Chapter 2 Immunity

Innate Immunity

The first line of defense against pathogens, present at birth, providing immediate, nonspecific responses.

Adaptive Immunity

Acquired immunity that targets specific antigens, typically slower to develop but provides memory for future protection.

T Lymphocytes

White blood cells that mature in the thymus and are responsible for cell-mediated immunity; includes Cytotoxic T cells and Helper T cells.

B Lymphocytes

White blood cells that develop in the bone marrow; they produce antibodies and have Memory B cells for faster responses upon re-exposure.

Memory Cells

Cells formed during the adaptive immune response that remain long-term to provide quicker responses to previously encountered antigens.

Primary Antibody Response

The initial immune response to an antigen, characterized by the production of antibodies after a lag period.

Secondary Antibody Response

The more rapid and robust immune response upon re-exposure to an antigen, due to the presence of Memory B cells.

Immunoglobulin Classes

There are five classes: IgA, IgD, IgE, IgG, and IgM, each with unique roles in the immune response.

Hypersensitivity Reactions

Exaggerated or inappropriate immune responses that cause tissue damage or disease, classified into four types.

Anaphylaxis

A severe, potentially life-threatening allergic reaction characterized by rapid onset of symptoms including hypotension and respiratory distress.

General Adaptation Syndrome (GAS)

A three-stage response (alarm, resistance, exhaustion) of the body to chronic stress.

Histamine

A chemical mediator released during inflammation that induces vasodilation and increases the permeability of blood vessels.

Autoimmunity

A condition where the immune system mistakenly attacks the body's own tissues.

Lupus (SLE)

A chronic autoimmune disease characterized by the production of autoantibodies and multisystem involvement.

HIV/AIDS

A viral infection that leads to immunodeficiency by destroying CD4+ T cells, increasing susceptibility to infections.

Antigen-Presenting Cells

Cells that process and present antigens to T lymphocytes, playing a crucial role in the activation of the adaptive immune response.

Complement Proteins

Proteins that enhance antibody action, playing roles in opsonization, promoting inflammation, and lysing pathogens.

Vaccines

Biological preparations that provide active immunity by exposing the immune system to harmless components of pathogens.

Innate Immunity

The first line of defense against pathogens, present at birth and lasting a lifetime.

Barriers of Innate Immunity

Includes skin, mucous membranes, and chemicals produced by the microbiome.

Inflammatory Response

Characterized by vasodilation, phagocytosis, and fibrinogen release.

Nonspecific Response

The same response regardless of the pathogen, with no immunological memory.

Cellular Components of Innate Immunity

Includes neutrophils, macrophages, and dendritic cells.

Key Substances in Innate Immunity

Includes pyrogens (fever-inducing substances), interferons (block viral replication), and complement proteins (enhance antibody action).