Phagocytosis

Phagocytosis

1. Stage 1 Chemotaxis

   • Bacteria invades Tissues
   • Attracted by chemical signals
   • Release of Interleukin-8
     • Neutrophils mobilize to infection

2. Stage 2 Opsonization

   • Neutrophilic attachment
   • Preparation for ingestion
     • Interaction of complement system
     • Or other Immunoglobulins

3. Stage 3 Ingestion

   • Ingestion by Neutrophil
   • Covered by Pseudopod Membranes

4. Stage 4 Killing

   • Neutrophilic release lytic elements
   • Respiratory Burst
     • Hydrogen Peroxide Production
       • Released for destruction
     • pH reduction
   • Neutrophil is destroyed

5. Neutrophils and Monocytes

   • Find and destroy bacteria

6. Bacteria Not Destroyed

   • Located in Secondary sites
   • Multiply and release toxins

7. Phagocytic Activivty

   • Work Together to Destroy
     • Phagocytic Cells
     • Complement System
     • Cytotoxins
     • Acute-phase reactants