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Iron overload in β-thalassemia major (TM) typically results in iron-induced cardiomyopathy, liver disease, and endocrine complications. We examined the incidence and progression of endocrine disorders (hypothyroidism, diabetes, hypoparathyroidism, hypogonadism), growth and pubertal delay, and bone metabolism disease during long-term deferasirox chelation therapy in a real clinical practice setting. We report a multicenter retrospective cohort study of 86 transfusion-dependent patients with TM treated with once daily deferasirox for a median duration of 6.5 years, up to 10 years. No deaths or new cases of hypothyroidism or diabetes occurred. The incidence of new endocrine complications was 7% (P = 0.338, for change of prevalence from baseline to end of study) and included hypogonadism (n = 5) and hypoparathyroidism (n = 1). Among patients with hypothyroidism or diabetes at baseline, no significant change in thyroid parameters or insulin requirements were observed, respectively. Mean lumbar spine bone mineral density increased significantly (P

Impaired switching from fetal haemoglobin (HbF) to adult globin gene expression leads to hereditary persistence of fetal haemoglobin (HPFH) in adult life. This is of prime interest because elevated HbF levels ameliorate β-thalassaemia and sickle cell anaemia. Fetal haemoglobin levels are regulated by complex mechanisms involving factors linked or not to the β-globin gene (HBB) locus. To search for factors putatively involved in the expression of the γ-globin genes (HBG1, HBG2), we examined the reticulocyte transcriptome of three siblings who had different HbF levels and different degrees of β-thalassaemia severity although they had the same ΗBA- and ΗΒB cluster genotypes. By mRNA differential display we isolated the cDNA coding for the cold shock domain protein A (CSDA), also known as dbpA, previously reported to interact in vitro with the HBG2 promoter. Expression studies performed in K562 and in primary erythroid cells showed an inverse relationship between HBG and CSDA expression levels. Functional studies performed by Chromatin Immunoprecipitation and reporter gene assays in K562 cells demonstrated that CSDA is able to bind the HBG2 promoter and suppress its expression. Therefore, our study demonstrated that CSDA is a trans-acting repressor factor of HBG expression and modulates the HPFH phenotype.

There is great interest in mesenchymal stromal cells (MSCs) for cell-therapy and tissue engineering approaches. MSCs are currently expanded in vitro in the presence of fetal calf serum (FCS); however, FCS raises concerns when used in clinical grade preparations. The aim of this study was to evaluate whether MSCs expanded in medium supplemented with platelet-lysate (PL), already shown to promote MSC growth, are endowed with biological properties appropriate for cell-therapy approaches. We confirm previously published data showing that MSCs expanded in either FCS or PL display comparable morphology, phenotype, and differentiation capacity, while PL-MSCs were superior in terms of clonogenic efficiency and proliferative capacity. We further extended these data by investigating the immune-regulatory effect of MSCs on the alloantigen-specific immune response in mixed lymphocyte culture (MLC). We found that MSCs-PL are comparable to MSCs-FCS in their capacity to: (i) decrease alloantigen-induced cytotoxic activity; (ii) favor differentiation of CD4+ T-cell subsets expressing a Treg phenotype; (iii) increase early secretion of IL-10 in MLC supernatant, as well as induce a striking augmentation of IL-6 production. As compared with MSCs-PL, MSCs-FCS were more efficient in suppressing alloantigen-induced lymphocyte subset proliferation and reducing early IFN-γ-secretion. Resistance to spontaneous transformation into tumor cells of expanded MSCs was demonstrated by molecular karyotyping and maintenance of normal morphology/phenotype after prolonged in vitro culture. Our data support the immunological functional plasticity of MSCs and suggest that MSCs-PL can be used as an alternative to MSCs-FCS, although these latter cells might be more suitable for preventing/treating alloreactivity-related immune complications. © 2006 Wiley-Liss, Inc.

This retrospective study was conducted to determine whether the response to splenectomy is related to the response to previous treatments. We examined the records of 90 children splenectomized for chronic ITP. Platelet counts were constantly>50x10(9)/L in 68 patients (75%). An improvement in the quality of life was observed in 79 (85%). The success of splenectomy was strongly correlated with a good response to previous treatment. A negative response to any of the prior treatments had no predictive value. This finding is relevant when elective splenectomy is considered as a treatment option.

The trisomy 8 found in malignancies may derive from a constitutional trisomy 8 mosaicism (CT8M), and in these cases the trisomy itself may be regarded as the first mutation in a multistep carcinogenetic process. To assess the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8, an informative sample of 14 patients was collected. The data ascertained included chromosome analyses of fibroblast cultures and of PHA-stimulated blood cultures in patients with normal blood differential count, as well as possible CT8M clinical signs. One patient showed trisomy 8 in all cell types analyzed and undoubtedly has a CT8M; a second patient consistently showed trisomy 8 in PHA-stimulated blood cultures when no immature myeloid cells were present in blood and should be considered as having CT8M; a third patient, with Philadelphia-positive chronic myelocytic leukemia, was more difficult to interpret, but the possibility that she had CT8M is likely. A few clinical signs of CT8M were also present in these three patients. Our data indicate that the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8 is approximately 15-20%.

Congenital dyserythropoietic anaemia type II (CDA II) is the most common congenital dyserythropoietic anaemia. CDA II is frequently misdiagnosed as Hereditary Spherocytosis (HS) due to the presence of mild chronic haemolytic anaemia with splenomegaly, increased osmotic fragility, and presence of microspherocytes. Accurate diagnosis of CDA II is important to prevent severe iron overload. Erythrocyte and reticulocyte indices were assessed in 10 patients from six families with CDA II, 18 patients from eight families with HS, and 50 normal controls. Characteristic increases in distribution width were present in CDA II for cell volume (RDW, anisocytosis) and in HS for cell haemoglobin concentration (HDW, anisochromia), resulting in an RDW/HDW ratio which was significantly greater in CDA than HS (P < 0.0002). A cut-off value for RDW/HDW of 5.34 resulted in 89% sensitivity and 70% specificity in distinguishing CDA II from HS. Distribution width for cell haemoglobin content of reticulocytes (CHDWr) was characteristically increased in CDA II, resulting in a CHDW/CHDWr ratio significantly lower in CDA II than HS (P < 0.0002). A cut-off value of 0.98 provided 89% sensitivity and 80% specificity in distinguishing CDA II from HS. These differences in distribution widths of flow-cytometric parameters of reticulocytes and mature erythrocytes reflect the different pathogeneses of the two diseases and are helpful for the differential diagnosis of these two conditions.

This report represents an attempt to define the rate of beta-spectrin de novo mutations affecting mRNA accumulation in patients with hereditary spherocytosis (HS). 19 HS children with haematologically normal parents and varying degrees of spectrin deficiency were studied. 13 of the 19 cases who were heterozygous at the genomic level for polymorphisms in the beta-spectrin coding region were further studied. However, in an analysis of reverse-transcripted amplified cDNA from the regions of the polymorphisms, seven patients appeared to be homozygous, suggesting the occurrence of de novo mutational events affecting expression of one beta-spectrin allele. We conclude that in HS patients with isolated spectrin reduction and normal parents the apparently recessive pattern of inheritance may frequently be associated with de novo monoallelic expression of beta-spectrin.

This study describes the clinical phenotype of the C-->T mutation at position -92 of the beta-globin gene. Excluding two cases with HbA2 levels within the range of the beta-thalassemia carrier state, heterozygotes for this mutation showed normal or borderline red blood cells count, Hb levels, MCV, MCH and HbA2 values, and unbalanced globin chain synthesis. Compound heterozygotes for the -92 C-->T mutation and a beta zero-thalassaemia mutation (beta zero 39) (two cases) or severe beta+-thalassaemia (beta+ IVSII nt 745) (two cases) developed thalassaemia intermedia. According to these characteristics, the -92 promoter mutation should be added to the list of silent beta-thalassaemias.

Summary Lipid abnormalities, including low levels of all fractions of serum lipids, have been repeatedly reported in all phenotypes of β-thalassemia. Unexpectedly, in more recent studies, the concentration of total cholesterol (TC) and high- and/or low-density lipoprotein cholesterol (HDL-C and LDL-C) has been found in β-thalassemia intermedia (TI) patients even lower than in thalassemia major, without a clear explanation of pathophysiology of these findings. This lack of information prompted us to evaluate the plasma lipids and lipoproteins pattern in the TI patients followed in our department; the data were compared with those found in hereditary spherocytosis patients. Furthermore, in both groups of patients, the erythroid bone marrow activity was evaluated, utilizing the level of soluble transferrin receptors (sTfR) in the plasma. Both groups of patients showed similar lipid abnormalities (low-TC, HDL-C and LDL-C) and the same increase of sTfR, with significantly lower hemoglobin levels in TI patients. Data analysis of our study shows that the lipid profile in TI patients is not influenced by age, sex, liver injury, hemoglobin or ferritin levels; the higher erythroid bone marrow activity with the enhanced cholesterol consumption could be the dominant mechanism implicated in the lipid abnormalities of TI patients.