Variations in growth responsiveness of burst forming units-erythroid colonies [letter; comment]

Bhaumik, Kabita

doi:10.1182/blood.v75.2.524.524

Cited by 2 publications

(1 citation statement)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recent reports (Bhaumik, 1990;Croizat & Nagel, 1990) suggest that circulating BFU-E growth factor responsiveness varies among SS patients: thus, the sensitivity to the cytokine may be a useful way of further defining the phenotypic characteristics of the BFU-E subsets in LFSS and HFSS patients.…”

Section: Bfu-ementioning

confidence: 99%

Inhomogeneity of the circulating BFU‐E regulation in sickle cell anaemia: accessory cells properties and BFU‐E growth factor response pattern

Croizat

Nagel

1993

Br J Haematol

View full text Add to dashboard Cite

Sickle cell anaemia (SS) patients with low (< 9%) HbF levels (LFSS) are characterized by an increased number of circulating BFU-E in active DNA synthesis, and release of burst promoting activity (BPA) by unstimulated low density (LD) adherent cells. In contrast, circulating BFU-E from SS patients with high (> 9%) HbF levels (HFSS) are normal in number, largely in resting phase, and their LD cells do not release BPA-like activity. We report now that in LFSS patients, adherent cell depletion decreases BFU-E growth in culture and apparent BFU-E cycling. Furthermore, addition of conditioned media (CM) from LD cells of LFSS patients restored cycling BFU-E expression in culture. Neutralization analysis with anti-GM-CSF antibody demonstrated that GM-CSF is, at least, one factor responsible for BPA activity present in this CM. Thus, GM-CSF is constitutively produced by unstimulated monocytes in LFSS patients. In contrast, HFSS patients' adherent cell depletion increases cycling of BFU-E in culture. CM from HFSS patients inhibits BFU-E expression in culture. Hence, LD adherent cells from HFSS patients may release a yet unknown inhibitor factor(s). In addition, we report a distinct response pattern in SS patients' BFU-E to growth factor (GM-CSF, IL-3): (a) LFSS patients have a BFU-E population, equally responsive to GM-CSF and IL-3; (b) HFSS patients, have a subset of BFU-E exclusively dependent on IL-3 (20-40% of the circulating BFU-E). This pattern is very similar to that of normal BFU-E. In conclusion, BFU-E from LFSS patients represent an actively proliferating population, equally responsive to GM-CSF and IL-3, controlled by constitutively produced GM-CSF, suggesting a unique BFU-E behaviour in SS patients with low HbF levels and high haemopoietic stress. The heterogeneous regulation of BFU-E in SS disease seems to be the epiphenomenon of HbF levels, and not vice versa.

show abstract

Section: Bfu-ementioning

confidence: 99%

Inhomogeneity of the circulating BFU‐E regulation in sickle cell anaemia: accessory cells properties and BFU‐E growth factor response pattern

Croizat

Nagel

1993

Br J Haematol

View full text Add to dashboard Cite

show abstract

Early circulating erythroid progenitors (BFU-E) in sickle cell anemia

Croizat

1993

Experientia

View full text Add to dashboard Cite

Sickle cell anemia (SS) patients can be divided into two sub-populations according to peripheral HbF levels. Patients with low (< 9%) HbF levels (LFSS) are characterized by an increased number of circulating BFU-E in active DNA synthesis, and release of burst promoting activity (BPA) by unstimulated low density (LD) adherent cells. In contrast, circulating BFU-E from SS patients with high (> 9%) HbF levels (HFSS) are normal in number, largely in resting phase, and their LD cells do not release BPA-like activity. More recently further heterogeneity has been found among these two groups. In LFSS patients GM-CSF is constitutively produced by unstimulated monocytes. In contrast, HFSS patients' adherent cell depletion increases cycling of BFU-E in culture. CM from HFSS patients inhibits BFU-E expression in culture. Hence, LD adherent cells from HFSS patients may release an inhibitory factor(s). The nature of this factor has to be determined. In addition, there are distinct subpopulations of BFU-E responsiveness to growth factor (GM-CSF, IL-3): a) LFSS patients have a homogeneous BFU-E population, equally responsive to GM-CSF and IL-3; b) HFSS patients, in addition to this subpopulation, have a subset of BFU-E dependent exclusively on IL-3 which is 20 to 40% of the total number of circulating BFU-E. This is similar to BFU-E from normal individuals. Hence, LFSS BFU-E represent an actively proliferating population, equally responsive to GM-CSF and IL-3, controlled by at least constitutively produced GM-CSF and possibly other factors. These observations suggest a significant modification in BFU-E behavior in the subset of SS patients with low HbF levels and high hemopoietic stress. The heterogenous regulation of BFU-E in SS disease seems to be an epiphenomenon of HbF levels, and not vice-versa.

show abstract

Variations in growth responsiveness of burst forming units-erythroid colonies [letter; comment]

Cited by 2 publications

References 1 publication

Inhomogeneity of the circulating BFU‐E regulation in sickle cell anaemia: accessory cells properties and BFU‐E growth factor response pattern

Inhomogeneity of the circulating BFU‐E regulation in sickle cell anaemia: accessory cells properties and BFU‐E growth factor response pattern

Early circulating erythroid progenitors (BFU-E) in sickle cell anemia

Contact Info

Product

Resources

About