Improved Immunogenicity of DNA Constructs Co-expressing the GP5 and M Proteins of Porcine Reproductive and Respiratory Syndrome Virus by Glycine-proline-glycine-proline (GPGP) Linker in Mice

以GPGP連接子改進表現豬生殖與呼吸道綜合症病毒GP5和M蛋白之DNA疫苗於小鼠的免疫原性

賈敏原(Min-Yuan Chia) ； 蕭世烜(Shih-Hsuan Hsiao) ； 詹惠婷(Hui-Ting Chan) ； 杜宜殷(Yi-Yin Do) ； 黃鵬林(Pung-Ling Huang) ； 張惠雯(Hui-Wen Chang) ； 蔡依潔(Yi-Chieh Tsai) ； 林俊明(Chun-Ming Lin) ； 鄭穹翔(Chiung-Hsiang Cheng) ； 龐飛(Victor Fei Pang) ； 鄭謙仁(Chian-Ren Jeng)

《臺灣獸醫學雜誌》 37卷1期 (2011/03) Pp. 12-23

https://doi.org/10.7009/TVJ.201103.0012

摘要

本研究的目的是評估以glycine-proline-glycine-proline (GPGP)作為連接子，同時表現豬生殖與呼吸道綜合症病毒(PRRSV)的封套醣蛋白(GP5)和膜蛋白(M)之DNA疫苗免疫小鼠時，是否能促進小鼠的免疫反應，共設計三組不同的DNA構築；分別為(1)不具GPGP連接子的pcDNA-56；(2)具有GPGP連接子的pcDNA-5L6；(3)具有GPGP連接子的pcDNA-6L5。將上述三組構築載入真核表現系統之載體(pcDNA3.1/V5-His TOPO)內，作為DNA疫苗使用，再將此三組疫苗以肌肉注射的方式免疫小鼠四次，每次間隔兩週，藉以評估其誘發之免疫反應，於實驗期間收集小鼠之血清作為PRRSV特異性抗體檢測之用，並於小鼠犧牲時收集其脾臟細胞作為淋巴細胞增殖反應檢測之用。結果顯示小鼠免疫pcDNA-5L6或pcDNA-6L5組所誘發的PRRSV特異性血清IgG抗體、中和抗體、和淋巴細胞增殖反應都比pcDNA-56組為佳。此結果證實以GPGP連接子同時表現GP5和M蛋白時，具有還原GP5/M蛋白自然結構的功能，進而促進該蛋白對小鼠的免疫原性。

關鍵字

封套醣GP5和膜M蛋白 ； GPGP連接子 ； 豬生殖與呼吸道綜合症病毒 ； 小鼠

並列摘要

The objective of the study was to evaluate whether co-expressing porcine reproductive and respiratory syndrome virus (PRRSV) envelop glycoprotein 5 (GP5) and matrix (M) protein linked by glycine-proline-glycine-proline (GPGP) could enhance its immunogenicity in mice. Three DNA constructs expressing GP5/M without GPGP linker (pcDNA-56), GP5/M conjugated by GPGP linker (pcDNA-5L6), and M/GP5 conjugated by GPGP linker (pcDNA-6L5) were included. These constructs were then inserted into an eukaryotic expression vector, pcDNA3.1/V5-His TOPO, as DNA vaccines to inject mice intramuscularly for four times at a 2-week interval. Serum samples were collected at various designated time points for the measurement of PRRSV-specific antibodies and splenocytes were isolated at time of sacrifice for lymphocyte blastogenesis assay. The results showed that pcDNA-5L6- and pcDNA-6L5-inoculated mice displayed higher PRRSV-specific neutralizing antibody (NA) titers, serum IgG responses, and lymphocyte proliferative responses than did the pcDNA-56-inoculated mice. The data indicated that co-expressing GP5/M with GPGP can indeed improve the immunogenicity of the heterodimeric complex.

並列關鍵字

GP5 and M proteins ； GPGP linker ； mice ； PARSV