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Updated: Dec 16, 2025
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Study of Protein-protein Interactions in Autophagy Research
Published on: September 9, 2017
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Outside in: Roles of complement in autophagy
Ben C King1, Klaudia Kulak1, Lucie Colineau1
1Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö, Sweden.
British Journal of Pharmacology
|July 5, 2020
Summary
The complement system, a protein cascade, signals cells to remove pathogens and waste. It also triggers autophagy, a cellular process, to eliminate intracellular threats and internal waste.
Area of Science:
- Immunology
- Cell Biology
Background:
- The complement system is a key extracellular defense mechanism.
- It signals host cells via surface receptors to clear pathogens and waste.
- Its role in intracellular processes is an emerging area of research.
Purpose of the Study:
- To review the dual role of the complement system in autophagy.
- To explore complement's function in both protective and targeted cellular responses.
- To highlight recent findings on intracellular complement activity.
Main Methods:
- Literature review of complement system and autophagy research.
- Analysis of signaling pathways linking complement activation to autophagy.
- Synthesis of evidence for intracellular complement functions.
Main Results:
- Extracellular complement activation induces homeostatic and antimicrobial autophagy.
- Complement proteins can signal across cell membranes to trigger autophagy.
- Emerging evidence suggests intracellular roles for complement in waste disposal.
Conclusions:
- The complement system is a critical regulator of cellular autophagy.
- Complement influences both extracellular defense and intracellular homeostasis.
- Further research is needed to fully elucidate intracellular complement functions.
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