Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester, NY, USA.
Innate Immun. 2018 May;24(4):240-251. doi: 10.1177/1753425918771178. Epub 2018 Apr 19.
Each year millions of neonates die due to vaccine preventable infectious diseases. Our study seeks to develop novel neonatal vaccines and improve immunogenicity of early childhood vaccines by incorporating TLR agonist-adjuvant combinations that overcome the inherent neonatal Th2 bias and stimulate Th1 polarizing response from neonatal APCs. We systematically stimulated cord blood mononuclear cells with single and multiple combinations of TLR agonists and measured levels of IL-12p70, IFN-γ, IFN-α, IL-10, IL-13, TNF-α, IL-6 and IL-1β from cell culture supernatants. APC-specific surface expression levels of costimulatory markers CD40, CD83 and PD-L1 were assessed by flow cytometry. Whole blood assays were included to account for the effect of plasma inhibitory factors and APC intracellular TNF-α and IL-12p40 secretions were measured. We found robust Th1 polarizing IL-12p70, IFN-γ and IFN-α responses when cord blood APCs were stimulated with TLR agonist combinations that contained Poly I:C, Monophosphoryl Lipid A (MPLA) or R848. Addition of class A CpG oligonucleotide (ODN) to Th1 polarizing TLR agonist combinations significantly reduced cord blood IL-12p70 and IFN-γ levels and addition of a TLR2 agonist induced significantly high Th2 polarizing IL-13. Multi-TLR agonist combinations that included R848 induced lower inhibitory PD-L1 expression on cord blood classical dendritic cells than CpG ODN-containing combinations. Incorporation of combination adjuvants containing TLR3, TLR4 and TLR7/8 agonists to neonatal vaccines may be an effective strategy to overcome neonatal Th2 bias.
每年都有数百万新生儿因可通过疫苗预防的传染病而死亡。我们的研究旨在开发新型新生儿疫苗，并通过将 TLR 激动剂-佐剂组合结合起来，改善儿童早期疫苗的免疫原性，这些组合克服了新生抗原呈递细胞（APC）固有地偏向 Th2 的特点，并刺激 Th1 极化反应。我们系统地用单个和多个 TLR 激动剂组合刺激脐血单核细胞，并从细胞培养上清液中测量白细胞介素-12p70、干扰素-γ、干扰素-α、白细胞介素-10、白细胞介素-13、肿瘤坏死因子-α、白细胞介素-6 和白细胞介素-1β的水平。通过流式细胞术评估 APC 特异性表面共刺激分子 CD40、CD83 和 PD-L1 的表达水平。进行全血检测以考虑血浆抑制因子和 APC 细胞内 TNF-α和 IL-12p40 分泌的影响。我们发现，当用含有聚肌苷酸、单磷酰脂质 A（MPLA）或 R848 的 TLR 激动剂组合刺激脐血 APC 时，会产生强大的 Th1 极化白细胞介素-12p70、干扰素-γ和干扰素-α反应。在 Th1 极化 TLR 激动剂组合中添加 A 类 CpG 寡核苷酸（ODN）会显著降低脐血白细胞介素-12p70 和干扰素-γ水平，而添加 TLR2 激动剂会诱导明显的 Th2 极化白细胞介素-13。包含 R848 的多 TLR 激动剂组合诱导的脐血经典树突状细胞上的抑制性 PD-L1 表达低于含 CpG ODN 的组合。将包含 TLR3、TLR4 和 TLR7/8 激动剂的组合佐剂纳入新生儿疫苗可能是克服新生儿 Th2 偏向的有效策略。
