Skin keratinocytes pre-store antimicrobial peptides in lamellar bodies. On injury, they're released within minutes. The full adaptive immune response takes days to mobilize, by the time T cells and antibodies arrive, AMPs have already been on the front line.
This is the first job peptides do: act fast, act local, act precise.
What is a peptide?
A peptide is a signal. The body manufactures signals from just 20 amino acid building blocks, arranged in specific sequences. Change the sequence, and the signal changes completely. The body uses the same ingredients to spell STOP and POST, and the meanings are entirely different.
The body runs 7,000 distinct signals this way.
Five Famous Peptide Signals
Some peptide signals regulate the biggest processes in the body.
Insulin responds to rising blood sugar and tells the body to absorb glucose. When insulin declines, the body feels hungry (ghrelin), and then full (leptin). These three peptides alone manage feeding, fasting, and energy.
Other peptides manage sensation and response. Endorphins dull pain when the body sustains injury. Substance P carries pain signals between neurons. These peptide signals work fast, often within seconds.
Wound peptides (antimicrobial peptides) are the first responders. Released directly at the site of injury, they hunt bacteria before infection takes hold. They don't travel through the blood. They work at the site of damage.
The Precision That Changed Medicine
The body relies on thousands of these signals, all built from the same 20 building blocks. This specificity is what makes peptide drugs so powerful.
A peptide designed to signal fullness does not accidentally trigger pain. A peptide designed to manage appetite does not accidentally impair tissue repair. The signal is precise. The lock-and-key fit is tight. Peptide drugs have higher clinical trial success rates than many conventional drugs because they work with the body's own targeting system.
How Peptide Drugs Work
Peptide drugs follow one pattern: start with signals the body already uses. Learn what those signals do. Then extend how long they stay active. The body has been running these signals for millions of years through evolution. Medicine simply learned to manufacture them and make them last longer.
The result is drugs that work the way the body intended, just more reliably and for longer periods.