Haematologica. 2003 Aug;88(8):864-73.

Expression of CD10 by B-chronic lymphocytic leukemia cells undergoing apoptosis in vivo and in vitro.

Morabito F, Mangiola M, Rapezzi D, Zupo S, Oliva BM, Ferraris AM, Spriano M, Rossi E, Stelitano C, Callea V, Cutrona G, Ferrarini M.
Dipartimento di Ematologia Azienda, Ospedaliera Bianchi-Melacrino, Reggio Calabria, Italy.

BACKGROUND AND OBJECTIVES: B-cell chronic lymphocytic leukemia (B-CLL) is an accumulating disease of slowly proliferating cells. CD10 is not normally expressed on the surface of B-CLL cells. The aim of this study was to ascertain whether B-CLL cells, induced into apoptosis, expressed surface CD10, since a correlation between apoptosis and CD10 expression has been demonstrated. DESIGN AND METHODS: Peripheral blood cells from 31 untreated B-CLL patients were induced into apoptosis by etoposide, fludarabine or Ga(mu)-Ab treatment and tested for CD10 expression by flow cytometry. Normal CD5+ B cells were also induced into apoptosis and tested for CD10 expression. RESULTS: CD10 positive cells were absent in B-CLL cell suspensions, but were detected following in vitro culture, and their appearance paralleled that of apoptotic cells. Treatment with etoposide, fludarabine or Ga(mu)-Ab enhanced both apoptosis and CD10 expression. Inhibition of apoptosis by VAD-fmk or Ga(delta)-Ab prevented CD10 expression. Cell separation tests following induction of apoptosis demonstrated that CD10+ cells were apoptotic. CD10+ cells were observed in the peripheral blood of two patients within a few hours following fludarabine infusion. In another patient, who failed to respond, no CD10+ cells were seen. Expression of CD10 was observed also in normal CD5+ B cells when these were induced into apoptosis. INTERPRETATION AND CONCLUSIONS: This study demonstrates that B-CLL cells, as well as normal CD5+ B cells, become CD10+ following apoptosis induction in vitro. Some of the data obtained also suggest a use for CD10 to monitor apoptosis of B-CLL in a clinical setting.

PMID: 12935974 [PubMed - indexed for MEDLINE]