Correlation between cell size and CD38 expression in chronic lymphocytic leukaemia.
Both CD38 expression and increased cell size are features of B-lymphocyte activation and have been implicated as adverse prognostic factors in B-cell chronic lymphocytic leukaemia (CLL). We therefore examined the relationship between these two variables by FACS analysis in 140 consecutive CLL patients. Using the mean forward-angle light scatter (FSC) as a measure of cell size, circulating B lymphocytes were found to be significantly larger in "CD38-positive" cases (those in which the antigen was expressed in at least 20% of the malignant cells) as compared with "CD38-negative" patients (p = 0.029). Furthermore, within individual cases B lymphocytes expressing CD38 were, on average, significantly larger than cells that did not express the antigen (p < 0.0001). Finally, when B lymphocytes of individual "CD38-positive" cases were arbitrarily divided into large and small subpopulations using their mean FSC as a cut-off, CD38 was found to be more frequently expressed on the larger cells (p < 0.0001). This strong positive correlation between CD38 expression and cell size implicates cell activation as a possible underlying determinant of both tumour-cell phenotype and clinical outcome in CLL.
Manocha
Sameer
S
Department of Haematology, Level 2 Duncan Building, Royal Liverpool University Hospital, Liverpool L7 8XP, UK.
Matrai
Zoltan
Z
Osthoff
Michael
M
Carter
Anthony
A
Pettitt
Andrew R
AR
D036541:ADP-ribosyl Cyclase / Q000032:analysis*; D051997:ADP-ribosyl Cyclase 1; D015703:Antigens, CD / Q000032:analysis*; D001402:B-Lymphocytes / Q000473:pathology; D048429:Cell Size; D003627:Data Interpretation, Statistical; D005434:Flow Cytometry; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000473:pathology*; D008213:Lymphocyte Activation; D016393:Lymphoma, B-Cell / Q000473:pathology; D008562:Membrane Glycoproteins; D011379:Prognosis
D015703:Antigens, CD; D008562:Membrane Glycoproteins; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D051997:ADP-ribosyl Cyclase 1