The CH50 method is used as a screening test (for the measurement of total classical complement activity) when assessing the ability of an individual to fight infection.

The measurement of complement CH50 activity is now recommended as part of the diagnostic protocol for Primary Immunodeficiency ^1,2 and it can also provide important information for many other disease states such as Systemic Lupus Erythematosus and bacterial infections.³

CH50 measures the lysis of antibody-sensitised sheep erythrocytes after addition of fresh serum. The result is expressed as the reciprocal of the dilution that yields 50% erythrocyte (red blood cell) lysis. In comparison the CH100, or total haemolytic complement, is a measurement of 100% lysis of the red blood cells.

The AH50 (or AH100) is used to detect a deficiency of the alternative complement pathway.

This assay has been developed to measure total complement activity (CH50), by directly testing the function of the resulting end product of the complement cascade, the Membrane Attack Complex (MAC). Measurement of total complement activity (CH50) is recommended in Primary Immunodeficiency guidelines and provides important additional information for many other disease states and infections.

Other assays are available on the Binding Site SPAplus

• Terminal Complement Complexes which occur naturally during sample handling are recognised by the CH50 Eq ELISA 

• No requirement for red blood cells and therefore not subject to seasonal variation and shelf-life limitations 

• Good correlation with gold standard methods⁴ 

• Results are reported directly in CH50 Eq units by plotting a simple linear graph 

• CH50 Eq ELISA is provided as a complete kit which can be automated for ease of use 

• Once activated, samples can be stored frozen at -20°C to allow batch testing

Total Haemolytic Complement (THC) and Alternative Pathway Haemolytic Complement (APHC) kits are effective screening assays to aid in the identification of complement deficiency.

The Total Haemolytic Complement kit is primarily designed to detect deficiencies of the Classical Complement Pathway and the terminal sequence (C3-C9) components, whereas the Alternative Pathway Haemolytic Complement kit is designed to measure the activity of the Alternative Complement Pathway. 

• Simple methodology, no sample dilutions are necessary
• A 2 step incubation allows the formation of large, easy to read zones of haemolysis
• Results are interpreted easily without the need for expensive equipment 
• Assays are supplied in kit format for ease of use
• 1, 2 or 3 plate kits are available to suit individual laboratory requirements 

If a deficiency in one of the complement pathways is detected after screening, the level of individual complement components may be measured separately.

Binding Site supplies a wide range of assays (automated, semi-automated and RID) for quantitative assessment of complement components.

These assays have been developed to quantify the levels of complement proteins C3c and C4 in human serum. Measurement of C3c and C4 aid in the diagnosis of immunologic disorders, especially those associated with deficiencies of complement components.

 Other assays are available on the Binding Site SPAplus

# Diluted sample applied - assay range may be extended using undiluted sample.
* Research use only
 

More assays are available on the MININEPH and the MININEPHplus™.

1. De Vries E. Patient-centred screening for primary immunodeficiency: a multi-stage diagnostic protocol designed for non-immunologists. Clin Exp Immunol 2006;145:204-214
2. Bonilla FA, et al. Practice parameter for the diagnosis and management of primary immunodeficiency. Ann Allergy Asthma Immunol 2005; 94:S1-63
3. Botto M, et al. Complement in human diseases: Lessons from complement deficiencies. Mol Immunol 2009; 46:2774-2783 
4. Kabat EA, et al. Complement and Complement Fixation. Experimental Immunochemistry 1967