authors.lastname: Qadri
authors.forename: Firdausi
authors.initials: F
authors.lastname: Qadri
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Hammarström
mesh_terms: D000328:Adult; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000032:analysis* / Q000235:genetics; D002771:Cholera / Q000378:metabolism* / Q000382:microbiology; D003289:Convalescence; D003967:Diarrhea / Q000378:metabolism* / Q000382:microbiology; D004386:Duodenum / Q000378:metabolism; D054307:Enterotoxigenic Escherichia coli / Q000302:isolation & purification / Q000502:physiology*; D004927:Escherichia coli Infections / Q000378:metabolism* / Q000382:microbiology; D005260:Female; D006041:Goats; D006736:Horses; D006801:Humans; D008297:Male; D051379:Mice; D008875:Middle Aged; D009113:Muramidase / Q000235:genetics / Q000378:metabolism; D012329:RNA, Bacterial / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D041241:Vibrio cholerae O1 / Q000302:isolation & purification / Q000502:physiology*; D055815:Young Adult
chemical_list: D023181:Antimicrobial Cationic Peptides; D012329:RNA, Bacterial; D012337:RNA, Ribosomal, 18S; D009113:Muramidase