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The clinical and haematological phenotype of patients with myelofibrosis harbouring MPL W515 L/ K mutation has not been thoroughly investigated. Of 217 myelofibrosis subjects, 18 (8·2%) had an MPL mutation, four of which (22%) co-existed with JAK2 V617 F mutation. When compared with MPL wild-type patients, irrespective of JAK2 V617 F status, those with MPL W515 L/ K, were more frequently female, were older (61 years vs. 57 years; P = 0·02), presented with more severe anaemia (haemoglobin, 101 g/l vs. 121 g/l; P = 0·002) and were more likely to require regular transfusional support ( P = 0·012). These data indicate that MPL mutation in myelofibrosis characterises patients with more severe anaemic phenotype. [ABSTRACT FROM AUTHOR]

Females with the monoclonal type of essential thrombocythaemia (ET), based on the X-chromosome inactivation pattern (XCIP), have previously been shown to present a higher incidence of thrombosis than polyclonal ones. We aimed to assess correlations between XCIP, thrombosis, and three epigenetic markers of ET, namelyPRV-1overexpression, endogenous erythroid colony (EEC) formation, and reduced platelet Mpl content. Fifty-three (60%) of 88 subjects studied had monoclonal myelopoiesis and presented a 32% incidence of major thrombosis compared with 6% of polyclonal subjects (P = 0·009). The frequency of abnormalities ofPRV-1, EEC, or Mpl was similar in monoclonal and polyclonal subjects (respectively, 28%, 48%, 75%, and 37%, 27%, 63%), and none of them correlated with thrombosis. We conclude that the exploited epigenetic markers constitute independent phenotypic variations and are not clustered according to monoclonality of myelopoiesis in ET; none of them could serve as a surrogate marker of thrombotic risk in male subjects with ET. [ABSTRACT FROM AUTHOR]

Adoptive transfer of ex vivo-generated cytomegalovirus (CMV)-specific T lymphocytes may be effective in preventing CMV disease in allogeneic haematopoietic stem cell transplantation (HSCT) recipients. We developed a procedure for expansion of CMV-specific T lymphocytes based on the antigen-presenting function of donor dendritic cells (DCs), pulsed with a human leucocyte antigen A*0201-restricted pp65 nonamer peptide. CMV-specific T lymphocytes were identified following induction of interferon γ (IFN-γ) secretion prompted by peptide exposure. Both CD8+ and CD4+ CMV-specific T lymphocytes were selectively produced in these cultures and showed CMV-restricted cytotoxicity. The simultaneous and selective expansion of CD4+ and CD8+ CMV-specific lymphocytes might be instrumental for more efficient in vivo function of infused CMV-specific lymphocytes. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Inconsistencies in the Association Between the JAK2V617F Mutation and PRV-1 Over-Expression Among the Chronic Myeloproliferative Diseases," published in the 2005 issue.

The clinical and haematological phenotype of patients with myelofibrosis harbouring MPL(W515L/K) mutation has not been thoroughly investigated. Of 217 myelofibrosis subjects, 18 (8.2%) had an MPL mutation, four of which (22%) co-existed with JAK2(V617F) mutation. When compared with MPL wild-type patients, irrespective of JAK2(V617F) status, those with MPL(W515L/K), were more frequently female, were older (61 years vs. 57 years; P = 0.02), presented with more severe anaemia (haemoglobin, 101 g/l vs. 121 g/l; P = 0.002) and were more likely to require regular transfusional support (P = 0.012). These data indicate that MPL mutation in myelofibrosis characterises patients with more severe anaemic phenotype.