Evolving patterns of lymphopoiesis from embryogenesis through senescence

Lymphopoiesis occurs throughout adult life, but the number of lymphocytes produced is substantially reduced in old individuals. This commentary will highlight observations suggesting that common mechanisms underlie declines in both B and T cell production and that reductions in lymphopoiesis are initiated much earlier than has generally been appreciated.     

Differentiation syndrome in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline chemotherapy: characteristics, outcome, and prognostic factors

Differentiation syndrome (DS) can be a life-threatening complication in patients with acute promyelocytic leukemia (APL) undergoing induction therapy with all-trans retinoic acid (ATRA). Detailed knowledge about DS has remained limited. We present an analysis of the incidence, characteristics, prognostic factors, and outcome of 739 APL patients treated with ATRA plus idarubicin in 2 consecutive trials (Programa Espa?ol de Tratamientos en Hematología [PETHEMA] LPA96 and LPA99). Overall, 183 patients (24.8%) experienced DS, 93 with a severe form (12.6%) and 90 with a moderate form (12.2%). Severe but not moderate DS was associated with an increase in mortality. A bimodal incidence of DS was observed, with peaks occurring in the first and third weeks after the start of ATRA therapy. A multivariate analysis indicated that a WBC count greater than 5 x 10(9)/L and an abnormal serum creatinine level correlated with an increased risk of developing severe DS. Patients receiving systematic prednisone prophylaxis (LPA99 trial) in contrast to those receiving selective prophylaxis with dexamethasone (LPA96 trial) had a lower incidence of severe DS. Patients developing severe DS showed a reduced 7-year relapse-free survival in the LPA96 trial (60% vs 85%, P = .003), but this difference was not apparent in the LPA99 trial (86% vs 88%).     

In vitro leukemic cell differentiation and WT1 gene expression

Cell differentiation and four WT1 isoforms were assessed in CD34(+) cells from patients with acute myelogenous leukemia in presence or absence of recombinant human GM-CSF and G-CSF, on days 0, 10 and 20 of culture. We found that WT1 isoforms expression was consistently higher in AML-derived CD34+ cell-enriched cell fractions, as compared to their normal counterparts, and interestingly, in both cases, cells had differentiation towards the myeloid lineage with WT1 expression different patterns. This data suggest that WT1 expression seems to be modulated by the presence of cytokines, especially on day 20 of culture.     

Burden of atopic dermatitis in Asia

Atopic dermatitis is a chronic, inflammatory skin disease characterized by intense pruritus and eczematous lesions. It is considered one of the most common chronic conditions, with an estimated global prevalence of nearly 230 million. As in the rest of the world, prevalence of atopic dermatitis has been increasing in Asian countries over the last few decades. This increased prevalence in Asian countries has been attributed to factors such as rapid urbanization, increasingly Westernized lifestyles, and improved standards of living and education. As a result, it is important to understand the increasing burden of disease in Asian countries and the differences between the countries in terms of epidemiology, diagnostic criteria, management, quality of life and economic burden.