The frequency of JAK2 V617F mutation, expression level of phosphorylated JAK/STATs proteins and their clinical significance in myeloproliferative disorders patients / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the frequency of JAK2 V617F mutation in 145 myeloproliferative disorders (MPDs) patients, analyze the correlation between JAK2 V617F mutation and clinical features.</p><p><b>METHODS</b>The JAK2 V617F mutation was detected by direct DNA sequencing of PCR product and allele-specific PCR respectively. The expression of JAK2, phospho-JAK2 and phospho-STAT5 proteins was determined by Western blot. The clinical data of MPDs patients with or without JAK2 V617F mutation was collected and analyzed for evaluating the clinical significance of JAK2 V617F mutation.</p><p><b>RESULTS</b>1) The frequency of JAK2 V617F mutation for PV, IMF, ET was 92%, 58%, 50% respectively. Compared with conventional DNA sequencing (PV 84%, IMF 44%, ET 39%, respectively), allele-specific PCR exhibited a higher sensitivity in JAK2 V617F mutation detection. 2) The expression levels of phospho-JAK2 and phospho-STAT5 in peripheral blood mononuclear cells (PBMNCs) were upregulated significantly in JAK2 V617F-positive patients than in JAK2 V617F negative patients. 3) Compared with the patients with no JAK2 V617F mutation, the JAK2 V 617F-positive patients' features were as follows: older age of onset, higher mean leukocyte counts, lower platelet counts and smaller spleen volume. Frequency of thrombosis events in PT, ET, IMF was 17%, 32%, 16% respectively for JAK2 V617F positive group, and 0% (PV), 16% (ET), 5% (IMF) for JAK2 V617F negative group.</p><p><b>CONCLUSIONS</b>MPDs patients display higher frequency of JAK2 V617F mutation. JAK2 V617F mutation positive patients predispose to a thrombosis tendency.</p>

In vitro anti-myeloma effects induced by myeloma idiotype-protein pulsed dendritic cell vaccine / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the specific antitumor immune response induced by idiotype protein (Id)-pulsed dendritic cells (DC) in vitro.</p><p><b>METHODS</b>DC was generated from peripheral blood monocytes of the multiple myeloma (MM) patients using GM-CSF, IL-4, and TNF-alpha. The DCs were pulsed with idiotypic fragment, the F(ab')2 fragment of M protein from MM patient at the immature stage. The morphologic characteristics of the cells were observed with light and electron microscopes. The phenotypic features were analyzed with FACS, MTT assay was employed to evaluate the proliferation of autologous T cells and the inhibition rate of MM cells.</p><p><b>RESULTS</b>DC precursors in peripheral blood could be induced to typical mature DC in medium containing GM-CSF, IL-4 and TNF-alpha. Mature DC with Id could increase the proliferation of the autologous T cells and activate naive T cells to become tumor specialized cytotoxic T lymphocytes (CTL). The CTL at different doses showed significant inhibition on or killing ability to autologous MM cells in vitro.</p><p><b>CONCLUSIONS</b>In a suitable cytokine environment, the DC precursors from peripheral blood of MM patients could be induced to functional DC, and vaccination of Id-pulsed DC could induce active antitumor immune response.</p>