Chapter 18 Bio 308 Steiner

Front 1

Dendritic cells

Back 1

(DCs) are immune cells and form part of the mammalian immune system. Their main function is to process antigen material and present it on the surface to other cells of the immune system, thus functioning as antigen presenting cells. They are located mainly on skin and the inner lining of t he nose, lungs stomach and intestines.

Front 2

Leukotrienes

Back 2

prolonged bronchial smooth muscle contraction, increased capillary permeability, edema

Singular is a leukotriene inhibitor

Front 3

Prostaglandin D2

Back 3

Minute blood clots, bronchial smooth muscle contraction, capillary dialiation

Front 4

Immunodeficiency

Back 4

the immune system responds inadequately to an antigen, either because of inborn or acquired defects in B cells or T cells. The weak response can leave an individual susceptible to infections, which can be severe.

1) Primary
2) Secondary

Front 5

Genetic factors in allergies

Back 5

High levels of IgE in families appears to predispose individuals to allergies and thereby has a genetic basis.

Front 6

Cell mediated or delayed type hypersensitivity

Back 6

typically take 12 or more hours to develop. These reactions are mediated by TH1 cells (sometimes called a delayed hypersensitivity T [TDH] cell)-- not by antibodies.

Front 7

Contact dermatitis (Cell mediated Disorder)

Back 7

occurs in sensitized individuals on second or subsequent exposure to allergens such as oils from poison ivy, rubber, certain metals, dyes soaps, cosmetics, some plastics, topical medications, and other substances.

Front 8

Tuberculin hypersensitivity (cell mediated disorder)

Back 8

tuberculin activates TH1 cells, which in turn release cytokines that cause large numbers of lymphocytes, monocytes, and macrophages to infiltrate the dermis. In a tuberculin skin test, purified protein derivative (PPD) from Mycobacterium tuberculosis is injected subcutaneously. A positive test is the formation of an induration within 48 hours. The diameter and elevation of the induration, indicate whether further Tests are needed.

Front 9

Granulomatous hypersensitivity

Back 9

the most serious of the cell-mediated hypersensitivities and usually occurs when macrophages have engulfed pathogens but have failed to kill them. TH1 cells sensitized to an antigen of the pathogen elicit the hypersensitivity reaction, attracting several cell types to the skin or lung. A granuloma in the skin (leproma) or lung (tubercle) develops.

Front 10

Autoimmune Disorders-

Back 10

occur when individuals become hypersensitive to specific antigens on cells or tissues of their own bodies despite mechanisms that ordinarily create tolerance to those self antigens. The antigens elicit an immune response in which auto-antibodies, antibodies against ones own tissues, are produced. An autoimmune response can be T-cell-mediated as well as against antibodies. These disorders are characterized by cell destruction in various types of hypersensitivity reactions.

Front 11

Myasthenia gravis (autoimmune disorder)

Back 11

This disorder involves a loss of acetylcholine receptors from the neuromuscular junction.


IgG antibodies are produced against the acetylcholine receptors markedly reducing their numbers.

Front 12

Rheumatoid arthritis (autoimmune disorder)

Back 12

Causes swelling in the joints and is a result of histamine release. Inflamation is result of IgG and IgM complex which is formed in the joints. Damages cartilage.

Front 13

Systemic lupus erythromatosus (SLE)

Back 13

Autoimmune complexes are deposited between the dermis and epidermis. Result of IgG, IgM, and IgA. Antibodies are made against the remnants of DNA of dead cells (all cells eventually die in body)

Much more common in women than in men.

Front 14

Transplant rejection

Back 14

is due to the destruction of the grafted tissue by the recipient’s immune system. This process, which depends on T cells, also accounts for rejection of most organ transplants in humans. Transplants recognized as nonself are rejected.

A combination of both cell-mediated and humoral immune reactions is responsible for transplant rejection. TH1 (inflammatory T) cells activate macrophages, which produce inflammatory mediators. TH2 cells trigger both Tc and B cell activation. B cell activation leads to the production of plasma cells that synthesize antibodies, including anti-HLA-DR. Inflammatory mediators, Tc cell-mediated toxicity, and antibodies, along with complement, bring about transplant rejection

Front 15

Immnosupression

Back 15

Radiation (X-rays) of lymphoid tissue suppresses the immune system as do cytotoxic drugs, such as azothioprine, and methotrexate. Radiation and cytotoxic drugs can kill T cell responses to infections and also affects B cells.

Front 16

Tacrolimus

Back 16

Immunosuppression with tacrolimus was associated with a significantly lower rate of acute rejection compared with cyclosporin-based immunosuppression (30.7% vs 46.4%) in one study.