Pharmacy Science Unit 5: Immunology and Microbiology

Learning Objectives

• Understand roles of microorganisms in infections and immune responses.
• Describe antimicrobial agents and vaccines for infection prevention.
• Grasp human pathology principles, including cancer, for patient interactions.

Types of Immunity

• Innate Immunity: Non-specific defenses; includes:

  • Passive: Physical and chemical barriers (e.g., skin, mucous).
  • Active:
    • Humoral (complements and blood proteins).
    • Cellular (phagocytes and NK cells).

• Adaptive Immunity: Specific defenses; characterized by:

  • Humoral (antibodies).
  • Cellular (T-cells).

Key Characteristics of Immunity

• Innate Immunity:

  • Inborn, older in evolutionary terms.
  • Non-specific; provides initial defense.
  • Rapidly deployed (immediate response).
  • Non-adaptive; does not improve with repeated exposure.

• Adaptive Immunity:

  • Acquired after exposure, relatively newer.
  • Highly specific to pathogens causing infection.
  • Requires 3-7 days to activate.
  • Adaptive; increases response with repeated exposure (memory).

Immune Response and Components

• Innate Immune System:

  • Cells: Macrophages, neutrophils, eosinophils, NK cells.
  • Mechanisms: Phagocytosis, cytokine release, and opsonization.

• Adaptive Immune System:

  • Cells: T-lymphocytes and B-lymphocytes.
  • Mechanisms: Antigen recognition and specific immune activation.

Cytokines

• Chemical messengers that coordinate immune responses.
• Released from both innate and adaptive immune cells.

Pathogen Recognition and Response

• Pathogen-Associated Molecular Patterns (PAMPs):
  • Recognized by Pattern Recognition Receptors (PRRs) on immune cell surfaces.
  • Examples include peptidoglycan (G+ bacteria) and lipopolysaccharide (G- bacteria).

Immune Evasion and Infection

• Microorganisms capable of evading innate immunity can multiply and cause disease.
• Activation of adaptive immunity occurs as innate response escalates.

Memory Cells and Antigen Recognition

• Adaptive immunity has "memory," enhancing responses upon subsequent exposures.
• A diverse range of B and T cells exists, but only a small portion is activated by specific antigens.

White Blood Cells (WBCs) Overview

• WBCs are crucial for the immune response, classified by:
  • Polymorphonuclear cells: Including neutrophils (50-70%), eosinophils (2-4%), and basophils.
  • Monocytes: Make up 2-8% of WBCs.
  • Lymphocytes: Comprising about 20-30% (includes T and B cells).

Overall Importance of Innate Immunity

• Innate immunity is essential for survival, often preventing infections.
• Many lower species thrive without adaptive immunity, but humans require functional innate immunity, particularly phagocytes.

Pre-reading material for PHA4011E Unit 5, covering immunology, microbiology, and pathophysiology in pharmacy science. Required references for the School of Pharmacy and Medical Sciences.