Term
Antigens & Antibodies
A) Terminology: |
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Definition
1) Antigen: immunogen, allergin & agglutination (Ag)
- Any substance that causes antibody formation
- Can be a microbe, foreign material, or "self"
- Usually proteins or large polysaccharide
2) Antibody: immunoglobulin, Ab, Ig
- Protein made in response to an antigen
- Recognize and bind to Ag |
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Term
Antigens & Antibodies
Antigen- Antibody Reaction: |
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Definition
- Ab will attach to the Ag at a specific site
- Valence- Number of Ag's that will attach to Ab |
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Term
Types of Acquired Immunity
A) Active: body makes own Ag |
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Definition
How are we exposed? - natrually or artifically
Natural Active:
- Come across the antigen natrually ex: cold, virus
Artifical Active:
- Antigen artifically introduced (vaccine)
- Vaccines: MMR, DPT or DTaP, HIB
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Term
Types of Acquired Immunity
B) Passive: Ab from an animal/human |
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Definition
1) Natural Passive:
- Ab goes from mother to infant
- Placental or colostrum (breast milk w/ Ab.)
2) Artifical Passive:
- Ab recieved via injection
- Examples- Antitoxins (antiserum) or Rhogam (anti-Rh specific)
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Term
Serum Immunoglobulins
A) Serum Electrophoresis: Gamma globulin portion of serum |
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Definition
1) IgA: γA Secretory Ab
- MW= 70,000 OR 400,000 Daltons
- Found in: mucous membranes, saliva, tears, clostrium & blood
- 1st and 3rd lines of defense
- 10-15% of total Ab in serum but % higher in total secretions
- Monomer in blood, Dimer in secretions
- Unique by: molecular weight |
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Term
Serum Immunoglobulins
A) Serum Electrophoresis: Gamma globulin portion of serum (cont.)
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Definition
2) IgD= γD
- MW= 180,000 D
- Internal marker on B lymphocytes
- 0.2% of total Ab
- Monomer
- Unique by: attaches to B cells |
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Term
Serum Immunoglobulins
A) Serum Electrophoresis: Gamma globulin portion of serum (cont.) |
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Definition
3) IgE: γE Allergic Ab
- MW= 200,000 D
- Invovled in hypersensitivity or allergic reactions
- 0.002% of total Ab
- Monomer
- Unique by: allergic react. & least abundant
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Term
Serum Immunoglobulins
A) Serum Electrophoresis: Gamma globulin portion of serum (cont.) |
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Definition
4) IgG: γG Circulatory Ab
- MW= 160,000 D
- Protects against microbes, triggers complement, & ↑ phagocytosis
- Crosses fetal-placental membrane
- 80% of total Ab - Monomer
- Unique by: Most abundant |
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Term
Serum Immunoglobulins
A) Serum Electrophoresis: Gamma globulin portion of serum (cont.) |
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Definition
5) IgM: γM Circulatory Ab
- MW= 900,000 D
- 1st Ab to arrive in response to initial exposure to Ag
- Does NOT cross the fetal-placental membrane
- 5-10% of total Ab
- Pentamer
- Unique by: largest MW |
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Term
Serum Immunoglobulins
B) Antibody Memory: anamnestic response |
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Definition
Intial: 4-7 days IgM, 10-17 days IgE
Secondary: 2-7 days IgG with a greater magnitude
*- Once seen unknown microbe/disease, body takes a while to make Ab
- Once exposed body saves recipe and will remember what to product to protect next time |
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Term
Serum Immunoglobulins
C) Antibody Structure of a Monomer: |
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Definition
4 polypeptide chains: 2 heavy & 2 light
Joined by: Disulfide bonds to form a Y shape
Arms of Y: Fab region
- Region where Ag binds
- Contains variable amino acid region
- Specific for- Ag
Stem of Y: Fe region (fragment of cell binding)
- Contains constant amino acid
- Binds to- Cells or compliment
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