Indicators
The second most abundant immunoglobulin G (IgG) subclass in the circulation of healthy individuals. The IgG2 core hinge sequence contains 12 amino acids and up to four interchain disulfide bonds. This subtype has low affinity for binding both Fc receptors and complement component C1q. The production of this IgG2 is stimulated by exposure to bacterial capsular polysaccharides and other antigenic glycans.
Indicators
Along with the immunoglobulin G4 subclass (IgG4), the IgG3 subtype makes up a minor part of circulating antibodies in healthy individuals. The core hinge sequence contains approximately four times the number of amino acids as the other subclasses; allotypes of IgG3 can have up to 62 hinge residues and up to four interchain disulfide bonds. The increased hinge size for IgG3 increases the separation between the Fc (constant fragment) tail and Fab (antigen binding fragment) arms of antibodies of this subclass. This enhances the relative flexibility of the molecule, which may modulate antigen-binding capacity and immune complex formation, and may increase the affinity for binding to both Fc receptors and complement component C1q.
Indicators
Along with the immunoglobulin G3 subclass (IgG3), the IgG4 subtype makes up a minor part of circulating antibodies in healthy individuals. The IgG4 core hinge sequence contains 12 amino acids and two interchain disulfide bonds.This subtype has moderate affinity for binding Fc receptors and does not bind complement component C1q. The production of IgG4 can be stimulated following repeated or long-term exposure to antigen. Elevated levels are found in various diseases and infections and can be indicative of an fibroinflammatory syndrome known as IgG4-related disease.
Tests
A ketones in urine test measures ketone levels in your urine. Normally, the cells in your body use blood glucose (also called blood sugar) for energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your bloodstream. If your cells can't get enough glucose, your body breaks down fat for energy instead. This produces an acid called ketones, which can build up in your blood and urine.
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Tests
A lipase test measures the level of lipase in your blood. Lipase helps your body digest fats . It's a type of digestive enzyme. An enzyme is a protein that speeds up certain chemical reactions in your body. Most of your lipase is made in your pancreas, an organ located behind the lower part of your stomach. Lipase is also made in your salivary (spit) glands and in your stomach.
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Indicators
Direct molecular detection of Mycobacterium tuberculosis complex in respiratory specimens.
Glossary Term
A DNA polymer made up of a small number of nucleotides.
Pcr Terms
Tests
A pleural fluid analysis is a group of tests that examine a sample of abnormal fluid that builds up in the space between your lungs and chest wall. This space is called the pleural space.
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Article
Research record from JCO Precis Oncol, 2026-09-28. PMID 42804730.
Tests
This test measures the level of renin in your blood. Renin is an enzyme, a protein that speeds up certain chemical reactions in your body. It's made by your kidneys. When your blood pressure or sodium decreases or your potassium increases, your kidneys release renin. That's because renin also acts as a hormone (a chemical messenger in your bloodstream that controls the actions of certain cells or organs) to help control your blood pressure.
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Tests
A sputum culture is a test that checks for bacteria or another type of germ that may be causing a respiratory tract infection (an infection in your lungs or airways). Sputum, also known as phlegm, is a thick type of mucus made in your lungs. If you have an infection or chronic illness affecting the lungs or airways, sputum can settle in your lungs, and you may also cough it up
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Tests
A stool elastase test measures the amount of elastase in your stool (poop). Elastase is a type of digestive enzyme, a protein that speeds up certain chemical reactions in your body. The pancreas, a gland that sits behind your stomach, makes these digestive enzymes to help your body break down food and absorb nutrients. Your body can then use these nutrients for energy, growth, and repairing cells.
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