Adaptive Immunity

Adaptive immunity

the acquired ability to recognize and destroy a particular pathogen or its products

Antigen

elicits adaptive immune response; reacts with antibodies and T-cell receptors (TRCs)

Antigen presenting cells (APCs)

• engulf, process, and present antigens to lymphocytes (B and T cells)

• Macrophages and dendritic cells

• TCRs interact with APCs

T cell-mediated immunity

T cells

• T-helper (Th) cells

• Cytotoxic T (Tc) cells

T-helper cells

• Interacts with MHC II complexes

• enhance inflammation

Cytotoxic T cells

recognize antigen presented by MHC I protein on an infected cell

B cells

• interact with antigens

• present antigen to T cells

• specific

Antibodies

are soluble proteins made by B cells in response to exposure to non-self antigens

Antibody - mediated immunity

Antibody classes

• differentiated by amino acid sequence

• each antibody has a specific function

• IgG and IgM are found in blood

IgM

• primary response to exposure

• slow response

• low titer

IgG

• secondary response to exposure

• fast response

• high titer

Specificity

lymphocytes have surface receptors that interact with specific antigens

Memory

the ability to have a faster and stronger immunity due to subsequent exposure to the same antigen

Self Tolerance

adaptive immunity not being able to attack self-antigens

Natural immunity

receiving antibody directly from nature (ex: infection, genes)

Artificial immunity

artificially receiving the antibody (ex: vaccines, antivenom)

Active immunity

something causes our body produces the antibody

Passive immunity

receives antibody directly