Summary:In 1989 we carried out a trial comparing allogeneic BMT to chemotherapy (CT) in 76 children with relapsed acute lymphoblastic leukaemia (ALL). Ten years on we have clinically revised outcome to firmly establish the role of each treatment, to analyse the importance of length of first remission and to provide long-term actuarial results for disease-free survival (DFS) and relapse rate in each group. For 21 patients within the transplantation group, probability of DFS and relapse are 42.8 ± 10.8% and 40.2 ± 11.7% (s.e.), respectively. In the chemotherapy group, probability of DFS is 10.0 ± 4.74% (P = 0.001) and probability of relapse 87.5 ± 5.2% (P = 0.0004). These results strongly reflect those at initial analysis, confirming a key role of BMT in the management of ALL in second remission. Moreover, on univariate analysis only two factors influenced DFS: treatment group and length of first complete remission (less or more than 30 months from first CR). Thus, it seems clear that the best therapeutic option in early relapse is BMT, whereas DFS in late relapse is at the limit of significance (P = 0.07), with a higher relapse rate in the CT group. Although encouraging results using intensified rotational combination chemotherapy have been published, prospective randomised studies are needed to assess with certainty the best therapeutic option in these patients. Keywords: BMT vs chemotherapy; childhood ALL; second CR; revisited In 1989, we concluded that allogeneic bone marrow transplantation (BMT) is the best alternative therapy for children with ALL who have relapsed in their marrow. 1 In that report, we prospectively studied 76 such patients, 21 of whom had a genotypically identical HLA donor and underwent allogeneic BMT. The remaining 55 patients who lacked a suitable donor, received conventional chemotherapy (CT). Probability of survival was significantly higher in the BMT group (47.1 ± 11.7% vs 9.2 ± 5.6%, P Ͻ 0.025). Probability of remaining in complete remission in the BMT group was 58.5% vs 10.9% in the chemotherapy group (P Ͻ 0.005).At the time of publication of those findings and as a consequence of the discouraging results initially obtained by some groups with BMT for ALL patients in second CR, 2,3 many controversies arose, such as whether or not these children should undergo allogeneic BMT. [4][5][6][7] In the last 10 years, despite the lack of well-designed randomised studies with large numbers of patients, all results seem to confirm that high-dose chemotherapy and bone marrow transplantation from an histocompatible donor afford a greater chance of leukaemia-free survival than does conventional chemotherapy. However, it has been recently pointed out 8 that indications for BMT in ALL are not fully established, because of publications involving small numbers of patients, difficulties over selection bias since most patients lack a suitable sibling donor, and importantly, that a very long follow-up is needed to assess results of a second course of chemotherapy.On the other hand, it has been stated th...

Summary. The ability of ex-vivo expanded peripheral blood stem cells (PBSC) to engraft non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice has not been evaluated to date. We investigated the maintenance of primitive SCID-repopulating cells (SRC) and long-term culture-initiating cells (LTCIC) in PBSC expanded with early-acting cytokines, thrombopoietin (TPO), stem cell factor (SCF) and FlT3-ligand (FL) with or without interleukin 3 (IL-3) and IL-6 in short-term (6 d) stroma-free serum-free cultures. TPO 1 SCF 1 FL and TPO 1 SCF 1 -FL 1 IL-3 1 IL-6 produced 5´9^1´97 and 18´25^4´49 (mean^SEM)-fold increase of CD34 1 cells respectively. We tracked cellular division with PKH26 and sorted postmitotic CD341 PKH26 low cells to assess their primitive functional properties. After culture with TPO 1 SCF 1 FL, LTCICs among post-mitotic cells increased 12´08^3´4 times, and 4´3^1´6 times when IL-3 1 IL-6 were added. CD341 PKH26 low cells cultured with TPO 1 SCF 1 FL provided human multilineage (CD34, CD33 and CD19) engraftment in NOD/SCID mice, whereas no human cells were detected in mice injected with cells cultured with1 /CD33 -, CD34 1 /DR -and cells in G 0 /G 1 phase were similar among cells cultured with both cytokine combinations, indicating that the deleterious impact of IL-3 1 IL-6 on the ability to engraft is not translated into phenotypic or cycling features. In conclusion, TPO 1 SCF 1 FL-expanded PBSC maintain multilineage engraftment ability in NOD/SCID mice, which is abrogated by the addition of IL-3 1 IL-6.

The positive role of G-CSF in hastening the myeloid recovery of patients undergoing allogeneic bone marrow transplantation (ALLO-BMT) or autologous bone marrow transplantation (ABMT) has recently been established. Considerable knowledge about adequate doses and route of administration has been accumulated in the past few years. Nonetheless, the optimal time to start growth-factor administration remains undetermined. We have performed a stratified study according to the source of hematopoietic progenitors (ALLO-BMT or ABMT), underlying disease and its stage, and acute graft-versus-host disease (GVHD) prophylaxis regimen and randomized patients in two arms: group A, which started G-CSF on day 0 (36 patients), and group B, which started on day +7 post-BMT (39 patients). The same dose (5 micrograms/kg/day) and route of administration were employed in both groups. We found no significant differences in the time to reach an absolute neutrophil count (ANC) of 0.1, 0.5, and 1 x 10(9)/l and 50 x 10(9) platelets/l (medians: 10 and 11, 14.5 and 14, 17 and 16, 23 and 24 days, respectively, in groups A and B). We did not find differences in the days of fever or days on antibiotic treatment with less than 1 x 10(9)/l ANC, rate of bacteriemia, or days of hospitalization in both groups. In contrast, a considerable saving of G-CSF in B group was found (mean days of infusion in group A, 18, versus 11 in group B) (p < 0.0001). This is equivalent to a saving of 1120 $US per patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma concentration of thrombin-antithrombin III complex (TAT), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), PAI-2, D-dimer complex and urokinase-plasminogen activator (u-PA) activity were studied in 30 patients with acute nonlymphoblastic leukemia (ANLL), before and during antileukemic therapy. Fifteen patients showed signs of disseminated intravascular coagulation (DIC), 10 of them classified as M3, 2 as M2 and 3 as M5 subtypes. The initial levels of TAT complex were elevated in all ANLL patients. This increase was more pronounced in patients with DIC (p < 0.05). TAT increased significantly during the treatment period in all cases. u-PA and PAI-1 levels were elevated but there were no statistically significant differences between patients with and without DIC. PAI-2 levels were below the limit of detection in controls and in patients. However, the initially elevated D-dimer complex levels were significantly higher in DIC cases (p < 0.01) and they increased during the treatment period. A significant and positive correlation between D-dimer and TAT complex values was found in DIC patients (r = 0.68, p < 0.001). The high TAT complex and D-dimer levels further increased during chemotherapy treatment strongly suggest a hypercoagulable state with secondary activation of fibrinolysis not severe enough to manifest itself as clinically evident DIC in the majority of cases.

Summary:Interleukin-2 (IL-2) with or without adoptively transferred Previous reports have demonstrated granulocytelymphokine activated killer (LAK) cells has been used in macrophage colony-stimulating factor (GM-CSF)-several trials in an attempt to induce a graft-versus-leukemediated enhancement of lymphokine activated killer mia effect and to reduce the relapse rate after autologous (LAK) cell function. Based on these studies we have bone marrow or peripheral blood stem cell (PBSC) transdeveloped a model of LAK cell generation from perplantation. [1][2][3] The cytolytic ability of LAK cells against ipheral blood stem cells (PBSC) from cancer patients by in vitro incubation with low-dose interleukin-2 (ILseveral hematological and non-hematological malignancies 2) + GM-CSF. PBSC from seven patients were incuhas been demonstrated in vitro, 4,5 and there are some studbated for 48 h at 37؇C in serum-free culture medium ies suggesting an effective antileukemic potential mediated supplemented with IL-2 at increasing concentrations by LAK cells induced in vivo after IL-2 infusion. 3 Unfortu-(10, 100 or 1000 IU/ml) in the presence or absence of nately, IL-2 responsive precursors in vivo are not present 10 IU/ml GM-CSF. LAK activity generated in cultures immediately after transplant when the immunotherapeutic with 10 IU/ml IL-2 + GM-CSF was significantly higher approach could be more effective, 6,7 and it seems that the than that generated by 10 IU/ml IL-2 and did not differ infusion of in vitro activated bone marrow or PBSC in from LAK generation at optimal concentrations of ILaddition to IL-2 therapy could be advantageous. (100 and 1000 IU/ml). PBSC from five additionalRecently, several other cytokines including interleukinpatients were incubated with low-dose IL-2 + GM-CSF 1, 8 interleukin-4, 9 interleukin-7, 10 interleukin-12, 10 gamma after sequential depletion of the CD4 ؉ and CD8 ؉ T interferon 11 and granulocyte-macrophage colony-stimulatcell subsets. LAK activity was significantly reduced by ing factor 12 (GM-CSF) have been shown to be able to depletion of both CD4 ؉ and CD8 ؉ T cells and almost induce LAK activity themselves or in combination with ILcompletely abolished after depletion of both subsets, 2. In particular, GM-CSF administered after autologous suggesting that T cells and not NK cells are the main bone marrow transplantation significantly enhances the LAK precursors in this model. Six patients have LAK cell function in humans, 13 and increases the in vitro received two courses of LAK cells generated in vitro IL-2-induced LAK activity in mice. 12 Although the intrinsic by low-dose IL-2 + GM-CSF on day +1 and +8 after mechanism for this effect is not clear, it seems that T lym-PBSC transplant in combination with GM-CSF and phocytes rather than NK cells are the main precursors of IL-2 administration in vivo. The mean LAK activity in LAK activity in this model. These findings may have peripheral blood of these patients dramatically important clinical implications because recent studies have increased im...