Immunology Overview

Overview of Immunology

• Study of the immune system, which protects the body against pathogens, viruses, and other foreign substances
• Immunology involves understanding the mechanisms of immune responses, including innate and adaptive immunity

Innate Immunity

• First line of defense against infections
• Non-specific defense mechanisms that provide immediate protection
• Includes physical barriers (skin, mucous membranes), cellular responses (neutrophils, macrophages), and chemical responses (inflammatory responses)

Adaptive Immunity

• Specific immune response that develops over time
• Involves activation of immune cells (T cells, B cells) that recognize and respond to specific antigens
• Includes humoral immunity (antibody-mediated) and cell-mediated immunity

Immune Cells

• T Cells (T Lymphocytes)
  • Recognize and respond to antigens presented by antigen-presenting cells (APCs)
  • CD4+ T cells (helper T cells) coordinate immune responses, CD8+ T cells (cytotoxic T cells) kill infected cells
• B Cells (B Lymphocytes)
  • Produce antibodies to neutralize or remove pathogens
  • Activated by antigen binding and T cell help
• Dendritic Cells
  • APCs that present antigens to T cells
  • Activate immune responses by recognizing pathogens and presenting antigens

Antibodies (Immunoglobulins)

• Produced by B cells in response to antigens
• Recognize and bind to specific antigens, marking them for destruction
• Five classes: IgA, IgD, IgE, IgG, IgM

Immune Response

• Recognition
  • Antigens recognized by immune cells through pattern recognition receptors (PRRs) and antigen-presenting cells (APCs)
• Activation
  • Activation of immune cells, including T cells and B cells, through co-stimulatory signals and cytokines
• Effector Response
  • Elimination of pathogens through antibody-mediated and cell-mediated mechanisms
• Memory Response
  • Development of immunological memory, allowing for rapid response to future infections

Immunological Disorders

• Immunodeficiency Disorders
  • Weakened immune system, increasing susceptibility to infections (e.g., HIV/AIDS)
• Autoimmune Disorders
  • Immune system attacks self-antigens, leading to tissue damage (e.g., rheumatoid arthritis, lupus)
• Allergies
  • Overactive immune response to harmless substances, leading to inflammation and tissue damage

Overview of Immunology

• Immunology is the study of the immune system, which protects the body against pathogens, viruses, and other foreign substances
• It involves understanding the mechanisms of innate and adaptive immunity

Innate Immunity

• Provides immediate protection against infections through physical barriers, cellular responses, and chemical responses
• Includes skin and mucous membranes as physical barriers
• Cellular responses involve neutrophils and macrophages
• Inflammatory responses are a type of chemical response

Adaptive Immunity

• Develops over time and involves specific immune responses to specific antigens
• Involves activation of immune cells, including T cells and B cells
• Includes humoral immunity (antibody-mediated) and cell-mediated immunity
• T cells recognize and respond to antigens presented by antigen-presenting cells (APCs)

Immune Cells

• T Cells (T Lymphocytes)
  • Recognize antigens presented by antigen-presenting cells (APCs)
  • CD4+ T cells coordinate immune responses, while CD8+ T cells kill infected cells
• B Cells (B Lymphocytes)
  • Produce antibodies to neutralize or remove pathogens
  • Activated by antigen binding and T cell help
• Dendritic Cells
  • Present antigens to T cells, activating immune responses
  • Recognize pathogens and present antigens

Antibodies (Immunoglobulins)

• Produced by B cells in response to antigens
• Recognize and bind to specific antigens, marking them for destruction
• Five classes: IgA, IgD, IgE, IgG, IgM

Immune Response

• Recognition
  • Antigens recognized by immune cells through pattern recognition receptors (PRRs) and antigen-presenting cells (APCs)
• Activation
  • Activation of immune cells, including T cells and B cells, through co-stimulatory signals and cytokines
• Effector Response
  • Elimination of pathogens through antibody-mediated and cell-mediated mechanisms
• Memory Response
  • Development of immunological memory, allowing for rapid response to future infections

Immunological Disorders

• Immunodeficiency Disorders
  • Weakened immune system, increasing susceptibility to infections (e.g., HIV/AIDS)
• Autoimmune Disorders
  • Immune system attacks self-antigens, leading to tissue damage (e.g., rheumatoid arthritis, lupus)
• Allergies
  • Overactive immune response to harmless substances, leading to inflammation and tissue damage