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Complement C4a MeSH Descriptor Data 2025


MeSH Heading
Complement C4a
Tree Number(s)
D12.776.124.486.274.024.260
D12.776.124.486.274.350.250
Unique ID
D015934
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D015934
Scope Note
The smaller fragment formed when complement C4 is cleaved by COMPLEMENT C1S. It is an anaphylatoxin that causes symptoms of immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE) but its activity is weaker than that of COMPLEMENT C3A or COMPLEMENT C5A.
Entry Term(s)
C4a Complement
Complement 4a
Complement Component 4a
Pharm Action
Immunologic Factors
Registry Numbers
80295-49-4
CAS Type 1 Name
Complement C4a
Previous Indexing
Anaphylatoxins (1980-1982)
Complement 4 (1978-1989)
Public MeSH Note
2006; see COMPLEMENT 4A 1990-2005
History Note
2006 (1990)
Date Established
1990/01/01
Date of Entry
1989/05/25
Revision Date
2005/06/30
Complement C4a Preferred
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