Heterolysis

Introduction

Topic sentence: Heterolysis is the breakdown of a cell or cellular material by enzymes or other lytic mechanisms that originate from a different cell or organism.

In this section, I want to differentiate heterolysis and autolysis briefly while mainly going into depth about heterolysis.

Mechanism of Heterolysis

Topic sentence: Heterolysis happens when the enzymes released by surrounding cells or organisms break down the cellular components of a target cell.

This section will explain how extracellular enzymes, including lysosomal enzymes and bacterial lysins, can degrade the membranes, proteins, and other components of another cell.

Heterolysis in Animals

Topic sentence: In animals, heterolysis can occur when immune cells use extracellular lysosomal enzymes to break down damaged or dying cells.

This section will discuss macrophages as an example, including their ability to release lysosomal enzymes to degrade dead adipocytes and other cellular material that cannot easily be engulfed.

Heterolysis in Bacteria

Topic sentence: Bacteria can also cause heterolysis by one bacterial cell producing the enzymes to lyse another bacterial cell.

This section will use Streptococcus pneumoniae as an example and focus on how competent cells produce lysins that can break down nearby susceptible cells.

Heterolysis and Cell Death

Topic sentence: Heterolysis is closely tied to the breakdown and removal of cells during certain forms of cell death.

This section will explain the relationship between heterolysis, necrosis, and the removal of cellular material while also differentiating heterolysis from processes in which the dying cell primarily contributes its own degradative enzymes .

Heterolysis Compared with Autolysis

Topic sentence: The primary distinction between heterolysis and autolysis is the origin of the enzymes responsible for cellular breakdown.

This section will directly compare the two processes in depth and further identify the source of the degradative enzymes to help distinguish them.

References

The article will cite primary research studies and reliable secondary sources describing heterolysis, including studies of macrophage-mediated cellular degradation and bacterial cell lysis.

Adigun, R., Basit, H., Zubair, M., & Murray, J. (2025, January 20). Cell liquefactive necrosis. StatPearls Publishing. NCBI Books. https://www.ncbi.nlm.nih.gov/books/NBK430935/

Hibbs, J. B. (1974). Heterocytolysis by macrophages activated by bacillus calmette-gurin: Lysosome exocytosis into tumor cells. Science, 184(4135), 468–471. https://doi.org/10.1126/science.184.4135.468

Proskuryakov, S. Y., Konoplyannikov, A. G., & Gabai, V. L. (2003). Necrosis: A specific form of programmed cell death? Experimental Cell Research, 283(1), 1–16. https://doi.org/10.1016/S0014-4827(02)00027-7

Steinmoen, H., Teigen, A., & Håvarstein, L. S. (2003). Competence-induced cells of Streptococcus pneumoniae lyse competence-deficient cells of the same strain during cocultivation. Journal of Bacteriology, 185(24), 7176–7183. https://doi.org/10.1128/JB.185.24.7176-7183.2003

Wehr, R., Lindhorst, A., Arndt, L., Krueger, M., Raulien, N., & Gericke, M. (2025). Lysosomal exocytosis by macrophages as a druggable mechanism for anti-inflammatory clearance of dead adipocytes in adipose tissue. Cell Death & Disease, 17(1). https://doi.org/10.1038/s41419-025-08334-0

Heterolysis may refer to:

• Heterolysis (biology), the apoptosis induced by hydrolytic enzymes from surrounding cells
• Heterolysis (chemistry), a chemical bond cleavage of a neutral molecule generating a cation and an anion

See also

• Homolysis (disambiguation)