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Glite Dictionary
complement fixation

complement fixation

8.9
A lab test that shows whether blood has antibodies to a particular germ
  • noun
  • /ˈkɒmplɪmənt fɪkˈseɪʃən/
  • Specialized
translation icon : fijación del complemento
  • After analyzing the blood samples, the lab reported a significant complement fixation level in patients with autoimmune diseases.

Examples

  • Researchers found that complement fixation tests are crucial for diagnosing certain viral infections.

  • The references documented that since the Vietnam War, dengue has been diagnosed by hemagglutinin inhibition, plaque neutralization, complement fixation, and/or virus isolation.

    Academic text (2012)

  • The doctor explained that a low complement fixation result may indicate a weakened immune response.

Surface Forms

complement fixation singular
complement fixations plural

Morphology

complement + fixation

A learner who knows 'complement' (serum proteins) and 'fixation' (attaching) can plausibly infer that the phrase refers to complement proteins being 'fixed' or bound, so a general binding/attachment sense is derivable. However, the full immunological meaning (consumption of complement by antigen–antibody complexes and its functional consequences) is technical and not predictable at B1, so it is only partially transparent.

Etymology

Complement fixation comes from old lab tests where scientists mixed a germ part called an antigen with a person's blood to see if they would join. If they joined, they 'fixed' the complement, a group of small proteins, and that fixation meant the proteins were attached or used up and could not react again, so a 'fixed' complement showed that specific antibodies were present.