Glycosylation of recombinant human thyroid peroxidase ectodomain of insect cell origin has little effect on recognition by serum thyroid peroxidase antibody / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Thyroid peroxidase (TPO) is an important autoantigen in Hashimoto's thyroiditis (HT), and almost all epitopes are located in TPO ectodomain. The glycosylation of TPO might contribute to breaking self-tolerance, therefore, purified glycosylated recombinant TPO ectodomain is prerequisite of elucidating its role in the pathogenesis of HT. The aim of our study was to investigate whether the glycosylation has influence on the antigenic determinants of recombinant TPO.</p><p><b>METHODS</b>Bac-to-Bac baculovirus expression system was used to generate recombinant human TPO ectodomain. The antigenicity was analyzed by antigen specific enzyme-linked immunosorbant assays (ELISAs). The glycosylation of recombinant human TPO ectodomain of High Five insect cell origin was detected by lectin-ELISAs.</p><p><b>RESULTS</b>TPO ectodomain was recovered from the culture media as a soluble protein, and it was fused with a hexahistidine tag which allowed purification by nickel-affinity chromatography. The recombinant TPO ectodomain could be recognized by all the 54 HT patients and three TPO monoclonal antibodies. Fucose, sialic acid and galactose were all detected on the recombinant TPO ectodomain. Sera TPOAb binding decreased slightly after non-specific deglycosylation of TPO by periodic acid.</p><p><b>CONCLUSIONS</b>High Five insect cells derived recombinant human TPO ectodomain had N-glycosylation sites, which might have little effect on recognition by serum TPOAb.</p>

Relative Analysis between Drug Sensitivity and Escherichia Coli Induced Enzymes in Childhood Diarrhea / 实用儿科临床杂志

Objective To investigate the distribution of pathogenic bacteria,drug sensitivity,and the relationship between drug sensitivity and Escherichia coli(E.coli) induced enzymes in childhood diarrhea in the last 2 years in Chongqing area,so as to provide important evidence for pediatric clinical therapy.Methods Thirty-one E.coli induced enzymes,extended spectrum ?-laetamases(ESBLs),cephalosporinase(AmpC)detected in different phenotype methods,and drug sensitivity was measured in paper strip method,and the specimens were collected from children′s hospital affiliated to chongqing university of medical sciences from Jan.2005 to Dec.2006 were determined.Among the total,there were 18 enteropathogeic E.coli(EPEC) strains,8 enterotoxigenic E.coli(ETEC) strains and 5 enteroinvasive E.coli(EIEC) strains.In addition,drug resistance tests by paper strip included chloramphenicol(CHL),amikacin(AMK),gentamicin(GEN),norfloxacin(NOF),ciproflocacin(CIP),cefazolin(CEZ),cefoperazone(CPZ),ceftriaxone(CRO),ceftazidime(CAZ),cefotacime(CTX),cefepime(FEP),imipenem(IPM).SPSS 12.0 software was used to analyze the data.Results Three point two percent of the 31 E.coli were drug resistant to IPM,and 35.5%,38.7% to NOF,CIP individually,but more than 60% to AMK,GEN,even more than 67.7% towards cephalosporin(except ceftazidime and cefepime);the gross enzyme-produced rate was 87.1%,rate of single ESBLs,AmpC,and induction of both enzymes simultaneously presented 64.5%,6.5%,16.1% respectively;and there was marked difference in drug resistance when bacteria that produced single AmpC versus bacteria that produced single ESBLs or that produced both ESBLs and AmpC(Pa﹤0.05).Conclusions The relationships among enzyme′s quantity,sort and bacterial resistance are different.These data show E.coli infected by bacterial diarrhea children in Chongqing due to a high rate of induced enzymes,and their drug resistance vary according to the state of induced enzymes.