Gómez Evangelina, Chimeno Zoth Silvina, Carrillo Elisa, Estela Roux María, Berinstein Analía
Instituto de Biotecnología, CICVyA, INTA, Cc25 B1712WAA Castelar, Buenos Aires, Argentina.
Immunobiology. 2008;213(8):671-5. doi: 10.1016/j.imbio.2008.02.002. Epub 2008 Apr 2.
Oral immunization is an efficient means to induce protection at the portal entrance for many pathogens. Therefore, the design of efficient edible vaccines through transgenic plants represents a challenging alternative to the traditional injectable ones. We have previously reported the construction of transgenic potato plants expressing the genes coding for the immunogenic proteins of Newcastle Disease Virus (NDV) and their immunogenicity in mice. All mice receiving transgenic plant extracts in incomplete Freund's adjuvant produced specific antibodies. Animals fed with transgenic leaves also showed a specific response against NDV. The aim of the present study was to continue the evaluation of the mucosal immune response. Adult Balb/c mice were fed with potato leaves for a month and on day 36 mucosal samples were collected. ELISAs performed on intestinal washes showed that transformed plants elicited the synthesis of NDV-specific IgG and IgA antibodies. In addition, anti-NDV IgA antibodies were detected in supernatants of cultured small intestine fragments of mice fed with the recombinant immunogens, suggesting the presence of NDV-specific IgA secreting plasma cells in the intestinal tissue. Moreover, we detected specific anti-NDV antibodies in intestinal fluids after oral immunization with F and HN transgenic plants. Also, indirect immunofluorescence on intestinal tissue was performed. The present results suggest that these immunogens, F and HN glycoproteins of NDV, when orally administered, would enhance the number of IgA(+) B cells, and the cytotoxic cellular immune response via CD8(+) T cells, found in the gut lamina propria that is in accordance with our first findings.
口服免疫是在许多病原体的门户入口诱导保护性免疫的有效手段。因此，通过转基因植物设计高效的可食用疫苗是传统注射疫苗的一种具有挑战性的替代方法。我们之前报道了表达新城疫病毒（NDV）免疫原性蛋白基因的转基因马铃薯植株的构建及其在小鼠中的免疫原性。所有在不完全弗氏佐剂中接受转基因植物提取物的小鼠都产生了特异性抗体。喂食转基因叶片的动物也显示出对NDV的特异性反应。本研究的目的是继续评估黏膜免疫反应。将成年Balb/c小鼠喂食马铃薯叶片一个月，并在第36天收集黏膜样本。对肠道冲洗液进行的酶联免疫吸附测定（ELISA）表明，转基因植物引发了NDV特异性IgG和IgA抗体的合成。此外，在用重组免疫原喂食的小鼠的培养小肠片段的上清液中检测到了抗NDV IgA抗体，这表明肠道组织中存在分泌NDV特异性IgA的浆细胞。此外，在用F和HN转基因植物口服免疫后，我们在肠液中检测到了特异性抗NDV抗体。同时，对肠道组织进行了间接免疫荧光检测。目前的结果表明，这些免疫原，即NDV的F和HN糖蛋白，经口服给药后，会增加固有层中IgA(+) B细胞的数量，并通过CD8(+) T细胞增强细胞毒性细胞免疫反应，这与我们最初的发现一致。
