Immunoblot for Immunoglobulin G (IgG) Subclasses (A, D, E, G) with Serum
This test measures the levels of different types of Immunoglobulin G (IgG) antibodies in your blood. IgG is the most common antibody in the body and plays a key role in fighting infections.
["Understanding your IgG subclass levels can help identify immune system function or deficiencies."]
Key facts at a glance
- LOINC
- 82995-2
- Short code
- TIF1-gamma IgG Ser Ql Line blot
- Synonyms
- TIF1-gamma IgG Ser Ql Line blot
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- line-blot
- CPT
- 82784
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Does This Test Measure?
IgG antibodies are divided into four subclasses (IgG1, IgG2, IgG3, IgG4) that have slightly different roles in immunity. This test detects the presence and relative amounts of each subclass in your serum using a technique called immunoblotting. This helps assess how your immune system is producing these antibodies.
Why Might You Need This Test?
Doctors may order this test if you have symptoms of immune system issues, such as frequent infections, autoimmune diseases, or if you’re being evaluated for conditions like hypogammaglobulinemia (low antibody levels) or certain immune deficiencies.
Sample Collection and Preparation
A blood sample is drawn from a vein in your arm. The blood is processed to separate the serum (the liquid part without clots) for testing. This serum is then analyzed using a technique called immunoblotting to detect IgG subclasses.
What to Expect Before the Test
There are no special preparations needed for this test. You may have some mild discomfort from the needle, but it usually goes away quickly. If you’re on blood-thinning medication, let your doctor know before the test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal IgG subclass levels can indicate underlying immune system problems. For example, low levels of certain subclasses may suggest an immune deficiency, while high levels might be seen in chronic infections, autoimmune diseases, or certain cancers. This test helps guide treatment decisions and monitor immune function over time.
Short name
IgG subclass serum profile (electrophoresis)
Frequently asked questions
What does an abnormal result mean?
How long does it take to get results?
Can I eat or drink before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy