Immune system

Interferons

proteins produced by cells infected with a virus, diffuse to nearby cells to make a protein that interferes with viral production.

Complement Proteins

plasma proteins, become active and stimulate the following:

* chemotaxis - attracts phagocytes to pathogens
* opsinization - bind to pathogens so they become engulfed
* Inflammation - lysis, create pores in the bacterial membranes

3 ways cytotoxic t-cells kill antigens

1 - rupture the cell with perforin

2 - secrete a posion (lymphotoxin)

3 - activate genes (tell it to die - apoptosis - programmed cell death)

IgG

Largest, most diverse. 80% found in plasma tissue fluids. Resistance to viruses, bacteria, toxins.

IgE

attach to basophils and mast cells. inflammation and allergic reactions. appears in exocrine glands along with IgA.

IgD

Found on b-cells, antigen receptor, important in activating b cells

IgM

Make up 6%. The first to be secreted, they form a large complex of 5 antibodies - starburst pattern

IgA

13% found in singles or in pairs end up on epithelial surfaces. (found in breast milk, tears, nasal fluid, gastric juice, bile, urine)

Type 1 Allergic reaction

immediate response, activates b-cells directly, B-cells produce IgE that trigger basophils and mast cells. Chemicals are produced (histamines, prostaglandins, leukocytes)

Type 2 allergic reaction

antibody dependent cytotoxic reaction, allergen bonds to cell, phagocytosis and lysis of antigen occurs,

Allergens

Antigens that initiate allergic reactions. either sensitising lymphocytes or combining with antibodies.

Type 3 allergic reaction

immune complex reactions - large amounts of antigen antibody complexes block small vessels. This can damage tissues.

Type 4 allergic reaction

Delayed reaction allergy - repeated exposure to chemicals on the surface of the skin, T-cells become activated - 48 hour delay in response.

B lymphocytes respond to a foreign protein by?

phgocytosis

chemicals that target specific bacteria and fungi inside the body and prevent them from reproducing are?

antibiotics

A normal immune system response requires the presence of?

both T and B cells

T-lymphocytes are responsible for?

Producing antibodies

The type of immunoglobulin found in exocrine secretion glands is?

IgA

A substance that can Stimulate a primary repsonse but is unable to produce symptoms of a disease is?

A vaccine

agents that enter the body and cause disease are?

pathogens

The bodies non-specific defenses include?

Inflammation, Skin, complement, interferon,

All of the various macrophages are derived from?

monocytes

innate defense mechanisms act --- than defensive responses

more rapidly

interferon is a group of proteins produced by a cell in response to the presence of ?

viruses