SARS-CoV-2 vaccination-infection pattern imprints and diversifies T cell differentiation and neutralizing response against Omicron subvariants

This study investigated the impact of different SARS-CoV-2 vaccination and infection histories on the immune response to Omicron subvariants. Omicron breakthrough infection, regardless of prior mRNA or inactivated vaccination, resulted in higher neutralizing antibody levels and stronger T-cell responses compared to Delta breakthrough infection after inactivated vaccination. Different vaccination-infection patterns influenced T-cell differentiation, with mRNA vaccination followed by Omicron infection showing higher levels of specific CD4⁺ T cells. Breakthrough infection groups exhibited enhanced T-cell proliferation and multi-functionality. The study suggests that Omicron's higher immunogenicity may have contributed to the replacement of the Delta variant. The findings advance understanding of immune imprinting and inform future vaccination strategies.

Junxiang Wang, Kaiyi Li, Xinyue Mei, Jinping Cao, Jiaying Zhong, Peiyu Huang, Qi Luo, Guichang Li, Rui Wei, Nanshan Zhong, Zhu Xiang Zhao, Zhongfang Wang