Hallengärd David, Haller B Kristian, Maltais Anna-Karin, Gelius Eva, Nihlmark Kopek, Wahren Britta, Bråve Andreas
Swedish Institute for Communicable Disease Control, Nobels Väg 18, 171 82 Solna, Stockholm, Sweden.
Clin Vaccine Immunol. 2011 Sep;18(9):1577-81. doi: 10.1128/CVI.05045-11. Epub 2011 Jul 13.
In vivo electroporation (EP) has proven to significantly increase plasmid transfection efficiency and to augment immune responses after immunization with plasmids. In this study, we attempted to establish an immunization protocol using intradermal (i.d.) EP. BALB/c mice were immunized with a plasmid encoding HIV-1 p37Gag, either i.d. with the Derma Vax EP device, intramuscularly (i.m.) without EP, or with combinations of both. A novel FluoroSpot assay was used to evaluate the vaccine-specific cellular immune responses. The study showed that i.d. EP immunizations induced stronger immune responses than i.m. immunizations using a larger amount of DNA and that repeated i.d. EP immunizations induced stronger immune responses than i.m. priming followed by i.d. EP boosting. Two and three i.d. EP immunizations induced immune responses of similar magnitude, and a short interval between immunizations was superior to a longer interval in terms of the magnitude of cellular immune responses. The FluoroSpot assay allowed for the quantification of vaccine-specific cells secreting either gamma interferon (IFN-γ), interleukin-2 (IL-2), or both, and the sensitivity of the assay was confirmed with IFN-γ and IL-2 enzyme-linked immunosorbent spot (ELISpot) assays. The data obtained in this study can aid in the design of vaccine protocols using i.d. EP, and the results emphasize the advantages of the FluoroSpot assay over traditional ELISpot assay and intracellular staining for the detection and quantification of bifunctional vaccine-specific immune responses.
体内电穿孔（EP）已被证明可显著提高质粒转染效率，并增强质粒免疫后的免疫反应。在本研究中，我们试图建立一种使用皮内（i.d.）电穿孔的免疫方案。用编码HIV-1 p37Gag的质粒对BALB/c小鼠进行免疫，分别采用Derma Vax EP装置进行皮内免疫、不进行电穿孔的肌肉内（i.m.）免疫或两者结合的方式。使用一种新型的FluoroSpot检测法来评估疫苗特异性细胞免疫反应。研究表明，皮内电穿孔免疫诱导的免疫反应比使用大量DNA的肌肉内免疫更强，并且重复皮内电穿孔免疫诱导的免疫反应比肌肉内初免后再进行皮内电穿孔加强免疫更强。两次和三次皮内电穿孔免疫诱导的免疫反应强度相似，就细胞免疫反应强度而言，免疫间隔短优于间隔长。FluoroSpot检测法可对分泌γ干扰素（IFN-γ）、白细胞介素-2（IL-2）或两者的疫苗特异性细胞进行定量，并且通过IFN-γ和IL-2酶联免疫吸附斑点（ELISpot）检测法证实了该检测法的敏感性。本研究获得的数据有助于设计使用皮内电穿孔的疫苗方案，结果强调了FluoroSpot检测法相对于传统ELISpot检测法和细胞内染色在检测和定量双功能疫苗特异性免疫反应方面的优势。
