Luis Madero

KIR-ligand incompatibility in the graft-versus-host direction improves outcomes after umbilical cord blood transplantation for acute leukemia.

Donor killer cell immunoglobulin-like receptor (KIR)-ligand incompatibility is associated with decreased relapse incidence (RI) and improved leukemia-free survival (LFS) after haploidentical and HLA-mismatched unrelated hematopoietic stem cell transplantation. We assessed outcomes of 218 patients with acute myeloid leukemia (AML n=94) or acute lymphoblastic leukemia (n=124) in complete remission (CR) who had received a single-unit unrelated cord blood transplant (UCBT) from a KIR-ligand-compatible or -incompatible donor. Grafts were HLA-A, -B or -DRB1 matched (n=21) or mismatched (n=197). Patients and donors were categorized according to their degree of KIR-ligand compatibility in the graft-versus-host direction by determining whether or not they expressed HLA-C group 1 or 2, HLA-Bw4 or HLA-A3/-A11. Both HLA-C/-B KIR-ligand- and HLA-A-A3/-A11 KIR-ligand-incompatible UCBT showed a trend to improved LFS (P=0.09 and P=0.13, respectively). Sixty-nine donor–patient pairs were HLA-A, -B or -C KIR-ligand incompatible and 149 compatible. KIR-ligand-incompatible UCBT showed improved LFS (hazards ratio=2.05, P=0.0016) and overall survival (OS) (hazards ratio=2.0, P=0.004) and decreased RI (hazards ratio=0.53, P=0.05). These results were more evident for AML transplant recipients (2-year LFS and RI with or without KIR-ligand incompatibility 73 versus 38% (P=0.012), and 5 versus 36% (P=0.005), respectively). UCBT for acute leukemia in CR from KIR-ligand-incompatible donors is associated with decreased RI and improved LFS and OS.

Clinical value of immunological monitoring of minimal residual disease in acute lymphoblastic leukaemia after allogeneic transplantation

Summary. In this study, we used multiparameter flow cytometry to quantify minimal residual disease (MRD) in 165 serial bone marrow samples from 40 patients diagnosed with acute lymphoblastic leukaemia (ALL) who underwent allogeneic stem cell transplantation (allo‐SCT) from siblings (n = 34) or unrelated donors (n = 6). Samples were prospectively taken from 24 patients before starting the conditioning regimen, at days +30, +60 and +90 and subsequently every 2–3 months. Samples from 16 patients in complete remission (CR) after allo‐SCT were taken at least twice. Six of 24 patients harboured MRD (0·2–10% of mononuclear cells) at transplant and 18 were negative. Estimated disease‐free survival for the MRD+ and MRD– groups at transplant was 33·3% and 73·5% respectively (P = 0·03). During follow‐up, increasing MRD levels were detected in nine patients, a finding that preceded marrow relapse by 1–6 months. Two patients with stable low MRD levels remained in CR. When we used flow cytometry to test the effect of donor leucocyte infusions (DLI) in six patients, we observed that the only sustained remission was achieved when DLI was applied prior to overt relapse. We conclude that MRD by flow cytometry can rapidly assess tumoral burden before transplant to predict outcome, and can be clinically useful for the timing of DLI for increasing levels of leukaemia after transplant.

High-dose chemotherapy with autologous stem cell rescue for children with high risk and recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors

Current treatment for high risk and recurrent medulloblastoma (MB) and supratentorial primitive neuroectodermal tumors (stPNET) has a very poor prognosis in children. High dose chemotherapy (HDCT) and autologous stem cell rescue have improved survival rates. We present 19 patients (thirteen classified in the high risk group and six patients with recurrent disease) that received HDCT and autologous stem cell rescue.In the high risk group [Med Pediatr Oncol 38 (2002) 83], all patients underwent neurosurgical debulking. Standard chemotherapy was prescribed in 10 patients. Radiotherapy was given to 4 patients (all older than 4 years old). In the recurrence disease group [Childs Nerv Syst 15 (1999) 498], five patients underwent surgery. Radiotherapy was given to those who were not previously irradiated. The HDCT in twelve patients consisted of busulfan 4 mg/kg/day, orally over 4 days in 6-hourly divided doses and melphalan at a dose of 140 mg/m2/day by intravenous infusion over 5 min on day −1. Three patients additionally received thiotepa 250 mg/m2/day intravenously over 2 days and four patients additionally received topotecan 2 mg/m2/day over 5 days by intravenous infusion over 30 min. The other seven patients received busulfan and thiotepa at the same doses.Patient’s stem cells were mobilized with granulocyte colony-stimulating factor at a dose of 12 μg/kg twice daily subcutaneously for four consecutive days. Cryopreserved peripheral blood progenitor cells were re-infused 48 h after completion of chemotherapy. With a median follow-up of 34 months (range 5–93) eight complete responses and one partial response were observed. Three patients died of treatment-related toxicities (15%). The 2 year event-free survival was 37.67 ± 14% in all patients and 57 ± 15% for the high risk group.Therefore we conclude that HDCT may improve survival rates in patients with high risk/recurrent MB and stPNET despite treatment toxicity.

Exercise during Hematopoietic Stem Cell Transplant Hospitalization in Children

PURPOSE The purpose of this controlled trial was to assess the effect of an approximately 3-wk intrahospital exercise intervention performed during inpatient hospitalization for pediatric allogeneic hematopoietic stem cell transplant (HSCT) on (i) immune cell recovery and (ii) body composition. METHODS Immune (i.e., blood counts of leukocytes, monocytes, lymphocytes, and lymphocyte subpopulations) and anthropometric variables (i.e., body mass, body mass index, and estimated fat-free mass) were measured before and after (+15 and 30 d) HSCT. Seven children (5 boys and 2 girls; age (mean +/- SD) = 8 +/- 4 yr) with high-risk cancer performed an individualized training program (aerobic + resistance exercises) in their isolated hospital rooms. We also assessed a control group (n = 13; 9 boys and 4 girls; age = 7 +/- 3 yr) with similar medical conditions and following the same transplant protocol. RESULTS In both groups, the dendritic cell count decreased from pre-HSCT to +15 d post-HSCT and thereafter (up to +30 d) remained stabile; however, the posttransplant decrease was more abrupt in the control group than that in the intervention group (-87% vs -63%, respectively, from pre-HSCT to +15 d). The rest of the immune cell parameters measured showed a similar response from pre-HSCT to post-HSCT in both groups. We found a significant effect of the interaction group x time for all anthropometric variables (weight, body mass index, body fat, and fat-free mass), indicating an increase over the hospitalization period only in the intervention group, for example, body mass increased from 32.9 +/- 18.7 kg pre-HSCT to 35.4 +/- 18.6 kg at +30 d in the intervention group versus a decrease from 30.2 +/- 16.6 to 29.3 +/- 6.3 kg in the control group. CONCLUSION Our findings support the feasibility of exercise training interventions during hospitalization, including immunocompromised children.

High-dose busulfan/melphalan as conditioning for autologous PBPC transplantation in pediatric patients with solid tumors

We conducted a prospective pilot study to assess the feasibility and safety of high-dose busulfan/melphalan as conditioning therapy prior to autologous PBPC transplantation in pediatric patients with high-risk solid tumors. From January 1995 to January 1999, 30 patients aged 2–21 years (median 8) were entered into the study. There were 14 females and 16 males. Diagnoses included neuroblastoma in 10 patients; Ewing’s sarcoma and peripheral neuroectodermal tumor (PNET) in 15 patients and rhabdomyosarcoma in five patients. Treatment consisted of busulfan 16 mg/kg, orally over 4 days (from days −5 to −2) in 6 hourly divided doses, and melphalan at a dose of 140 mg/m2 given by intravenous infusion over 5 min on day −1. G-CSF mobilized PBPC were used as autologous stem-cell rescue. One patient developed a single generalized convulsion during busulfan therapy. The most relevant non-hematologic toxicity was gastrointestinal, manifesting as grade 2–3 mucositis and diarrhea in 12 patients. Two patients died of procedure-related complications, one from veno-occlusive disease of liver and multiorgan failure and the other from adult respiratory distress syndrome. Probability of treatment-related mortality was 6.6 ± 4.5%. With a median follow-up of 18 months (range, 1–48), 19 patients are alive and disease-free, the actuarial EFS at 4 years being 55 ± 12% for the whole group. We conclude that high-dose busulfan/melphalan for autologous transplantation in children with solid tumors is feasible even in small patients. It is well-tolerated, with an acceptable transplant-related mortality and has proven antitumor activity.

KIR-HLA receptor-ligand mismatch associated with a graft-versus-tumor effect in haploidentical stem cell transplantation for pediatric metastatic solid tumors.

Killer immunoglobulin‐like receptors (KIRs) on natural killer cells (NKs) recognize groups of human leukocyte antigen (HLA) class I alleles. Cells without an inhibitory HLA ligand may trigger NK activation. Reduced risk of relapse has been reported in malignant hematologic diseases after haploidentical transplantation when HLA ligands against the inhibitory KIRs present in the donor were absent in the recipient. We performed haploidentical transplant in three children with refractory solid tumors. Our results showed that beneficial antitumor effects could be observed in the presence of inhibitory KIR–HLA mismatch. These preliminary results suggest a possible association between disease control and NK cell alloreactivity. Pediatr Blood Cancer 2009;53:120–124.

Collection and transplantation of peripheral blood progenitor cells mobilized by G-CSF alone in children with malignancies

Results of collection and transplantation of peripheral blood progenitor cells (PBPC) mobilized by G‐CSF in 31 children with different malignancies were analysed. A total of 43 aphereses were performed, following administration of granulocyte colony‐stimulating factor (G‐CSF), using a continuous flow blood cell separator (Cobe Spectra) through a central venous catheter. For patients weighing ≤25 kg the extracorporeal line was primed with red blood cells. The mean blood flow rate was 33.2ml/min (range 12–56ml/min). The mean number of mononuclear cells (MNC), granulocyte‐macrophage colony‐forming units (CFU‐GM) and CD34+ cells collected were 7.22×108/kg body weight (b.w.), 15.9×104/kg and 5.44×106/kg respectively.

Increasing incidence of invasive aspergillosis in pediatric hematology oncology patients over the last decade: a retrospective single centre study.

There is scanty information about invasive aspergillosis (IA) in the pediatric population. A review of IA at Hospital Infantil Universitario Niño Jesús between 1996 and 2006 was undertaken to analyze incidence, risk factors, and treatment response. Twenty patients were diagnosed with probable or proven IA during the study period, with a cumulative incidence of 1.96%. Incidence was higher in hematopoietic stem cell transplantation (HSCT) recipients: 2.26% (3.5% in allogeneic HSCT and 1.2% in autologous HSCT). A significative increase in IA incidence was observed along the study period (P=0.013), although this increase did not reach signification if only proven cases were compared (P=0.058). Most patients presented multiple risk factors for IA (87% more than 1, and 47% more than 3). The most frequently described risk factor was chemotherapy (90%), after by long-term neutropenia (90%), and corticotherapy (75%). Main locations of the infection were pulmonary (8 patients), cutaneous (3 patients) and intestinal (3 patients). Six patients presented disseminated IA. Initial response to treatment was 55%, although 3 of these cases had a subsequent episode. Global antifungal response, at the end of the follow-up, was 45%. IA-related mortality was 55%. Global mortality was 90%. Only 2 patients (isolated cutaneous IA cases) survived. Seven patients died due to their underlying malignant disease without active fungal disease. Incidence of IA in oncology children is increasing, and in adults. In our experience, IA is a marker of poor outcome even for patients who initially respond to antifungal treatment.

Lentiviral-mediated Genetic Correction of Hematopoietic and Mesenchymal Progenitor Cells From Fanconi Anemia Patients

Previous clinical trials based on the genetic correction of purified CD34(+) cells with gamma-retroviral vectors have demonstrated clinical efficacy in different monogenic diseases, including X-linked severe combined immunodeficiency, adenosine deaminase deficient severe combined immunodeficiency and chronic granulomatous disease. Similar protocols, however, failed to engraft Fanconi anemia (FA) patients with genetically corrected cells. In this study, we first aimed to correlate the hematological status of 27 FA patients with CD34(+) cell values determined in their bone marrow (BM). Strikingly, no correlation between these parameters was observed, although good correlations were obtained when numbers of colony-forming cells (CFCs) were considered. Based on these results, and because purified FA CD34(+) cells might have suboptimal repopulating properties, we investigated the possibility of genetically correcting unselected BM samples from FA patients. Our data show that the lentiviral transduction of unselected FA BM cells mediates an efficient phenotypic correction of hematopoietic progenitor cells and also of CD34(-) mesenchymal stromal cells (MSCs), with a reported role in hematopoietic engraftment. Our results suggest that gene therapy protocols appropriate for the treatment of different monogenic diseases may not be adequate for stem cell diseases like FA. We propose a new approach for the gene therapy of FA based on the rapid transduction of unselected hematopoietic grafts with lentiviral vectors (LVs).Previous clinical trials based on the genetic correction of purified CD34+ cells with γ-retroviral vectors have demonstrated clinical efficacy in different monogenic diseases, including X-linked severe combined immunodeficiency, adenosine deaminase deficient severe combined immunodeficiency and chronic granulomatous disease. Similar protocols, however, failed to engraft Fanconi anemia (FA) patients with genetically corrected cells. In this study, we first aimed to correlate the hematological status of 27 FA patients with CD34+ cell values determined in their bone marrow (BM). Strikingly, no correlation between these parameters was observed, although good correlations were obtained when numbers of colony-forming cells (CFCs) were considered. Based on these results, and because purified FA CD34+ cells might have suboptimal repopulating properties, we investigated the possibility of genetically correcting unselected BM samples from FA patients. Our data show that the lentiviral transduction of unselected FA BM cells mediates an efficient phenotypic correction of hematopoietic progenitor cells and also of CD34- mesenchymal stromal cells (MSCs), with a reported role in hematopoietic engraftment. Our results suggest that gene therapy protocols appropriate for the treatment of different monogenic diseases may not be adequate for stem cell diseases like FA. We propose a new approach for the gene therapy of FA based on the rapid transduction of unselected hematopoietic grafts with lentiviral vectors (LVs).

Tumor cells as cellular vehicles to deliver gene therapies to metastatic tumors

A long-pursued goal in cancer treatment is to deliver a therapy specifically to metastases. As a result of the disseminated nature of the metastatic disease, carrying the therapeutic agent to the sites of tumor growth represents a major step for success. We hypothesized that tumor cells injected intravenously (i.v.) into an animal with metastases would respond to many of the factors driving the metastatic process, and would target metastases. Using a model of spontaneous metastases, we report here that i.v. injected tumor cells localized on metastatic lesions. Based on this fact, we used genetically transduced tumor cells for tumor targeting of anticancer agents such as a suicide gene or an oncolytic virus, with evident antitumoral effect and negligible systemic toxicity. Therefore, autologous tumor cells may be used as cellular vehicles for systemic delivery of anticancer therapies to metastatic tumors.