T cell reconstitution in allogeneic haematopoietic stem cell transplantation: prognostic significance of plasma interleukin-7.

Infections and acute graft-versus-host disease (aGVHD) are major causes of treatment-related mortality and morbidity following allogeneic haematopoietic stem cell transplantation (HSCT). Both complications depend on reconstitution of the T-lymphocyte population based on donor T cells. Although it is well established that Interleukin-7 (IL-7) is a cytokine essential for de novo T cell development in the thymus and homoeostatic peripheral expansion of T cells, associations between circulating levels of IL-7 and T cell reconstitution following HSCT have not been investigated previously. We prospectively measured IL-7 levels in 81 patients undergoing myeloablative HSCT with either sibling donor or an unrelated donor. Plasma IL-7 levels peaked at day +7 post-transplant (1.3-82.4 pg/ml), at the time of maximal lymphopaenia. In multivariate analysis, peak levels of IL-7 were significantly higher in patients treated with anti-thymocyte globulin (ATG) compared with those not treated with ATG (P = 0.0079). IL-7 levels at day +7 were negatively associated with T cell counts at day +30 to +60 (at day +60: CD3(+) : ß = -10.6 × 10(6) cells/l, P = 0.0030; CD8(+) : ß = -8.4 × 10(6) cells/l, P = 0.061; CD4(+) : ß = -2.1 × 10(6) cells/l, P = 0.062) in multivariate analyses. In adults, high IL-7 levels were associated with increased risk of grade II-IV aGVHD (OR = 5.4, P = 0.036) and reduced overall survival (P = 0.046). The present data indicate that high plasma levels of IL-7 in the early post-transplant period are predictive for slow T cell reconstitution, increased risk of aGVHD and increased mortality following HSCT.

Aerobic exercise capacity at long-term follow-up after paediatric allogeneic haematopoietic SCT.

Peak oxygen uptake (VO2peak), a measure of aerobic exercise capacity, predicts mortality and morbidity in healthy and diseased individuals. Our aim was to determine VO2peak years after paediatric allogeneic haematopoietic SCT (HSCT) and to identify associations with baseline patient and donor characteristics, transplantation factors, pulmonary function and self-reported sports activity. In this cross-sectional, population-based study, we measured VO2peak, spirometry and diffusion capacity of the lung (DLCO) 3-10 years post HSCT. Z-scores were calculated by reference values from healthy subjects. Self-reported hours of sports activity were obtained by interview. We included 63 patients (mean age (range) 14.4 (7-24) years). HSCT patients exhibited lower mean VO2peak (-1.42 z-score, 95% confidential interval (-1.7; -1.1)) compared with healthy subjects (P<0.001). Sixteen patients (25%) had VO2peak values <-1.96 z-score. Low VO2peak was associated with reduced forced expiratory volume in 1 s (R(2)=0.11, P=0.009), reduced DLCO/VA (R(2)=0.09, P=0.01) and low physical activity (mean VO2peak z-score inactive group: -2.1 vs most active group: -1.1, P=0.02). No associations between VO2peak and diagnosis, donor type or GvHD were found. Although causes for reduced VO2peak may be multiple, our findings stress the need to focus on physical activity post HSCT to prevent lifestyle diseases and improve quality of life.

Bronchiolitis obliterans after allo-SCT: clinical criteria and treatment options.

Bronchiolitis obliterans (BO) following allogeneic haematopoietic SCT (HSCT) is a serious complication affecting 1.7-26% of the patients, with a reported mortality rate of 21-100%. It is considered a manifestation of chronic graft-versus-host disease, but our knowledge of aetiology and pathogenesis is still limited. Diagnostic criteria are being developed, and will allow more uniform and comparable research activities between centres. At present, no randomised controlled trials have been completed that could demonstrate an effective treatment. Steroids in combination with other immunosuppressive drugs still constitute the backbone of the treatment strategy, and results from our and other centres suggest that monthly infusions of high-dose pulse i.v. methylprednisolone (HDPM) might stabilise the disease and hinder progression. This article provides an overview of the current evidence regarding treatment options for BO and presents the treatment results with HDPM in a paediatric national HSCT-cohort.