How Invertebrates Fight Infections: Antimicrobial Peptides and Ancient Immune Defense | Research

The takeaway

Invertebrate innate immunity relies on phagocytes and antimicrobial peptides as the first line of pathogen defense, offering insights into ancient and conserved immune mechanisms.

Ancient defense systems
Invertebrate antimicrobial peptides represent hundreds of millions of years of evolved pathogen defense

What the researchers found

Invertebrate innate immunity relies on diverse phagocytic cells and antimicrobial peptides that represent ancient, conserved defense mechanisms against pathogens.

Why it matters

Invertebrate antimicrobial peptides evolved over hundreds of millions of years of pathogen warfare. Understanding them could reveal new antimicrobial strategies and fundamental principles of immune defense.

The numbers in context

Reviews TLRs, NLRs, scavenger receptors, phagocytes (amebocytes, hemocytes, coelomocytes), and antimicrobial peptides across invertebrate groups.

How the study worked

Review chapter examining innate immune mechanisms across invertebrate phyla, including cellular receptors, phagocytes, and antimicrobial peptide systems.

Who was studied

Invertebrate species

What this study cannot tell us

Broad overview chapter — lacks depth on specific species or peptide families. Direct therapeutic applications for human medicine are not addressed.

How to read the evidence

Review chapter providing a broad overview of invertebrate innate immunity. Draws on established comparative immunology literature.

When this study was published

Published in 2025 in Advances in Experimental Medicine and Biology, summarizing current understanding of invertebrate immune systems.

The bigger picture

Invertebrate immune systems are a vast, largely untapped source of antimicrobial compounds and immune strategies that could inspire new approaches to fighting human infections.

Questions still open

Which invertebrate antimicrobial peptides have the most potential for human therapeutic applications?
How have invertebrate immune systems adapted to specific pathogen threats in different environments?

Common questions

How do invertebrates fight infections without an adaptive immune system?

Invertebrates rely entirely on innate immunity — pattern recognition receptors detect pathogens, phagocytic cells engulf and destroy them, and antimicrobial peptides directly kill microbes. These ancient defense mechanisms are remarkably effective.

Why should we study invertebrate immunity?

Invertebrate antimicrobial peptides have been fighting bacteria for hundreds of millions of years, making them a rich source of new antimicrobial compounds. Understanding these systems also reveals fundamental immune principles conserved in all animals, including humans.

Read the original research

Exploring the Innate Immunity in Invertebrates.

Advances in experimental medicine and biology, 1476, 411-423

View on PubMed ↗Publisher’s paper ↗

Citation

Perveen, Nighat; Kishore, Uday; Al Aiyan, Ahmad; Willingham, Arve Lee; Mohteshamuddin, Khaja. (2025). Exploring the Innate Immunity in Invertebrates.. Advances in experimental medicine and biology, 1476, 411-423. https://doi.org/10.1007/978-3-031-85340-1_16