Abstract

Introduction: Infection with Helicobacter pylori(H. pylori) evokes inflammatory and immuneresponses of the host, which most likely determinethe clinical outcome of H. pylori infection.In the gastric epithelium, expression of humanalpha-defensins, beta-defensins (hBD)-1, -2 and-3 has been detected in vivo.In particularly hBD3 as well hBD2 is knownto be induced in gastric epithelial cells infectionby the H. pylori and may be involved inthe pathogenesis of H pylori-associated gastritis,possibly through its function as immuneand inflammatory mediator. However, duringprolonged infection, hBD3 was subsequentlydownregulated by the H. pylori virulence determinantCagA.Materials and Methods: Patients. In this study,serum and biopsies of 33 healthy individualsstratified according to the H. pylori infection(17 positive and 11 negative) was analyzed.Elisa Assay and Real Time PCR. Sera of patientswere assayed by enzyme-linked immunosorbent(ELISA) assay for detection of both hBD-2 (Phoenix Pharmaceuticals, Inc.) and hBD-3(Alpha Diagnostic International) levels, accordingto the manufacture’s protocol. Proteinconcentration was expressed as pg/ml of serumvolume. Real time PCR was carried out withthe LC Fast Start DNA Master SYBR Green kit(LightCycler 2.0 Instrument, Roche; Milano, Italy)and PCR products were examined on 1.4%agarose gel.192 PostersP 136IMPACT OF HBV GENOTYPESA AND D GENETICVARIABILITY ON INFECTIONEVOLUTIONNoemi Urone, Donatella FerraroSezione di Microbiologia “A. Chiarini”, Dipartimento diScienze per la Promozione della Salute e Materno Infantile“G. D’Alessandro”, Università degli Studi di Palermo - ItalyIntroduction: HBV is characterized by a highgenetic variability and several studies havedemonstrated the correlation between viralvariants and severe forms of acute and chronicliver disease. Few data are available about theimpact of genetic variability on the evolution ofacute infection. Recently, 5 SNPs (C504, C801,G1171, T1785 and A1786) into HBV genomewere reported as potential novel markers linkedto a lower rate of chronicity. The aim of thisstudy was to analyze the genetic variability ofHBV genotypes A and D isolates from cases ofself-limiting acute (AHB) and chronic hepatitis(CHB) in order to identify HBV variants associatedwith chronicity or resolution of infection.Patients and Methods: The preS-S, preC-Cand the overlapped P and X genes, were sequencedfrom sera of 33 AHB and 46 CHB Sicilianpatients and analyzed with 92 HBV-A andD sequences from Gene Bank in order to identifyHBV geno/subtype by phylogenetic analysisand to study the genetic variability.Results: Eighteen strains of HBV-D and 15 ofHBV-A from AHB, 42 of HBV-D and 4 of HBVA2from CHB patients were obtained. Two inframe deletions, between preS1 and preS2regions (Δ173-321, Δ1-29) and in the S gene(Δ489-516) were detected in an AHB-D3 strainwhile 2 CHB-D1 strains showed the deletionsΔ37-52 and Δ36-57 into preS2 region. The mutationM01I at preS2 start codon was detectedin 2 AHB-D1 and a CHB-D1strains. Mutationsof immune-escape were not found but >30%of strains showed many amino acid polymorphismsin “a determinant” domain. Secondarydrug resistance mutations on RT-domainswere identifiedGenotyping of H.pylori. The DNA of each biopsy,estracted using a High Pure Template PreparationKit (Roche), was used to amplify followinggenes: ureA, cagA.Results: Protein levels of both studied defensins,hBD-2 and hBD-3, are lower or unchangedin serum of H. pylori- positive compared tothose H. pylori- negative subjects. However,mRNA levels of hBD-2 and hBD-3 are up-regulatedin most gastric bio
Lingua originaleEnglish
pagine (da-a)191-191
Numero di pagine1
RivistaNew Microbiologica
Volume37
Stato di pubblicazionePublished - 2014

    Fingerprint

Cita questo