THE VALUE OF IMMUNOHISTOCHEMISTRY
IN THE ASSESSMENT OF BONE MARROW DISORDERS

Attilio Orazi, M.D., FRCPath. and Dennis P. O'Malley, M.D.

CD3 Anti-CD3 is a polyvalent rabbit antibody made to human T cells. We believe it is the single antibody of choice in screening for T cell lymphomas and T cell proliferations, being more specific than CD45Ro (UCHL1), which we no longer use. We use a heat induced epitope retrieval method and find that the antibody works well in both formalin and B5-fixed material and in decalcified material. We have found that the majority of T cell lymphomas stain with CD3 although occasional tumors occur in which the antigen is deleted as part of the neoplastic process. This is most likely to occur in high grade T cell lymphomas or in anaplastic large cell lymphomas. References Anderson C, Rezuke WN, Kosciol CM, Pastuszak WT, Cartun RW. Identification of T-cell lymphomas in paraffin-embedded tissues using polyclonal anti-CD3 antibody: comparison with frozen section immunophenotyping and genotypic analysis. Modern Pathology 1991;4:358. Campana D, Thompson JS, Amlot P, Brown S, Janossy G. The cytoplasmic expression of CD3 antigens in normal and malignant cells of the T lymphoid lineage. J Immunol 1987;138:648. Erber WN, Pinching AJ, Mason DY. Immunocytochemical detection of T cell and B cell populations in routine blood smears. Lancet 1984;1:1042. Mason DY, Cordell J, Brown M, et al. Detection of cells in paraffin wax embedded tissue using antibodies against a peptide sequence from the CD3 antigen. J Clin Pathol 1989;42:1194. Mason DY, Krissansen GW, Davey FR, Crumpton MJ, Gatter KC. Antisera against epitopes resistant to denaturation on T3 (CD3) antigen can detect reactive and neoplastic T cells in paraffin embedded tissue biopsy specimens. J Clin Pathol 1988;41:121. Picker LJ, Weiss LM, Meideros LJ. Wood DW, Warnke RA. Immunophenotypic criteria for the diagnosis of non-Hodgkin's lymphomas. Am J Clin Pathol 1987;128:1811.