Reviewed By: Pramod Kerkar, MD, FFARCSI

What is Immunoglobulin or Antibody?

Immunoglobulin is also known as antibody. There are 5 types of Immunoglobulin IgA, IgD, IgE, IgG and IGM. The 5 immunoglobulin also known as Game-globulin. Individuals suffering with liver infection, autoimmune diseases, arthritis, infection, allergies and blood disorders like multiple myeloma often shows increased level of one or more than one of these gamma globulin in blood serum. Immunoglobulin are mostly produced by plasma cells within bone marrow and blood stream. Immunoglobulin in smaller quantity is also produced by lymphocytes. Plasma cells are also known as B cells. Immunoglobulin protects endothelial cells of stomach, intestine, breathing passages like trachea, bronchi and lung as well as kidney and liver cells from attack of bacterial, protozoal and viruses during infection. The immunoglobulin is a part of our immune system. Immune system consists of white blood cells, T lymphocytes, compliments protein molecules and immunoglobulin. Immunoglobulin pairs with microscopic protein molecules spread over outer surface of viruses and bacteria known as antigen. The pairing of immunoglobulin IgM and IgG with antigen protein that is spread over the outer surface of bacteria and viruses activates microphages. Macrophages destroys the viruses and bacteria once it identifies the antigen and antibody pairing over the outer surface of virus and bacteria.

Immunoglobulin or antibody also pairs with certain protein on the surface of normal human mucosal endothelial cell linings of stomach, intestine, trachea, bronchi and lungs. Such pairing protects endothelial cells from attack of viruses and bacteria, and prevents cell damage. The similar complex protective protein pairing of antigen and antibody is also observed with mucosal endothelial cells of ureter, kidney, urinary bladder and urethra.

What is Immunoglobulin or Antibody?

The question then asked is “What is Immunoglobulin?”.

Immunoglobulin are microscopic protein molecules that floats in blood and lymphatic fluid. Immunoglobulin Ig M and IgG are most common antibody protein molecule in blood serum and lymphatics. IgG and IgM immunoglobulin during early and later phase of infection adheres to microscopic protein molecule known as antigen that lies over outer surface of viruses, bacteria and fungi during infection. The immunoglobulin IgG and IgM pairing with antigen protein molecule of viruses, bacteria and fungi attracts macrophages that eventually kills these pathogens.

IgA Immunoglobulin or antibody

IgA immunoglobulin or antibody1 is secreted by the plasma cells and often discharged in mucous secretion of stomach, intestine, trachea and bronchi. Thus immunoglobulin or antibody A is found in mucosal secretion of stomach, intestine and respiratory tract. The immunoglobulin IgA protects intestinal endothelial cell lining from viral and bacterial infection. IgA immunoglobulin is also found in tears, salivary secretions, sweat, urine, prostate secretion and vaginal discharge. In blood serum of normal individual 5 to 15% of immunoglobulin represents IgA immunoglobulin.

IgD Immunoglobulin or antibody

IgD Immunoglobulin or antibody2 is often observed in trace amount in blood serum in most normal individual. IgD Immunoglobulin or antibody represents less than 1% of Gama-globulin or total serum immunoglobulin. The IgD immunoglobulin concentration is higher than 1% in patients suffering with multiple myeloma3. The increased number of molecules of IgD Immunoglobulin or antibody representing more than 1% is considered diagnostic in diagnosis of multiple myeloma and amyloidosis. The blood concentration of IgD immunoglobulin or antibody is higher than Immunoglobulin IgE in normal individual blood serum.

IgE Immunoglobulin- or antibody

The IgE immunoglobulin or antibody4 is Y shape antibody protein molecule. Traces of IgE antibody is observed in normal individual. The amount seen in blood serum is of lower number (less than 1% of total immunoglobulin) compared to Immunoglobulin IgG and IgM. IgE concentration increases during various parasite infection like malaria and amoebiasis. IgE immunoglobulin or antibody is also increases during allergic reaction like rash, hives, asthma causes by pollens, food allergies or bee stings. Thus, IgE immunoglobulin or antibody concentration is increased during symptoms of allergies.

IgG Immunoglobulin or antibody

Serum antibodies are also known as Gama-globulin. IgG antibodies are the most common type of antibody and represents 70% to 80% of the total antibodies or Gama-globulin.. IgG immunoglobulin is also produced by plasma cells. The concentration of IgG immunoglobulin is always high after infection. Immediately following infection serum level of IgM immunoglobulin substantially increases and after 1 or 2 weeks the level of IgM immunoglobulin decreases and IgG immunoglobulin level increases. The blood serum level of IgG immunoglobulin remains high for several weeks after infection is treated and symptoms are relieved. IgG immunoglobulin helps to restrain activities and multiplication of viruses, bacteria and parasites. Such activities are achieved by pairing with antigen and formation of compliments. Compliments are inactive protein molecules form by liver and floats in blood serum as well as lymphatic fluid. IgG immunoglobulin during infection phase activates compliment. Active compliment triggers antigen antibody pairing and also makes fungi, viruses and bacteria sensitive to be engulf by macrophages. IgG immunoglobulin braces toxins and neutralizes its toxic character.

IgM Immunoglobulin or antibody

IgM is the largest sized immunoglobulin protein molecule among gamma globulin. Among 5 blood serum Gama-globulin IgM represent 5 to 10% in normal individual. IgM Immunoglobulin or antibody is produced as soon as individual is exposed to infection. Plasma cells begins production of IgM as soon as plasma cell is exposed to viruses and bacteria. IgM Immunoglobulin or antibody stimulates macrophages (white blood cells) to destroy the virus and bacteria during the initial phase of infection. IgM Immunoglobulin or antibody are released in blood serum and lymphatic fluid after production by plasma cells. IgM Immunoglobulin or antibody compromises bacteria and viruses once it adheres to protein molecule known as antigen that lies over its outer surface. IgM Immunoglobulin level is also elevated in certain diseases like macroglobulinemia, systemic amyloidosis, monoclonal gammopathy and autoimmune disease5.

Immunoglobulin along with B and T lymphocytes as well as compliments forms a defensive system within our body known as immune system. The normal immunity helps to prevent as well as compromise the infection and chronic diseases. The abnormal conditions resulting in low immunoglobulin causes increased incident of infection and infection often not responding to treatment. High level of blood serum immunoglobulin causes diseases like multiple myeloma or amyloidosis that often causes destruction of bones and soft tissue. We hope our immune response during adverse condition is normal. Normal immune response indicates normal blood level of IgA, IgD, IgE, IgG and IgM immunoglobulin. The normal response also causes increased concentration of one or more than one of 5 immunoglobulin when there is infection, inflammation, allergies or ingestion of toxins.

Also Read:

References

  1. IgA function – variations on a theme Jenny M Woof* and Michael A Kerr, A. Immunology. 2004 Oct; 113(2): 175–177.

  2. The Function and Regulation of Immunoglobulin Kang Chen1 and Andrea Cerutti 1,2, Curr Opin Immunol. 2011 Jun; 23(3): 345–352.

  3. Immunoglobulin D multiple myeloma: Presenting features, response to therapy, and survival in a series of 53 cases.

    Blade J, Kyle RA, J Clin Oncol 1994;12(11):2398-2404

  4. Immunoglobulin E in health and disease M. Amarasekera, Asia Pac Allergy. 2011 Apr; 1(1): 12–15.
  5. IgM predominance in autoimmune disease: genetics and gender. Duarte-Rey C1, Bogdanos DP, Leung PS, Anaya JM, Gershwin ME., Autoimmun Rev. 2012 May;11(6-7):A404-12.
Pramod Kerkar

Written, Edited or Reviewed By:

, MD,FFARCSI

Pain Assist Inc.

Last Modified On: March 13, 2018

This article does not provide medical advice. See disclaimer

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