INVESTIGADORES
RAMHORST Rosanna Elizabeth
artículos
Título:
Modulation of CD44 on acute lymphoblastic leukemia identifies functional and phenotipic differences of human B cell precursors
Autor/es:
S. ZITTERMAN, B. ACHINO, E. AGRIELLO, N. HALPERÍN, R. RAMHORST AND L. FAINBOIM
Revista:
EUROPEAN JOURNAL OF HAEMATOLOGY
Editorial:
Munksgaard
Referencias:
Lugar: Copenhagen; Año: 2001 vol. 66 p. 377 - 382
ISSN:
0902-4441
Resumen:
Abstract: CD44 expression and other B cell markers were analyzed in 38
samples of B cell precursors (BCP) from patients with acute
lymphoblastic leukemia (ALL). According to the expression of CD10
and CD44, we established the following ®ve stages of BCP-ALL
phenotypes that may represent different forms of interaction between
BCP-ALL and bone marrow-adherent cells: stage 1, CD19+, CD44bright,
CD10x; stage 2, CD19+, CD44bright, CD10dim/bright; stage 3, CD19+,
CD44dim, CD10bright, CD20x/+; stage 4, CD19+, CD44dim, CD10dim,
CD20+; and stage 5, CD19+, CD44bright, CD10x, CD20+. Next, we
analyzed the modulation of CD44 according to the expression of the
different BCP-ALL phenotypes by incubating the samples under
different culture conditions, including addition of stromal cells and
interleukin (IL)-7. In culture, the samples in stages 1 and 2 maintained
high expression of CD44 and re-expressed this molecule when cultured
after trypsin treatment, indicating ongoing synthesis of CD44. Similarly,
the stage 3 samples cultured in the presence of stromal cells, IL-7, or both
also upregulated CD44 expression in culture. In contrast, the low
expression of CD44 on the presumably more mature stage 4 samples was
not modi®ed by the addition of stromal cells or IL-7 or when cultured
after trypsin treatment, suggesting that those cells had arrested CD44
synthesis. We concluded that down-modulation of CD44 occurred in
association with differentiation to phenotype stages 3 and 4 and we
hypothesized that this down-modulation might be associated with the