Mao Jie, Eom Gi-Deok, Yoon Keon-Woong, Kang Hae-Ji, Chu Ki-Back, Quan Fu-Shi
Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea.
Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea.
Life (Basel). 2022 Jun 29;12(7):975. doi: 10.3390/life12070975.
Both sublingual (SL) and oral vaccine administration modalities are convenient, easy, and safe. Here, we have investigated the differences in vaccine efficacy that are induced by oral and sublingual immunization with live influenza virus (A/Hong Kong/1/1968, H3N2) in mice. Intranasally administering a lethal dose of the influenza virus resulted in the deaths of the mice, whereas viral replication in the lungs did not occur upon SL or oral administration. At 30 days post-immunization through the SL or oral route, the mice were intranasally challenge-infected with the lethal dose of the homologous influenza virus. Both SL and oral immunizations with the influenza virus elicited significantly higher levels of virus-specific IgG and IgA antibody responses, as well as HAI titers in the sera. Upon challenge infection, the SL immunization elicited higher levels of pulmonary IgG antibody and CD8 T cell responses than the oral immunization. Enhanced splenic germinal center B (GC B) and B cell proliferation were also detected from the SL immunization, both of which were significantly greater than those of the oral immunization. Importantly, compared to oral immunization, significantly lessened lung viral loads and bodyweight reductions were observed from the SL immunization and these parameters contributed to prolonging the survival of the immunized mice. These results indicate that both SL and oral administration could be effective routes in inducing protective immunity against influenza virus infection, with SL immunization being the better of the two delivery routes.
舌下（SL）和口服疫苗接种方式都方便、易行且安全。在此，我们研究了用甲型流感病毒（A/香港/1/1968，H3N2）对小鼠进行口服和舌下免疫所诱导的疫苗效力差异。经鼻内给予致死剂量的流感病毒导致小鼠死亡，而通过舌下或口服给药时，肺部未发生病毒复制。在通过舌下或口服途径免疫30天后，给小鼠经鼻内用致死剂量的同源流感病毒进行攻击感染。用流感病毒进行舌下和口服免疫均能显著诱导更高水平的病毒特异性IgG和IgA抗体反应以及血清中的血凝抑制（HAI）效价。在攻击感染后，舌下免疫诱导的肺部IgG抗体水平和CD8 T细胞反应高于口服免疫。从舌下免疫中还检测到脾脏生发中心B（GC B）细胞和B细胞增殖增强，两者均显著高于口服免疫。重要的是，与口服免疫相比，舌下免疫的肺部病毒载量显著降低，体重减轻也减少，这些参数有助于延长免疫小鼠的存活时间。这些结果表明，舌下和口服给药都可能是诱导针对流感病毒感染的保护性免疫的有效途径，其中舌下免疫是两种给药途径中效果更好的。
