scRNA-seq analysis of mouse splenic CD8 T cells 1 month post transfer of CD8 T cells from 3 months old donor into 24 months old recipient

Aging is associated with systemic chronic inflammation (inflammaging) that leads to impaired physiological functions and vulnerability to several diseases. However, underlying alterations in aged immune system resulting in gradual loss of immune fitness remain unclear. Using a combination of CD8 T cell transfer from young to old and from old to young mice and single-cell RNA sequencing, we characterized the age-associated alterations in CD8 T cells. We transferred 2 millions of purified CD8+ T cells pooled from 3 CD45.1 C57BL/6J 3 months old female mice (donor) by i.v. injection into CD45.2 C57BL/6J 24 months old female mouse (recipient) and sorted CD45.1+CD3e+CD8a+ and CD45.2+CD3e+CD8a+ T cells from the spleen 1 month post transfer to perform scRNA/TCR-seq. Droplet-based 5′ end massively parallel single-cell RNA sequencing was performed by isolating mouse CD45.1+ CD3e+CD8a+ (3 months old donor) and CD45.2+CD3e+CD8a+ (24 months old recipient) cells sorted by FACS from the spleen and 5'GEX and TCR libraries were prepared using Chromium Single Cell 5′ Reagent Kits according to manufacturer’s protocol (10x Genomics). The generated scRNAseq libraries were sequenced using NovaSeq S4 sequencers. Mouse CD45.1+CD3e+CD8a+ (young donor) and CD45.2+CD3e+CD8a+ (old recipient) T cells from the spleen 1 month post transfer sorted, processed and sequensed