Immune system dieases and trasnplant rejection

Immunological surveillance

The immune system's recognition and destruction of abnormal cells such as cancer cells.

Tumor antigens

Novel cell-surface components displayed by cancer cells on MHC I.

NK cells and cancer

Natural killer cells commonly perform immunological surveillance by detecting abnormal cells.

Transplant rejection

An immune response in which T cells attack transplanted tissue because they recognize its MHC I/antigen complexes as foreign.

Reducing transplant rejection

Donor and recipient MHC I/antigen characteristics can be matched to reduce rejection.

Immunodeficiency

A condition in which the immune system fails to respond adequately to foreign invasion.

Congenital immunodeficiency

Immunodeficiency present at birth.

Acquired immunodeficiency

Immunodeficiency that develops after birth.

Severe Combined Immunodeficiency (SCID)

A condition in which both antibody-mediated and cell-mediated immunity are impaired.

Anaphylactic shock

A systemic immune reaction in which large amounts of chemicals enter the blood, causing widespread vasodilation and fluid buildup in interstitial spaces.

AIDS

Acquired Immunodeficiency Syndrome resulting from HIV infection.

HIV

Human Immunodeficiency Virus, which destroys Helper T cells.

HIV effect on adaptive immunity

Destruction of Helper T cells prevents proper activation of B and T cells.

Infectious mononucleosis

A contagious disease in which B cells become enlarged and dysfunctional.

Systemic lupus erythematosus (SLE)

A chronic autoimmune inflammatory disease characterized by periods of active disease and remission.

Autoimmune disease

A condition involving an inappropriate immune response against the body's own tissues.

Type I hypersensitivity

Immediate hypersensitivity involving IgE antibodies and mast cell histamine release.

Type I timing

Occurs within seconds to minutes.

Type I examples

Asthma and anaphylaxis.

Type II hypersensitivity

Cytotoxic hypersensitivity involving IgG and IgM antibodies attacking antigens on specific cells.

Type II timing

Occurs within minutes to hours.

Type II example

Hemolytic transfusion reactions, commonly associated with ABO incompatibility.

Type III hypersensitivity

Immune complex-mediated hypersensitivity in which antigen-antibody complexes deposit in tissues and trigger inflammation.

Type III timing

Occurs over hours to days.

Type III examples

SLE and rheumatoid arthritis.

Type IV hypersensitivity

Cell-mediated delayed hypersensitivity involving T cells rather than antibodies.

Type IV timing

Delayed approximately 12–72 hours.

Type IV examples

Poison ivy, chronic rashes, and transplant rejection