Local and systemic immune responses induced by intranasal immunization with biomineralized foot-and-mouth disease virus-like particles

Shuo Li; Ruichong Zhao; Hetao Song; Songjia Pan; Yun Zhang; Hu Dong; Manyuan Bai; Shiqi Sun; Huichen Guo; Shuanghui Yin

doi:10.3389/fmicb.2023.1112641

Local and systemic immune responses induced by intranasal immunization with biomineralized foot-and-mouth disease virus-like particles

Front Microbiol. 2023 Feb 3:14:1112641. doi: 10.3389/fmicb.2023.1112641. eCollection 2023.

Authors

Shuo Li¹, Ruichong Zhao¹, Hetao Song¹, Songjia Pan¹, Yun Zhang¹, Hu Dong¹, Manyuan Bai¹, Shiqi Sun¹, Huichen Guo^{1

2

3}, Shuanghui Yin¹

Affiliations

¹ State Key Laboratory of Veterinary Etiological Biology, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China.
² College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
³ Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, China.

Abstract

Introduction: Foot-and-mouth disease virus (FMDV) infects the host by invading mucosal epithelial cells of the respiratory or digestive tract. Therefore, establishing a specific antiviral mucosal immune barrier can effectively block viral invasion.

Methods: We evaluated local mucosal and systemic immune responses elicited by intranasal immunization of mice with foot-and-mouth disease (FMD) calcium phosphate mineralized virus-like particles (CaP-VLPs) and tested whether three commercial mucosal adjuvants enhanced the immunogenicity of the antigen. The biosafety of the vaccine was verified through gross observation and pathological analysis of the lungs.

Results: CaP-VLPs effectively induced secretion of IgA (sIgA) from multiple sites in mouse mucosa and produced anti-FMD-specific IgG in the serum. Splenic lymphocytes specifically proliferated and secreted IFN-γ following antigen stimulation, indicating the vaccine can induce a certain level of cellular immune response. Finally, the pathological examination confirmed that CaP-VLPs did not cause substantial damage to the lungs of animals after immunization via mucosal administration. Notably, the vaccine mixed with S adjuvant increased the content of sIgA and serum IgG, and the high level of IgG in serum was maintained at least 7 weeks.

Discussion: Overall, this study reveals that FMD CaP-VLPs can induce good local mucosal immune and systemic immune response through intranasal immunization, and the immune response was specifically enhanced by S adjuvant. These data support that CaP-VLPs-S as a candidate mucosal vaccine for the prevention of FMD vaccine infection.

Keywords: adjuvant; biomineralization; foot-and-mouth disease virus; mucosal immunity; virus-like particles.