13. Immunglobulins
• Immunoglobulins, also known as Antibodies,
are glycoprotein molecules produced by plasma
cells. They act as a critical part of the immune
response by specifically recognizing and binding
to particular antigens, such as bacteria or
viruses, and aiding in their destruction
• Types : soluble antibodies and membrane-
bound antibodies
• IgA
• IgD
• IgE
• IgG
• IgM
14. Ig A
• Exists in serum (1-4 mg/ml)
• Monomeric and Dimeric forms
• comprising approximately 15% of the total serum Ig.
• Secretory IgA, a dimer, provides the primary defense
mechanism against some local infections because of its
abundance in mucosal secretions (e.g., saliva and tears).
• The principal function of secretory IgA may be not to destroy
antigens but to prevent passage of foreign substances into the
circulatory system.
• IgA is a very weak complement-activating antibody; hence, it
does not induce bacterial cell lysis via the complement system.
• IgA is predominantly found on epithelial cell surfaces where it
acts as a neutralizing antibody.
15. Ig E
• Molecular weight: 200,000
• H-chain type (MW): epsilon (73,000)
• Serum concentration: 10 to 400 ng/mL
• Percent of total immunoglobulin: 0.002%
• Glycosylation (by weight): 12%
• Distribution: basophils and mast cells in
saliva and nasal secretions
• Function: protect against parasites
16. Ig D
• Molecular weight: 180,000
• H-chain type (MW): delta (70,000)
• Serum concentration: 0 to 0.4 mg/mL
• Percent of total immunoglobulin: 0.2%
• Glycosylation (by weight): 13%
• Distribution: lymphocyte surface
• Function: Innate and adaptive Immune
responses can be activated via membrane-
anchored IgD
17. Ig G
• Molecular weight: 150,000
• H-chain type (MW): gamma (53,000)
• Serum concentration: 10 to 16 mg/mL
• Percent of total immunoglobulin: 75%
• Glycosylation (by weight): 3%
• Distribution: intra- and extravascular
• Function: secondary response
18. Ig M
• Molecular weight: 900,000
• a pentamer where all heavy chains are identical
and all light chains are identical
• IgM is the first antibody built during an immune
response.
• IgM is predominantly found in the lymph fluid and
blood and is a very effective neutralizing agent in
the early stages of disease.
• Serum concentration: 0.5 to 2 mg/mL
• Percent of total immunoglobulin: 10%
• Glycosylation (by weight): 12%
• Distribution: mostly intravascular
• Function: primary response
19.
20. Immunomodulators
• A substance that stimulates or suppresses the
immune system and may help the body fight
cancer, infection, or other diseases. Specific
immune system modulators, such as monoclonal
antibodies, cytokines, and vaccines, affect specific
parts of the immune system.
21. Cytokines
• Cytokines are small proteins that are crucial in
controlling the growth and activity of other immune
system cells and blood cells. When released, they signal
the immune system to do its job. Cytokines affect the
growth of all blood cells and other cells that help the
body's immune and inflammation responses.
• One specific type of cytokine is called a chemokine. A
chemokine can make immune cells move toward a
target. There are different kinds of chemokines,
including interleukins, interferons, tumor necrosis
factors, and growth factors.
• The most common ones are interleukins and
interferons.
