Scheiblhofer Sandra, Stoecklinger Angelika, Gruber Christina, Hauser-Kronberger Cornelia, Alinger Beate, Hammerl Peter, Thalhamer Josef, Weiss Richard
Christian Doppler Laboratory for Allergy Diagnosis and Therapy, Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria.
Mol Immunol. 2007 Mar;44(8):1879-87. doi: 10.1016/j.molimm.2006.09.023. Epub 2006 Oct 30.
Gene gun immunization has been associated with the induction of a heterologous type of immune response characterized by a T(H)1-like immune reaction on the cellular level, i.e. generation of IFN-gamma secreting CD8(+) T-cells, yet a T(H)2 biased serology as indicated by high IgG1:IgG2a ratios and induction of IgE. Nevertheless, gene gun immunization using the model molecule beta-galactosidase has been argued to prevent IgE induction and to promote T(H)1 cells with respect to allergy DNA immunization. In our current study, we evaluated the potential of gene gun immunization to prevent type I allergic reactions comparing beta-galactosidase with two clinically relevant allergens, and further investigated the effect of gene gun immunization on relevant lung parameters. BALB/c mice were immunized with plasmids encoding the birch pollen allergen Bet v 1, the grass pollen allergen Phl p 5, or the model molecule beta-galactosidase, either by gene gun or intradermal injection followed by sensitization and intranasal provocation with the respective allergen. IgG1 and IgG2a antibody titers were determined by ELISA. IgE levels were evaluated in a rat basophil release assay. The severity of eosinophilia was determined in bronchoalveolar lavages, and the overall infiltrate was analyzed by histology on lung paraffin sections. Gene gun immunization induced a T(H)2-biased immune reaction, which did not prevent from production of IgE after subsequent sensitization. This T(H)2 effect was influenced by the nature of the antigen, with a more pronounced T(H)2-bias for the allergens Bet v 1 and Phl p 5 compared to beta-galactosidase. Gene gun immunization with all three antigens promoted eosinophil influx into the lung and did not alleviate lung pathology after intranasal provocation. In contrast to needle injection of plasmid DNA, which triggers a clearly T(H)1-biased and allergy-preventing immune response, gene gun application fails to induce anti-allergic reactions with all tested antigens and is therefore contraindicated for allergen-specific immunotherapy.
基因枪免疫与一种异源类型的免疫反应诱导有关，其特征是在细胞水平上呈现类似T(H)1的免疫反应，即产生分泌IFN-γ的CD8(+) T细胞，但血清学上呈现T(H)2偏向，表现为高IgG1:IgG2a比值和IgE诱导。然而，使用模型分子β-半乳糖苷酶的基因枪免疫被认为相对于过敏DNA免疫可预防IgE诱导并促进T(H)1细胞。在我们当前的研究中，我们通过将β-半乳糖苷酶与两种临床相关变应原进行比较，评估了基因枪免疫预防I型过敏反应的潜力，并进一步研究了基因枪免疫对相关肺参数的影响。用编码桦树花粉变应原Bet v 1、草花粉变应原Phl p 5或模型分子β-半乳糖苷酶的质粒通过基因枪或皮内注射免疫BALB/c小鼠，随后用相应变应原进行致敏和鼻内激发。通过ELISA测定IgG1和IgG2a抗体滴度。在大鼠嗜碱性粒细胞释放试验中评估IgE水平。在支气管肺泡灌洗中测定嗜酸性粒细胞增多的严重程度，并通过肺石蜡切片的组织学分析总体浸润情况。基因枪免疫诱导了T(H)2偏向的免疫反应，在随后的致敏后并不能阻止IgE的产生。这种T(H)2效应受抗原性质的影响，与β-半乳糖苷酶相比，变应原Bet v 1和Phl p 5的T(H)2偏向更明显。用所有三种抗原进行基因枪免疫均促进嗜酸性粒细胞流入肺内，且在鼻内激发后并未减轻肺部病理状况。与引发明显T(H)1偏向和预防过敏免疫反应的质粒DNA针注射不同，基因枪应用未能诱导对所有测试抗原的抗过敏反应，因此不适合用于变应原特异性免疫治疗。
