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Updated: May 15, 2026
08:26
Measuring the 50% Haemolytic Complement (CH50) Activity of Serum
Published on: March 29, 2010
The complement system in bullous pemphigoid. I. Complement and component levels in sera and blister fluids
The Journal of Clinical Investigation
|May 1, 1973
Summary
Complement levels are reduced in bullous pemphigoid blisters, suggesting local complement activation via classical and alternate pathways in patients with circulating antibodies.
Area of Science:
- Immunology
- Dermatology
- Biochemistry
Background:
- Bullous pemphigoid is an autoimmune blistering disease.
- Complement system plays a role in inflammatory processes.
- Understanding complement's role in blister fluid is crucial.
Purpose of the Study:
- To investigate complement component levels in bullous pemphigoid blister fluid.
- To determine if complement is activated locally within blisters.
- To compare complement levels in bullous pemphigoid with other blistering diseases.
Main Methods:
- Analysis of total hemolytic complement and individual complement components in serum and blister fluid.
- Measurement of transferrin and IgG levels.
- Assay for C3 proactivator conversion.
Main Results:
- Total hemolytic complement and most individual components were reduced in bullous pemphigoid blister fluid compared to serum.
- Transferrin and IgG levels were similar in serum and blister fluid.
- C3 proactivator conversion was observed in blister fluid but not serum of positive cases.
- Blister fluid complement levels in other bullous diseases approached serum levels.
Conclusions:
- Local activation of the complement sequence occurs in bullous pemphigoid blisters.
- Both classical and alternate complement pathways appear to be activated.
- Findings suggest a role for local complement activation in bullous pemphigoid pathogenesis.
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