The diagnostic value of CD123 in B-cell disorders with hairy or villous lymphocytes.
OBJECTIVE
CD123 is an antibody that identifies the a chain of the human interleukin-3 receptor and is expressed in a variety of normal hematopoietic cells, acute leukemia and hairy cell leukemia (HCL). The aim of the study was to investigate the diagnostic value of CD123 expression in B-cell disorders with circulating hairy and villous lymphocytes.


METHODS
We investigated the diagnostic value of CD123 expression in neoplastic cells from 59 patients with B-cell disorders with circulating hairy or villous lymphocytes: HCL (n=24), the variant form of HCL (n=11) and splenic lymphoma with villous lymphocytes (SLVL) (n=24). Cells from 12 patients with chronic lymphocytic leukemia were used as controls. Immunophenotypic analysis was performed by flow cytometry on 77 samples from peripheral blood (n=48), bone marrow (n=25) and spleen cell suspensions (n=4).


RESULTS
Our findings show that cells from 95% of typical HCL express CD123 with strong to moderate intensity while this molecule is absent in circulating cells from most cases of HCL-variant (91%) and SLVL (97%).


CONCLUSIONS
We conclude that CD123 is a useful new marker for distinguishing B-cell disorders with circulating villous lymphocytes as its expression is characteristic of typical HCL with high sensitivity and specificity. However CD123 does not allow the distinction between HCL-variant and SLVL, as both are CD123 negative.
Del Giudice
Ilaria
I
Academic Department of Hematology and Cytogenetics, The Royal Marsden Hospital and Institute of Cancer Research, London, UK.
Matutes
Estella
E
Morilla
Ricardo
R
Morilla
Alison
A
Owusu-Ankomah
Kwasi
K
Rafiq
Furheen
F
A'Hern
Roger
R
Delgado
Julio
J
Bazerbashi
Mohammed Badie
MB
Catovsky
Daniel
D
D000911:Antibodies, Monoclonal / Q000276:immunology; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D053650:Interleukin-3 Receptor alpha Subunit; D007943:Leukemia, Hairy Cell / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism; D008214:Lymphocytes / Q000378:metabolism* / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000175:diagnosis* / Q000378:metabolism; D016185:Receptors, Interleukin-3 / Q000096:biosynthesis* / Q000276:immunology; D012680:Sensitivity and Specificity; D013160:Splenic Neoplasms / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; C115022:IL3RA protein, human; D053650:Interleukin-3 Receptor alpha Subunit; D016185:Receptors, Interleukin-3