Targeted Therapy with Sirolimus and Nivolumab in a Child with Refractory Multifocal Anaplastic Ependymoma

Pediatric ependymoma (EPN) is the third most common central nervous system (CNS) tumor, with 90% arising intracranially. Management typically involves maximal surgical resection and radiotherapy, but patients' outcome is poor. Moreover, there are only a few therapeutical options available for recurrent or refractory disease. In this report, we present the case of a 7-year-old girl with relapsed refractory multifocal grade III EPN who failed conventional treatments and experienced a stable and durable response to the immune checkpoint inhibitor (ICPI) nivolumab in association with the mammalian target of rapamycin (m-TOR) inhibitor sirolimus. This experimental therapy was targeted on immune phenotypical analyses of the patient's last relapse tumor sample, and this procedure should be routinely done to find new possible therapeutical approaches in recurrent solid tumors

High Incidence of Early Human Herpesvirus-6 Infection in Children Undergoing Haploidentical Manipulated Stem Cell Transplantation for Hematologic Malignancies

Human herpesvirus-6 (HHV-6) infection is increasingly recognized among allogeneic hematopoietic stem cell transplantation (HSCT) recipients, with 30% at risk of reactivation in the haploidentical setting. It has been associated with encephalitis, acute graft-versus-host disease, and graft failure. Here we report 2 cohorts of pediatric haploidentical manipulated HSCT in which, despite many differences, HHV-6 reactivation and disease occurred with very high incidence compared with data reported in the literature and represented the main early post-transplant infectious complication compared with other viral, bacterial, or fungal infections. The 2 cohorts were recruited at the pediatric transplant centers of Perugia (n\u202f=\u202f13), Barcelona (n\u202f=\u202f10), and Madrid (n\u202f=\u202f15). All patients received myeloablative conditioning regimens and 2 different types of ex vivo graft manipulation: CD34+ selection and regulatory T cell/conventional T cell infusion in 13 patients and CD45RA T cell depletion in 25 patients. Antiviral prophylaxis was acyclovir in 33 and foscarnet in 5 patients. HHV-6 DNAemia was checked by quantitative or qualitative PCR. In vitro experiments demonstrated that donor CD4+ T cells are the reservoir of HHV-6 and suggested a role of the graft composition in both transplant settings (rich in CD4+ T cells) in the high rate of HHV-6 infections. All patients presented very early HHV-6 DNAemia after transplantation, and although viremic, 9 patients (24%) developed symptomatic limbic encephalitis. All patients responded to antiviral treatment, and none died of infection, although 2 experienced long-term neurologic sequelae (22%). Moreover, 6 patients presented organ involvement in absence of other causes: 1 hepatitis, 1 pneumonia, 2 gastroenteritis, and 2 multiorgan involvement(1 encephalitis, pneumonia, and gastritis; 1 pneumonia and enteritis). Incidences of other viral, bacterial, and fungal diseases were lower in both cohorts. In vitro, HHV-6 was found to infect only CD4+ fraction of the graft. Co-culturing CD4+ T cells with CD56+ natural killer (NK) cells eliminated the virus, demonstrating the main role of NK cells in the antiviral immune response. All 38 pediatric patients undergoing these manipulated haploidentical HSCTs showed HHV-6 reactivation, and 14 of 38 developed HHV-6 disease with similar features in terms of timing, morbidity, response to treatment, and outcome. The graft composition in both transplant platforms, rich in CD4+ T cells and poor in NK cells, seems to play a key role. HHV-6 DNAemia surveillance was useful to diagnose and treat preemptively HHV-6 infection

Impact of Human Herpes Virus (HHV)-6 infection in manipulated haploidentical stem cell transplantation in children

Retrospective study of HHV-6 infection and disease after haploidentical stem cell transplan

Haploidentical hematopoietic transplantation from KIR ligand-mismatched donors with activating KIRs reduces nonrelapse mortality

Because activating killer cell immunoglobulinlike receptors (KIRs) are heterogeneously expressed in the population, we investigated the role of donor activating KIRs in haploidentical hematopoietic transplants for acute leukemia. Transplants were grouped according to presence vs absence of KIR-ligand mismatches in the graft-vs-host direction (ie, of donor-vs-recipient natural killer [NK]-cell alloreactivity). In the absence of donor-vs-recipient NK-cell alloreactivity, donor activating KIRs had no effects on outcomes. In the 69 transplant pairs with donor-vs-recipient NK-cell alloreactivity, transplantation from donors with KIR2DS1 and/or KIR3DS1 was associated with reduced risk of nonrelapse mortality, largely infection related (KIR2DS1 present vs absent: hazard ratio [HR], 0.25; P = .01; KIR3DS1 present vs absent: HR, 0.18; P = .006), and better event-free survival (KIR2DS1 present vs absent: HR, 0.31; P = .011; KIR3DS1 present vs absent: HR, 0.30; P = .008). Transplantation from donors with KIR2DS1 and/or KIR3DS1 was also associated with a 50% reduction in infection rate (P = .003). In vitro analyses showed that KIR2DS1 binding to its HLA-C2 ligand upregulated inflammatory cytokine production by alloreactive NK cells in response to infectious challenges. Because ∼40% of donors able to exert donor-vs-recipient NK-cell alloreactivity carry KIR2DS1 and/or KIR3DS1, searching for them may become a feasible, additional criterion in donor selection

HLA-haploidentical transplantation with regulatory and conventional T-cell adoptive immunotherapy prevents acute leukemia relapse

Posttransplant relapse is still the major cause of treatment failure in high-risk acute leukemia. Attempts to manipulate alloreactive T cells to spare normal cells while killing leukemic cells have been unsuccessful. In HLA-haploidentical transplantation,we reported that donor-derived T regulatory cells (Tregs), coinfused with conventional T cells (Tcons), protected recipients against graft-versus-host disease (GVHD). The present phase 2 study investigated whether Treg-Tcon adoptive immunotherapy prevents post-transplant leukemia relapse. Forty-three adults with high-risk acute leukemia (acute myeloid leukemia 33; acute lymphoblastic leukemia 10) were conditioned with a total body irradiation–based regimen. Grafts included CD341 cells (mean 9.7 3 106 /kg), Tregs (mean 2.5 3 106/kg), and Tcons (mean 1.1 3 106 /kg). No posttransplant immunosuppression was given. Ninety-five percent of patients achieved full-donor type engraftment and 15% developed ‡grade 2 acute GVHD. The probability of disease-free survival was 0.56 at a median follow-up of 46 months. The very low cumulative incidence of relapse (0.05)was significantly better than in historical ical controls. These results demonstrate the immunosuppressive potential of Tregs can be used to suppress GVHD without loss of the benefits of graft-versus-leukemia (GVL) activity. Humanized murine models provided insights into the mechanisms underlying separation of GVL from GVHD, suggesting the GVL effect is due to largely unopposed Tcon alloantigen recognition in bone marrow. he benefits of graft-versus-leukemia (GVL) activity. Humanized murine models provided eparation of GVL fromGVHD, suggesting theGVL effect is due to largely unopposed Tcon Blood. 2014;124(4):638-644

Initial Results of Peripheral-Blood Stem-Cell Mobilization, Collection, Cryopreservation, and Engraftment After Autologous Transplantation Confirm That the Capacity-Building Approach Offers Good Chances of Success in Critical Contexts: A Kurdish-Italian Cooperative Project at the Hiwa Cancer Hospital, Sulaymaniyah

Introduction: At Hiwa Cancer Hospital (Sulaymaniyah, Iraqi Kurdistan) after the center was started by a cooperative project in June 2016, autologous transplantation was developed. Patients and Methods: To develop the project, the capacity-building approach was adopted, with on-site training and coaching of personnel, educational meetings, lectures, on-the-job training, and the implementation of quality management planning. Results: Here, we report initial results of peripheral-blood stem-cell mobilization and collection of the first 27 patients (age 12 to 61 years; 19 males and 8 females; multiple myeloma, n = 10; plasma cell leukemia, n = 1; Hodgkin lymphoma, n = 12; non-Hodgkin lymphoma, n = 3; and acute myeloid leukemia, n = 1). Only three (11.5%) of 26 patients experienced a failure of mobilization. A median of 6.1 × 106/kg CD34-positive cells per patient were collected (range, 2.4 to 20.8), with two apheretic runs. Twenty-four patients underwent autologous transplantation. All but one transplantation engrafted fully and steadily, with 0.5 and 1.0 × 109/L polymorphonucleates on day 10.5 (range, 8 to 12) and day 11 (range, 9 to 15), respectively, and with 20 and 50 × 109/L platelets on day 13 (range, 10 to 17) and day 17 (range, 2 to 44), respectively. More than 95% of patients are projected to survive 1 year after autograft. Conclusion: These data are the result of an Italian effort to establish in Iraqi Kurdistan a leading center for hemopoietic stem-cell transplantation. The capacity building approach was used, with on-site training and coaching as instruments for the development of provider ability and problem solving. With future limitations for immigration, this method will be helpful, especially in the field of high-technology medicine

Beneficial role of CD8+T-cell reconstitution after HLA-haploidentical stem cell transplantation for high-risk acute leukaemias:results from a clinico-biological EBMT registry study mostly in the T-cell-depleted setting

HLA-haploidentical haematopoietic stem cell transplantation (haplo-HSCT) is increasingly offered to patients with high-risk acute leukaemia. Unfortunately, haplo-HSCT is followed by a delayed immunoreconstitution. The aim of this EBMT registry study was to explore the clinical impact of lymphocyte subset counts after haplo-HSCT. We considered 144 leukaemic patients transplanted in the period 2001-2012. Pre-transplantation clinical variables and differential immune-cell counts (CD3, CD4, CD8 T cells, NK and B cells) measured before day 100 were evaluated for their capacity to predict overall survival, relapse mortality or non-relapse mortality (NRM). Negative prognostic factors for overall survival were advanced disease state at transplantation, host age and CMV seropositivity. Higher CD3, CD4 and CD8 counts were associated with a better overall survival and a lower NRM. Strikingly, when tested in multivariable analysis, higher CD3 and CD8 counts were still significantly associated with a lower NRM. These results indicate that an accelerated T-cell reconstitution correlates with less transplantation mortality, likely due to the protective role of T cells against viral infections. This observation suggests that CD8+ T-cell counts should be investigated as surrogate biomarkers of outcome in prospective haplo-HSCT trials