A SHORT QUIZ ON RADIOIMMUNOASSAY (RIA)

1. This technique measures the concentration of which substance?

2-4. In RIA, what are the three components that should be present for the test to be performed?

5. The concentration of the labeled antigen is (directly/ inversely) proportional to the natural antigen.

6-7. Who developed the RIA technique?

8. One of the developers of RIA received a Nobel Prize for what hormone?

9. What is the reagent or material used for labeling antigens?

10. More of the unlabeled antigens are binding to the antibodies when the unlabeled antigen's concentration is (increased/ decreased).



CASE STUDY

A 20 year old female noticed that there is a lump found on her throat. She also observed that she gained weight in the past weeks. Her hands felt cold and that she was always nervous. She went to the doctor and had her blood tested. Radioimmunoassay was the test performed. The results showed that she has hyperthyroidism.

• What is/are the hormones tested that confirmed the patient's condition?
• What are the expected results in the said condition?
• Are there other test/s that should be done for the confirmation of the patient's condition? Give a brief explanation.
  
• What other signs & symptoms seen in patients with hyperthyroidism?
• In your own words, state the principle of radioimmunoassay.

Reference:
WIKI-RIA

Radioimmunoassay (RIA)

Radioimmunoassay (RIA)

This technique which is very sensitive and is used to measure the concentrations of antigens. Radioimmunoassay technique is a specific and sensitive test, but this technique need a special equipment, which is costly. Substances used in this test are radioactive, so special precautions are to be observed.

Radioimmunoassay or RIA is one of the tests used to help the clinician determine the levels of hormones in a patient. Estrogen is one of these hormone. The level of estrogen is important to be measured because an increase or decrease of its level is unhealthy and may be detrimental to the patient.

Principle:

In this test, antigens which are of known amount or quantity are made radioactive. These antigens, which are now radioactive, are then mixed with antibodies of that antigens. Which result the two to bind chemically to one another. Then, a serum sample from a patient which contain an unknown amount or quantity of the same antigens is then added. This cause the unlabeled antigens from the patient's serum to compete with the radiolabeled antigens for binding sites in the antibody.

Reference:
Wikipedia-RIA