Table 3

Host defences against respiratory infections

• Anatomical barriers
• Angulation of airways
• Mucociliary clearance
• Secretory IgA
• Surfactant
• Opsonising IgG, fibronectin
• Complement
• Alveolar macrophages
• Polymorphonuclear leucocytes
• Plasma components
• Vasoactive mediators
  • Based on Reynolds and Elias.36