评估单域抗体作为靶向疫苗递送至小肠上皮细胞的载体。
Evaluating single-domain antibodies as carriers for targeted vaccine delivery to the small intestinal epithelium.
机构信息
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium; VIB Center for Plant Systems Biology, 9052 Gent, Belgium.
Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium.
出版信息
J Control Release. 2020 May 10;321:416-429. doi: 10.1016/j.jconrel.2020.01.033. Epub 2020 Jan 22.
Targeting a vaccine to the mucosal surface has recently been recognized as a promising approach to efficiently induce mucosal immune responses against enteric pathogens. However, poor uptake and inefficient transport of orally delivered subunit vaccines across the intestinal epithelium combined with weak immune responses still present important bottlenecks for mucosal vaccination. A possible strategy suggested to surmount these hurdles is to target the selected antigen to transcytotic receptors, such as aminopeptidase N (APN) present on enterocytes and antigen-presenting cells (APCs). Therefore, we aimed to identify potent and selective VHHs against porcine aminopeptidase N (pAPN), that were fused to the fragment crystallizable (Fc) domain of the murine IgG2a, resulting in dimeric VHH-MG fusions. Out of a library of 30 VHH-MG fusion candidates, two fusions displaying the best binding on pAPN-expressing cells were selected and showed in vivo internalization across the porcine gut epithelium. One of these fusions triggered systemic and intestinal IgA responses upon oral administration. Our results demonstrate the potential of bivalent VHH-MG fusions as delivery vehicles for vaccine antigens. VHH-mediated targeting of antigens to APN to generate protective immunity at the mucosal surface remains to be further validated.
将疫苗靶向黏膜表面最近被认为是一种很有前途的方法,可以有效地诱导针对肠道病原体的黏膜免疫反应。然而,口服给予的亚单位疫苗在穿过肠上皮细胞时摄取不良和转运效率低,加上弱的免疫反应,这仍然是黏膜疫苗接种的重要瓶颈。为了克服这些障碍,一种可能的策略是将选定的抗原靶向到转胞吞受体,例如肠上皮细胞和抗原呈递细胞(APCs)上存在的氨肽酶 N(APN)。因此,我们旨在鉴定针对猪氨肽酶 N(pAPN)的有效且具有选择性的 VHH,这些 VHH 与鼠 IgG2a 的片段结晶(Fc)结构域融合,形成二聚体 VHH-MG 融合物。在 30 个 VHH-MG 融合候选物的文库中,选择了两个在表达 pAPN 的细胞上显示最佳结合的融合物,并显示在体内穿过猪肠道上皮细胞内化。其中一种融合物在口服给予时引发了全身和肠道 IgA 反应。我们的结果证明了二价 VHH-MG 融合物作为疫苗抗原传递载体的潜力。VHH 介导的将抗原靶向 APN 以在黏膜表面产生保护性免疫的方法仍有待进一步验证。