Monocytes are differentiated from the myeloblasts in the bone marrow. Post differentiation, a proportion of monocytes remains in the blood and the rest randomly migrate into the tissue and body cavities. This process is known also as leucocyte extravasation. Post extravasation monocytes differentiate into macrophages. Also, circulating monocytes migrate to tissues in response to injury. This process is known as monocyte extravasation and is guided by the chemoattractants produced at the site of injury. The interactions between monocyte surface integrins and intercellular adhesion molecules on the endothelial cell surface initiates monocyte extravasation. Monocytes extert cytotoxic actions against the foregin pathogen.

Following migration to tissues or body cavities, monocytes are differentiated to macrophages. The general functions of macrophages are phagocytosis of cellular debris and pathogens, cytokine production, managing of inflammatory responses and antigen presentation to initiate adaptive immune responses. Macrophages express pattern recognition receptor (PRR) and co-receptors to identify foregin pathogens. Macrophages are plastic cells; the phenotypical switch of macrophages is known as macrophage polarization. During macrophage polarization, a specific macrophage phenotype is mounted in response to a specific stimulus and/or group of stimuli.

CD11a

Alternative names Integrin alpha-L, LFA-1A, ITGAL

Intracellular adhesion and costimulation. Binds with CD18 to form LFA1, which then interacts with ICAM-1.

We recommend

Browse all CD11a antibodies

CD11b

Alternative names Integrin alpha-M, CR3A, ITGAM, MAC-1

Regulates macrophage polarization, inhibits immune suppression, modulates neovascularization and cancer.

We recommend

Anti-CD11b antibody [M1/70] (ab8878)

Anti-CD11b antibody [ICRF44] (ab34216)

CD11c

Alternative names Integrin alpha-X, ITGAX, SLEB6

Cell adhesion. Gatekeeper for lymphocyte trafficking.

We recommend

Browse all CD11c antibodies

CD14

Alternative names Monocyte differentiation antigen CD14

Receptor for LPS and LBP complex.

We recommend

Anti-CD14 antibody [SP192] (ab183322)

Anti-CD14 antibody [MEM-18] - Low endotoxin, Azide free (ab6083)

Browse CD14 antibodies for flow cytometry

CD18

Alternative names Integrin beta-2, ITGB2, MFI7, LAD, LCAMB, LFA-1

Forms the beta 2 chain of CD11a-c enabling cell adhesion.

We recommend

Browse all CD18 antibodies

CD16a

Alternative names Fc-gamma RIII-alpha, FCGR3A, FCG3, FCGR3, IGFR3

Mediates phagocytosis and ADCC. Low affinity Fc receptor.

We recommend

Anti-CD16 antibody [EPR22409-124] (ab246222)

Browse CD16 antibodies for flow cytometry

CD64

Alternative names IgG Fc receptor I, FCGR1A, IGFR1

Binds to the Fc region of IgG with high affinity, expression induced by bacterial infection.

We recommend

Anti-CD64 antibody [EPR4623] (ab109449)

Browse CD64 antibodies for flow cytometry

CD68

Alternative names SCARD1, KP1

Specific marker for tumor-associated macrophages (TAMs). Positive cells infiltrate tumors which reflects severity. Binds to tissue- and organ-specific lectins or selectins, allowing homing of macrophage subsets to particular sites. Possible role in phagocytic activities of tissue macrophages. May allow macrophages to crawl over selectin-bearing substrates or other cells.

We recommend

Anti-CD68 antibody [SP251] (ab192847)

Anti-CD68 antibody [KP1], prediluted (ab845)

CD80

Alternative names B7-1

Co-stimulation of T-cell activation and proliferation. Plays a role in B-cell activity. Has a critical role in autoimmune, humoral, and transplant responses.

We recommend

Anti-CD80 antibody [EPR1157(2)] (ab134120)

Anti-CD80 antibody [EPR22183] (ab225674)

CD163

Alternative names M130

Clearance and endocytosis of hemoglobin/haptoglobin complexes by macrophages, expressed on TAMs and strong indicator of poor prognosis.

We recommend

Anti-CD163 antibody [EPR19518] (ab182422)

CD206

Alternative names MMR, MRC1, CLEC13D

Receptor that mediates endocytosis of glycoproteins by macrophages.

We recommend

Anti-Mannose Receptor antibody [15-2] - Low endotoxin, Azide free (ab270634)

Browse CD206 antibodies for flow cytometry

Further reading

See the references below for a list of relevant reviews.

References

View 6 references for Further reading

References

Further reading

Novershtern, N., et al. Densely interconnected transcriptional circuits control cell states in human hematopoiesis  Cell   144 ,296-309 (2011)

Wood, B. Multicolor Immunophenotyping: Human Immune System Hematopoiesis  Methods Cell Biol.  75 ,559-576 (2004)

Yang, J., Zhang, L., Yu, C., et al. Monocyte and macrophage differentiation: circulation inflammatory monocyte as biomarker for inflammatory diseases  Biomark. Res.   2 (1), (2014)

Kapellos, T. S., Bonaguro, L., Gemünd, I., et al. Human Monocyte Subsets and Phenotypes in Major Chronic Inflammatory Diseases  Front Immunol   30 (10), (2019)

Murray, P. J., Wynn, T. A. Protective and pathogenic functions of macrophage subsets  Nat. Rev. Immunol.  11 ,723-737 (2011)

Pilling, D., Fan, T., Huang, D., et al. Identification of markers that distinguish monocyte-derived fibrocytes from monocytes, macrophages, and fibroblasts  PLoS One   4 ,31-33 (2009)