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The article discusses research which investigated the effectiveness of lenalidomide in treating patients with myelodysplastic syndromes (MDS) associated with partial chromosome 5 deletion. Topics explored include the classification of MDS according to the World Health Organization (WHO), the patients' response to treatment in terms of absolute neutrophil count and platelet count, and the clinical characteristics of patients involved in the study.

Alloantibody tests demonstrate immunological causes of insufficient increments in random platelet transfusions. The value of a positive or negative test result in predicting the outcome of human leucocyte antigen (HLA)-matched transfusions in patients refractory to leucodepleted random platelet transfusions has not been assessed. We retrospectively evaluated the outcome of the first HLA-matched platelet transfusion in 72 patients with haematological diseases in two ways: first, the strategy according to which the patient was selected for HLA-matched platelet transfusions was analysed. The strategies were: (i) results of alloantibody tests were not available, (ii) a positive alloantibody test, (iii) a negative alloantibody test. Secondly, the outcome of the first HLA-matched transfusion was investigated relative to the results of alloantibody tests, irrespective of the decision strategy. No significant association was found between the decision strategy and the outcome of the first HLA-matched platelet transfusion. Positive alloantibody tests, however, predicted a better outcome of the first HLA-matched platelet transfusion ( P = 0·04 and P = 0·03 after 1 and 16 h respectively). In patients refractory to random platelet transfusions, positive alloantibody tests predicted a better outcome of HLA-matched platelet transfusions. Patients with negative alloantibody tests, however, may benefit from HLA-matched platelet transfusions. [ABSTRACT FROM AUTHOR]

Summary. We describe the characterization of a novel 7·9 kb deletion that eliminated one of the duplicated α-globin genes, causing an α+ -thalassaemia phenotype in two independent carriers of Suriname–Indian origin. The molecular characterization of the deletion breakpoint fragment revealed neither involvement of Alu repeat sequences nor the presence of homologous regions prone to recombination, suggesting a non-homologous recombination event. This α+ -thalassaemia deletion was found to give rise to an atypical haemoglobin H (HbH) disease characterized by a non-transfusion-dependent moderate microcytic hypochromic anaemia in combination with a poly adenylation signal mutation of the α-globin gene (α2 AATAAA → AATA-- --). [ABSTRACT FROM AUTHOR]

T-cell prolymphocytic leukemia (T-PLL) is mostly characterized by aberrant expansion of small- to medium-sized prolymphocytes with a mature post-thymic phenotype, high aggressiveness of the disease and poor prognosis. However, T-PLL is more heterogeneous with a wide range of clinical, morphological, and molecular features, which occasionally impedes the diagnosis. We hypothesized that T-PLL consists of phenotypic and/or genotypic subgroups that may explain the heterogeneity of the disease. Multi-dimensional immuno-phenotyping and gene expression profiling did not reveal clear T-PLL subgroups, and no clear T-cell receptor a or β CDR3 skewing was observed between different T-PLL cases. We revealed that the expression of microRNA (miRNA) is aberrant and often heterogeneous in T-PLL. We identified 35 miRNA that were aberrantly expressed in T-PLL with miR-200c/141 as the most differentially expressed cluster. High miR- 200c/141 and miR-181a/181b expression was significantly correlated with increased white blood cell counts and poor survival. Furthermore, we found that overexpression of miR-200c/141 correlated with downregulation of their targets ZEB2 and TGFβR3 and aberrant TGFβ1- induced phosphorylated SMAD2 (p-SMAD2) and p-SMAD3, indicating that the TGFβ pathway is affected in T-PLL. Our results thus highlight the potential role for aberrantly expressed oncogenic miRNA in T-PLL and pave the way for new therapeutic targets in this disease.

B-cell prolymphocytic leukemia (B-PLL) is a rare mature B-cell malignancy that may be hard to distinguish from mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL). B-PLL cases with a t(11;14) were redefined as MCL in the World Health Organization 2008 classification. We evaluated 13 B-PLL patients [7 being t(11;14)-positive (B-PLL+) and 6 negative (B-PLL-)] and compared them with MCL and CLL patients. EuroFlow-based immunophenotyping showed significant overlap between B-PLL+ and B-PLL-, as well as between B-PLL and MCL, whereas CLL clustered separately. Immunogenotyping showed specific IGHV gene usage partly resembling MCL. Gene expression profiling showed no separation between B-PLL+ and B-PLL- but identified 3 subgroups. One B-PLL subgroup clustered close to CLL and another subgroup clustered with leukemic MCL; both were associated with prolonged survival. A third subgroup clustered close to nodal MCL and was associated with short survival. Gene expression profiles of both B-PLL+ and B-PLL- showed best resemblance with normal immunoglobulin M-only B-cells. Our data confirm that B-PLL+ is highly comparable to MCL, indicate that B-PLL- also may be considered as a specific subgroup of MCL, and suggest that B-PLL is part of a spectrum, ranging from CLL-like B-PLL, to leukemic MCL-like B-PLL, to nodal MCL-like B-PLL., (© 2014 by The American Society of Hematology.)

Patients with type 2 and 3 von Willebrand disease (VWD) are treated with factor VIII/VWF concentrate in case of bleeding or surgery. Immunate (Baxter, Vienna, Austria) is a double virus inactivated FVIII/VWF concentrate and is registered in several countries for patients with VWD with reduced FVIII levels. We performed an in vitro, a pharmacokinetic and a clinical study to evaluate Immunate in VWD. In vitro studies showed a significant variation in VWF levels in 9 different batches. The median (range) values (in IU/mL) were 1.10 (0.98-1.30) for FVIII:C, 1.34 (0.95-1.61) for VWF:Ag, 0.60 (0.27-1.08) for VWF:CBA and 0.73 (0.59-0.94) for VWF:RCo. The relatively low VWF activity is mainly due to the lack of high molecular weight multimers (HMWM), as determined by electrophoresis. A pharmacokinetic study showed, based on a content of FVIII:C of 1 U/mL, in vivo recoveries (%) of 106 (56-150) (median and range) for FVIII:C, 105 (62-187) for VWF:Ag, 25 (7-41) for VWF:CBA and 43 (11-76) for VWF:RCo. Half-lives were 14.1 h (7.4-36.9) for FVIII:C, 10.8 h (7.7-26.2) for VWF:Ag, 15.3 h (7.8-44.6) for VWF:CBA and 16.4 h (4.2-26.5) for VWF:RCo. In a clinical study efficacy was determined after infusion given before surgery or dental extractions in ten patients. In two patients the hemostatic response was classified as inadequate. In conclusion, there is a wide variability in VWF concentration and activity in various batches of Immunate. In the clinical study in which the dosage was based on FVIII:C contents of the concentrate, two out of ten patients had an insufficient haemostatic response. Therefore dosing of Immunate dosing should not be based on FVIII:C levels, but should be based on VWF activity of the individual batches. Future studies using a VWF activity-guided dosage regimen have to be performed to establish the efficacy of Immunate in the treatment of von Willebrand disease.

We describe the characterization of a novel 7.9 kb deletion that eliminated one of the duplicated alpha-globin genes, causing an alpha+-thalassaemia phenotype in two independent carriers of Suriname-Indian origin. The molecular characterization of the deletion breakpoint fragment revealed neither involvement of Alu repeat sequences nor the presence of homologous regions prone to recombination, suggesting a non-homologous recombination event. This alpha+-thalassaemia deletion was found to give rise to an atypical haemoglobin H (HbH) disease characterized by a non-transfusion-dependent moderate microcytic hypochromic anaemia in combination with a poly adenylation signal mutation of the alpha-globin gene (alpha2 AATAAA --> AATA-- --).