The Alpha2 Macroglobulin, Serum test is used to measure the level of the alpha-2 macroglobulin protein in the blood serum, which plays a role in immune functions and inflammation control. This test helps assess conditions such as liver diseases, chronic infections, and certain types of cancer. Normal values are typically between 150-350 mg/dL, and the patient may be asked to fast before the test to ensure accurate results.