Complement and immune defense: from innate immunity to human diseases.

Area of Science:

• Immunology
• Infectious Diseases
• Autoimmunity

Background:

• The human body possesses a sophisticated immune defense to combat microbes and infectious agents.
• Immune responses are a double-edged sword, requiring a balance between attacking foreign invaders and protecting host tissues.
• Dysregulation of immune responses, such as the complement system, can lead to self-damage and disease.

Purpose of the Study:

• To explore the dual role of the immune system in host defense and potential self-harm.
• To investigate the significance of the complement system as a primary innate immunity defense line.
• To understand how dysregulation of the complement system contributes to various pathologies.

Main Methods:

• Review of the human immune system's recognition and elimination mechanisms for infectious agents.
• Analysis of the complement system's role in innate immunity and its regulatory pathways.
• Examination of immune escape strategies employed by pathogens.

Main Results:

• The immune system must balance attacking foreign entities with self-protection.
• The complement system, a key component of innate immunity, aids in eliminating microbes and altered self-cells.
• Defective regulation of the complement cascade can lead to infections, autoimmune diseases, and conditions like hemolytic uremic syndrome (HUS), dense deposit disease (DDD), and age-related macular degeneration.

Conclusions:

• Maintaining a tight balance in immune responses, especially the complement system, is vital for health.
• Dysregulation of the complement system is implicated in severe renal diseases, blindness, and autoimmune disorders.
• Understanding immune regulation is critical for developing therapeutic strategies against infectious and autoimmune diseases.