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Updated: Jun 27, 2026

Measuring the 50% Haemolytic Complement (CH50) Activity of Serum
Published on: March 29, 2010
The serum complement system: a simplified laboratory exercise to measure the activity of an important component of
Jordan E Inglis1, Kimberly A Radziwon, Gregory D Maniero
1Biology Department, Stonehill College, Easton, MA 02357, USA.
Abstract:
The immune system is a vital physiological component that affords animals protection from disease and is composed of innate and adaptive mechanisms that rely on cellular and dissolved components. The serum complement system is a series of dissolved proteins that protect against a variety of pathogens. The activity of complement in serum can be determined by its ability to lyse red blood cells in vitro. Here, we describe a modification of a standard complement hemolysis assay that makes an interesting and informative laboratory exercise suitable for a variety of courses including physiology.
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