Résumé
<p><b>OBJECTIVE</b>To construct chimerical DNA vaccine plasmid of human papillomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity.</p><p><b>METHODS</b>Molecular cloning techniques were used to construct recombinant plasmid pcDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection.IL-2 and gamma-INF secreted by immunized spleens lymphocyte and HPV 11 L1 or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay.</p><p><b>RESULTS</b>The chimerical DNA plasmid of pcDNA3 L1-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and gamma-INF were detected in vaccinated mice.</p><p><b>CONCLUSION</b>Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.</p>
Sujets)
Animaux , Femelle , Humains , Souris , Anticorps antiviraux , Sang , Allergie et immunologie , Séquence nucléotidique , Génie génétique , Papillomavirus humain de type 11 , Génétique , Allergie et immunologie , Souris de lignée BALB C , Données de séquences moléculaires , Infections à papillomavirus , Sang , Allergie et immunologie , Virologie , Vaccins contre les papillomavirus , Génétique , Allergie et immunologie , Répartition aléatoire , Vaccins à ADN , Génétique , Allergie et immunologieRésumé
Objective To evaluate the possibility of methylation analysis of secreted frizzled-related protein gene 2 (SFRP2),hyperplastic polyposis protein gene (HPP1) and O~6-methylguanine-DNA methyhransferase gene (MGMT) in feces for screening colorectal cancer (CRC).Methods Total DNA was isolated from fecal samples of 52 patients with colorectal cancer and 35 patients with benign colorectal diseases and 24 normal volunteers,and the methylation status of SFRP2,HPP1 and MGMT was analyzed with methylation-specific polymerase chain reaction.Results SFRP2,HPP1 and MGMT were methylated in 94.2%,71.2%,48.1% of CRCs,respectively.At least one of the three genes was methylated in 96.2% of CRCs and 81.8% of precancerous lesions,respectively.In contrast,of the 24 normal controls,only one had methylated SFRP2.These results indicated 93.7% sensitivity,77.1% specificity,84.3% positive predicative value and 90.2% negative predictive value of the test for detecting CRC and precancerous lesions.Conclusions Methylation analysis of SFRP2,HPP1 and MGMT gene in stool is a high sensitive screening tool for CRC and precancerous lesions.Analysis of fecal DNA methylation is expected to serve as a new detection way for CRC or a new screening tool for individuals at risk of developing colorectal neoplasm.