CD45RO (UCHL1, A6, OPD4)

Antibodies are effective on paraffin-embedded tissue².

Immunohistochemical expression

90% of cortical thymocytes

• 50% of medullary thymocytes

• 50-70% of CD2-/CD3+ peripheral lymphocytes

• rarely with benign B lymphocytes

• mature monocytes and macrophages with UCHL1¹ but not OPD4

• granulocytes¹

• some intestinal intra-epithelial lymphocytes are CD 45RO negative

Diagnostic utility

• differentiation of low grade T cell from low grade B cell lymphoma: sensitivity 95%, specificity 95%

• differentiation of high grade T cell from high grade B cell lymphoma: sensitivity 80%, specificity 85%

See: comparison of sensitivities and specificities of T and B cell markers

References

¹M Steward et al. Production and characterization of a new monoclonal antibody effective in recognizing the CD3 T-cell associated antigen in formalin-fixed embedded tissue. Histopathology 1997;30:16-22.

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

©SMUHT/PW Bishop