Multiomics analysis on polyamine metabolisms in colorectal cancer indicates important contribution of impaired anti-tumor activities of CXCR6⁺CD8⁺T cells by the extracellular putrescine

The models were reconstructed to randomly obtain three colons in each group. Lamina propria mononuclear cells (LPMC) were extracted as previously described (Wei et al. 2024). Whole cells from the colons were isolated using the RWD Intestine Enzymolysis Kit (DHIE-5007). The LPMC and whole cells with number ratio 1:1 were pooled into single-cell suspension for downstream construction of scRNA-seq libraries using a SeekOne® Digital Droplet single-cell 3’ transcriptome kit (SeekOne, Beijing) according to the manufacturer’s instructions. The scRNA-seq libraries were sequenced at Novogene (Co. Ltd., Beijing, China). The processing of the raw reads followed the same protocol as described previously (Shi et al. 2024). The downstream analysis in R software, including the quality filter, cluster annotation, and DEGs, was the same as mentioned above.