SERPINA1 and infection: Albeit most of these genes were also significantly enriched in the “brightest” Mab2C1-stained cells after infection with Lib1 (Figure S4), a second round of enrichment with Lib2 showed a selection process (Figures S3 and S4C) and strongly reassured the important role of the “cargo loading into COPII-coated vesicle” cluster in the intracellular levels of α1AT polymers.