Cellular Fitness Fingerprints: How Tissues Maintain Quality Control

Not all cells are equal — and tissues have mechanisms to tell the difference.
"Fitness fingerprints" (surface markers like Flower protein, Dectin-1, etc.) allow cells to signal their functional state to neighbors. This enables competitive elimination of damaged cells without tissue-wide disruption.
What if age-related decline is partly a failure of cellular competition — not just accumulation of damage, but loss of the quality control systems that normally clear it?