CD27 in B-cell chronic lymphocytic leukemia. Cellular expression, serum release and correlation with other soluble molecules belonging to nerve growth factor receptors (NGFr) superfamily.
OBJECTIVE
CD27, a transmembrane homodimer belonging to the nerve growth factor (NGF) receptor superfamily, is typically expressed on leukemic CD5+ cells in B-cell chronic lymphocytic leukemia (CLL) and found in soluble form in the serum of CLL patients. Therefore, we investigated clinico-biological implications of increased serum levels of sCD27 in an unselected series of B-CLL patients.


METHODS
Serum CD27 (sCD27) levels were determined at the time of diagnosis in 82 previously untreated B-CLL patients using a sandwich enzyme-linked immunoassay (ELISA). Results were correlated with either clinico-hematological or biological features. Finally, quantitative flow cytometric analyses of membrane CD27 (mCD27) expression were carried out on peripheral blood (PB) cells of 22 B-CLL patients and 5 healthy controls, respectively.


RESULTS
CD27 was found to be expressed on the surface of both resting normal and leukemic B cells. sCD27 levels were significantly higher in B-CLL patients (median value 2150 U/mL) than in healthy controls (median value 220 U/mL) (p < 0.0001). There was a close relationship between sCD27 and soluble TNF-alpha, another molecule belonging to the NGF receptor superfamily. Changes in sCD27 level correlated with clinical stage, beta 2 microglobulin and LDH.


CONCLUSIONS
These findings indicate that sCD27 is a reliable marker of tumor mass in B-CLL. Its potential prognostic value should be tested in prospective studies.
Molica
S
S
Divisione Ematologia, Azienda Ospedaliera Pugliese-Ciaccio, Catanzaro, Italy.
Vitelli
G
G
Levato
D
D
Crispino
G
G
Dell'Olio
M
M
Dattilo
A
A
Matera
R
R
Gandolfo
G M
GM
Musto
P
P
D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D005810:Multigene Family; D017475:Receptors, Nerve Growth Factor / Q000235:genetics*; D012995:Solubility; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000097:blood*
D017475:Receptors, Nerve Growth Factor; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7