Immunoglobulin G (IgG)

Immunoglobulins are a group of proteins (albumen) formed in plasma cells that specifically bind as antibodies with foreign substances (antigens) to render them harmless. The following classes of immunoglobulins can be distinguished:

  • Immunoglobulin A (IgA) – secreted on all mucous membranes of the respiratory tract, eyes, gastrointestinal tract, genitourinary tract, and via special glands around the nipple of mothers, where it protects against pathogens; found in blood serum and body secretions.
  • Immunoglobulin D (IgD) – occurs in the membrane of B lymphocytes.
  • Immunoglobulin E (IgE) – mediates protection against parasites, such as worms. Upon antigen contact, it leads to the release of histamines, granzymes, etc.; found in the membrane of mast cells and basophilic granulocytes (allergic immediate reaction).
  • Immunoglobulin G (IgG) – is formed only in a delayed defense phase (3 weeks) and remains for a long time. Detection of Ig G indicates a passed infection or vaccination; occurrence in blood serum and breast milk; placental.
  • Immunoglobulin M (IgM) – is the first class of antibodies formed on initial contact with antigens and indicates the acute infectious phase of a disease; occurrence in blood serum.

Immunoglobulins are composed of two light and two heavy polypeptide chains connected by disulfide bridges. The IgG is the antibody in the secondary immune response, that is, it becomes active when there has been an infection with a pathogen already known to the immune system. In addition, it is also involved in the mucosal barrier.

The process

Material needed

  • Blood serum

Preparation of the patient

  • Not necessary

Disruptive factors

  • Not known

Standard values

Age Normal value in mg/dl Normal value in IU/ml
Newborn 660-1.750 75,9-201,25
1st month of life 390-1.050 44,85-120,75
2nd month of life 250-680 28,75-78,2
3rd month of life 200-550 23-63,25
4th month of life 200-540 23-62,1
5. month of life 220-600 25,3-69
6th month of life 260-690 29,9-79,35
7th month of life 290-770 33,35-88,55
8th month of life 320-840 36,8-96,6
9th month of life 330-880 37,95-101,2
10th month of life 350-910 40,25-104,65
11th month of life 350-930 40,25-106,95
1 year 360-950 41,4-109,25
2 years 470-1.230 54,05-141,45
4 years 540-1.340 62,1-154,1
6 years 590-1.430 67,85-164,45
8 years 630-1.500 72,45-172,5
10 years 670-1.530 77,05-175,95
12 years 700-1.550 80,5-178,25
14 years 710-1.560 81,65-179,4
16 years 720-1.560 82,8-179,4
18 years 730-1.550 83,95-178,25
> 18 years 700-1.600 80,5-184

Indications

  • Suspected chronic infections
  • Suspicion of plasmocytoma (multiple myeloma).

Interpretation

Interpretation of increased values

  • Autoimmune diseases, unspecified
  • Chronic hepatitis (inflammation of the liver)
  • Chronic infections
  • Cirrhosis of the liverconnective tissue remodeling of the liver that leads to functional limitations.
  • Plasmocytoma (multiple myeloma)
  • Rheumatoid arthritis
  • Tumors, unspecified