Erythroid progenitor growth in erythrocytosic transplanted patients.
In 55 patients who underwent renal transplantation, erythrocytosis (E) was observed in 6. In all patients, the growth of erythroid progenitors [burst-forming unit erythroid (BFU-e)], using mononuclear blood cells, was evaluated in in vitro cultures. The results showed a significant increase of serum erythropoietin (s-Ep) in erythrocytosis and in nonerythrocytosis patients with a subsequent decrease when hematocrit (Hct) and hemoglobin (Hb) reached high levels, showing a recovery of a feedback control system. Notwithstanding the diminution of s-Ep, six patients demonstrated further progressive rise of the Hct and Hb to a final state of E. The in vitro BFU-e cultures from these patients showed a noticeable sensitivity to progressively reduced doses of Ep and also the capacity to develop a few colonies when the medium was Ep-free. These results were not verified using peripheral blood depleted of monocyte and/or T lymphocyte cells. Therefore, in transplanted patients with erythrocytosis, it is possible that particular cellular interactions stimulate an early hyperproliferation of BFU-e with a greater Ep sensitivity and at least partly the capacity to grow also in the absence of Ep.
D000328:Adult; D005260:Female; D006412:Hematopoietic Stem Cells / Q000473:pathology*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000601:surgery*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011086:Polycythemia / Q000209:etiology* / Q000473:pathology; D011183:Postoperative Complications