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Massimo F Martelli

Publications and source records attributed to Massimo F Martelli.

At least 37 records · Page 2Linked to original sources
PubMed2005

Hematopoietic stem cell transplantation across major genetic barriers: tolerance induction by megadose CD34 cells and other veto cells.

Studies in mice and humans demonstrate that transplantation of hematopoietic progenitors in numbers larger than commonly used overcomes major genetic barriers. In vitro studies suggest that veto cells, within the population of hematopoietic progenitors, facilitate this favorable outcome. Tolerance induction can be further enhanced by other veto cells. Perhaps the most potent veto cell is the CD8(+) CTL. However, this cell is also associated with marked GVHD, which can be separated from the veto activity by generating anti-third party CTLs under IL-2 deprivation.

Animals↗
PubMed2005

Natural killer cell alloreactivity in haploidentical hematopoietic stem cell transplantation.

Natural killer (NK) cells are primed to kill by several activating receptors. NK cell killing of autologous cells is prevented because NK cells coexpress inhibitory receptors (killer cell immunoglobulin-like receptors [KIR]) that recognize groups of (self) major histocompatibility complex class I alleles. Because KIRs are clonally distributed, the NK cell population in any individual are constituted of a repertoire with a variety of class I specificities. NK cells in the repertoire mediate alloreactions when the allogeneic targets do not express the class I alleles that block them. After haploidentical hematopoietic transplantation, NK cell-mediated donor-versus-recipient alloresponses reduce the risk of relapse in acute myeloid leukemia patients while improving engraftment and protecting against graft-versus-host disease. High-resolution molecular HLA typing of recipient and donor, positive identification of donor KIR genes, and, in some cases, functional assessment of donor NK clones identify haploidentical donors who are able to mount donor-versus-recipient NK alloreactions.

Haploidy↗
PubMed2005

The hypereosinophilic syndrome: fluorescence in situ hybridization detects the del(4)(q12)-FIP1L1/PDGFRA but not genomic rearrangements of other tyrosine kinases.

BACKGROUND AND OBJECTIVES: According to WHO criteria, the idiopathic hypereosinophilic syndrome (HES) is defined as persistent eosinophilia (>1.5x10(9)/L) without underlying causes, which is associated with signs or symptoms of organ involvement. Increased bone marrow blasts (>5%) or cytogenetic/genetic markers indicate chronic eosinophilic leukemia (CEL). A cryptic deletion of 4q12, i.e. del(4)(q12), producing the FIP1L1/PDGFRA fusion gene, identifies a distinct CEL subgroup (4q-/CEL). Our aims were: a) to use interphase-fluorescent in situ hybridization (FISH) to detect the cryptic 4q12 deletion; b) to compare the clinico-hematologic features of 4q-/CEL with other HES; c) to investigate whether PDGFRB, FGFR1, ABL1, and ETV6-activated tyrosine kinases are rearranged in CEL/HES. DESIGN AND METHODS: This multicenter study included 20 patients fulfilling the WHO criteria for HES and 6 patients without signs/symptoms of end-organ involvement. Double-color FISH was applied in all cases to investigate del(4)(q12). Further interphase-FISH assessed whether PDGFRB/5q33, FGFR1/8p11, ABL1/9q34, and ETV6/12p13, undergo rearrangements in HES. RESULTS: Ten of the 26 patients (9 males and 1 female) had a cryptic del(4)(q12)-FIP1L1/PDGFRA which was confirmed by reverse transcription polymerase chain reaction (RT-PCR) analysis in four. Hepatomegaly and splenomegaly were significantly more frequent in these 10 than in the other 16 patients. Seven of these 10 patients received imatinib mesylate therapy and all achieved hematologic remission. In 3 of the patients interphase-FISH and RT-PCR demonstrated cytogenetic and molecular remission. Improvements were observed in signs and symptoms of cardiac and central nervous system involvement in 2 and 1 patient, respectively. Rearrangements of PDGFRB, FGFR1, ABL1, or ETV6 were not detected in this study. INTERPRETATION AND CONCLUSIONS: FISH is a reliable diagnostic test for differentiating 4q-/CEL from other forms of HES, allowing an early diagnosis of good responders to imatinib mesylate therapy. For the first time we show that PDGFRB, FGFR1, ABL1 and ETV6 are not rearranged in HES and 4q-/CEL cases we studied.

Adrenal Cortex Hormones↗
PubMed2004

Immune regulatory activity of CD34+ progenitor cells: evidence for a deletion-based mechanism mediated by TNF-alpha.

Previous studies suggest that cells within the CD34(+) hematopoietic stem cell compartment are endowed with immune regulatory activity. Furthermore, it is possible to expand the human regulatory cells upon short-term culture of purified CD34+ cells with an early-acting cytokine cocktail. We now show that addition of anti-CD28, anti-CD2, interleukin-2 (IL-2), anti-IL-10, or IL-12 to the bulk mixed lymphocyte reaction (MLR) cannot reverse the inhibitory activity of the CD34+ cells, ruling out anergy-based mechanisms or mechanisms involving Th1-Th2 skewing. Furthermore, phenotyping of cells present after addition of CD34+ cells to the bulk MLR ruled out potential induction of plasmacytoid dendritic precursors, known to be endowed with regulatory activity. In contrast, the inhibitory activity of CD34+ cells could be reversed by adding the caspase inhibitor BD-FMK to the bulk MLR, indicating a deletion-based mechanism. The deletion can be inhibited by anti-tumor necrosis factor-alpha (anti-TNF-alpha) and not by anti-transforming growth factor-beta (anti-TGF-beta), suggesting a potential role for TNF-alpha in the regulatory activity of CD34+ cells.

Antibodies, Monoclonal↗
PubMed2004

Transplantation of haploidentically mismatched stem cells for the treatment of malignant diseases.

Hematopoietic stem cell transplantation (HSCT) from HLA haploidentical mismatched donors has recently been developed for patients with high-risk acute leukemia who do not have a matched donor. After a high intensity conditioning regimen the HLA barrier is overcome by infusing a graft containing a megadose of T cell-depleted progenitor cells. Nowadays, for graft processing automated peripheral blood CD34(+) cell immunoselection is time and labor saving and ensures a high CD34(+) cell recovery rate. Besides providing 4.5 log T cell depletion of the graft, it guarantees a 3.5 log B cell depletion, which helps prevent EBV-related lymphoproliferative disorders. Excellent engraftment rates are associated with a very low incidence of graft-versus-host disease and regimen-related mortality even in patients who are over 40 years old. Overall, event-free survival and transplant-related mortality compare favorably with reports from unrelated matched transplants. Donor natural killer cell alloreactivity also plays a role in improving outcome in patients with acute myeloid leukemia. These results show the haploidentical transplant to be a viable, alternative source of stem cells for adults with acute leukemia at high-risk of relapse who do not have matched donors, and encourage extending it to patients with an indication to transplant.

Acute Disease↗
PubMed2004

Cryptic insertion producing two NUP98/NSD1 chimeric transcripts in adult refractory anemia with an excess of blasts.

We performed cytogenetic and molecular studies on an adult patient with refractory anemia with an excess of blasts with an add(11)(p15). Multicolor fluorescence in situ hybridization (FISH) identified the extra material on 11p as belonging to chromosome 15. Metaphase FISH with probes for chromosomes 5, 11, and 15 revealed a complex four-break rearrangement. Clone RP5-1173K1, containing exons 10-20 of the NUP98 gene, gave three fluorescence signals on the normal 11, the der(5), and the der(15). 3'-RACE-PCR identified an in-frame fusion between NUP98 and NSD1, which was confirmed by RT-PCR. Two different spliced forms, that is, NUP98 exon 11/NSD1 exon 6 and NUP98 exon 12/NSD1 exon 6, were detected. The reciprocal NSD1/NUP98 was not found. A dual-color experiment with RP5-1173K1 and CTC-549A4, spanning the entire NSD1 gene, indicated an insertion of NUP98 into the NSD1 locus. This is the first report of an adult with myelodysplastic syndrome (MDS) harboring an NUP98/NSD1 fusion resulting from insertion of 5'-NUP98 into the NSD1/5q35 locus.

Amino Acid Sequence↗
PubMed2004

Natural killer cells as a therapeutic tool in mismatched transplantation.

Natural-killer-cell-mediated, donor-vs-recipient alloresponses occur following transplantation of human-leukocyte-antigen (HLA)-haplotype-mismatched haematopoietic stem cells. Natural killer (NK) cell alloreactivity reduces the risk of relapse in acute myeloid leukaemia patients, while improving engraftment and protecting against graft-vs-host disease. NK cells are primed to kill by several activating receptors. NK cell killing of autologous cells is prevented as NK cells co-express inhibitory receptors (killer cell Ig-like receptors, KIR) that recognize groups of (self) major histocompatibility complex class I alleles. As KIRs are distributed clonally, the NK cell population in any individual constitutes a repertoire with different allospecificities. NK cells in the repertoire mediate alloreactions when the allogeneic targets do not express class I alleles that block them. High-resolution molecular HLA typing of recipient and donor, positive identification of donor KIR genes and, in some cases, functional assessment of donor NK clones will identify haplo-identical donors who are able to mount donor-vs-recipient NK alloreactions.

Adoptive Transfer↗
PubMed2004

Melphalan versus melphalan plus busulphan in conditioning to autologous stem cell transplantation for low-risk multiple myeloma.

INTRODUCTION: High-dose chemotherapy conditioning regimens for autologous stem cell transplantation generally give similar results in multiple myeloma. We compared two regimens: melphalan versus melphalan plus busulphan. METHODS: In all, 30 untreated patients with stage III low-risk multiple myeloma were studied. After induction with three VAD courses and mobilization with cyclophosphamide 7 g/m(2) and recombinant human granulocyte-colony stimulating factor (rHuG-CSF) (10 microg/kg b.w./die), they received melphalan 200 mg/m(2) (arm A) or busulphan 16 mg/kg plus melphalan 100 mg/m(2) (arm B) for conditioning for transplantation. All patients received maintenance therapy with Interferon 3 MU x 3/week. RESULTS: Time to engraftment after transplantation was similar in both groups. All patients received rHuG-CSF after reinfusion of peripheral stem cells. No differences emerged in transplant-related infective and noninfective complications. There were no transplant-related deaths. A better response was observed in the melphalan plus busulphan regimen (85 versus 75%, P<0.05). The 5-year overall survival with this regimen was 56 versus 49% with melphalan, and the median survival was 126 months versus 108 months for melphalan (P=0.7). The median progression-free survival was 121 months for melphalan plus busulphan versus 97 months for melphalan (P=0.05). CONCLUSION: These two conditioning regimens showed similar overall response rate and overall survival, though progression-free survival was better with busulphan plus melphalan.

Adult↗
PubMed2003

Different mechanisms lead to a karyotypically identical t(20;21) in myelodysplastic syndrome and in acute myelocytic leukemia.

A new t(20;21)(q11;q11), associated with a deletion on the long arm of chromosome 20, was found in one patient with an acute myelocytic leukemia (AML) and in one with myelodysplastic syndrome (MDS). In both cases deletion was interstitial, extending from band q11 to band q13, as shown by comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). FISH analysis with whole arm paints, subtelomeric probes, and locus-specific probes for the long arms of chromosomes 20 and 21 revealed in patient 1 a reciprocal translocation between the deleted 20q and the long arm of chromosome 21, that is, del(20)(q11q13)t(20;21)(q11;q11), and in patient 2, material from 21q was inserted into the deleted 20q, that is, del(20)(q11q13)ins(20;21)(q11;q11q22). This is the first identification of a complex 20;21 rearrangement in MDS/AML. Deletion at 20q and juxtaposition between 20q11 and 21q11 appear to be the critical genomic events.

Aged↗
PubMed2003

Human homeobox gene HOXC13 is the partner of NUP98 in adult acute myeloid leukemia with t(11;12)(p15;q13).

The chimeric gene NUP98/HOXC13 was detected in a patient with a de novo acute myeloid leukemia and a t(11;12)(p15;q13). Fluorescence in situ hybridization with PAC1173K1 identified the breakpoint on 11p15, indicating that the NUP98 gene was involved in the translocation. At 12q13, the breakpoint fell within BAC 578A18, selected for the homeobox C (HOXC) cluster genes. RACE-PCR showed that HOXC13 was the partner gene of NUP98. To date, HOXC13 is the eighth homeobox gene that, as the result of a reciprocal translocation, fuses with NUP98 in myeloid malignancies.

Fatal Outcome↗
PubMed2003

Typical genomic imbalances in primary MALT lymphoma of the orbit.

Primary orbital non-Hodgkin lymphoma is a mucosa-associated lymphoid tissue (MALT)-type extranodal marginal zone lymphoma. Little information is available on its genome as conventional cytogenetics is limited by scarce biopsy material, while fluorescence in situ hybridization (FISH) explores only selected regions. Comparative genomic hybridization (CGH) performs full genomic analysis and is applicable to different sources of DNA, such as fresh and frozen cells, as well as paraffin-embedded tissues. In this study, CGH was used to analyse primary MALT lymphoma of the orbit. Aneuploidy was identified in six of the ten cases studied. Gains (19) were more frequent than losses (5). The most frequent duplications involved chromosome 3 (common region at 3q24-qter), as expected in marginal zone lymphoma, and chromosome 6 (common region at 6p21.1-21.3), which is typical of an orbital location. Other chromosome gains were found at 1p, 7, 8q, 9q, 12, 13, 17, 18, 19, 22, and X. Losses were located at 1q, 6q, 9q, 11q, and 13q. Two cases showed isolated duplications of chromosome 6p or 9q. Isolated imbalances were found only in tumours affecting the conjunctiva. Complex aneuploidies were observed in lymphoma of the retro-orbital tissue. In summary, CGH in orbital MALT lymphoma provided new insights into typical genomic imbalances and underlying pathogenetic mechanisms.

Aged↗
PubMed2003

Hematopoietic stem cell transplantation across major genetic barriers: tolerance induction by megadose CD34 cells and other veto cells.

Studies in mice and humans demonstrate that transplantation of hematopoietic progenitors in numbers larger than commonly used ("megadose" transplants) overcomes major genetic barriers. In vitro studies suggest that veto cells, within the population of hematopoietic progenitors, facilitate this favorable outcome. Thus, when purified CD34(+) cells were added to bulk mixed-lymphocyte reactions (MLRs) they suppressed CTLs against the donor's stimulators, but not against stimulators from a third party. This tolerizing activity depends on cell contact and can be blocked by the caspase inhibitor BD-FMK, suggesting that the effector host T cells are deleted by apoptosis upon interaction with the CD34(+) cells. Early myeloid CD33(+) cells generated by short-term ex vivo expansion of CD34(+) cells also exhibit veto activity, and these cells can be grown in large numbers. Tolerance induction can be further enhanced by other veto cells. Perhaps the most potent veto cell is the CD8+ CTL. However, this cell is also associated with marked GVHD (graft-versus-host disease. GVHD can be separated from the veto activity by generating anti-third party CTLs under IL2 deprivation. Under such selective pressure only the stimulated clones which make IL2 can survive, while anti-host clones die. In vivo studies show that such anti-third party veto CTLs can be used safely for tolerance induction without GVHD.

Animals↗
PubMed2002

Tolerance induction by megadose hematopoietic progenitor cells: expansion of veto cells by short-term culture of purified human CD34(+) cells.

Stem cell-dose escalation is one way to overcome immune rejection of incompatible stem cells. However, the number of hematopoietic precursors required for overcoming the immune barrier in recipients pretreated with sublethal regimens cannot be attained with the state-of-the-art technology for stem cell mobilization. This issue was addressed by the observation that cells within the human CD34(+) population are endowed with veto activity. In the current study, we demonstrated that it is possible to harvest about 28- to 80-fold more veto cells on culturing of purified CD34(+) cells for 7 to 12 days with an early-acting cytokine mixture including Flt3-ligand, stem cell factor, and thrombopoietin. Analysis of the expanded cells with fluorescence-activated cell-sorter scanning revealed that the predominant phenotype of CD34(+)CD33(-) cells used at the initiation of the culture was replaced at the end of the culture by cells expressing early myeloid phenotypes such as CD34(+)CD33(+) and CD34(-)CD33(+). These maturation events were associated with a significant gain in veto activity as exemplified by the minimal ratio of veto to effector cells at which significant veto activity was detected. Thus, whereas purified unexpanded CD34(+) cells exhibited veto activity at a veto-to-effector cell ratio of 0.5, the expanded cells attained an equivalent activity at a ratio of 0.125. The availability of novel sources of veto cells such as those in this study might contribute to the realization of immunologic tolerance in "minitransplants," without any risk of graft-versus-host disease.

Antigens, CD↗
PubMed2002

NUP98 is fused to the NSD3 gene in acute myeloid leukemia associated with t(8;11)(p11.2;p15).

Fusion between the NUP98 and NSD3 genes in a patient with acute myeloid leukemia associated with t(8;11)(p11.2;p15), is reported for the first time. The t(8;11)(p11.2;p15) was identified by classical cytogenetics. Fluorescence in situ hybridization (FISH) analysis revealed a split signal with a mix of BAC 118H17 and 290A12, indicating the translocation disrupted NUP98. FISH restriction at 8p11-12 showed a split of BAC 350N15. Molecular investigations into candidate genes in this BAC showed the NUP98 fusion partner at 8p11.2 was the NSD3 gene. To date the NSD3 gene has never been implicated in hematologic malignancies.

Acute Disease↗
PubMed2002

Effectiveness of donor natural killer cell alloreactivity in mismatched hematopoietic transplants.

T cells that accompany allogeneic hematopoietic grafts for treating leukemia enhance engraftment and mediate the graft-versus-leukemia effect. Unfortunately, alloreactive T cells also cause graft-versus-host disease (GVHD). T cell depletion prevents GVHD but increases the risk of graft rejection and leukemic relapse. In human transplants, we show that donor-versus-recipient natural killer (NK)-cell alloreactivity could eliminate leukemia relapse and graft rejection and protect patients against GVHD. In mice, the pretransplant infusion of alloreactive NK cells obviated the need for high-intensity conditioning and reduced GVHD. NK cell alloreactivity may thus provide a powerful tool for enhancing the efficacy and safety of allogeneic hematopoietic transplantation.

Acute Disease↗
PubMed2002

Philadelphia-positive acute lymphoblastic leukemia with multiple subclones including duplication of the Philadelphia chromosome and Abelson oncogene.

A case of Philadelphia (Ph)-positive acute lymphoblastic leukemia (ALL) with multiple subclones including duplication of the BCR-ABL1 fusion gene and of the Abelson oncogene (ABL1) is reported. Cytogenetically, two different rearrangements of chromosome 9 not involved in the t(9;22) were found in two subclones. In one subclone the normal 9 was lost and replaced by an acrocentric marker, which contained an additional copy of the BCR-ABL1 fusion gene. Reverse transcriptase polymerase chain reaction detected the fusion transcripts p210 (e13a2 junction) and p190 (e1a2 junction), whereas fluorescence in situ hybridization showed the major BCR-ABL1 junction in both Ph chromosomes, strongly suggesting that the presence of the p210 and p190 proteins in this case was due to mechanisms of alternative or mis-splicing at the transcriptional level. The second subclone showed the classic t(9;22) plus an add(9)(p24) containing two copies of the ABL1 gene. Other molecular events involving chromosome 9 were a monoallelic loss of JAK2 in both subclones and an additional loss of P15/P16 in the subclone with the acrocentric marker bearing the extra Ph chromosome.

Acute Disease↗
PubMed2002

Interpretation of the complex karyotype and identification of a new 6p amplicon by integrated comparative genomic hybridization and fluorescence in situ hybridization on the U937-I cell line.

Molecular cytogenetics is helpful to identify complex and cryptic genomic changes in malignancy. Human leukemic cell lines are an important tool for advancements of biological research on malignant cells, one critical step being characterization of genomic changes. We used fluorescence in situ hybridization and comparative genomic hybridization to refine karyotypic interpretation of the diffuse histiocytic lymphoma derived U937-1 cell line. From this integrated approach, chromosome material involved in nine karyotypic markers and in unbalanced translocations could be identified. Moreover, a previously undetected amplicon emerged within band 6p21. The U937-I is a new in vitro model to study genome amplification and unknown recombinations in leukemic cells, such as those involving the centromeric region of chromosome 1.

Aneuploidy↗