The Adaptive Immune Response

Flashcards covering key concepts and vocabulary related to the adaptive immune response.

Adaptive Immunity

Develops the most effective means to eliminate invaders, characterized by molecular specificity, immunological memory, and immune tolerance.

Lymphocytes

White blood cells that recognize foreign material (antigen) and proliferate to lead to adaptive immunity.

Cytotoxic T cells (Tc cells)

Induce apoptosis in 'self' cells that are infected with viruses or are otherwise corrupt.

Helper T cells (Th cells)

Direct and assist the immune response.

B lymphocytes (B cells)

Responsible for humoral immunity and programmed to produce antibodies.

T Cell Receptors (TCRs)

Molecules that only bind to antigens presented by the body's own cells.

B Cell Receptors (BCRs)

Membrane-anchored antibodies that bind free antigens.

Immune Tolerance

Prevents inappropriate adaptive immune responses from damaging the body’s own tissues.

Central Tolerance

Elimination of immature T and B cells that recognize 'self' molecules during lymphocyte maturation.

Peripheral Tolerance

Prevents mature T and B cells from reacting against self or harmless molecules that were not eliminated during central tolerance.

Clonal Selection

Process by which a naive B cell recognizes an antigen, becomes activated, and proliferates.

Immunogenic

Refers to the ability of an antigen to provoke an immune response.

Epitopes

Distinct regions of a molecule that are recognized by the adaptive immune system.

Major Histocompatibility Complex (MHC)

Molecules on cell surfaces that present antigens; MHC class I present endogenous antigens and MHC class II present exogenous antigens.

Antibody-dependent cellular cytotoxicity (ADCC)

Mechanism by which NK cells induce apoptosis in antibody-bound 'self' cells.

IgM

First antibody class made during the primary response; provides direct protection.

IgG

Most abundant antibody in blood; provides long-term protection and is transported across the placenta.

IgA

Most abundant class produced; provides mucosal immunity.

Class Switching

The process by which B cells change the class of antibody they produce.

Natural Killer (NK) Cells

Cells that induce apoptosis in antibody-bound 'self' cells and recognize host cells lacking MHC class I.