How can you remove interfering cold agglutinins from a test sample?

Incubating the clot at 1°C-4°C for several hours, then removing the serum is effective for removing interfering cold agglutinins from a test sample because cold agglutinins react at lower temperatures, leading to the agglutination of red blood cells in the sample. By lowering the temperature to 1°C-4°C, these antibodies precipitate out of the solution. After sufficient incubation, the liquid portion (serum) can be carefully removed, leaving behind the agglutinins and any agglutinated cells. This ensures that the serum used for testing is free from cold-reactive antibodies, allowing for more accurate results in serological tests.

Using an anticoagulated sample does not directly address the presence of cold agglutinins, as it may still contain these antibodies unless treated properly. Centrifuging the serum and removing the top layer may not specifically target and remove cold agglutinins, as they could still remain in the serum. Heating the serum at 56°C can be useful for other types of antibody interference but is not effective for cold agglutinins, as these antibodies are typically not heat-sensitive and could remain in the sample even after heating.