A targeted monitoring strategy among patients at a high risk of EBV-associated PTLD might be helpful to decrease the risk of development of PTLD. However, larger prospective studies are needed to verify this hypothesis.

Leukocyte depletion (LD) by blood product filtration has been shown to be similarly effective to the use of screened, CMV seronegative blood products to prevent CMV disease in CMV seronegative allogeneic stem cell transplant (SCT) patients with CMV seronegative donors. The aim of this retrospective study was to determine the risk for development of CMV infection requiring preemptive therapy and for CMV disease if unscreened products treated by prestorage LD is used. Forty-nine consecutive patients transplanted after June 1995 were included. As a control group, 33 patients transplanted from January 1992 to June 1995 in whom a combination of CMV seronegative and LD blood products were given. All patients were monitored weekly by a leukocyte-based PCR for CMV DNA detection. Preemptive therapy was initiated after two consecutively positive tests. No patient developed CMV disease in either group. CMV DNA was detected in 6/49 (p = NS) in the study group and in 3/33 patients in the historical control group. Two patients in the study group were given preemptive therapy compared to one patient in the control group. This study suggests that the risk for CMV disease and the need for preemptive therapy against CMV is low in CMV seronegative allogeneic SCT patients receiving grafts from CMV seronegative stem cell donors receiving LD blood products. Thus, this strategy can be safely used together with PCR monitoring and preemptive therapy.

BackgroundInterleukin 7 (IL-7) signals via the IL-7 receptor (IL-7R) and drives homeostatic T-cell proliferation in patients after allogeneic hematopoietic stem cell transplantation (aHSCT).PurposeWe performed a prospective study in adults (n = 33) and children (n = 29) undergoing aHSCT measuring plasma IL-7 and soluble IL-7R (sIL-7R) concentrations between 1 and 12 months after HSCT in order to investigate the link between sIL-7R and clinical events after aHSCT.ResultssIL-7R, but not IL-7, increased with time after HSCT in plasma from all patients enrolled in the study. sIL-7R values were higher at 2, 3, and 6 months (p < 0.01) if the donor was a sibling as compared to an unrelated donor. Increased sIL-7R levels were also identified in plasma from patients who were not treated with anti-thymocyte globulin (ATG). Low sIL-7R was associated with any grade of acute graft-versus-host disease (GVHD) at 2 and 6 months (p = 0.02) and with a positive CMV PCR at 2 months after HSCT (p < 0.05). Patients with cytomegalovirus (CMV) reactivation had increased IL-7 values at 2 and 3 months (p = 0.02) after HSCT. In multivariate analysis, lower sIL-7R levels were associated with acute GVHD (relative hazard (RH): 0.70, p > 0.01) and sibling donors (RH: 2.23, p = 0.004). Recipients of sibling grafts showed high levels of IL-7 (RH: 1.38, p < 0.05) and bone marrow recipients had low IL-7 levels (RH: 0.73, p = 0.04).ConclusionsMeasurement of the sIL-7R/IL-7 axis will help in guided immune monitoring after HSCT and guided interference with sIL-7R may be explored in GVHD management.

The level of Epstein-Barr virus DNA in blood has proven to be a biomarker with some predictive value in allogeneic hematopoietic stem cell transplantation patients (HSCT). We evaluated the impact of EBV load on survival of 51 patients (32M/19F, median age: 32 years, from < 1 to 68 years old), who had received HSCT for different types of malignancies (49 cases) or non-malignancies (2 cases). The overall survival [1]was compared between patients with extreme and moderate cell bound EBV DNA levels. Different sources of stem-cells (peripheral blood stem, n = 39; bone marrow, n = 9; or umbilical cord blood, n = 3) were used. Twenty patients received reduced-intensity conditioning regimen while the other 31 received myeloablative conditioning. Patients with high or very low level of cell bound EBV-DNA levels had a shorter OS than those with moderate EBV load: OS at 5 years was 67% vs 90% (p < 0.03). There was a conspicuous relationship between EBV load and the reconstitution dynamics of total and EBV-specific T cells, CD4+ and CD4- CD8- (double negative) T cells in the few patients where it was analyzed. This was not statistically significant. Two other factors were associated to early mortality in addition to high or low EBV load: acute GVHD II-IV (p < 0.02) and pre-transplant conditioning with total body irradiation (TBI) ≥6 Gy, (p < 0.03). All the patients meeting all three criteria died within two years after transplantation. This points to a subgroup of HSCT patients which deserve special attention with improvement of future, personalized treatment.

At present, the literature on the efficacy and risks of i.t. chemotherapy to children after HSCT is scarce. Current practices to reduce the risk of leukemic relapse in the CNS after HSCT differ between centers of transplantation. We compared 74 patients (56 ALL/18 AML), who received i.t. therapy post-HSCT with 46 patients (36 ALL/10 AML) who did not receive post-HSCT i.t. therapy. The patients were transplanted at the University Children's Hospital, Uppsala or the Karolinska University Hospital, Huddinge, two Swedish transplantation units with different routines concerning i.t. therapy after HSCT. The primary end-point was the number of isolated CNS relapses. Secondary end-points were other types of relapse, death, and neurological complications. There was no statistically significant difference in the incidence of CNS relapses between the groups (p > 0.05). I.t. therapy did not reduce the overall incidence of isolated CNS relapse or mortality. Our study did not demonstrate a protective effect of i.t. therapy indicating that post-HSCT i.t. therapy may only be of limited use in the treatment of acute childhood leukemia. We conclude that with the risks present, i.t. therapy should be carefully evaluated, and only considered in high-risk cases.