Asynchronous antigen expression in B lineage acute lymphoblastic leukemia.
Cell surface phenotypes of 113 B lineage acute lymphocytic leukemia (ALL) cases, defined by the presence of HLA-DR and at least one B-cell-specific antigen (either CD19, CD20, or CD22), were compared with antigen-defined stages of normal B lymphocyte development. The cases were first evaluated for expression of HLA-DR, CD19, CD34, CD10, CD20, and CD22 by indirect one-color immunofluorescence. Pairwise comparisons of cell surface marker expression were performed for each leukemic sample: no correlations were observed for paired antigen expression on the leukemic samples using antigens expressed either early or late during normal B lymphoid development. Complete immunophenotypes of the cases were then compared with normal B-cell developmental stages. Sixteen different complete immunophenotypes were observed on the leukemias that were not found in normal marrow; at least 78% of the cases demonstrated such "asynchronous" combinations of B lymphoid-associated differentiation antigens. Several samples were subsequently studied by two-color immunofluorescence, and the presence of doubly labeled cells with "asynchronous" antigen combinations was confirmed. These results indicate that the majority of B lineage leukemias exhibit "developmental asynchrony," as compared with normal marrow B cells. The data further suggest that ALL cases do not accurately represent cells arrested at the stage where the leukemogenic event occurred. Rather, ALL appears to be a disease in which there may be maturation of leukemic blasts; but this maturation is "asynchronous" when compared with the normal developmental process.
Hurwitz
C A
CA
Johns Hopkins Oncology Center, Pediatric Oncology, Baltimore, MD 21205.
Loken
M R
MR
Graham
M L
ML
Karp
J E
JE
Borowitz
M J
MJ
Pullen
D J
DJ
Civin
C I
CI
D000328:Adult; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology* / Q000473:pathology; D002454:Cell Differentiation; D002648:Child; D005455:Fluorescent Antibody Technique; D006801:Humans; D007945:Leukemia, Lymphoid / Q000145:classification / Q000276:immunology* / Q000473:pathology; D010641:Phenotype
D000944:Antigens, Differentiation, B-Lymphocyte; D000951:Antigens, Neoplasm