Heterologous prime-boost: breaking the protective immune response bottleneck of COVID-19 vaccine candidates

• Published in: Emerging microbes & infections Vol. 10; no. 1; pp. 629 - 637
• Main Authors: He, Qian, Mao, Qunying, An, Chaoqiang, Zhang, Jialu, Gao, Fan, Bian, Lianlian, Li, Changgui, Liang, Zhenglun, Xu, Miao, Wang, Junzhi
• Format: Journal Article
• Language: English
• Published: United States Taylor & Francis 2021; Taylor & Francis Ltd; Taylor & Francis Group
• Subjects: Adenovirus Vaccines - administration & dosage; Adenovirus Vaccines - immunology; Adenoviruses; Animals; Antibodies; Antibodies, Neutralizing - blood; Antibodies, Neutralizing - immunology; Antibodies, Viral - blood; Antibodies, Viral - immunology; Clinical trials; COVID-19 - prevention & control; COVID-19 vaccine; COVID-19 vaccines; COVID-19 Vaccines - adverse effects; COVID-19 Vaccines - immunology; Drug dosages; Food; Heterologous prime-boost; Immune response; Immunization, Secondary - methods; Interferon-gamma - blood; Lymphocyte Count; Lymphocytes; Mice; Mice, Inbred BALB C; mRNA Vaccines; neutralizing antibody; Pandemics; Peptides; Proteins; Public health; SARS-CoV-2 - immunology; Severe acute respiratory syndrome coronavirus 2; T cell response; T-Lymphocytes - immunology; T-Lymphocytes, Helper-Inducer - immunology; th1/th2 balance; Vaccination - adverse effects; Vaccines, Subunit - administration & dosage; Vaccines, Subunit - immunology; Vaccines, Synthetic - administration & dosage; Vaccines, Synthetic - immunology; Variance analysis; COVID-19 vaccine; neutralizing antibody; th1/th2 balance; Heterologous prime-boost; T cell response
• ISSN: 2222-1751; 2222-1751
• DOI: 10.1080/22221751.2021.1902245

COVID-19 vaccines emerging from different platforms differ in efficacy, duration of protection, and side effects. To maximize the benefits of vaccination, we explored the utility of employing a heterologous prime-boost strategy in which different combinations of the four types of leading COVID-19 vaccine candidates that are undergoing clinical trials in China were tested in a mouse model. Our results showed that sequential immunization with adenovirus vectored vaccine followed by inactivated/recombinant subunit/mRNA vaccine administration specifically increased levels of neutralizing antibodies and promoted the modulation of antibody responses to predominantly neutralizing antibodies. Moreover, a heterologous prime-boost regimen with an adenovirus vector vaccine also improved Th1-biased T cell responses. Our results provide new ideas for the development and application of COVID-19 vaccines to control the SARS-CoV-2 pandemic.