RESUMEN
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 1.1 x 10(10), 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, 1 micro g 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 8.15 x 10(-8) M to 1.75 x 10(-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.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Productos del Gen pol/antagonistas & inhibidores , ADN Polimerasa Dirigida por ARN/inmunología , Inhibidores de la Transcriptasa Inversa/farmacología , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/genética , Regiones Determinantes de Complementariedad/química , Productos del Gen pol/genética , Productos del Gen pol/inmunología , Vectores Genéticos , Virus de la Hepatitis B/enzimología , Virus de la Hepatitis B/genética , Humanos , Biblioteca de Péptidos , ADN Polimerasa Dirigida por ARN/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/metabolismoRESUMEN
Amyloidosis is a disorder characterized by extracellular deposition of amyloid in various tissues and organs. Gastrointestinal manifestations including gastroparesis, constipation, malabsorption, intestinal pseudo-obstruction, and bleeding are common. GI bleeding is a rare initial symptom which can be fatal in some cases. Absence of systemic symptoms and nonspecific endoscopic findings in amyloidosis may make diagnosis difficult. Therefore, amyloidosis-induced GI bleeding should be considered in patients with an obscure hemorrhage. Recently, we experienced a 65-year-old woman who presented with massive hematochezia as a manifestations of amyloidosis. Colonoscopy and SMA angiography showed massive bleeding in the small and large intestine. Colonoscopic biopsy established amyloidosis. We report this case with a review of the relevant literatures.
Asunto(s)
Amiloidosis/complicaciones , Hemorragia Gastrointestinal/etiología , Enfermedades Intestinales/complicaciones , Anciano , Amiloidosis/diagnóstico , Femenino , Humanos , Enfermedades Intestinales/diagnósticoRESUMEN
BACKGROUND/AIMS: The effective and reproducible diagnostic parameters for differentiating benign from malignant gastrointestinal stromal tumors (GISTs) are still not clear. In this study, GISTs were diagnosed and classified by immunohistochemistry and their clinical and pathologic features were investigated. GISTs were re-evaluated by Amin's and NIH's criteria, and prognostic relevance of these two criteria were compared. METHODS: Fifty cases of gastrointestinal mesenchymal tumor diagnosed from May 1990 to February 2000, were evaluated by immunohistochemical staining for CD117, CD34, smooth muscle actin, and S-100 protein. GISTs were diagnosed according to Amin's and NIH's criteria. The relationship between the prognosis and diagnosis based on Amin's or NIH's classification were analyzed. RESULTS: Thirty cases of gastrointestinal mesenchymal tumors were diagnosed as GISTs. The stomach (40%) and small bowel (40%) were the most common origin for GISTs. Immunophenotypically, null, myoid, neural, combined type were 70.0%, 10.0%, 16.7% and 3.3%, respectively. Seven cases showed metastasis and one case showed recurrence. According to Amin's criteria, 5 benign, 8 borderline and 17 malignant tumors were diagnosed. The NIH's criteria showed 2 very low risk, 6 low risk, 7 intermediate risk, and 15 high risk tumors. Metastasis or recurrence of GISTs had no significant relationship with malignancy according to Amin's criteria (p=0.4069) but had significant correlation with high risk tumor based on NIH's criteria. (p=0.0352). CONCLUSIONS: GISTs showing local invasion, distant metastasis or recurrence were related with high risk tumors based on NIH's criteria. NIH's criteria might be better reliable scheme than Amin's for predicting the prognosis of GISTs.
Asunto(s)
Neoplasias Gastrointestinales/diagnóstico , Tumores del Estroma Gastrointestinal/diagnóstico , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Neoplasias Gastrointestinales/patología , Tumores del Estroma Gastrointestinal/patología , Humanos , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
BACKGROUND/AIMS: Rabeprazole sodium is a potent proton pump inhibitor. We assessed the efficacy, safety and compliance of one-week triple therapy including rabeprazole with amoxicillin and clarithromycin for eradication of Helicobacter pylori (H. pylori). METHODS: Eighty-eight H. pylori-positive patients with peptic ulcer disease were received rabeprazole 10 mg bid, amoxicillin 1,000 mg bid and clarithromycin 500 mg bid for a week. Endoscopic examination with five biopsies (two specimens from the antrum, two from the gastric body, and one from the gastric angle) was performed. The status of H. pylori infection was assessed by histology (immunohistochemistry) of the biopsy specimens, 13C urea breath test, and CLO test at the beginning and 13C urea breath test 4 weeks after the completion of treatment. RESULTS: H. pylori eradication rates were 74.71% by intention-to-treat analysis and 87.84% by per-protocol analysis. The percentage of side effects was 12.5% and these side effects were not serious. CONCLUSIONS: One-week rabeprzole based triple therapy is an effective and safe regimen for H. pylori eradication in patients with peptic ulcer.