CD79 alpha expression in acute myeloid leukemia. High frequency of expression in acute promyelocytic leukemia.
CD79 alpha is a subunit of an intracytoplasmic protein reported to be specific for B lymphocytes, including immature B lineage cells. To evaluate expression of the CD79 alpha antigen in acute myeloid leukemia (AML), we studied forty-eight cases of AML by paraffin section immunohistochemistry. The cases included four MO, nine M1, nine M2, ten M3, ten M4, and six M5 AMLs using criteria of the French-American-British cooperative group. Eleven cases demonstrated cytoplasmic staining for the CD79 alpha antigen, including one M1, nine M3, and one M5 AML. These CD79 alpha-positive cases represented 5% of all non-promyelocytic AMLs and 90% of all acute promyelocytic leukemias studied. All acute promyelocytic leukemias had the characteristic t(15;17)(q24;q21), including two cases of the microgranular variant (M3v). No other B-lineage-associated antigens were found in the CD79 alpha-positive cases, with the exception of a subpopulation of CD19-positive leukemic cells in one patient. The two non-promyelocytic leukemias that expressed CD79 alpha had no evidence of t(15;17) and did not express any additional B-lineage-associated antigens that might suggest a mixed lineage proliferation. This study demonstrates that CD79 alpha expression in acute leukemia is not restricted to B-lineage acute lymphoblastic leukemias and that CD79 alpha expression is frequently associated with t(15;17) acute myeloid leukemia.
Arber
D A
DA
Division of Pathology, City of Hope National Medical Center, Duarte, California 91010, USA.
Jenkins
K A
KA
Slovak
M L
ML
D000208:Acute Disease; D000328:Adult; D015703:Antigens, CD / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D051925:CD79 Antigens; D005260:Female; D006801:Humans; D007951:Leukemia, Myeloid / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016612:Paraffin Embedding; D011947:Receptors, Antigen, B-Cell / Q000032:analysis*
D015703:Antigens, CD; D000951:Antigens, Neoplasm; D051925:CD79 Antigens; C497881:CD79A protein, human; D011947:Receptors, Antigen, B-Cell