McMahon J M, Wells K E, Bamfo J E, Cartwright M A, Wells D J
Department of Neuromuscular Diseases, Imperial College School of Medicine, Charing Cross Hospital, London, UK.
Gene Ther. 1998 Sep;5(9):1283-90. doi: 10.1038/sj.gt.3300718.
Transfer of genes by injection of plasmid DNA into skeletal muscle has a wide variety of applications ranging from treatment of neuromuscular disorders to genetic vaccination. We examined each component involved in the intramuscular injection of plasmid DNA in terms of the induction of inflammatory responses. The insertion of a needle and the injection of a relatively large volume of saline caused very little muscle damage except in rare cases. In contrast, barium chloride-induced regeneration of muscle, injection of lipopolysaccharide, plasmid backbone or plasmid expressing a neo-antigen (beta-galactosidase) all generated widespread inflammation of injected muscle, with mononuclear infiltrate, comprised largely of macrophages and with both CD4+ and CD8+ T lymphocytes, present. Such inflammation may hamper clinical application of this technology and may encourage undesirable immune responses in gene therapy trials. Inflammation was not greatly reduced by CD4- or CD8-depleting antibodies, suggesting this initial inflammation did not involve T cells, but methylation of plasmid DNA before injection substantially lessened the inflammatory response and resulted in longer term expression of the transgene.
通过将质粒 DNA 注射到骨骼肌中来转移基因有着广泛的应用，从治疗神经肌肉疾病到基因疫苗接种。我们从炎症反应的诱导方面检查了质粒 DNA 肌内注射所涉及的每个成分。插入针头以及注射相对大量的盐水除了在极少数情况下外，造成的肌肉损伤非常小。相比之下，氯化钡诱导的肌肉再生、注射脂多糖、质粒骨架或表达新抗原（β-半乳糖苷酶）的质粒都会引发注射肌肉的广泛炎症，出现单核浸润，主要由巨噬细胞以及 CD4+ 和 CD8+ T 淋巴细胞组成。这种炎症可能会阻碍该技术的临床应用，并可能在基因治疗试验中引发不良免疫反应。CD4 或 CD8 耗竭抗体并不能显著减轻炎症，这表明这种初始炎症不涉及 T 细胞，但注射前质粒 DNA 的甲基化可大幅减轻炎症反应，并导致转基因的长期表达。
