EXPRESSION OF GRANULOCYTE-COLONY-STIMULATING FACTOR-RECEPTOR ON CD10-POSITIVE HUMAN B-CELL PRECURSORS

We examined the expression of CD10 and G-CSF receptor (G-CSFR) on the lymphoid population of mononuclear cells obtained from bone marrow (BM ) using two-colour analysis. In the BM of children with ALL in G-CSF r emission, the CD10(+) population was significantly increased (20.6 +/- 5.1% compared with that of controls (2.5 +/-.0.5%). More than half (6 1.3 +/- 2.9%) of the CD10(+) cells co-expressed G-CSFR, but not CD13. These results indicate G-CSFR(+) B-cell precursors are markedly increa sed in BM of ALL in remission, suggesting the probable involvement of G-CSF in the human early B-cell ontogeny.