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J Reiffers

Publications and source records attributed to J Reiffers.

At least 91 records · Page 5Linked to original sources

Rapid analysis and efficient selection of human transduced primitive hematopoietic cells using the humanized S65T green fluorescent protein.

We have developed an efficient and rapid method to analyze transduction in human hematopoietic cells and to select them. We constructed two retroviral vectors using the recombinant humanized S65T green fluorescent protein (rHGFP) gene. Transduced cells appeared with specific green fluorescence on microscopy or fluorescence-activated cell sorting (FACS) analysis. The rHGFP gene was placed under the control of two different retroviral promotors (LTR) in the LGSN vector and in the SF-GFP vector. Amphotropic retroviruses were tested on NIH/3T3 fibroblasts or human hematopoietic (K562, TF-1) cell lines. Then CD34+ cells isolated from cord blood were infected three times after a 48-h prestimulation with IL-3, IL-6, SCF or with IL-3, IL-6, SCF, GM-CSF, Flt3-L and TPO. After 6 days of expansion, a similar number of total CD34(+)-derived cells, CD34+ cells and CFC was obtained in non-transduced and transduced cells, demonstrating the absence of toxicity of the GFP. A transduction up to 46% in total CD34(+)-derived cells and 21% of CD34+ cells was shown by FACS analysis. These results were confirmed by fluorescence of colonies in methyl-cellulose (up to 36% of CFU-GM and up to 25% of BFU-E). The FACS sorting of GFP cells led to 83-100% of GFP-positive colonies after 2 weeks of methyl-cellulose culture. Moreover, a mean gene transfer efficiency of 8% was also demonstrated in longterm culture initiating cells (LTC-IC). This rapid and efficient method represents a substantial improvement to monitor gene transfer and retroviral expression of various vectors in characterized human hematopoietic cells.

Cells, Cultured↗

Endothelial cell support of hematopoiesis is differentially altered by IL-1 and glucocorticoids.

We investigated the ability of endothelial cells (EC) to support hematopoiesis in contact and non-contact cocultures with isolated CD34+ or CD34/CD38low cells. In the absence of exogenous cytokines, umbilical vein EC (HUVEC) efficiently support proliferation of hematopoietic cells and generation of colony-forming cells (CFC). Cytokines (IL-6, LIF, G-CSF, GM-CSF, M-CSF, but not IL-1, IL-3, IL-7) were detected in HUVEC coculture supernatants. Neutralization of these cytokines profoundly inhibited the ability of EC supernatants to support the differentiation of hematopoietic progenitors and led to an accumulation of immature cells. Contact cocultures were significantly more efficient than non-contact cocultures. The expanded cell population essentially belonged to the myeloid and monocytic lineages. Contact cocultures generated cells expressing the CD61 or CD41 antigens. Interleukin-1alpha (IL-1alpha) augmented EC capacity to support hematopoiesis, this property resulting from the upregulation of cytokine expression. Glucocorticoids (GC) reduced this capacity by downregulating the biosynthesis of cytokines by EC and not by a direct effect on the progenitor cells. EC from the bone marrow microvasculature (BMEC) support the proliferation and the differentiation of hematopoietic progenitors. Synergistic increase in progenitor cells expansion and generation of CFC occurred when EC cocultures were added with exogenous cytokines. Supernatants of IL-1alpha-stimulated EC potentiated the effects of an association of IL-1, IL-3, IL-6, LIF, SCF, Flt3-ligand, TPO, G-CSF, GM-CSF, M-CSF and IL-11 on the proliferation of hematopoietic progenitors suggesting that EC may produce other soluble growth factors potentiating the action of the above set of cytokines.

Antigens, CD34↗

Factors affecting both peripheral blood progenitor cell mobilization and hematopoietic recovery following autologous blood progenitor cell transplantation in multiple myeloma patients: a monocentric study.

The aim of the study was to analyze the factors influencing peripheral blood progenitor cell (PBPC) collection after high-dose cyclophosphamide (HDCYC) (7 g/m2) and hematopoietic recovery after autologous transplantation of HDCYC-mobilized PBPC (ABPCT) in 116 patients with aggressive multiple myeloma (MM). Following HDCYC 74 patients received hematopoietic growth factors (HGF), either G-CSF (n = 19) or GM-CSF (n = 55). All the patients were subsequently planned to undergo ABPCT. PBPC collection was possible for 106 patients. The most important prognostic factor for collection of more than 25 x 10(4) CFU-GM cells/kg and 2 x 10(6) CD34+ cells/kg was the use of HGF (P = 0.002 and 0.009, respectively). Previous use of an alkylating agent, response to treatment before HDCYC, and interval between diagnosis and HDCYC were also significant factors (P = 0.004, 0.025 and 0.001, respectively). The number of CFU-GM cells infused was the most important parameter for rapid and complete hematological recovery after ABPCT (P < 0.0001). Thus the use of HGF post-HDCYC is the major factor which, associated with reduced time between diagnosis and HDCYC and the use of an alkylating agent, could increase the numbers of hematopoietic progenitors collected, and subsequently improve hematopoietic recovery following ABPCT in MM patients.

Adult↗

Collection of Ph-negative progenitor cells with granulocyte-colony stimulating factor in patients with chronic myeloid leukaemia who respond to recombinant alpha-interferon.

This study aimed to demonstrate that sufficient Ph-negative blood progenitors could be collected following administration of glycosylated rhG-CSF (lenograstim) to patients with Philadelphia chromosome (Ph)-positive chronic myeloid leukaemia (CML) who responded to recombinant alpha-interferon (alpha-IFN) (Ph-positive marrow metaphases < 35%). 23 patients received lenograstim (150 microg/m2) once daily for a median of 9 d. Peak circulating numbers of white blood cells (36.4 x 10(9)/l), CD34+ cells (24/ microl) and colony-forming unit-granulocyte-macrophage (CFU-GM; 1346.5/ml) occurred at a median of day 8, day 8 and day 7, respectively. Two to six (median three) leukaphereses (LK) were performed from days 5 to 12. The median number of mononuclear cells (MNC), CD34+ cells and CFU-GM collected per patient was 7.35 x 10(8/)kg, 2.72 x 10(6)/kg and 10.23 x 10(4)/kg, respectively. 22/23 patients had LK which contained either 10(4) CFU-GM/kg and/or 10(6) CD34+ cells/kg; 47LK (from 20/22 patients) were evaluable for cytogenetics. The median percentage of Ph-positive cells was 0, and 43/47 LK (91%) contained <35% Ph-positive cells; 25 (53%) were entirely negative. Sixteen of 20 evaluable patients had one or more LK with <35% Ph-positive cells, and 12 had at least one 100% Ph-negative LK. Mobilization and collection of Ph-negative cells were not influenced by the dose or duration of alpha-IFN administration before (or during) lenograstim administration or by the quality of cytogenetic response (complete v major) during lenograstim administration. No significant side-effects were observed. Thus, lenograstim administration can result in satisfactory Ph-negative blood progenitor cell collection. Autologous transplantation of such cells may be used when indicated.

Adjuvants, Immunologic↗

Total body irradiation-high-dose cytosine arabinoside and melphalan followed by allogeneic bone marrow transplantation from HLA-identical siblings in the treatment of children with acute lymphoblastic leukaemia after relapse while receiving chemotherapy: a Société Française de Greffe de Moelle study.

We investigated the use of a new conditioning regimen followed by allogeneic bone marrow transplantation (BMT) for treating children with acute lymphoblastic leukaemia (ALL) after relapse within 6 months of the completion of therapy. One hundred and sixteen children with acute lymphoblastic leukaemia in second or subsequent complete remission (CR) underwent allogeneic bone marrow transplantation from HLA-identical siblings after a preparative regimen comprising total body irradiation (TBI), high-dose cytosine arabinoside and melphalan (TAM regimen). The Kaplan-Meier product-limit estimate (mean +/- SE) of disease-free survival (DFS) at 7 years was 59.5 +/- 9% (95% confidence interval). The estimated chance of relapse was 22.5 +/- 15% with a median follow-up of 88.5 months (range 51-132). 26 patients (22.4%) died with no evidence of recurrent leukaemia, mainly from interstitial pneumonitis, veno-occlusive disease or acute graft-versus-host disease (GVHD). Three factors significantly affected DFS: acute GVHD. site of relapse and, for children in second remission after a marrow relapse, the disease status at the time of transplantation. The DFS were 59.02 +/- 12.6%, 37.5 +/- 19.8% and 774 +/- 15% among patients in CR2 after a marrow relapse, in CR3 or in untreated partial marrow relapse, and in CR2 after an isolated CNS relapse, respectively. The lowest DFS was seen in children with acute GVHD grades 3-4. Two significant factors were associated with relapse: the marrow status at the time of transplantation and chronic GVHD. The relapse rate was lower among children in CR2 or with chronic GVHD. We conclude that transplantation after the TAM regimen is an effective therapy for this population with acceptable toxicity, particularly for children in second remission after a very early marrow relapse, or those with early isolated CNS involvement.

Adolescent↗

A phase II study of interleukin-2 in 49 patients with relapsed or refractory acute leukemia.

In this report we present the results of a multicenter phase II study of high-dose recombinant Interleukin-2 (rIL-2) in patients with refractory or relapsed acute leukemia. Forty-nine patients with acute myeloid leukemia (AML: 30 patients) or acute lymphoblastic leukemia (ALL: 19 patients) were included. Median age was 30 years (range: 4-71). Four patients were treated for primary refractory disease and 45 for relapsed disease (16 patients > 2nd relapse). Twenty-four patients (49%) had previously received bone marrow transplantation (allogeneic: 5, autologous: 19). Patients were scheduled to receive three 5-day cycles of rIL-2 given every other week. rIL-2 was administered as bolus I.V. infusion of 8 x 10(6) UI/m2 every 8 hours during cycle I and every 12 hours during cycles 2 and 3. Patients received a mean of 76% of rIL-2 planned dose. Main toxicity was hematologic (grade IV thrombopenia: 84%). Hemodynamic and metabolic toxicities lead to treatment discontinuation in 10 patients (20%). Strong immune activation was achieved including a significant increase in activated T-cells and Lymphokine-Activating-Killer cell (LAK) activity. Twenty-seven out of 30 AML patients could be evaluated for response: 2(7%) achieved complete remission (CR) which lasted 3 and 4 months. No response was observed in the 18 assessable ALL patients, most of whom (77 %) presented absolute drug resistance. These results show that this high dose rIL-2 regimen induces significant biological effects and provides some anti-leukemic activity in patients with advanced leukemia. Considering the severe toxicity observed and the limited remission rate achieved here, rIL-2 does not appear to be a valuable therapeutic option for such patients. However, the undoubted anti-leukemic activity of this cytokine invites further investigation especially in the minimal residual disease situation.

Adolescent↗

Ex vivo cytokine expansion of peripheral blood Ph-negative cells in chronic myeloid leukaemia.

Hematopoietic progenitors can be expanded ex vivo in the presence of various cytokine combinations. Since normal early progenitor or stem cells persist in the blood and bone marrow of patients with Philadelphia chromosome [Ph]-positive chronic myeloid leukaemia (CML), the selection of normal (Ph-negative) progenitor cells from CML patients would be of considerable clinical value for ex vivo purging and autologous transplantation. To obtain these cells, CD34-positive (progenitor) cells from the peripheral blood (PB) of CML patients were either pretreated or not with 5-fluorouracil (5FU) and then grown in suspension culture for 7 days with a combination of cytokines. We compared different combinations of cytokines containing interleukin-1 alpha (IL1), interleukin-3 (IL3), stem cell factor (SCF), leukemia inhibitor factor (LIF), Flt3-ligand (FLT3L), and thrombopoietin (TPO). 5FU decreased cell proliferation in the liquid culture but concurrently increased the expansion of CFU-GM. While the addition of cytokines such as FLT3L and TPO improved CFU-GM expansion. FISH and RT-PCR analysis showed that this method significantly favored a higher frequency of Ph-negative cells after expansion in liquid culture. Therefore ex vivo expansion of putatively normal hematopoietic progenitor cells from cytapheresis is feasible in CML.

Antigens, CD34↗

Fulminant hepatitis due to herpes simplex virus-type 2 in early phase of bone marrow transplantation.

Hepatitis due to Herpes Simplex Virus (HSV) is a rare and severe infection in patients with impaired immunity, as bone marrow transplanted. The antemortem diagnosis is often difficult to establish because the clinical features are nonspecific. We report an uncommon cause of fulminant hepatic failure in a neutropenic patient, 14 days after bone marrow transplantation. HSV-2 fulminant hepatitis occurred during acyclovir prophylactic treatment. No observation of HSV hepatitis in this context has been reported since prophylaxis is used. Because of the extremely high apparent mortality associated with HSV hepatitis, and the improved survival noted among the non-marrow-transplant recipients and prolonged survival seen in one marrow transplant recipient, it seems reasonable to urge early and aggressively acyclovir therapy. A liver biopsy seems to be indispensable in the case of hepatic failure in post-marrow-transplantation in order to make rapidly a diagnosis.

Adult↗

Severe infection caused by Stomatococcus mucilaginosus in a neutropenic patient: case report and review of the literature.

A 24-year-old female, in neutropenic phase after chemotherapy for acute myelogenous leukemia (on day 15) was admitted in intensive care unit for infectious pneumonia. Two strains of Stomatococcus mucilaginosus were isolated from peripheral blood cultures. No microorganisms were yielded from bronchoalveolar lavage. Patient's condition improved with prompt instigation of effective antibiotic therapy. This was the first case of septicemia and pneumonia, due to Stomatococcus mucilaginosus, in our unit. Only 26 cases occurring in neutropenic patients with underlying hematologic malignancies were reported in the literature and among these, only five cases with pneumonia were described. The complications of this normal inhabitant of the human oral cavity can be serious and fatal: septic shock, meningitis, acute respiratory distress syndrome. This study illustrate the possible virulence of Stomatococcus mucilaginosus in neutropenic patients.

Acute Disease↗

Early infectious complications after bone marrow transplantation requiring medical ICU admission.

The objective of this study was to define the type, the incidence and the outcome of early infectious complications (mean interval between day 1 post-BMT and the onset of fever was 9+/-3 days) occurring in granulocytopenic bone marrow transplant recipients, requiring medical intensive care unit admission. Over a five-years period, forty-one patients with microbiologically confirmed infection were enrolled, with a statistically significant higher frequency of allogeneic marrow transplant recipients (51%, p < 0.02). Infectious pneumonia occurred in 24 patients (59%), septicemia with septic shock in ten patients (24%), catheter-related infection in 5 patients (12%) and meningitis in 2 patients (5%) (p < 0.001). Twenty-six patients died (63%). Among the patients with confirmed infectious pneumonitis, which occurred most frequently in allogeneic marrow recipients (p < 0.02), 16 died (67%). This poor outcome was related to the requirement of mechanical ventilation. Eight patients (80%) with septicemia and septic shock and the two patients with meningitis died. Bacteria (Pseudomonas aeruginosa and Staphylococcal species) were the most common isolated in bronchoalveolar lavage fluid and blood cultures. We found a lower incidence of fungal or viral infections compared to previous studies. Empiric antimicrobial therapy in the cases of patients admitted in ICU may be included antibiotics anti-Pseudomonas and anti-Staphylococcus, as the ecology of hematology unit. The requirement of mechanical ventilation is the main adverse prognostic factor in transplanted patients. At ICU admission, patients with hepatic failure combined with respiratory failure represented a subgroup with a dismal prognosis.

Adult↗

Karyotype in acute myeloblastic leukemia: prognostic significance for bone marrow transplantation in first remission: a European Group for Blood and Marrow Transplantation study. Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).

The presentation cytogenetic result was correlated with outcome for 999 patients with acute myeloblastic leukemia (AML) having bone marrow transplantation (BMT) in first complete remission (CR1). The karyotype at diagnosis was classified according to the modified Chicago classification. Allogeneic BMT (AlloBMT) was performed in 500 patients and autologous BMT (ABMT) in 499 patients. For both groups, an abnormal chromosome (abn) 5 and/or 7 or a hypodiploid karyotype had a poor outcome, whereas t(15;17), pseudodiploidy, hyperdiploidy and diploidy were associated with a standard prognosis. Abn (16) and t(8;21) were also of standard prognosis for ABMT, but favorable for AlloBMT. When comparing AlloBMT and ABMT in patients with favorable or standard cytogenetics, AlloBMT was of benefit for remission duration and leukemia-free survival (LFS). Patients with an unfavorable karyotype had a similar outcome, regardless of type of BMT. By multivariate analysis, cytogenetics at diagnosis had the strongest prognostic value for relapse, LFS, and survival in AlloBMT. In ABMT, cytogenetics influenced relapse and LFS. We concluded that the karyotype at diagnosis had important prognostic implication in AML grafted in CR1.

Adolescent↗

Plasma cytokines in graft vs host disease and complications following bone marrow transplantation.

A cohort of 201 autologous or allogeneic bone marrow transplanted (BMT) patients were included for studying the evolution of circulating tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) by means of repeated plasma determinations. IL-6 levels were high during major transplant-related complications (TRC) or severe graft vs host disease (GVHD). High levels of TNF-alpha seemed to be associated with chronic GVHD but not with acute GVHD or TRC.

Adolescent↗

Study of the apoptosis induced in vitro by antitumoral drugs on leukaemic cells.

A flow cytometric method for simultaneous apoptotic cell detection and cell cycle analysis was applied on the U937 cell line. Four antitumoral drugs currently used in the treatment of acute myeloid leukaemia were studied in vitro: DNR, IDR, MITO and Ara-C. Our results show a dissociation between the cytostatic effect (the block in the cell cycle observed for low drug concentrations) and the cytotoxic effect (the induction of apoptosis induced by higher concentrations) for all the tested molecules. Low concentrations of Ara-C induced a block in the S phase while higher concentrations (>10(-7) M) induced apoptosis at the G1-S boundary. Low concentrations of anthracyclines (<40 nM DNR and <20nM IDR) induced a block in G2 without apoptosis. Apoptosis was induced in G1 and/or early S phases by higher concentrations of anthracyclines. The concentration inducing 50% apoptosis (IC50) was found to be, respectively, 200 and 40 nM for DNR and IDR. Analysis of MITO-treated cells showed a parallel increase in the percentages of S phase and apoptotic cells. However, the bivariate analysis showed that apoptosis did occur in a population with G1 DNA content. For two other drugs (CAM and COLC), apoptosis occurred for the same concentrations and in the same phase as the block (in S and G2M, respectively). The IC50 of MITO was found to be 100 nM. Cotreatment of the cells with colchicin and either Ara-C or IDR showed that the passage through mitosis was not necessary for the completion of apoptosis at the G1-S boundary. Short incubations of U937 cells with high concentrations of anthracyclines were found to be efficient in inducing further apoptosis. We conclude that, for all the assayed molecules, the cytotoxic and/or cytostatic effects of the antitumoral drugs tested greatly depend on the concentrations used and that, depending on their in vivo pharmacokinetics, the induction of apoptosis could be an important mechanism of action for some of these drugs.

Acute Disease↗

Gene transfer of the uroporphyrinogen III synthase cDNA into haematopoietic progenitor cells in view of a future gene therapy in congenital erythropoietic porphyria.

Congenital erythropoietic porphyria (CEP) is an inherited metabolic disorder characterized by an overproduction and accumulation of porphyrins in bone marrow. This autosomal recessive disease results from a deficiency of uroporphyrinogen III synthase (UROIIIS), the fourth enzyme of the haem biosynthetic pathway. It is phenotypically heterogeneous: patients with mild disease have cutaneous involvement, while more severely affected patients are transfusion dependent. The cloning of UROIIIS cDNA and genomic DNA has allowed the molecular characterization of the genetic defect in a number of families. To date, 22 different mutations have been characterized. Allogeneic bone marrow transplantation is the only curative treatment available for the severe, transfusion-dependent, cases. When bone marrow transplantation cannot be performed owing to the absence of a suitable donor, the autografting of genetically modified cells is an appealing alternative. The best approach to somatic gene therapy in this disease involves the use of recombinant retroviral vectors to transduce cells ex vivo, followed by autologous transplantation of the genetically modified cells. We investigated retroviral transfer in deficient human fibroblasts, immortalized lymphoblasts as well as bone marrow cells, and obtained a complete restoration of the enzymatic activity and full metabolic correction. Using K562 cells, an erythroleukaemic cell line, the expression of the transgene remained stable during 3 months and during erythroid differentiation of the cells. Finally, a 1.6- to 1.9-fold increase in enzyme activity compared to the endogenous level was found in normal CD34+ cells, a population of heterogeneous cells known to contain the progenitor/stem cells for long-term expression. The future availability of a mouse model of the disease will permit ex vivo gene therapy experiments on the entire animal.

3T3 Cells↗

Ex vivo expansion of haematopoietic progenitors on an endothelialized hydroxyapatite matrix.

Autologous haematopoietic progenitor cell (HPC) transplantation is increasingly used to restore haematopoiesis after high-dose chemotherapy treatments. The present study was designed to analyse the ability of hydroxyapatite (HAP) seeded with endothelial cells (EC) to support the proliferation and differentiation of CD34+ HPC in static culture conditions. HAP is endothelializable as assessed by scanning electron microscopy and time-course DNA synthesis analysis using tritiated thymidine incorporated in EC isolated from human umbilical vein cord. Short-term coculture experiments in which CD34+ cells isolated from human cord blood were seeded on endothelialized HAP, were performed. Results show that endothelialized HAP is permissive to CD34+ cell expansion with a maximum expansion obtained between days 7 and 14 of coculture in the presence of IL-1 and IL-3 when compared with other experiments omitting either EC or interleukins. From morphological analyses, the expanded cell population mainly belonged to the myelocytic lineage with 33% mature cells (polymorphonuclear neutrophils and monocytes) at day 14 of coculture. The immature HPC could remain trapped within HAP while giving rise to a more mature progeny that exit from HAP microenvironment.

Journal Article↗

Early allogeneic transplantation favorably influences the outcome of adult patients suffering from acute myeloid leukemia. Société Française de Greffe de Moelle (SFGM).

Allogeneic BMT for patients with acute myeloid leukemia (AML) is presently a reference therapy. The indications for this therapy mainly rely upon prognostic factors, and their importance is constantly reassessed. To examine the impact of time from diagnosis to transplant on survival and leukemia-free survival (LFS), we analyzed 109 patients from the database of the SFGM comprising patients who had all received an HLA-identical allogeneic BMT for a diagnosis of AML in first complete remission (CR1) between January 1987 and December 1992. All patients were conditioned with cyclophosphamide (CY) and total body irradiation (TBI) (CYTBI), and methotrexate (MTX) + cyclosporin A (CsA) were used as graft-versus-host disease (GVHD) prophylaxis. Patient characteristics were: age = 33 +/- 9, M/F = 64/45, white blood cell count (WBC) at diagnosis = 27 +/- 42 x 10(9)/l, FAB distribution: M1 and M2 = 55; M3 = 15, M4 and M5 = 33, M0, M6 and M7 = 6. Karyotyping was carried out for 64 patients: 32 had a normal karyotype, 16 had good prognosis abnormalities (t(8;21), t(15;17), inv 16) and 16 patients had other abnormalities. Eleven patients needed two courses of induction to achieve CR. Time between diagnosis and BMT was 120 (64-287) days. Forty-nine patients developed grade > or = 2 acute GVHD (actuarial probability = 46%). With a median follow-up of 50 months (27-100), the 5-year probabilities for transplant-related mortality (TRM), relapse, overall survival and LFS are respectively 25%, 26%, 59% and 55%. A multivariate analysis showed that survival is adversely influenced by three independent factors: time to transplant (> 120 days vs < or = 120 days), acute GVHD (grade 2-4 vs grade 0-1) and age (> 33 vs < or = 33). LFS is only influenced by the first two of these factors. The favorable impact of a shorter time from diagnosis to transplant should lead to performing the transplant as early as possible. Practically speaking, this means that when such therapy is chosen for a patient with CR1 AML, the search for an allogeneic donor should begin immediately and transplant be performed as soon as possible.

Acute Disease↗

European results of matched unrelated donor bone marrow transplantation for chronic myeloid leukemia. Impact of HLA class II matching. Chronic Leukemia Working Party of the European Group for Blood and Marrow Transplantation.

We have retrospectively analyzed the impact of prognostic factors on the outcome of serologically HLA-matched unrelated donor (UD) BMT for CML. For this purpose, we have studied a cohort of 366 patients transplanted in Europe between January 1985 and December 1994. The median age of the 211 males and 155 females was 34 years; 238 patients were transplanted in first chronic phase and 116 in advanced phases. The median interval from diagnosis to BMT was 827 days. GVHD prophylaxis consisted of CsA and MTX in 202 patients or of ex vivo or in vivo T cell depletion (TCD) in 129. Recently, DNA-based methods of HLA-class II typing have been used to improve donor selection. We obtained complete data on 300 donor/recipient (D/R) pairs. Among them, we have identified three groups of patients, according to specific HLA-DRB1 D/R compatibility. Two hundred and ten patients received marrow from donors identical for HLA-DRB1 (group 1). Thirty-one patients received BMT from a donor who was HLA-DRB1 mismatched (group 2) and 59 from a donor in whom specific HLA-DRB1 typing was not performed (group 3). The overall survival was 37 +/- 3% at 2 years and leukemia-free survival (LFS) was 31 +/- 3%. In univariate analysis, five variables had a favorable effect on LFS: transplant in first chronic phase (P = 0.0001), time interval from diagnosis to BMT shorter than the median (P = 0.01), prophylaxis of GVHD without TCD (P + 0.001), acute GVHD < grade III (P = 0.0009) and HLA-DRB1 D/R matching (P = 0.0001). Transplant-related mortality (TRM) was 49 +/- 4% in group 1, 79 +/- 8% in group 2 and 80 +/- 6% in group 3 (P = 0.0001). Multivariate analysis confirmed that HLA-DRB1 matching was the most significant factor influencing survival (P = 0.04), LFS (P = 0.013) and TRM (P = 0.0049). From these results, we have defined a 'good risk' group, ie patients transplanted in first chronic phase, from an HLA-DRB1 matched donor, without TCD as prophylaxis against GVHD. The 2 year LFS, TRM and relapse incidence for this group were 51 +/- 5%, 47 +/- 5% and 2 +/- 2%, respectively. This suggests that the long-term outcome of patients with favorable prognostic features can approach that of patients transplanted from geno-identical siblings. In contrast, the TRM for patients transplanted for advanced disease from non HLA-DRB1-identical donors was 94%. Such a high TRM clearly indicates that UD BMT is not justifiable for these individuals.

Adolescent↗