Marc Benbunan

Autologous skeletal myoblast transplantation for severe postinfarction left ventricular dysfunction

OBJECTIVES This phase I trial was designed to assess the feasibility and safety of autologous skeletal myoblast transplantation in patients with severe ischemic cardiomyopathy. BACKGROUND Experimentally, myoblast grafting into postinfarction myocardial scars improves left ventricular function. METHODS Ten patients were included on the basis of the following criteria: 1) severe left ventricular dysfunction (ejection fraction < or = 35%); 2) the presence of a postinfarction akinetic and nonviable scar, as assessed by dobutamine echocardiography and 18-fluorodeoxyglucose positron emission tomography; and 3) an indication of coronary bypass in remote areas. Skeletal myoblasts were grown from a biopsy taken at the thigh. RESULTS An average of 871 x 10(6) cells (86% of myoblasts) were obtained after a mean period of 16 days and implanted uneventfully across the scar at the time of bypass. Except for one patient whose early death was unrelated to the cell transplantation, all patients had an uncomplicated postoperative course. Four patients showed delayed episodes of sustained ventricular tachycardia and were implanted with an internal defibrillator. At an average follow-up of 10.9 months, the mean New York Heart Association functional class improved from 2.7 +/- 0.2 preoperatively to 1.6 +/- 0.1 postoperatively (p < 0.0001), and the ejection fraction increased from 24 +/- 1% to 32 +/- 1% (p < 0.02). A blinded echocardiographic analysis showed that 63% of the cell-implanted scars (14 of 22) demonstrated improved systolic thickening. One noncardiac death occurred 17.5 months after transplantation. CONCLUSIONS These preliminary data suggest the feasibility and safety of autologous skeletal myoblast transplantation in severe ischemic cardiomyopathy, with the caveat of an arrhythmogenic potential. New-onset contraction of akinetic and nonviable segments suggests a functional efficacy that requires confirmation by randomized studies.

Randomized trial and local biological effect of autologous platelets used as adjuvant therapy for chronic venous leg ulcers.

OBJECTIVES Platelet products have been proposed as adjuvant therapy for wound healing. We undertook this study to determine the healing effect of topically applied frozen autologous platelets (FAP) on chronic venous ulcers, compared with effect of placebo, and whether use of topical FAP modifies local expression of vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF), interleukin 8 (IL-8), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in wound fluid. METHODS This randomized, placebo-controlled, double-blind trial was carried out in institutional practice, with ambulatory patients with proved chronic venous leg ulcers. In all patients, whole venous blood was drawn for preparation of FAP. FAP or normal saline solution was applied three times per week for up to 12 weeks, together with hydrocolloids and standardized compression bandages. Leg ulcer surface was assessed with numerical pictures. IL-8, VEGF, KGF, and TIMP-1 levels were determined (enzyme-linked immunosorbent assay) in wound fluid after each 4 weeks of treatment. RESULTS Fifteen patients were randomized into two groups with comparable leg ulcer characteristics. Mean percent reduction in ulcer area was 26.2% in the FAP group versus 15.2% in the placebo group (P =.94). One ulcer in each group was completely healed at study end. Levels of TIMP-1 increased significantly during FAP treatment. IL-8 concentration was significantly lower in wound fluid of healing ulcers than in the fluid of nonhealing ulcers, in both FAP and placebo groups. Growth factor levels were not modified with FAP treatment. CONCLUSION Topical autologous platelets have no significant adjuvant effect on healing of chronic venous leg ulcers and increased wound fluid TIMP-1 concentration. Ulcer healing is associated with a decrease in wound fluid IL-8.

Complete correction of Glanzmann's thrombasthenia by allogeneic bone‐marrow transplantation

Summary Allogeneic bone marrow transplantation (BMT) successfully corrected type I thrombasthenia in a 4‐year‐old boy. The donor was his HLA‐A, B and D identical 14‐year‐old brother who was heterozygous for thrombasthenia. A first transplant after conditioning with cyclophosphamide and thoracoabdominal irradiation was rejected, but a second transplant using CCNU, cyclophosphamide, procarbazine and horse antihuman thymocyte globulin in the preparative regimen was successful. Engraftment was proven by studies of platelet membrane antigens, PLA1 and glycoprotein IIb/IIIa complex and by platelet function studies. Haemor‐rhagic manifestations completely disappeared; platelet membrane markers and clot retraction returned promptly to normal values, and platelet aggregation tests more slowly. Twenty‐four months after bone‐marrow transplant, the patient was well with mild chronic hepatic graft versus host disease. BMT therefore appears to be a possible treatment for severe inherited platelet disorders.

Recovery, viability and clinical toxicity of thawed and washed haematopoietic progenitor cells: analysis of 952 autologous peripheral blood stem cell transplantations.

Cryopreservation and thawing of haematopoietic stem cells are associated with cell loss and infusion-related toxicities. We analysed viability, total nucleated cell (TNC) and CD34+ cell recovery, and infusion-related toxicities of 952 thawed and washed products. Mean TNC and CD34+ viable cells recoveries were 55.9±18.6 and 98.0±36.5%, respectively. Mean cell viability was 68.25±18.9%. TNC recovery was correlated with viability but independent of the initial nucleated cell concentration. No difference in TNC recovery or viability was observed according to underlying diseases, except for myeloma, for which these variables were significantly lower (P<0.05). CD34+ cell recovery was not correlated with viability or CD34+ initial count and was similar for all diseases. Cryostorage duration was not associated with cell loss. Immediate adverse events occurred in 169 patients (19%) and were moderate (grade I or II) for the majority of patients. Clinical toxicity was associated with a higher infused cell number and the presence of clumps in infused bags. The washing procedure of cell products lead to a low rate of adverse events, but patients transplanted with high cell numbers or bags in which clumps were identified are predisposed to such complications.

Association of bone marrow natural killer cell dose with neutrophil recovery and chronic graft-versus-host disease after HLA identical sibling bone marrow transplants

Allogeneic bone marrow (BM) transplant (BMT) outcomes have been correlated with the infused nucleated, CD34+, and T‐ cell dose. The potential impact of natural killer (NK) BM infused cell dose has however not been established. We analysed the outcomes of 78 patients receiving an HLA identical BMT. A higher NK cell dose was associated with the speed of neutrophil (P = 0·05) and platelet recovery (P = 0·04). Higher nucleated cells, CD34+, CD3+, CD3+/4+, CD3+/8+ and NK cell dose were associated with a lower incidence of chronic GvHD (cGvHD) in univariate analysis. In multivariate analysis, the risk of cGvHD was increased by a lower NK cell dose [hazard ratio (HR) = 2·3 (1·2–4·4) for cell dose <0·9 × 106/kg; P = 0·01] and an older age [HR = 1·4 /10 years (1·1–1·8); P = 0·002]. In addition, a higher CD3+/4+ and NK cell dose were associated with a decreased incidence of viral infections (P = 0·03 and P = 0·06 respectively). No specific cell subpopulation infused dose was associated with survival. In conclusion, a higher BM NK cell dose is associated with an increased speed of neutrophil recovery and a decreased incidence of cGvHD.

Hematologic Recovery and Survival of Lymphoma Patients After Autologous Stem-Cell Transplantation: Comparison of Bone Marrow and Peripheral Blood Progenitor Cells

Autologous stem-cell transplantation is widely used as part of the treatment of poor prognosis lymphoma patients. Since 1986, peripheral blood progenitor cells (PBPC) mobilized by chemotherapy and/or hematopoietic growth factors have progressively been used instead of autologous bone marrow (BM) cells. Toxicity, engraftment and long-term outcome were compared in a population of relapsing or refractory lymphoma patients given high-dose therapy. During 1986 to 1993, 150 patients with refractory or relapsed non-Hodgkins lymphomas (n = 93) or Hodgkins disease (n = 57) received intensive therapy followed by the reinjection of BM (n = 72) or PBPC (n = 78). PBPC were collected by aphereses during the phase of hematologic recovery after mobilization by chemotherapy alone (n = 36) or associated with GCSF (n = 43). Conditioning regimens included chemotherapy alone in 77%, associated with total body irradiation (TBI) in 23%. After stem-cell reinfusion, 55% of the PBPC group received GCSF versus 24% in the BM group. Results show that the median time to neutrophil counts > 500/microliters and platelets > 50,000/microliters was significantly shorter in the PBPC than the BM group, respectively 13 versus 23 days and 18 versus 26 days (P < 0.05). This difference remained significant (P < 0.05) when patients were stratified according to the administration or not of GCSF after transplantation. PBPC grafting after high-dose therapy was associated with a median reduction of the hospital stay of 10 days. The majority of patients (90%) maintained normal blood counts at 3 months, and no secondary graft failure was observed in either group. The use of TBI in the conditioning regimen was the only significant factor affecting long-term hematologic recovery. For relapsing patients with histologically aggressive lymphomas, overall survival and failure-free survival were similar in both groups. In conclusion, PBPC transplantation is a safe procedure associated with improvement of hematopoietic recovery and a shortened hospital stay.

ABO-mismatched marrow processing for transplantation: results of 114 procedures and analysis of immediate adverse events and hematopoietic recovery

BACKGROUND:  Red cell (RBC) depletion is needed to bypass ABO mismatch in allogeneic bone marrow transplantation (BMT). Technical and clinical data obtained after bone marrow (BM) processing with a continuous‐flow cell separator (Cobe Spectra, Gambro BCT) are reported.

Bone Marrow Microenvironment in Fanconi Anemia: A Prospective Functional Study in a Cohort of Fanconi Anemia Patients

Fanconi anemia (FA) is a rare condition due to the genetic inactivation of the FA/BRCA pathway. During childhood, most FA patients display progressive bone marrow failure (BMF), the mechanism of which has not been clarified to date. We analyzed BM mesenchymal stem cells (MSCs) from a series of 20 FA patients with BMF (patient median age 12.5 years old, range 7-34). Expression of FANCD2 and sensitivity to mitomycin C, differentiation capacities, and hematopoiesis-supporting abilities, as well as proliferation, cell senescence, and telomere length were assessed. FA MSCs demonstrated hypersensitivity to mitomycin C compared to control MSCs, as expected for FA cells. FA MSCs had normal immunophenotype, support long-term culture of hematopoietic stem cells (HSCs), and display normal differentiation capacities. Telomere loss during cell aging was similar for FA and control MSCs. However, FA MSCs showed reduced long-term proliferation ability, higher stem cell factor and interleukin-6 levels, and increased expression of senescent-associated beta-galactosidase compared to normal MSCs, suggesting a potential role of the BM microenvironment in long-term BMF.

Influence of bone marrow graft B lymphocyte subsets on outcome after HLA‐identical sibling transplants

The potential role of the infused B cell subset after Hematopoietic Stem Cell Transplantation has not been yet studied. The present study analyzed the impact of B cells on transplant outcome in 254 patients who received a bone marrow graft from a human leucocyte antigen‐identical sibling donor. The influence of B lineage‐specific hematopoietic progenitor cells (CD34+ CD19+) and B cells (immature and mature B cells, CD34− CD19+) was also analyzed. All included patients received a myeloablative regimen. The cumulative incidence function of acute graft‐versus‐host (GvHD) grade II to IV was 48% and was inversely associated with the number of CD34+ CD19+. There were no statistically significant associations between B cell subsets and chronic GvHD or survival. The CD34+ CD19+ B cell subset remained significantly associated with acute GvHD in multivariate analysis (Relative risk = 0·32, 95% confidence interval: 0·11–0·92, P = 0·035). In conclusion, a higher B lineage‐specific hematopoietic progenitor cells (CD34+ CD19+) cell dose is associated with a significant decrease incidence of acute GvHD.

Blood stem cell collection using chemotherapy with or without systematic G-CSF: experience in 52 patients with multiple myeloma

Harvesting of peripheral blood stem cells (PBSCs) following chemotherapy and G-CSF administration is currently performed for hematological therapies. However, a procedure based on the use of a large quantity of G-CSF is relatively costly. Therefore, we retrospectively compared the effects of two PBSC mobilization procedures in a population with recently diagnosed multiple myeloma. The first procedure consisted of chemotherapy and systematic G-CSF administration (group 1: 24 patients). The second consisted of chemotherapy alone, G-CSF having been administered only in the case of failure of PBSC mobilization or delayed white blood cell (WBC) recovery (group 2: 28 patients). Leukapheresis was performed when WBC recovery reached 1 × 109/l if the peripheral blood CD34+ cell count was over 10/μl. Leukapheresis was maintained until a total of 2.5 × 106 CD34+ cells/kg was harvested. A significant difference was observed between the two groups only in regard to the median period of WBC recovery (delayed for group 2) and the number of CD34+ cells/kg collected on the first leukapheresis (higher for group 1) but not to the proportion of patients with failure of PBSC collection. Ten group 2 patients, who had insufficient CD34+ cells after WBC recovery or delayed WBC recovery, received G-CSF which resulted in sufficient PBSC harvesting in nine. To obtain a sufficient CD34+ cell level, the patients without systematic G-CSF administration had more leukaphereses (2.1 vs 1.5) but the mean consumption of G-CSF per patient was eight times less than in the other group. Nonsystematic use of G-CSF before WBC recovery or preferentially its introduction just after, could be an interesting economical alternative in PBSC mobilization but should be assessed by a prospective controlled study of cost/efficacy.