Macrophages transfer functional proteins to their surface during live-cell uptake.

Macrophages transfer intact cancer cell surface proteins to their surface during live-cell uptake, significantly altering their proteome without transcriptional changes.

• Why it matters: Understanding how macrophages modify their surface proteins during cell interactions is crucial for insights into immune responses and tumor microenvironments, yet current methods cannot fully capture these processes.
• What they did: Using chemical tools and proteomics, the study demonstrated that macrophages acquire functional, intact surface proteins from cancer cells during live-cell uptake, reengineering their surface proteome.
• The result: This protein transfer process, which occurs without transcriptional activity, can influence macrophage function and metabolism, revealing a nondegradative, cell-nonautonomous mechanism of phenotypic change.