Table of Contents
Definition / general | Pathophysiology | Clinical features | Uses by pathologists | Microscopic (histologic) images | Positive staining - normal | Positive staining - disease | Negative stainingCite this page: Pernick, N. CD11b. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cdmarkerscd11b.html. Accessed March 2nd, 2021.
Definition / general
- Alpha component of an integrin at 16p11-13.1 that mediates adhesion (OMIM #120980)
- Also called integrin alpha M, Mac-1 and CR3A
Pathophysiology
- Mediates monocyte / macrophage / granulocyte adhesion to substrates by opsonization with iC3b, leading to phagocytosis, neutrophil aggregation and chemotaxis
- Ligands include fibrinogen, Factor X, ICAM1, iC3b, Saccharomyces cerevisiae, Staphylococcus epidermidis and Histoplasma capsulatum
- Expression is associated with activation of T cells
Clinical features
- Gr1+ CD11b+ myeloid cells promote metastasis (Cancer Cell 2008;13:23)
- Poor prognostic factor in preB acute lymphoblastic leukemia (Blood 2010;115:3763), cytogenetically unfavorable AML (Leuk Res 2013;37:122)
- Documents maturation of tumor cells in acute promyelocytic leukemia patients receiving all-trans retinoic acid therapy (cells become CD11b+, CD16+, Arch Pathol Lab Med 2003;127:e4) or arsenic trioxide (CD11b+, CD33+, Mod Pathol 2000;13:954)
- Histoplasma capsulatum causes decreased cell surface CD11b expression and an antiapoptotic state on leukocytes (Scand J Immunol 2002;56:392)
- May be useful to diagnose aspirin induced asthma, due to upregulation of CD11b on eosinophils (Allergol Int 2013;62:367)
- rs1143679 variant is associated with SLE, and impairs various CR3 monocyte functions (Ann Rheum Dis 2012;71:2028) and neutrophil functions (Arthritis Rheum 2013;65:2907)
- In Type 2 diabetes, hyperglycemia leads to increased CD11b on granulocytes and monocytes, exacerbating their inflammatory status (J Investig Med 2013;61:972)
Uses by pathologists
- Common myeloid marker and NK (natural killer cell) antigen
- Differentiates recovery from acute agranulocytosis (CD11b+, CD117-) from acute promyelocytic leukemia (CD11b-, CD117+, Am J Clin Pathol 2002;118:31)
- Differentiates Down syndrome patients with AML (usually CD13+, CD11b+) from transient myeloproliferative disorder (usually CD13-, CD11b-, Am J Clin Pathol 2001;116:204)
- May be useful for flow cytometry diagnosis of myelodysplastic syndrome as part of panel (Ann Clin Lab Sci 2012;42:271)
Positive staining - normal
- Granulocytes, macrophages
- Follicular dendritic cells, myeloid cells beginning with promyelocytes, NK cells, some B/T cells
Positive staining - disease
- Hairy cell leukemia (virtually all)
- Also acute myelogenous leukemia (Am J Clin Pathol 2008;129:934), lymphoma (various), sinus histiocytosis with massive lymphadenopathy (Hum Pathol 1992;23:647)
Negative staining
- Gaucher cells (Am J Clin Pathol 2004;122:359)