CD2

CD2 corresponds tothe sheep red blood cell E-rosette receptor. It is also known as T11 antigen and LFA-3 antigen (leukocyte function associated antigen-3). CD2 expression commnences after CD7 but before CD1.

Antibodies are said to be effective on fresh-frozen tissue only2, but others have achieved good results on formalin-fixed paraffin-embedded tissue by retrieving in TrisEDTA pH9 at 92.5 degrees C, using the Mach4 detection system.

Immunohistochemical expression

All T lymphocytes and natural killer cells. It is not expressed by B lymphocytes.

It is not expressed by normal myeloid cells or by normal mast cells, but is expressed by mast cells in mastocytosis.

some T-ALL/T-LBL
acute promyelocytic and myelomonocytic leukaemias with inv(16).

Diagnostic utility

A a pan-T cell marker. Aberrant loss of expression may occur in T-cell lymphomas and may help to distinguish them from reactive T-cell proliferations1.

References

1Bakels, V., van Oostveen, J.W., van der Putte, S.C., Meijer, C.J. and Willemze, R. Immunophenotyping and gene rearrangement analysis provide additional criteria to differentiate between cutaneous T-cell lymphomas and pseudo- T-cell lymphomas. Am J Pathol 1997;150:1941-9.

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