GSE191089
Comprehensive comparison of adaptive immune response by inactivated SARS-CoV-2 vaccine between young and old
Purpose:  Construction of a SARSCoV2 vaccine TCR specific machine learning model using single-cell TCR technology sequencing Methods:PBMCs were isolated from peripheral venous blood of HLA-A2+ healthy donors. PBMCs were incubated with antibody cocktail and then RapidSpheres, then the magnet was applied and unbound CD8+ T cells were recovered from the supernatant. According to the above method of CD8+ T activation, CD8+ T cells specific for ancestral epitopes were obtained by stimulating with the corresponding mutant ancestral peptides. Activation-specific CD8+ T cells were labeled with tetramers-PE and CD8-APC and then sorted out by flow cytometer FACS Canto (BD). The following protocol describes surface protein staining with hashtag antibodies for protein detection outside of the single cell V(D)J signature barcoding technique for differentiating CD8+ T cells with different epitope specificities after mixing up samples. The following is the hashtag information corresponding to the ancestral epitopes of the mutant strains. B.1.1.7 corresponds to the ancestral epitope ORF1a 1707-16 , ORF1a 2225-34 , ORF1a 2230-38. B.1.617.2 corresponds to the ancestral epitope M 82-90 . B.1.617.3 corresponds to the ancestral epitope ORF1a 2240-49, ORF1a 3683-92 , and ancestral epitope S 2-11 of B.1.526.2 without labeled hashtag protein. Cell number and viability were checked after surface protein hashtag staining (cell viability > 80%). Then droplet-encapsulation single-cell sequencing experiments were performed, and 10,000 living single cells were loaded onto each of the Chromium Controller (10x Genomics). After droplet-encapsulation, single-cell cDNA synthesis, amplification and sequencing libraries were generated using Chromium Single Cell 5' Feature Barcode Library Kit (10x Genomics),Chromium The result showed the inactivated vaccine is less protective in older adults, who take longer to develop effective antibodies, and the TCR diversity of each epitope specific repertoire decreased in the elderly. In addition, we found inactivated vaccines could stimulate the proliferation of related B cells in the body, thereby reducing the diversity of BCR in the body. Compared with the young, the elderly is less likely to produce antibody related BCR clones and the same is true for TCR diversity. Conclusions: The result showed the inactivated vaccine is less protective in older adults, who take longer to develop effective antibodies, and the TCR diversity of each epitope specific repertoire decreased in the elderly. In addition, we found inactivated vaccines could stimulate the proliferation of related B cells in the body, thereby reducing the diversity of BCR in the body. Compared with the young, the elderly is less likely to produce antibody related BCR clones and the same is true for TCR diversity. Overall design: single-cell RNA-seq and TCR-seq