TLR9-Activating CpG-B ODN but Not TLR7 Agonists Triggers Antibody Formation to Factor IX in Muscle Gene Transfer
TLR9-Activating CpG-B ODN but Not TLR7 Agonists Triggers Antibody Formation to Factor IX in Muscle Gene Transfer
复制标题
TLR9 激活 CpG-B ODN（而非 TLR7 激动剂）在肌肉基因转移中触发针对因子 IX 的抗体形成。
DOI：
10.1089/hgtb.2019.013
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发表时间：
2019-06-01
影响因子：
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通讯作者：
Herzog, Roland W.
中科院分区：
文献类型：
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作者：
Butterfield, John S. S.;Biswas, Moanaro;Herzog, Roland W.
在基因转移中促进B细胞应答的先天免疫信号通常是不明确的。在这项研究中，我们评估了激活内体Toll样受体7，8和9（TLR 7，TLR 7/8和TLR 9）在肌肉定向基因治疗与腺相关病毒（AAV）载体的抗体形成的影响。我们检查了在小鼠中肌内施用表达人凝血因子IX的AAV 1（AAV 1-hFIX）后，通过腺嘌呤类似物CL 264（TLR 7激动剂）、咪唑喹诺酮化合物R848（TLR 7/8激动剂）或B类CpG寡脱氧核苷酸ODN 1826（TLR 9激动剂）激活内体TLR是否可以增加抗体形成。TLR 9激动剂在第1周强烈增强抗体形成，从而最初消除全身性hFIX表达。相比之下，TLR 7和TLR 7/8激动剂不显著促进抗体形成，或显著减少循环hFIX。我们同时研究了肌肉基因转移过程中这些TLR激动剂对引流淋巴结中成熟B细胞和树突状细胞（DC）的影响，包括常规DC（CD 11 B+或CD 8 α+ cDC）、单核细胞衍生的树突状细胞（moDC）和浆细胞样树突状细胞（pDC）。只有TLR 9刺激引起24 h内moDC频率的显著增加。TLR 7/8和TLR 9激动剂激活pDC（cDC的两个亚群）和成熟B细胞，而TLR 7激动剂对这些细胞仅具有轻微作用。因此，这些TLR配体对DC和成熟B细胞具有不同的作用，但只有TLR 9激动剂增强了针对AAV表达的hFIX的体液免疫应答。这些新发现表明某些TLR 9激动剂通过富集moDC在肌肉基因转移中刺激B细胞应答的独特能力。
Innate immune signals that promote B cell responses in gene transfer are generally ill-defined. In this study, we evaluate the effect of activating endosomal Toll-like receptors 7, 8, and 9 (TLR7, TLR7/8, and TLR9) on antibody formation during muscle-directed gene therapy with adeno-associated virus (AAV) vectors. We examined whether activation of endosomal TLRs, by adenine analog CL264 (TLR7 agonist), imidazolquinolone compound R848 (TLR7/8 agonist), or class B CpG oligodeoxynucleotides ODN1826 (TLR9 agonist), could augment antibody formation upon intramuscular administration of AAV1 expressing human clotting factor IX (AAV1-hFIX) in mice. The TLR9 agonist robustly enhanced antibody formation by the 1st week, thus initially eliminating systemic hFIX expression. By contrast, the TLR7 and TLR7/8 agonists did not markedly promote antibody formation, or significantly reduce circulating hFIX. We concurrently investigated the effects of these TLR agonists during muscle gene transfer on mature B cells and dendritic cells (DCs) in the draining lymph nodes including conventional DCs (CD11b+ or CD8α+ cDCs), monocyte-derived dendritic cells (moDCs), and plasmacytoid dendritic cells (pDCs). Only TLR9 stimulation caused a striking increase in the frequency of moDCs within 24 h. The TLR7/8 and TLR9 agonists activated pDCs, both subsets of cDCs, and mature B cells, whereas the TLR7 agonist had only mild effects on these cells. Thus, these TLR ligands have distinct effects on DCs and mature B cells, yet only the TLR9 agonist enhanced the humoral immune response against AAV-expressed hFIX. These new findings indicate a unique ability of certain TLR9 agonists to stimulate B cell responses in muscle gene transfer through enrichment of moDCs.