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Background and Objectives: After allogeneic haematopoietic stem cell transplantation (SCT) the whole T-cell receptor (TCR) repertoire shows a markedly skewed pattern for 2-3 years. A small fraction of CD4+ T cells is represented by CD25+ regulatory lymphocytes (Treg), which play a crucial role in modulating peripheral tolerance. To investigate their ability to react to the massive antigenic stimulation generated in an allogeneic host, which could significantly affect their pattern of reconstitution, we analyzed the TCR repertoire of Treg after SCT, focusing on the degree of similarity to CD4+CD25- conventional T cells (Tconv)., Design and Methods: We assessed the TCR Vbeta repertoire of Treg in ten patients who had received allogeneic SCT, by using complementarity determining region 3 (CDR3) spectratyping. We developed a new similarity score for the analysis. This score expresses the proportion of Vbeta with similar profile between Treg and Tconv., Results: For up to 3 years after SCT the repertoires of Treg and Tconv were characterized by several Vbeta with different profiles between the two cell subsets, while they were extremely similar in patients more than 3 years post-allografting (similarity score= 0.90 vs. 0.61). The differences observed early after SCT were mainly ascribable to Vbeta expressing an oligoclonal profile in Tconv but not in Treg., Interpretation and Conclusions: Our data show that the TCR repertoires of Treg and Tconv are significantly different early post-SCT, while they tend to become identical with full reconstitution. This difference could reflect either a discrepancy in the in vivo reactivity against common antigenic stimulations or be the result of different post-transplant ontogeny.

In this study we determined the levels of circulating soluble transferrin receptor (sTfR) in six untransfused and two transfused patients affected by beta-thalassemia intermedia during low-dose rHuEPO administration. While the majority of the untransfused patients showed a temporary increment during the first month of treatment, a higher and enduring increase in sTfR concentration was observed in the two transfused patients until rHuEPO was discontinued. The transfused patients showed a significant increase in the reticulocyte index together with the rise in sTfR and an improvement of the anemia, as evidenced by the decrease in their transfusional requirement. These data suggest that basal erythropoietic activity is one of the main causes of differences in responsiveness to low doses of rHuEPO given in thalassemia intermedia.

In this study we determined serum IL-8 levels in 18 untransfused patients with beta-thalassemia intermedia and in 14 subjects affected by HbH disease. As reported in polytransfused homozygous beta-thalassemia, untransfused beta-thalassemia and HbH disease show significantly (p < 0.005) higher serum IL-8 levels than normal controls. Our data suggests that there could be an intrinsic cause for the IL-8 increase in thalassemia intermedia. We think than the hyperactivity of thalassemic macrophages related to chronic hemolysis is the main cause for the increment in cytokines, such as IL-8, found in thalassemic syndromes.

Seventy months after diagnosis, minimal residual disease is undetectable in a patient with Philadelphia chromosome-positive chronic myelogenous leukemia (CML) in long-lasting continuous cytogenetic conversion (CCC), achieved through alpha 2a-interferon (IFN-alpha) therapy. Fluctuating molecular remission, evaluated with the two-stage reverse transcriptase-polymerase chain reaction (RT-PCR) with nested primers, has persisted for two years at the maximum tolerable dose of IFN alpha (1.5 x 10(6) IU per day).