Complement control protein factor H: the good, the bad, and the inadequate

Area of Science:

• Immunology
• Complement System
• Innate Immunity

Background:

• The complement system is vital for innate immunity, pathogen clearance, and linking innate and adaptive immunity.
• Complement regulators, like factor H, prevent unintended complement-mediated damage to host cells.
• Factor H controls the alternative pathway on blood and cell surfaces, requiring recognition of self-markers and C3b/C3d.

Purpose of the Study:

• To review the versatile recognition properties of complement factor H.
• To explore how factor H distinguishes between host cells, pathogens, and altered self-cells.

Main Methods:

• Literature review of current knowledge on complement factor H.
• Analysis of factor H's recognition mechanisms and their implications.

Main Results:

• Factor H mutations/polymorphisms impairing self-cell recognition are linked to complement-mediated diseases.
• Pathogens and cancer cells exploit factor H recognition as an immune evasion strategy.
• Factor H exhibits versatile recognition capabilities essential for immune homeostasis and defense.

Conclusions:

• Factor H's dual role in self-recognition and pathogen/altered-cell recognition is critical.
• Dysfunctional factor H recognition contributes to various diseases.
• Understanding factor H's recognition properties is key for therapeutic strategies.