Autoimmune neutropenia after kidney transplantation: a disregarded entity of posttransplant neutropenia.

Background: Neutropenia is common after kidney transplantation and is associated with an increased incidence of infections. Drug toxicities are the main causes of posttransplant neutropenia (PTN), mainly related to immunosuppressive drugs as mycophenolic acid (MPA) and anti-infectious agents, but some PTN remain unexplained.

Methods: Between January 2012 and January 2013, cultures of autologous granulocytic progenitors from bone marrow aspirate were performed in two patients with unexplained severe neutropenia.

High Id1 expression is associated with poor prognosis in 237 patients with acute myeloid leukemia.

Inhibitors of differentiation (Id) are a group of dominant inhibitors of basic helix-loop-helix transcriptional factors, which promote excessive proliferation, and also protect cells against drug-induced apoptosis in mammalians. Recently, Id1 has been identified as a common downstream target of several constitutively activated oncogenic tyrosine kinase, such as FLT3 internal tandem duplication, in leukemia cells. We analyzed Id1 expression as possible prognostic factor in 237 acute myeloid leukemia (AML) patients.

The JAK2 617V>F mutation triggers erythropoietin hypersensitivity and terminal erythroid amplification in primary cells from patients with polycythemia vera.

The JAK2 617V>F mutation is frequent in polycythemia vera (PV) and essential thrombocythemia (ET). Using quantitative polymerase chain reaction (PCR), we found that high levels of JAK2 617V>F in PV correlate with increased granulocytes and high levels of hemoglobin and endogenous erythroid colony formation. We detected normal progenitors and those that were heterozygous or homozygous for the mutation by genotyping ET and PV clonal immature and committed progenitors.

Multiple signaling pathways are involved in erythropoietin-independent differentiation of erythroid progenitors in polycythemia vera.

Polycythemia vera (PV) is a myeloproliferative disorder arising in a multipotent hematopoietic stem cell. The pathogenesis of PV remains poorly understood; however, the biologic hallmark of this disease is the presence of erythropoietin (Epo)-independent colony formation (endogenous erythroid colony [EEC]) and cytokine hypersensitivity. We have developed a simple liquid culture from CD34+ cells to study PV erythroid differentiation.

Pure red-cell aplasia and antierythropoietin antibodies in patients treated with recombinant erythropoietin.

Background: Within a period of three years, we identified 13 patients in whom pure red-cell aplasia developed during treatment with recombinant human erythropoietin (epoetin). We investigated whether there was an immunologic basis for the anemia in these patients.

Methods: Serum samples from the 13 patients with pure red-cell aplasia were tested for neutralizing antibodies that could inhibit erythroid-colony formation by normal bone marrow cells in vitro.