CD68 (KP1, PG-M1)

This is the macrophage marker in most widespread routine use. The antigen is expressed by a cytoplasmic protein associated with lysosomes.

Antibodies are effective on paraffin-embedded tissue2.

Immunohistochemical expression

Diagnostic utility

CD68 is less specific than is CD163 as a marker of monocyte/macrophages.


1Pernick, N. L., DaSilva, M., Gangi, M. D., Crissman, J., Adsay, V. "Histiocytic markers" in melanoma. Mod Pathol 1999;12:1072-7.

2Leong A S-Y, Cooper K and Leong FJ W-M. Manual of diagnostic antibodies for immunohistology. 2nd edition, 2003


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