Y. Bastion et al., IL-3 INCREASES MARROW AND PERIPHERAL ERYTHROID PRECURSORS IN CHRONIC PURE RED-CELL APLASIA PRESENTING IN CHILDHOOD, British Journal of Haematology, 89(2), 1995, pp. 413-416
In most patients with Diamond-Blackfan anaemia (DBA) the addition of I
L-3 to in vitro cultures increases the number of erythroid progenitors
. However, a small proportion of patients show an erythroid response t
o in vivo administration of IL3. We treated two adult patients with co
rticosteroid-refractory DBA, who had shown a clear in vitro erythroid
response to IL-3, with increasing doses of IL-3 (from 2.5 to 10 mu g/k
g/d) by subcutaneous infections for 7 and 9 weeks. Monitoring of marro
w and circulating progenitors showed a sustained elevation of BFU-E an
d CFU-E as well as an increase of other progenitors and CD34(+) cells
during therapy. However, this effect did not translate into a clear cl
inical response, although transfusion requirements decreased transient
ly in one patient. This report shows that a sustained elevation of ery
throid progenitors induced by in vivo IL-3 administration may not tran
slate into an increase of mature red cells production in DBA patients.