Chemoattractants, extracellular proteases, and the integrated host defense response

Area of Science:

• Biochemistry
• Immunology
• Molecular Biology

Background:

• Extracellular proteases play a crucial role in host defense mechanisms, including blood clotting, fibrinolysis, and complement activation.
• Proteases released during inflammation and immunity are essential for regulating immune cell function and response.
• Post-translational control by proteases allows for rapid enzymatic regulation of target proteins, influencing cellular processes.

Purpose of the Study:

• To review the literature on a novel class of proteolytic targets: leukocyte chemoattractants.
• To highlight the role of chemerin, a key chemoattractant for dendritic cells and macrophages, and its activation by serine proteases.
• To explore the impact of protease-mediated modulation of chemoattractant activity on the immune response.

Main Methods:

• Literature review of emerging research on extracellular proteases and leukocyte chemoattractants.
• Analysis of the activation pathways of chemerin by serine proteases from coagulation, fibrinolytic, and inflammatory cascades.
• Discussion of the functional consequences of chemoattractant modulation on leukocyte recruitment and positioning.

Main Results:

• Leukocyte chemoattractants represent a novel class of targets for extracellular proteases.
• Chemerin, a chemoattractant for dendritic cells and macrophages, is activated by serine proteases involved in key physiological cascades.
• Protease-mediated modulation of chemoattractant activity can profoundly affect leukocyte positioning and immune responses.

Conclusions:

• Extracellular proteases critically regulate immune responses by modulating leukocyte chemoattractant activity.
• The activation of chemerin by serine proteases underscores the intricate interplay between proteolytic cascades and immune cell trafficking.
• Understanding these protease-chemoattractant interactions is vital for comprehending and potentially manipulating immune responses in various conditions.