A complement fixation test is done to see if a specimen contains antibodies to rubella virus. A control negative for antibodies and a control positive for antibodies are run, and the sensitized sheep cells are tested alone with no specimen or complement added. Which of reactions below is correct if the specimen does contain antibodies?

Question

Quizplus · Accepted Answer

In a complement fixation test, the presence of antibodies in the specimen leads to the fixation of complement and no lysis of sensitized sheep cells. Thus, for a specimen containing antibodies, there should be no lysis (similar to the positive control). The negative control, which lacks antibodies, allows for complement activation and lysis of sheep cells. The test of red cells alone without complement or specimen should not result in lysis, indicating the system's integrity without the specific reaction components.

A Complement Fixation Test Is Done to See If a Specimen