title: Tumor necrosis factor-alpha-induced protein 1 and immunity to hepatitis B virus.
abstract: OBJECTIVE
  To compare the gene expression profile in a pair of HBV-infected twins.
  
  
  METHODS
  The gene expression profile was compared in a pair of HBV-infected twins.
  
  
  RESULTS
  The twins displayed different disease outcomes. One acquired natural immunity against HBV, whereas the other became a chronic HBV carrier. Eighty-eight and forty-six genes were found to be up- or down-regulated in their PBMCs, respectively. Tumor necrosis factor-alpha-induced protein 1 (TNF-alphaIP1) that expressed at a higher level in the HBV-immune twins was identified and four pairs of siblings with HBV immunity by RT-PCR. However, upon HBV core antigen stimulation, TNF-alphaIP1 was downregulated in PBMCs from subjects with immunity, whereas it was slightly upregulated in HBV carriers. Bioinformatics analysis revealed a K+ channel tetramerization domain in TNF-alphaIP1 that shares a significant homology with some human, mouse, and C elegan proteins.
  
  
  CONCLUSIONS
  TNF-alphaIP1 may play a role in the innate immunity against HBV.
authors.affiliation: Department of Medicine, Queen Mary Hospital 102 Pokfulum Road, Hong Kong SAR, China.
authors.forename: Marie C
authors.initials: MC
authors.lastname: Lin
authors.forename: Nikki P
authors.initials: NP
authors.lastname: Lee
authors.forename: Ning
authors.initials: N
authors.lastname: Zheng
authors.forename: Pai-Hao
authors.initials: PH
authors.lastname: Yang
authors.forename: Oscar G
authors.initials: OG
authors.lastname: Wong
authors.forename: Hsiang-Fu
authors.initials: HF
authors.lastname: Kung
authors.forename: Chee-Kin
authors.initials: CK
authors.lastname: Hui
authors.forename: John M
authors.initials: JM
authors.lastname: Luk
authors.forename: George Ka-Kit
authors.initials: GK
authors.lastname: Lau
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D004200:Diseases in Twins; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D007113:Immunity, Innate; D053727:Interleukin-18 Receptor alpha Subunit; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics / Q000502:physiology*; D018123:Receptors, Interleukin / Q000235:genetics; D053724:Receptors, Interleukin-18
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C508572:IL18R1 protein, human; C508573:Il18r1 protein, mouse; D053727:Interleukin-18 Receptor alpha Subunit; D011506:Proteins; D018123:Receptors, Interleukin; D053724:Receptors, Interleukin-18; C115968:TNFAIP1 protein, human