Giovanna Piaggio

Direct intrabone transplant of unrelated cord-blood cells in acute leukaemia: a phase I/II study

BACKGROUND Cord-blood transplants are associated with delayed or failed engraftment in about 20% of adult patients. The aim of this phase I/II study was to establish the safety and efficacy of a new administration route (intrabone) for cord-blood cells, measured by the donor-derived neutrophil and platelet engraftment. METHODS Adult patients with acute leukaemia, for whom an unrelated stem-cell transplantation was indicated and no suitable unrelated human leucocyte antigen (HLA)-matched donor had been identified, were included in the study and underwent a cord-blood transplant in San Martino Hospital, Genoa, Italy. Eight patients were in first complete remission, ten in second complete remission, and 14 had advanced-stage, refractory disease. HLA matching was 5/6, 4/6, and 3/6 for 9, 22, and one patient, respectively. Cord-blood cells were concentrated in four 5-mL syringes, and were infused in the superior-posterior iliac crest under rapid general anaesthesia. Median transplanted cell dose was 2.6 x 10(7)/kg (range 1.4-4.2). The primary endpoint was the probability of neutrophil and platelet recovery after intrabone cord-blood transplantantion. Secondary endpoints included the incidence of acute graft-versus-host disease, relapse, and overall survival. This trial is registered on the ClinicalTrials.gov website, number NCT 00696046. FINDINGS Between March 31, 2006, and Jan 25, 2008, 32 consecutive patients with acute myeloid leukaemia (n=20) or acute lymphoblastic leukaemia (n=12) underwent a cord-blood transplant (median age 36 years [range 18-66]). No complications occurred during or after the intrabone infusion of cells. Four patients with advanced-stage disease died within 12 days of the procedure. Median time to recovery of neutrophils in 28 patients (>/=0.5 x 10(9)/L) was 23 days (range 14-44) and median time to recovery of platelets in 27 patients (>/=20 x 10(9)/L) was 36 days (range 16-64). All patients were fully chimeric from 30 days after transplantation to the last follow-up visit, suggesting an early complete donor engraftment. No patient developed grade III-IV acute graft-versus-host disease. Causes of death were transplant related (n=5), infection (n=7), and relapse (n=4). 16 patients were alive and in haematological remission at a median follow-up of 13 months (range 3-23). INTERPRETATION Our preliminary data suggest that direct intrabone cord-blood transplantation overcomes the problem of graft failure even when low numbers of HLA-mismatched cord-blood cells are transplanted, thus leading to the possibility of use of this technique in a large number of adult patients.

AKT/NF‐κB inhibitor xanthohumol targets cell growth and angiogenesis in hematologic malignancies

Leukemias are dependent on Akt/NF‐κB activation and angiogenesis.

Endothelial colony-forming cells from patients with chronic myeloproliferative disorders lack the disease-specific molecular clonality marker

Two putative types of circulating endothelial progenitor cells have been recently identified in vitro: (1) endothelial colony-forming cell (ECFC) and (2) colony-forming unit-endothelial cell (CFU-EC). Only the former is now recognized to belong to endothelial lineage. We have used the ECFC and CFU-EC assays to readdress the issue of the clonal relation between endothelial progenitor cells and hematopoietic stem cells in patients with Philadelphia-positive and Philadelphia-negative chronic myeloproliferative disorders. Both ECFCs and CFU-ECs were cultured from peripheral blood mononuclear cells, and either BCR-ABL rearrangement or JAK2-V617F mutation were assessed in both types of endothelial colonies. We found that ECFCs lack the disease-specific markers, which are otherwise present in CFU-ECs, thus reinforcing the concept that the latter belongs to the hematopoietic lineage, and showing that in chronic myeloproliferative disorders the cell that gives rise to circulating ECFC has a distinct origin from the cell of the hematopoietic malignant clone.

The retroviral transduction of HOXC4 into human CD34+ cells induces an in vitro expansion of clonogenic and early progenitors

OBJECTIVE +HOX genes are expressed in the hematopoietic system and increasing data point to their involvement in the control of proliferation and/or differentiation. Genes belonging to the C cluster are preferentially expressed in developing and differentiated lymphoid lineages. However, recent studies demonstrated, by RT-PCR, that the HOXC4 gene is also actively transcribed in the most undifferentiated hematopoietic cells (CD34(+)38(low)) and in more mature myeloid and erythroid progenitors. We evaluated the expression of HOXC4 protein on human CD34(+) cells and the in vitro effect of its overexpression on proliferation and differentiation. MATERIALS AND METHODS We assessed the expression of HOXC4 on human CD34(+) cells using a polyclonal antibody raised against the C-terminal portion of the protein expressed using the baculovirus system. Overexpression of HOXC4 in human CD34(+) cells was obtained by retroviral gene transfer; its effect on clonogenic (CFU-GM, BFU-E, and CFU-GEMM) and early progenitors (LTC-IC) was evaluated. RESULTS The HOXC4 protein is indeed expressed in human CD34(+) cells, and its overexpression in human CD34(+) cells increases the proliferation potential of clonogenic and early progenitors. CFU-GM showed a median threefold expansion (range: 1.1-19.4; p < 0.002) compared with control transduced with the vector alone. The increment of BFU-E was higher (median ninefold, range 2.5-35; p < 0. 0009) and erythroid colonies presented a larger size with normal morphology. An even more marked effect was observed on LTC-IC (median 13, onefold; range 4.1-102.1, p < 0.0001). CONCLUSION We demonstrate that HOXC4 is expressed in CD34(+) cells and that its overexpression induces an in vitro expansion of committed as well as very early hematopoietic progenitors. The most striking effect was obtained on LTC-IC with an expansion of 13.1-fold. The enforced expression of HOXC4 induced a significant increase (p < 0.009) in the number of erythroid colonies compared with CFU-GM, although without perturbing, at least in vitro, the maturation program of the cells. On the other hand, the effect of the gene overexpression did not induce any skewing in the colony types derived from the myeloid lineage.

Deficient reconstitution of early progenitors after allogeneic bone marrow transplantation

Allogeneic bone marrow transplant recipients maintain normal peripheral blood counts long term, suggesting durable support from engrafted stem cells. In order to investigate late hemopoietic reconstitution at the level of committed and early progenitors (LTC-IC), we studied 64 long-term survivors at a median interval of 6 years (range: 2–20) after allogeneic bone marrow transplant. CFU-GM and BFU-E numbers did not differ from normal controls; CFU-GEMM were found to be significantly decreased (1.2 ± 0.2/105vs 3.1 ± 0.4, P = 0.001). The most remarkable defect was however, the low frequency of LTC-IC (3.2 ± 0.6/106vs 54.2 ± 9.3, P = 0.0001) that did not improve with time and did not correlate with phase of the disease, conditioning regimen, CMV infections or GVHD. Number of infused cells and CFU-GM content of marrow grafts did not seem to influence the number of LTC-IC. This study documents a significantly reduced number of early progenitors in BMT patients despite normal numbers of committed progenitors and normal peripheral blood counts. This finding may suggest a permanent reduction of the stem cell reservoir after allogeneic bone marrow transplantation.

Allogeneic bone marrow transplantation (BMT) for refractory Behçet's disease with severe CNS involvement.

Allogeneic bone marrow transplantation (BMT) for refractory Behcets disease with severe CNS involvement

Transplantation of HLA-mismatched CD34+ selected cells in patients with advanced malignancies: severe immunodeficiency and related complications.

This trial was designed to test the use of CD34+ selected haemopoietic stem cells (HSC) in HLA‐mismatched donor–recipient pairs, following intensive conditioning with thiotepa, antilymphocyte globulin (ALG), cyclophosphamide and single‐dose total‐body irradiation (sTBI). 10 patients aged 16–50 with advanced malignancies and a two‐ or three‐antigen mismatched family donor entered this study. Donor marrow and G‐CSF primed peripheral blood cells were processed separately on CD34 columns (Ceprate). The median number of infused CD34+ cells were 5.66 × 106/kg, with 0.55 × 106/kg CD3+ cells. Nine patients received cyclosporin for graft‐versus‐host disease (GvHD) prophylaxis. Median neutrophil counts on day 21 were 2 × 109/l with a median platelet count of 60 × 109/l, but CD4 counts remained extremely depressed throughout the study. Acute GvHD was scored as grade 0–I in two patients, as grade II in seven, and grade III in one. Eight patients died at a median interval of 72 d from HSCT (range 20–144) due to cytomegalovirus (CMV) associated interstitial pneumonitis (IP) (n = 5), renal failure (n = 1), GvHD (n = 1) and Aspergillus meningitis (n = 1). Two patients are alive 365–495 d post transplant, one in remission and one in relapse.

Bone marrow transplantation for chronic granulocytic leukemia

Thirty patients with chronic granulocytic leukemia (CGL), were given cyclophosphamde 60 mg/kg on each of 2 consecutive days, followed by total body irradiation (TBI) 10 Gy and an HLA‐identical bone marrow transplant (BMT). Eleven patients were in the accelerated phase of their disease (CGLacc) or in second/secondary chronic phase (CGL‐2CP), with a median age of 33 years: four patients died of transplant related complications, and four of recurrent leukemia; three patients are alive and well 19, 31, 33 months from BMT. The actuarial 33‐month survival is 27%. The actuarial relapse rate is 50%. Nineteen patients were in their first chronic phase (1CP), with a median age of 32 years: three died of graft versus host disease (GvHD), two of infection, and two of acute respiratory distress syndrome (ARDS); 12 are alive and well 6 to 29 months post‐BMT. The actuarial 29‐month survival is 63%. The actuarial survival of patients younger than 30 years is 63%, compared to 62% for patients older than 30 (P = 0.1). The survival of patients grafted within or after 24 months from the onset of CGL is respectively 87% and 45% (P = 0.04). None of the patients grafted in 1CP had a true hematologic‐cytogenetic relapse. The Ph′ chromosome was detected on one occasion in two patients 12, 13 months post‐BMT: they both remain hematologically normal and Ph1‐negative 3 to 6 months later, after discontinuation of cyclosporin A. This study confirms that survival exceeding 60% can be obtained in CGL in the first chronic phase, whereas less than 30% of patients will survive if grafted in accelerated, second/secondary chronic phase, mainly because of leukemic relapse. The duration of the disease seems to be relevant to the outcome of the transplant. The effect of post‐transplant immunosuppression, in our case cyclosporin A, on the interaction between normal and Ph1‐positive hemopoietic cells, may deserve further attention.

Generation of CFU-c suppressor T cells in vitro. V. A multistep process

Summary. Different cell fractions obtained from five patients with immune severe aplastic anaemia (SAA) in complete autologous haematologic reconstitution were tested for CFU‐c suppression. Bone marrow mononuclear cells (BMMC), but not peripheral blood mononuclear cells (PBMC), showed definite CFU‐c inhibitory activity. On the contrary, both peripheral blood and marrow E rosetting cells (E+) suppressed CFU‐c growth. The suppressor activity of PBE+ cells could not be rescued by adding back PBE‐ cells and/or PB adherent cells (AC). In addition, unfractionated PBMC exposed to sheep red blood cells (SRBC) suppressed CFU‐c growth. PBMC from normal donors exposed to SRBC had no suppressor activity.

Quantitative competitive reverse transcriptase-polymerase chain reaction for BCR-ABL on Philadelphia-negative leukaphereses allows the selection of low-contaminated peripheral blood progenitor cells for autografting in chronic myelogenous leukemia

The Philadelphia (Ph) translocation t(9;22) results in the creation of the BCR-ABL gene, which is now regarded as central to the mechanism that underlies the chronic phase of chronic myelogenous leukemia (CML). From a clinical point of view, BCR-ABL mRNA detection has become the basis for the study of minimal residual disease in CML, particularly when a complete cytogenetic remission is achieved after interferon-alpha (IFN-α) therapy or allogeneic stem cell transplantation. We have recently demonstrated that it is possible to mobilize normal peripheral blood progenitor cells (PBPC) in higher rates if this procedure is performed during the early chronic phase. In an attempt to monitor the leukemic cell content of PBPC collections, we used quantitative-competitive RT-PCR (QC-RT-PCR). Thirty consecutive Philadelphia (Ph) chromosome positive patients were enrolled in this study. After chemotherapy and G-CSF, 14 patients achieved 100% Ph-negative metaphases, nine patients had 34% and seven patients >34% leukemic metaphases. A total of 116 collection samples were studied. For each sample, BCR-ABL transcript numbers and BCR-ABL/ABL ratio were evaluated. A highly significant correlation between Ph-positive metaphases and BCR-ABL transcript numbers (r = 0.84, P< 0.0001) or bcr-abl/abl ratio (r = 0.86, P < 0.0001) was found. for patients that underwent the procedure in early chronic phase, ph-negative collections showed different levels of bcr-abl expression. bcr-abl transcript numbers varied from a median of 100/μg rna in the first and second leukaphereses, to 500/μg rna in the third and fourth leukaphereses, and 1500/μg rna in the fifth leukapheresis (P = 0.002). BCR-ABL/ABL ratio values showed similar kinetics. We have also demonstrated that there is a correlation between low values in BCR-ABL/ABL ratio (≤0.01) in the reinfused PBPC and the achievement of cytogenetic remission after autografting (χ2 test, P = 0.01). In conclusion, this study demonstrates that QC-RT-PCR for BCR-ABL is a reliable and helpful method for monitoring residual leukemic load in mobilized PBPC, particularly in Ph-negative collections. Moreover, QC-RT-PCR allows selection of the best available collections for reinfusion into patients after myeloablative therapy.