表达重组猪瘟病毒E290多肽的干酪乳杆菌口服免疫特性及诱导特异性CTL反应的研究

经PCR扩增获得约60bp编码猪瘟病毒T细胞表位E290多肽基因片段,克隆至表达载体pPG-VP2中VP2基因5′端上游,命名为pPG-VP2-E290,电转化干酪乳杆菌,构建了表达猪瘟病毒E290多肽的重组乳酸菌系统。口服免疫BALB/c鼠和新西兰兔,检测诱导小鼠和兔体内产生特异性抗猪瘟病毒E290多肽IgG水平,并对E290多肽的CTL活性进行检测,同时对免疫兔进行猪瘟病毒攻毒实验,检测E290多肽抗体对免疫兔的保护作用。构建的重组猪瘟病毒T细胞表位的干酪乳杆菌具有良好的免疫性,口服免疫后的小鼠和兔血清中均检测到了较高水平的抗E290多肽抗体IgG,且能诱导小鼠机体产生抗猪瘟病毒的特异性CTL反应,亦证实猪瘟病毒E290免疫兔能够抵抗猪瘟病毒的攻击。

The Oral Immune Efficacy of Recombinant Lactobacillus casei Expressing CSFV E290 Peptide and It Elicited Specific CTL Response

The gene encoding classical swine fever virus(CSFV)T cell epitope E290 peptide was synthesized by PCR,cloned into the expression vector pPG-VP2 and named pPG-VP2-E290.The recombinant plasmid was electrotransformed into Lactobacillus casei 393 generating pPG-VP2-E290/L.casei 393.Specific anti-CSFV E290 peptide immunoglobulin G(IgG)antibody was detected by indirect ELISA in the serum of BALB/c mice and rabbits immunized with recombinant strain by oral administration.The CTL of E290 was analyzed with lymphocytes taken from the immunized mice,and the immunized rabbits were attacked with CSFV to validate the protective function of E290 antibody induced.Result:The recombinant expression system constructed with L.casei 393 in this study show a good immunization property and could elicit the mice and rabbits to produce high anti-E290 antibody levels.Furthermore,E290 peptide antibody could elicit specific CTL response,and restrain attack of CSFV to rabbits.