CD 68 is useful in immunohistochemistry as it is found on cells that are part of the monocyte lineage like macrophages. This is useful as a positive result can help determine the origin of a tumour type.

Unfortunately in IHC there can be a staining artefact from lyosome rich granules, this can sometimes lead to false positive staining, so need to be careful when using this for diagnosis. The staining pattern of CD68 is cytoplasmic as shown below.

Picture 1 – CD68 positivity in Spleen

 

CD68 has several different applications. Below are a few examples.

Tumour or cell type	CD 68 + or -
Histocytic lesions	Positive
Myelomonocytic Acute Myeloid leukaemia	Positive
Monocyte lineage cells	Positive
Lymphocytes	Negative