Protein Quantification and Visualization

Total proteins isolated from cells or tissues were separated by electrophoresis and transferred to blotting membranes as described elsewhere [5 (link),13 (link)]. The membranes were preblocked, incubated overnight with antibodies to MARCO, TIM4, CD68, or GAPDH (anti-MARCO—ab 256822, 1:200; anti-TIM4—ab47637, anti-CD68-ab ab125212, anti-GAPDH—sc-25778, Abcam, Cambridge, UK), washed, and incubated with HRP-conjugated antibodies (Bio-Rad, Hercules, CA, USA). The bands were developed with Novex ECL Kit (Thermo Fisher, Waltham, MA, USA) in a ChemiDoc™ system (Bio-Rad, Hercules, CA, USA). The densitometry was carried out using ImageLab Software (Bio-Rad, Hercules, CA, USA) against GAPDH as a reference protein. For an image of the uncropped membrane after blotting, see Supplementary Material (Figure S2).