高效电融合法制备抗牛γ-干扰素单克隆抗体

目的为了获得高特异性牛γ-干扰素单克隆抗体。方法采用工程菌BL21(DE3)/p ET28aHis-BoIFN-γ表达的目的蛋白BoIFN-γ免疫小鼠,优化电融合条件,制备抗BoIFN-γ单克隆抗体,采用间接酶联免疫吸附法、蛋白质印迹法鉴定单克隆抗体特异性。结果在裂解大肠杆菌液的上清液中目的蛋白BoIFN-γ高表达。脾脏淋巴结细胞与SP2/0细胞比例3∶1,单次融合细胞数3×10;个,交变电场电压40 V,直流脉冲电压500 V时,细胞融合率可达0.41%。而PEG法的细胞融合率为0.07%。获得3株抗BoIFN-γ单克隆抗体杂交瘤细胞株(2E9、3F7、5B7),2E9和5B7的亚类为IgG2a,3F7亚类为IgG2b。抗体最高效价为1∶25600,3株单抗均可识别标准BoIFN-γ蛋白,其中3F7亲和力最高。结论说明细胞高效电融合法的细胞融合率显著高于PEG化学诱导法。电融合法制备的单克隆抗体效价高、特异性强、敏感度高。

Sequencing and Analysis of a 1500 bp HindIII KpnI Fragment from LsNPV

A 1500 bp DNA fragment of LsNPV genome was sequenced by silver sequencing system.A whole coding region of ORF1 and an incomplete ORF2 were found.ORF1 was 345 bp long and was predicted to encode a protein with 115 amino acid residues,the 5'regulatory region of ORF1 contained early transcriptional consensus sequence such as AT/ACGTGT,CGTGC and a stem loop structure.On the 3'terminus of ORF1,a poly(A)tail signal was found.Incomplete ORF2 was 354 bp long and predicted to encode 118 amino acid residues,the 5'regulatory region of ORF2 contained two conserved late transcriptional motif ATAAG.Compared with all the genes from AcNPV,incomplete ORF2 showed 56.5%nucleotide sequence homology and 44.9%amino acid sequence homology with AcNPV PDV E66 gene.Two conserved ATAAG motif on 5'regulatory region of ORF2 was similar to those in AcNPV PDV E66 gene.ORF1 showed no high identity with AcNPV and other baculoviruses.

胃上皮内瘤变术前活检与内镜黏膜下剥离术后病理差异性的探讨

目的对胃黏膜上皮内瘤变术前活检与内镜黏膜下剥离术(ESD)后出现病理差异这一现象进行探讨,并分析导致这种差异的原因以及相关影响因素。方法回顾性分析了2016年7月至2019年6月经江苏省中医院住院行ESD治疗、术前活检为低级别上皮内瘤变(LGIN)/高级别上皮内瘤变(HGIN)的342例患者资料,运用统计学方法分析导致差异的影响因素。结果 342例患者中,187例为LGIN、155例为HGIN。LGIN组中病理一致者占61. 5%,升级为HGIN、早期胃癌及以上者分别为21. 4%、12. 8%,总升级率34. 2%,降级为慢性炎症者4. 3%。HGIN组病理维持一致者占40. 6%,升级为早期胃癌及以上者占52. 9%,降级为LGIN者6. 5%。多因素回归分析结果显示:病灶位于胃上1/3、表面充血、结节、放大内镜下DL(+)、MV(+)是LGIN组病理升级的危险因素;病灶表面结节是HGIN病理升级的危险因素。结论白光内镜下活检与ESD后病理存在差异,病灶在胃上1/3、表面充血、结节、DL(+)、MV(+)是LGIN病理升级的危险因素;病灶表面结节是HGIN病理升级的危险因素。