Erythropoiesis in Familial Erythrocytosis

Abstract

We found primary erythrocytosis in two male siblings with hematologically normal parents. To clarify the abnormalities in erythropoiesis, we studied erythropoietin production in the older sibling as well as in vivo and in vitro responses of bone marrow to various stimuli. His erythropoietin excretion after a 1000-ml phlebotomy increased by 0 to 11 units per day. In liquid-suspension culture, erythropoiesis was prominently augmented by erythropoietin and unstimulated erythropoiesis was greater and more prolonged than normal. Numbers of erythroid colonies rose in methylcellulose culture without exogenous erythropoietin, and cloning increased with added erythropoietin. Anti-erythropoietin antibody substantially decreased erythropoiesis in vitro. Increased bone-marrow erythropoiesis was also demonstrated in murine diffusion chambers. The principal abnormality in this familial erythrocytosis appears to be a greatly expanded erythropoietic precursor pool that is responsive to erythropoietin in vitro and in vivo. This abnormality is analogous to the functional erythropoietic defect in typical polycythemia vera.

Endogenous Erythroid Colony Formation by Peripheral Blood Mononuclear Cells from Patients with Myelofibrosis and Polycythemia Vera

“…This difference in the erythroid colony-forming ability of peripheral blood mononuclear cells between polycythemia vera and sec ondary polycythemia may offer the poten tial of a useful diagnostic tool in helping dis tinguish between these clinical states when other diagnostic criteria are equivocal. Nev ertheless, the specificity of such colony growth has to be questioned since there are rare examples of familial erythrocytosis in which spontaneous erythroid colony forma tion has occurred and which probably do not represent polycythemia vera [8]. The present studies also demonstrate the pres ence of a population of cells in peripheral blood of patients with both polycythemia vera and myelofibrosis associated with mye loid metaplasia that respond to exogenous Epo in culture.…”

Inheritance of the chronic myeloproliferative neoplasms. A systematic review

“…They do not meet the criteria of either WHO2008 or PVSG for classical MPNs and have not excluded potential differential diagnoses (28)(29)(30)(31)(32)(33)(34). Further, many of the revised studies from before 1950 are excluded.…”

Expression of Bcl-x in Erythroid Precursors from Patients with Polycythemia Vera

“…15 In contrast, erythroid progenitors from bone marrow or peripheral blood of patients with polycythemia vera give rise to colonies in the absence of erythropoietin. 16,17 The erythropoietinindependent formation of erythroid colonies is a hallmark of polycythemia vera and can be used to distinguish polycythemia vera from secondary polycythemia. 18 Erythropoietin is needed for normal erythroid maturation, 15,19 but the mechanism by which it controls this process is unknown.…”