Human Monoclonal Antibody Inhibiting Reverse Transcriptase Activity of Hepatitis B Virus Polymerase Protein / 대한소화기학회지

BACKGROUND/AIMS: To develop a novel treatment method for hepatitis B virus (HBV) infection, we aimed to make a human monoclonal antibody inhibiting reverse transcriptase (RT) activity of P protein which was important in HBV replication by using phage display technique. Therefore, we analysed the usability of human monoclonal antibody as a protein based gene therapy. METHODS: Reverse transcriptase/polymerase (RT/POL) functional motif of P protein of HBV was cloned in pMAL-c vector and expressed as maltose binding fusion protein form. The RT/POL recombinant protein (pMRT/POL) was purified by amylose resin column. Using human single chain Fv phage antibody library with 1.1x10(10) size, human antibody against pMRT/POL was selected with BIAcore panning. Selected antibody fragments were analyzed for the activity of RT inhibition. Finally, they were analyzed for the affinity with BIAcore and the complementarity determining regions with nucleotide sequencing. RESULTS: pMRT/POL recombinant protein expressed in E. coli showed RT activity, 1microgram of recombinant protein had an activity equivalent to 5 unit of MMLV RT. By BIAcore panning, we could select 3 clones; POL-A5, POL-B8 and POL-B12. Each clone's RT inhibiting activity were 52-82%, affinity against antigen were 8.15x10(-8) M to 1.75x10(-6) M. CONCLUSIONS: Human monoclonal antibodies produced in this study showed low affinity, but efficiently inhibited the activity of RT in vitro. If POL-A5, POL-B8, and POL-B12 can be converted to intracellular antibody form, it can be used for protein-based gene therapy by inhibiting the replication through the neutralization of polymerase protein of HBV.

In Vitro IL-1, TNF and IL-6 Production of Peripheral Blood Mononuclear Cells Stimulated with Different Hemodiaysis Membranes / 대한내과학회지

OBJECTIVES: In order to evaluate the role of these cytokines in biological response induced by blood interaction with hemodialysis membranes. METHODS: We have investigated the IL-1, TNF and IL-6 concentrations in the supernatant of 24-hours cultured peripheral blood mononuclear cells (PBMC) without(spontaneous group) or with broken cuprophan or P1VMA membranes in 9 chronic hemodialyzed patients and 8 healthy controls. The blood samples were drawn before dialysis using following criteria: (a) in last dialytic treatment with PMMA membranes(HDEl), (b) after two weeks of dialytic treatment wih cuprophan membranes(HDE2). RESULTS: In the both of patient group(HDE1 and HDE2) and controls production of IL-l, TNF and IL-6 of PBMC stimulated with cuprophan or PMMA membrane particles was increased compared to those of spontaneous group. IL-1 production of HDE1 stimulated PMMA(99.31 +/- 30.15fmol/ml) was significantly higher compared to that of cuprophan(48.43 +/- 11.29fmol/ml), TNF production of HDE2 with cuprophan(114.86 +/- 38.5lfmoVml) was significantly high compared to that of spontaneous group(52.42 +/- 29.94fmol/ml). IL-6 production of HDE2(646.70 +/- 103.84fmol/ml) was significantly high compared to that of spontaneous group(385.88 +/- 87.03fmoVml). Comparing cytokine production of PBMC, there was a significant correlation between IL-1 and IL-6(r=0.78), IL-1 and TNF(r=0.78) and TNF and IL-6(r=0,76). CONCLUSION: Our results show that the interaction of cuprophan or PMMA membranes with blood increase the production of IL-1, TNF and IL-6. We suggest that in patients undergoing routine hemodialysis PBMC are primed by exposure to chronic stimulation.

Four Cases of Brunner's Gland Adenoma / 대한소화기내시경학회지

Brunners gland adenoma is a benign epithelial tumor of the duodenum originating from submucosal Brunners gland. This is an extremely rare entity that account for only 10.6% of benign duodenal tumor, which are themselves relatively rare, representing 0.008% of all surgical and autopsy specimens. The clinical manifestation are nonspecific gastrointestinal complaints, such as bloating or epigastric pain, and the tumor gives rise to melena or anemia, due to the ulceration or erosion of the tumor. The diagnosis is usually made by radiologic studies and gastroduodenal endoscopy which can also provide definitive treatment. The aim of treatment is complete removal of the lesion and exclude malignancy. We report on 4 cases of Brunners gland adenoma which was confirmed by operation or endoscopic polypectomy.