Cytomegalovirus (CMV) disease and infection refractory to antiviral treatment after allogeneic stem cell transplantation (allo-SCT) is associated with a high mortality. Adoptive transfer of CMV-specific T cells could reconstitute viral immunity after SCT and could protect from CMV-related complications. However, logistics of producing virus-specific T-cell grafts limited the clinical application. We treated 18 patients after allo-SCT from human leukocyte antigen-mismatched/ haploidentical or human leukocyte antigen-matched unrelated donors with polyclonal CMV-specific T cells generated by ex vivo stimulation with pp65, followed by isolation of interferon-␥-producing cells. Patients with CMV disease or viremia refractory to antiviral chemotherapy or both were eligible for adoptive T-cell transfer and received a mean of 21 ؋ 10 3 /kg pp65-specific T cells. In 83% of cases CMV infection was cleared or viral burden was significantly reduced, even in cases of CMV encephalitis (n ‫؍‬ 2). Viral control was associated with in

SummaryDuring periods of immunosuppression, such as postallogeneic stem cell transplantation (SCT), patients are at significant risk for severe viral infections. Human adenovirus (HAdV) infection is a serious complication post‐SCT, especially in children. Virus‐specific T cells are essential for the clearance of HAdV, as antiviral chemotherapy has revealed limited success. We present feasibility data for a new treatment option using virus‐specific donor T cells for adoptive transfer of immunity to patients with HAdV‐infection/reactivation. Virus‐specific donor T cells were isolated and infused into nine children with systemic HAdV infection after SCT. Isolation was based on γ‐interferon (IFN‐γ) secretion after short in vitro stimulation with viral antigen, resulting in a combination of CD4+ and CD8+ T cells. 1·2–50 × 103/kg T cells were infused for adoptive transfer. Isolated cells showed high specificity and markedly reduced alloreactivity in vitro. Adoptive transfer of HAdV‐specific immunity was successful in five of six evaluable patients, documented by a dose‐independent and sustained in vivo expansion of HAdV‐specific T cells, associated with a durable clearance/decrease of viral copies. T‐cell infusion was well tolerated in all nine patients, except one case with graft‐versus‐host disease II of the skin. In conclusion, induction of a specific T‐cell response through adoptive transfer was feasible and effective. When performed early in the course of infection, adoptive T‐cell transfer may protect from HAdV‐related complications.

Infertility is a major late effect in patients receiving haematopoietic stem cell transplantation (HSCT). The aim of this study was to determine the proportion of patients having fertility impairment after allogeneic HSCT in childhood/adolescence and to identify the potential risk factors. Treatment and fertility data of paediatric patients with malignant and non-malignant diseases treated with allogeneic HSCT between 2000 and 2005 were collected from seven European centres. Data were obtained for 138 female and 206 male patients after a median follow-up of 6 years (range 3-12). The patients' median age was 13 years (range 4-28) at the time of years at the time of the enquiry. Seven children were born to the overall group, all at term and healthy. Fertility impairment was suspected in 69% males and 83% females. Start of treatment at age X13 years was a risk factor in females (odds ratio (OR) 4.7; 95% confidence interval (CI), 1.5 to 14.9), whereas pre-pubertal therapy was a risk factor in males (OR 0.4; 95% CI, 0.2 to 0.8). The major treatment-related risk factors were BU in females (OR 47.4; 95% CI, 5.4 to 418.1) and TBI in males (OR 7.7; 95% CI, 2.3 to 25.4). In light of the significant proportion of HSCT patients reviewed with impaired fertility, fertility conservation procedures should be considered for all patients undergoing HSCT, particularly those receiving TBI or BU-based preparative regimens.

Key Points Adoptive transfer of TH-1 cells is a safe and effective treatment of refractory AdV infection after stem cell transplantation. AdV-related mortality was 9.5% in patients with a response to ACT (overall survival 71%) compared with 100% mortality in nonresponders.

Key Points• Lowest numbers of ex vivo-selected CD8 1 memory T cells can reconstitute pathogen-specific immunity in immunocompromised hosts.Patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) are threatened by potentially lethal viral manifestations like cytomegalovirus (CMV) reactivation. Because the success of today's virostatic treatment is limited by side effects and resistance development, adoptive transfer of virus-specific memory T cells derived from the stem cell donor has been proposed as an alternative therapeutic strategy. In this context, dose minimization of adoptively transferred T cells might be warranted for the avoidance of graft-versus-host disease (GVHD), in particular in prophylactic settings after T-cell-depleting allo-HSCT protocols. To establish a lower limit for successful adoptive T-cell therapy, we conducted low-dose CD8 1 T-cell transfers in the well-established murine Listeria monocytogenes (L.m.) infection model. Major histocompatibility complex-Streptamer-enriched antigen-specific CD62L hi but not CD62L lo CD8 1 memory T cells proliferated, differentiated, and protected against L.m. infections after prophylactic application. Even progenies derived from a single CD62L hi L.m.-specific CD8 1 T cell could be protective against bacterial challenge. In analogy, low-dose transfers of Streptamerenriched human CMV-specific CD8 1 T cells into allo-HSCT recipients led to strong pathogen-specific T-cell expansion in a compassionate-use setting. In summary, low-dose adoptive T-cell transfer (ACT) could be a promising strategy, particularly for prophylactic treatment of infectious complications after allo-HSCT. (Blood. 2014;124(4):628-637)