Macrophage-1 antigen
complement receptor

Macrophage-1 antigen (or integrin αMβ2 or macrophage integrin or Mac-1) is an integrin complement receptor ("CR3") consisting of CD11b (integrin αM) and CD18 (integrin β2).
The integrin α chain is noncovalently bound to the integrin β chain. It binds to iC3b and can be involved in cellular adhesion, binding to the intercellular adhesion molecule-1 (ICAM-1). CR3 causes phagocytosis and destruction of cells opsonized with iC3b. CR3 and CR4 are thought to exhibit overlapping functions; however, the distinct binding sites to iC3b suggests differences in their functions. Additionally, CR3 has been shown to have therapeutic promise.
Function
Macrophage-1 antigen (hereafter complement receptor 3 or CR3) (CD11b/CD18) is a human cell surface receptor found on B and T lymphocytes, polymorphonuclear leukocytes (mostly neutrophils), NK cells, and mononuclear phagocytes like macrophages. CR3 is a pattern recognition receptor, capable of recognizing and binding to many molecules found on the surfaces of invading bacteria. CR3 also recognizes iC3b when bound to the surface of foreign cells. iC3b is generated by proteolysis of C3b and binding to the receptor causes phagocytosis and destruction of the foreign cell opsonized with iC3b.
This brief starts where responsible research should: with the source description of “Macrophage-1 antigen” as complement receptor. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as complement receptor. Its deeper value depends on whether names, dates, institutions and citations support that framing.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 13, 2026. The linked authority identifier is Q4043525. None of the 0 selected statements returned an explicit reference.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Macrophage-1 antigen”, its source revision and the description used here.
- Expand the search: follow Macrophage-1 antigen primary sources, Macrophage-1 antigen archive and Macrophage-1 research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Macrophage-1 antigen”?
- Which cited source is closest to the event, object or claim?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “Macrophage-1 antigen” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.