原標(biāo)題：重組低致敏性B細(xì)胞表位型草花粉過(guò)敏疫苗BM32與過(guò)敏原提取物型疫苗的免疫原性比較
　　過(guò)敏原特異性免疫治療(AIT)是臨床治療過(guò)敏的一種經(jīng)濟(jì)有效的方法，可改變疾病的進(jìn)程，并具有長(zhǎng)期的效果。然而，基于過(guò)敏原提取物形式的AIT需要多次給藥，這使得治療很麻煩，導(dǎo)致患者依從性差。為了解決這一問(wèn)題，人們提出了許多方法，包括使用安全性更高的AIT材料，如類(lèi)變應(yīng)原、重組變應(yīng)原衍生物和變應(yīng)原衍生肽，這些材料可以縮短累積階段
　　在本研究中，我們研究了重組B細(xì)胞表位過(guò)敏疫苗BM32誘導(dǎo)過(guò)敏原特異性IgG抗體的能力，以及這些抗體抑制過(guò)敏患者IgE與草花粉過(guò)敏原結(jié)合的能力以及過(guò)敏原誘導(dǎo)的T細(xì)胞增殖能力。BM32重組草花粉(Phleum pratense)過(guò)敏疫苗的組成基于4個(gè)融合蛋白肽，由4種梯牧草草花粉主要過(guò)敏原(Phl p 1, Phl p 2, Phl p 5和Phl p 6) 融合到來(lái)自乙型肝炎病毒的載體蛋白，因該載體蛋白無(wú)過(guò)敏活性,因此可被注入過(guò)敏患者體內(nèi)而不必有劑量遞增階段。為研究免疫原性,我們用一個(gè)劑量(即4 個(gè)BM融合蛋白每個(gè)20μg) 對(duì)過(guò)敏病人進(jìn)行安全注射 (臨床試驗(yàn)批準(zhǔn)號(hào)：NCT01538979 NCT01445002和NCT02643641)。
　　本研究的主要發(fā)現(xiàn)是：在兔子中，皮下注射氫氧化鋁吸附的BM32三個(gè)月，誘導(dǎo)針對(duì)主要草花粉過(guò)敏原Phl p1, p Phl p5和Phl p 6 的IgG抗體水平相當(dāng)于需要注射超過(guò)8次的已注冊(cè)的基于天然過(guò)敏原提取物的草花粉過(guò)敏疫苗(Allergovit草;Allergopharma、Reinbek、德國(guó);Alutard SQ混合草;ALK-Abello、H?rsholm、丹麥;以及光草+黑麥;Stallergenes、安東尼、法國(guó);參見(jiàn)本文在線(xiàn)存儲(chǔ)庫(kù)中的方法部分，網(wǎng)址為www.jacionline.org;圖1)所誘導(dǎo)的IgG抗體的水平，而Pollinex (Pollinex四極體+禾本科+黑麥，Bencard Allergie GmbH德國(guó)慕尼黑,一種基于4種注射劑的疫苗)幾乎沒(méi)有反應(yīng)。重要的是，BM32誘導(dǎo)的phlp2特異性IgG抗體水平高于任何已注冊(cè)的基于過(guò)敏原提取物的疫苗(圖1)。
　　我們認(rèn)為這是一個(gè)重要的發(fā)現(xiàn),因?yàn)橐炎C明第二組草花粉主要過(guò)敏原被60%以上草花粉過(guò)敏患者識(shí)別, 通過(guò)皮膚試驗(yàn)發(fā)現(xiàn)，比其他草花粉過(guò)敏原具有更高的過(guò)敏效力。因此，我們的研究結(jié)果表明，只需少量注射(即3-5次)BM32，就有可能建立足夠水平的草花粉過(guò)敏原特異性IgG反應(yīng)，而傳統(tǒng)的過(guò)敏疫苗需要兩倍以上的增加劑量注射。舌下治療甚至需要每日服用。因此，我們認(rèn)為基于BM32的治療方案將更方便患者，并增加患者的依從性。
　　在IgE抑制實(shí)驗(yàn)中，BM32誘導(dǎo)的IgG阻斷IgE與phlp2結(jié)合的效果明顯好于商業(yè)疫苗誘導(dǎo)的IgG抗體(p = .0008，圖2)，因此可以認(rèn)為BM32在保護(hù)第二組過(guò)敏原引起的癥狀方面可能優(yōu)于基于提取物的疫苗。最后，我們還可以證明BM32誘導(dǎo)的抗體可以抑制特定的草花粉過(guò)敏原誘導(dǎo)的T細(xì)胞增殖(參見(jiàn)本文的方法部分和圖E3，見(jiàn)www.jacionline.org的在線(xiàn)知識(shí)庫(kù))，這表明BM32可能對(duì)T細(xì)胞介導(dǎo)的草花粉過(guò)敏的遲發(fā)相癥狀也有有益的影響。然而，我們的研究的一個(gè)局限性是，我們?cè)谠紕?dòng)物中進(jìn)行了免疫原性研究，因此可能對(duì)已經(jīng)致敏的患者存在差異。
　　綜上所述，我們的免疫原性研究表明，與天然的基于過(guò)敏原提取物的疫苗相比，誘導(dǎo)草花粉過(guò)敏原特異性保護(hù)性抗體反應(yīng)所需的BM32注射量要少得多，而且在疫苗中使用載體蛋白有助于克服第二組過(guò)敏原免疫原性差的問(wèn)題。鑒于BM32具有較強(qiáng)的抗過(guò)敏活性，人們可能認(rèn)為BM32是一種優(yōu)于基于過(guò)敏原提取物疫苗的草花粉過(guò)敏疫苗。
延伸閱讀
JACI                                                                    
Comparison of the immunogenicity of BM32, a recombinant hypoallergenic B cell epitope–based grass pollen allergy vaccine with allergen extract–based vaccines
DOI: https://doi.org/10.1016/j.jaci.2017.03.048|
Abstract:
Allergen-specific immunotherapy (AIT) is a clinically and cost-effective allergy treatment that modifies the course of the disease and has long-lasting effects.1x1Cox, L., Calderón, M., and Pfaar, O. Subcutaneous allergen immunotherapy for allergic disease: examining efficacy, safety and cost-effectiveness of current and novel formulations. Immunotherapy. 2012; 4: 601–616
Crossref | PubMed | Scopus (31) | Google ScholarSee all References, E7xE7Jutel, M., Agache, I., Bonini, S., Burks, A.W., Calderon, M., Canonica, W. et al. International consensus on allergy immunotherapy. J Allergy Clin Immunol. 2015; 136: 556–568
Abstract | Full Text | Full Text PDF | PubMed | Scopus (201) | Google ScholarSee all References, E8xE8Jacobsen, L., Niggemann, B., Dreborg, S., Ferdousi, H.A., Halken, S., Host, A. et al. Specific immunotherapy has long-term preventive effect of seasonal and perennial asthma: 10-year follow-up on the PAT study. Allergy. 2007; 62: 943–948
Crossref | PubMed | Scopus (617) | Google ScholarSee all References However, allergen extract–based forms of AIT require administration of multiple doses, which makes treatment cumbersome and leads to poor compliance in patients.2x2Keil, M.A., R?der, E., Gerth van Wijk, R., Al, M.J., Hop, W.C., and Rutten-van M?lken, M.P. Real-life compliance and persistence among users of subcutaneous and sublingual allergen immunotherapy. J Allergy Clin Immunol. 2013; 132: 353–360
Abstract | Full Text | Full Text PDF | PubMed | Scopus (115) | Google ScholarSee all References A number of approaches were proposed to address this issue, including use of AIT materials with higher safety, such as allergoids, recombinant allergen derivatives, and allergen-derived peptides, which allow shortening of the build-up phase.E9 In this study we have investigated the ability of the recombinant B cell epitope–based allergy vaccine BM32 to induce allergen-specific IgG antibodies and the ability of these antibodies to inhibit allergic patients' IgE binding to grass pollen allergens, as well as allergen-induced T-cell proliferation. BM32 is a recombinant grass pollen (Phleum pratense) allergy vaccine based on 4 fusion proteins consisting of peptides from the 4 major timothy grass pollen allergens (Phl p 1, Phl p 2, Phl p 5, and Phl p 6) fused to the PreS carrier protein from hepatitis B, which lacks relevant allergenic activityE10xE10Niederberger, V., Marth, K., Eckl-Dorna, J., Focke-Tejkl, M., Weber, M., Hemmer, W. et al. Skin test evaluation of a novel peptide carrier-based vaccine, BM32, in grass pollen-allergic patients. J Allergy Clin Immunol. 2015; 136: 1101–1103
Abstract | Full Text | Full Text PDF | PubMed | Scopus (26) | Google ScholarSee all References and therefore can be injected into allergic patients without need for updosing.3x3Focke-Tejkl, M., Weber, M., Niespodziana, K., Neubauer, A., Huber, H., Henning, R. et al. Development and characterization of a recombinant, hypoallergenic, peptide-based vaccine for grass pollen allergy. J Allergy Clin Immunol. 2015; 135: 1207–1217 (e1-11)
Abstract | Full Text | Full Text PDF | PubMed | Google ScholarSee all References, 4x4Zieglmayer, P., Focke-Tejkl, M., Schmutz, R., Lemell, P., Zieglmayer, R., Weber, M. et al. Mechanisms, safety and efficacy of a B cell epitope-based vaccine for immunotherapy of grass pollen allergy. EBioMedicine. 2016; 11: 43–57
Abstract | Full Text | Full Text PDF | PubMed | Scopus (43) | Google ScholarSee all References For our immunogenicity studies, we have used a dose (ie, 20 μg of each of the 4BM fusion proteins) that has been safely administered to allergic patients (ClinicalTrials.gov identifiers NCT01445002, NCT01538979, and NCT02643641).4 x4Zieglmayer, P., Focke-Tejkl, M., Schmutz, R., Lemell, P., Zieglmayer, R., Weber, M. et al. Mechanisms, safety and efficacy of a B cell epitope-based vaccine for immunotherapy of grass pollen allergy. EBioMedicine. 2016; 11: 43–57
Abstract | Full Text | Full Text PDF | PubMed | Scopus (43) | Google ScholarSee all ReferencesThe main finding of our current study was that 3 monthly subcutaneous injections of aluminum hydroxide–adsorbed BM32 induced IgG antibody levels to the major grass pollen allergens Phl p 1, Phl p 5, and Phl p 6 in rabbits, which were comparable with natural allergen extract–based registered grass pollen allergy vaccines requiring more than 8 injections (Allergovit grass; Allergopharma, Reinbek, Germany; Alutard SQ grass mix; ALK-Abelló, H?rsholm, Denmark; and Phostal grasses + rye; Stallergenes, Antony, France; see the MethodsMethods section in this article's Online Repository at www.jacionline.org; Fig 1Fig 1), whereas almost no response was observed with Pollinex (Pollinex Quattro Plus grasses + rye; Bencard Allergie GmbH, Munich, Germany), a vaccine based on 4 injections. Importantly, BM32 induced higher levels of Phl p 2–specific IgG antibodies than any of the registered allergen extract–based vaccines (Fig 1Fig 1). We consider this an important finding because it has been shown that group 2 allergens are major grass pollen allergens recognized by more than 60% of patients with grass pollen allergy and, when compared with the other grass pollen allergens by using skin testing, were found to show high allergenic potency.5x5Westritschnig, K., Horak, F., Swoboda, I., Balic, N., Spitzauer, S., Kundi, M. et al. Different allergenic activity of grass pollen allergens revealed by skin testing. Eur J Clin Invest. 2008; 38: 260–267
Crossref | PubMed | Scopus (42) | Google ScholarSee all References Thus our results indicate that it should be possible to build up sufficient levels of grass pollen allergen–specific IgG responses with only few injections (ie, 3-5) of BM32, whereas traditional allergy vaccines require more than double the number of updosing injections. Sublingual treatment even requires daily administration. Therefore we think that the treatment schedules based on BM32 will be more convenient for patients and should increase their compliance. In the IgE inhibition experiments BM32-induced IgG blocked IgE binding to Phl p 2 significantly better than IgG antibodies induced by the commercial vaccines (P = .0008, Fig 2Fig 2). Therefore one might assume that BM32 could be superior to the extract-based vaccines regarding protection of group 2 allergen–induced symptoms. Finally, we also could demonstrate that BM32-induced antibodies inhibited specifically grass pollen allergen–induced T-cell proliferation (see the MethodsMethods section and Fig E3Fig E3 in this article's Online Repository at www.jacionline.org), which suggests that BM32 might also have beneficial effects on T cell–mediated late-phase symptoms of grass pollen allergy. However, a limitation of our study is that we performed the immunogenicity study in naive animals, and therefore there might be differences regarding already sensitized patients.
In summary, our immunogenicity studies indicate that induction of grass pollen allergen–specific protective antibody responses requires considerably fewer injections of BM32 compared with natural allergen extract–based vaccines and that the use of carrier proteins in the vaccine helps to overcome the poor immunogenicity of group 2 allergens. Given the strong reduction of allergenic activity of BM32, one might expect that BM32 represents a grass pollen allergy vaccine that could be superior to allergen extract–based vaccines.
Authors:
Milena Weber Katarzyna Niespodziana Birgit Linhart Angela Neubauer ,
Hans Huber Rainer Henning Rudolf Valenta
　　創(chuàng)建過(guò)敏性疾病的科研、科普知識(shí)交流平臺(tái)，為過(guò)敏患者提供專(zhuān)業(yè)診斷、治療、預(yù)防的共享平臺(tái)。