Introduction to Immunology and Immunotherapeutics

Learning Objectives

• Understand the basic principles of human immunity and the roles of specific organs and cells in immune responses.

• Differentiate between innate and adaptive immune responses, including their molecular and genetic determinants.

• Explore immune system receptors, signaling pathways, and the functions of cytokines and chemokines.

• Analyze immunopathology related to infections, allergies, autoimmune diseases, and central nervous system disorders.

• Investigate experimental and pharmacological strategies targeting immune mechanisms and evolving diagnostic technologies.

Introduction to Immunology

What is Immunology?

• It comprises both molecular and cellular components.

• Functions can be categorized as non-specific and specific.

• Dysfunction in the immune system can lead to various diseases.

Key Terms in Immunology

• Pathogens often evade detection by the host's immune system.

• Antigen: A molecule capable of inducing an immune response in the host organism.

Historical Context

• His work led to the eventual worldwide eradication of smallpox, saving countless lives.

Immune System Overview

Branches of the Immune System

• Innate Immune System:

• Quick response (minutes to hours) and non-specific.

  • Recognizes patterns and repeating elements of pathogens.

  • Major functions include recognition, destruction, and inflammation.

• Adaptive Immune System:

• Slower response (days to weeks) and highly specific.

  • Distinct parts of pathogens are recognized, leading to memory formation.

Immune Cells and Their Functions

• Lymphocytes: Involved in adaptive immunity, with single antigen specificity.

• Myeloid Cells: Involved in innate immunity, with multi-antigen specificity.

Immune System Locations

• Central Immune Organs: Where leukocyte development occurs.

• Secondary Immune Organs: Where leukocyte function takes place, also known as the periphery.

Research Tools in Immunology

Knockout Mice

• Process of Creating Knockout Mice:

1. Generate modified DNA to replace the normal gene.

2. Use homologous recombination in embryonic stem cells.

3. Implant ES cells into a pseudo-pregnant female mouse.

4. Backcross to generate heterozygote and then knockout mice.

Advances in Gene Editing

• Allows direct modification of mouse RNA, significantly speeding up the process (from years to ~6 months).

• Enables simultaneous introduction of multiple mutations, though it has limitations such as off-target effects.

Contributions of Knockout Mice to Immunology

• B cell and T cell development, antigen presentation, and cytokine signaling.

• Models for human diseases such as cancer, autoimmunity, and metabolic disorders.