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Marco Bregni

Publications and source records attributed to Marco Bregni.

15 recordsLinked to original sources
PubMed2006

Killer cell Ig-like receptors ligand-mismatched, alloreactive natural killer cells lyse primary solid tumors.

BACKGROUND: Donor alloreactive natural killer (NK) cells have a potent antileukemic effect in haploidentical stem cell transplantation. Whether alloreactive NK cells are able to specifically kill fresh tumor cells from primary solid tumors was analyzed. METHODS: NK cells were purified from healthy donors for the expression of inhibitory killer cell immunoglobulin (Ig)-like receptors (KIRs), ex vivo expanded, and used as effector cells. Their cytotoxic effect on tumor cells freshly obtained from surgical specimens was assessed by means of a single-cell cytotoxic assay (SCCA). RESULTS: Tumor cells from 1 ovarian, 1 gastric, 3 colon, and 4 renal cell cancers were analyzed and found susceptible to alloreactive NK cell killing (>20% lysis at an effector cell to target cell [E:T] ratio of 10:1 for tumor cells not expressing at least 1 human lymphocyte antigen [HLA] class I KIR-ligand group). Remarkably, NK cells that recognized specific HLA-C group mismatches were able to kill HLA-C KIR ligand-mismatched tumor cells, whereas no lysis of target cells occurred with KIR ligand-matched tumor targets. CONCLUSIONS: Alloreactive NK-cell mediated antitumor effects might provide useful insights for designing new cell therapy approaches against solid tumors.

Antineoplastic Agents↗
PubMed2006

Variations of the perforin gene in patients with autoimmunity/lymphoproliferation and defective Fas function.

Mutations decreasing function of the Fas death receptor cause the autoimmune lymphoproliferative syndrome (ALPS) with autoimmune manifestations, spleen/lymph node enlargement, and expansion of CD4/CD8-negative T cells. Dianzani Autoimmune Lymphoproliferative Disease (DALD) is a variant lacking this expansion. Perforin is involved in cell-mediated cytotoxicity and its biallelic mutations cause familial hemophagocytic lymphohistiocytosis (HLH). We previously described an ALPS patient carrying heterozygous mutations of the Fas and perforin genes and suggested that they concurred in ALPS. This work extends the analysis to 14 ALPS, 28 DALD, and 816 controls, and detects an N252S amino acid substitution in 2 ALPS, and an A91V amino acid substitution in 6 DALD. N252S conferred an OR = 62.7 (P = .0016) for ALPS and A91V conferred an OR = 3 (P = .016) for DALD. Copresence of A91V and variations of the osteopontin gene previously associated with DALD conferred an OR = 17 (P = .0007) for DALD. In one N252S patient, NK activity was strikingly defective in early childhood, but became normal in late childhood. A91V patients displayed lower NK activity than controls. These data suggest that perforin variations are a susceptibility factor for ALPS/DALD development in subjects with defective Fas function and may influence disease expression.

Amino Acid Substitution↗
PubMed2006

Direct intramyocardial percutaneous delivery of autologous bone marrow in patients with refractory myocardial angina.

BACKGROUND: Intramyocardial injection of autologous bone marrow (ABM) may induce angiogenesis. We tested the safety and feasibility of catheter-based direct percutaneous intramyocardial delivery of ABM in patients with refractory angina pectoris. METHODS: Ten patients (9 men, 67 +/- 8 years) with refractory angina (Canadian Cardiovascular Society class III-IV) and documented myocardial ischemia were enrolled. After left ventricular electromechanical mapping, freshly aspirated and filtered ABM was percutaneously injected into target myocardial ischemic areas. Clinical symptoms (as assessed according to the Canadian Cardiovascular Society class), quality of life, and myocardial perfusion were evaluated before the procedure and through the follow-up. RESULTS: In all patients, ABM was successfully injected into the target regions. No periprocedural complications occurred. At 12 months, no major cardiac events (death, acute myocardial infarction, stroke, and malignant ventricular arrhythmias) occurred. Severity of angina improved of > or = 2 classes in 3 patients. Quality of life showed a significant improvement in all patients. Myocardial perfusion in the target regions improved in 4 of 8 patients. CONCLUSIONS: Direct percutaneous intramyocardial delivery of ABM appears feasible and safe. Further evaluation is warranted to test its clinical efficacy.

Aged↗
PubMed2006

Therapeutic and diagnostic applications of minor histocompatibility antigen HA-1 and HA-2 disparities in allogeneic hematopoietic stem cell transplantation: a survey of different populations.

Minor histocompatibility antigens (mHags) HA-1 and HA-2 are encoded by biallelic loci, with immunogenic variants, HA-1H and HA-2V, which induce strong HLA-A2-restricted alloreactive T-cell responses, and nonimmunogenic counterparts, HA-1R and HA-2M, which represent functional null alleles that are poorly presented by HLA class I molecules. HA-1 and HA-2 are potential targets of selective graft-versus-leukemia and graft-versus-tumor reactivity after allogeneic hematopoietic stem cell transplantation (HSCT); however, these applications are restricted to a limited number of patients. Here, we show that a far more frequent application of HA-1 and HA-2 disparity relies on their use as markers for the state of host chimerism after allogeneic HSCT. We have determined allelic frequencies of 29.3% and 70.7% for HA-1H and HA-1R, respectively, and of 83.7% and 16.3% for HA-2V and HA-2M, respectively, in >200 healthy individuals from northern Italy. Similar frequencies were observed in nearly 100 patients affected by hematologic malignancies or solid tumors, thus showing that HA-1 and HA-2 variability are not associated with the presence of cancer. On the basis of these data, we predict that HA-1 and HA-2 can be used in 32.8% and 23.5% of Italian transplant patients, respectively, as markers for the state of host chimerism, whereas exploitation of disparity for these mHags for targeted immunotherapy will be possible in 10.7% and 1.1% of Italian patients, respectively. Retrospective HA-2 typing of bone marrow aspirates obtained from a patient during complete remission or recurrence of acute myeloid leukemia after haploidentical HSCT showed the feasibility of using HA-2 as a surrogate marker for disease monitoring. Because of an apparent north-south gradient for HA-1 allelic frequencies, with higher frequencies for the HA-1H variant reported in white populations from Southern Europe as compared with Northern Europe and North America, the diagnostic applicability of HA-1 disparity will be slightly more frequent in transplant patients from the north. Taken together, our data show that determination of HA-1 and HA-2 variability can be an important parameter for the selection of allogeneic stem cell donors, in particular for patients affected by hematologic malignancies without a tumor-specific molecular marker.

Biomarkers↗
PubMed2006

Long-term results of a risk-adapted approach to melphalan conditioning in autologous peripheral blood stem cell transplantation for primary (AL) amyloidosis.

BACKGROUND AND OBJECTIVES: High-dose melphalan with autologous peripheral blood stem cell transplantation (ASCT) is an effective treatment for systemic primary amyloidosis. This procedure is, however, associated with substantial toxicity and mortality, particularly if the heart is involved. Refined selection of patients suitable for transplantation and personalized adaptation of the doses of melphalan might improve the outcome. DESIGN AND METHODS: Twenty-two consecutive patients were selected for age, number of organ systems involved, heart and kidney function, and treated with risk-adapted melphalan conditioning. This was first-line therapy in 81% of cases. RESULTS: Fifty-five percent of the patients had amyloid involvement of two organ systems, with renal involvement predominant in half. Approximately 70% received full-dose melphalan. Toxicity was manageable and three transplant-related deaths (14%) occurred only in the early phase of the study. The median overall survival was 68 months. The intent-to-treat hematologic response rate was 55% at +12 months (complete, 36%; partial, 19%), which was accompanied by organ responses in 75%. Survival was positively influenced by: (i) hematologic response at +3 months (complete+partial responses 55%, median not reached, more than 108 months; no response, median 17 months) (p=0.001); (ii) amyloid involvement of a single organ system (p=0.016). Prolonged follow-up demonstrated that remissions are durable, but relapses may occur as 4 of 12 responsive patients (33%) relapsed, three from complete response, between +30 to +38 months. INTERPRETATION AND CONCLUSIONS: The present risk-adapted approach produced acceptable toxicity and peri-transplant mortality with prolonged survival in responsive patients. Additional therapy should be considered if no hematologic response is observed at +3 months after ASCT.

Adult↗
PubMed2005

Prognostic factors for survival in patients with advanced renal cell carcinoma undergoing nonmyeloablative allogeneic stem cell transplantation.

BACKGROUND: The objective of this study was to identify prognostic factors for predicting survival in patients with advanced renal cell carcinoma (RCC) who had undergone an allogeneic stem cell transplantation after failure on immunotherapy. METHODS: The authors studied 70 patients with advanced RCC who underwent allogeneic transplantation with a fludarabine-based, reduced-intensity regimen. Ten parameters were analyzed at the time of transplantation for their power to predict survival. Clinical features were examined first univariately; then, variables that were correlated significantly with survival in the univariate analysis were included in a multivariate Cox regression model. RESULTS: Factors that were found to be associated significantly with limited survival were performance status, the number of metastatic sites, the presence of mediastinal metastasis, hemoglobin level, C-reactive protein (CRP) level, lactate dehydrogenase (LDH) level, and neutrophil counts. All these variables were included in a multivariate Cox regression model, and three were retained in the final model. Patients were classified according to the score estimated by the final Cox model in two groups (above or below the median value): The median survival was 3.5 months for patients who had a poor prognosis patients versus 23 months for patients who had a good prognosis. CONCLUSIONS: The current findings suggested that three easily available parameters (performance status, CRP level, and LDH level) could be used to stratify patients with advanced RCC who are candidates for allografting and to assist clinicians in decision-making and selection of an appropriate treatment program.

C-Reactive Protein↗
PubMed2005

A proportion of patients with lymphoma may harbor mutations of the perforin gene.

Perforin mutations have been demonstrated in a proportion of patients diagnosed with the familial form of hemophagocytic lymphohistiocytosis (HLH). In the present study, we evaluated whether some patients with lymphoma sharing clinical characteristics with HLH might harbor mutations of the perforin gene. We analyzed 29 patients and found that 4 patients, who developed either Hodgkin or non-Hodgkin lymphoma, had biallelic mutations of the perforin gene. One of these 4 patients, a 19-year-old female with T-cell lymphoma, had a brother carrying the same mutations who developed HLH. In 2 of the 4 patients with biallelic mutations of the perforin gene, we evaluated perforin expression by flow cytometry and natural killer (NK) activity and both were found to be absent. Moreover, we documented the presence of monoallelic mutations of the perforin gene in 4 more patients. One of these 4 latter patients also carried a mutation of the Fas gene. These data indicate that perforin deficiency, either alone or in combination with other mutations of genes involved in lymphocyte survival or functional activity, may be present in patients with lymphoma. These findings suggest that perforin also plays a key role in the mechanisms of immune surveillance that prevent tumor growth and/or development.

Adolescent↗
PubMed2004

Inherited perforin and Fas mutations in a patient with autoimmune lymphoproliferative syndrome and lymphoma.

A 27-year-old man with the autoimmune lymphoproliferative syndrome and a large-B-cell lymphoma had heterozygous mutations in the Fas and perforin (Prf1) genes. The Fas mutation was inherited from his healthy father and was also carried by his healthy brother, whereas the Prf1 mutation was inherited from his healthy mother. The combined effect of the two mutant genes may have contributed to the development of the autoimmune lymphoproliferative syndrome and lymphoma in this patient.

Adult↗
PubMed2004

Allogeneic stem cell transplantation for the treatment of advanced solid tumors.

Allogeneic stem cell transplantation has emerged as a potentially curative treatment modality for patients with hematological malignancies. The graft-versus-leukemia effect, an immune mechanism mediated by the donor immune system, is an important component of the therapeutic effect of allogeneic transplantation. Recent data from experimental animal models and from preliminary clinical experience suggest that a graft-versus-tumor effect, analogous to the graft-versus-leukemia effect, may be generated against solid tumors such as renal cell cancer, breast cancer, and other malignancies. The use of non-myeloablative, immunosuppressive conditioning regimens offers the opportunity to achieve a full-donor engraftment with reduced transplant-related complications and mortality, enabling also patients of advanced age and with co-morbidities to receive an allografting. Advanced renal cell cancer, an essentially incurable disease, has emerged from pilot studies as a disease susceptible to the graft-versus-tumor effect. Future studies will demonstrate if the tumor responses observed after allografting will translate into a clinically meaningful survival advantage. Other tumors in which tumor responses have been observed are: breast cancer, ovarian cancer, colorectal cancer, soft-tissue sarcoma, and others. Advanced melanoma may not be amenable to graft-versus-tumor effect. Future studies will point to the identification, isolation and cloning of target antigen(s) of graft-versus-tumor effect, to further reduce toxicities and to achieve a selective cell-mediated immunotherapy.

Animals↗
PubMed2004

Graft-versus-lymphoma effect in relapsed peripheral T-cell non-Hodgkin's lymphomas after reduced-intensity conditioning followed by allogeneic transplantation of hematopoietic cells.

PURPOSE: Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of malignancies characterized by a poor prognosis. We performed a pilot study to investigate the role of reduced-intensity conditioning (RIC) followed by allogeneic stem-cell transplantation in relapsed or refractory PTCLs. PATIENTS AND METHODS: We have conducted a phase II trial on 17 patients receiving salvage chemotherapy followed by RIC and allogeneic transplantation of hematopoietic cells. The RIC regimen consisted of thiotepa, fludarabine, and cyclophosphamide. The acute graft-versus-host disease prophylaxis consisted of cyslosporine and short course methotrexate. RESULTS: Patients had a median age of 41 years (range, 23 to 60 years). Two patients were primary chemorefractory, and 15 had relapsed disease; eight patients (47%) had a disease relapse after an autologous transplantation. After a median follow-up of 28 months from the day of study entry (range, 3 to 57 months), 14 of 17 patients were alive (12 in complete remission, one in partial remission, and one with stable disease), two died as a result of progressive disease, and one died as a result of sepsis concomitant to acute graft-versus-host disease. The estimated 3-year overall and progression-free survival rates were 81% (95% CI, 62% to 100%) and 64% (95% CI, 39% to 89%), respectively. The estimated probability of nonrelapse mortality at 2 years was 6% (95% CI, 1% to 17%). Donor lymphocyte infusions induced a response in two patients progressing after allografting. CONCLUSION: RIC followed by allogeneic stem-cell transplantation is feasible, has a low treatment-related mortality, and seems to be a promising salvage treatment for relapsed PTCL. These findings suggest that the existence of a graft-versus-T-cell lymphoma effect.

Adult↗
PubMed2004

Mobilized blood CD34+ cells transduced and selected with a clinically applicable protocol reconstitute lymphopoiesis in SCID-Hu mice.

We developed a clinically applicable gene transfer procedure into mobilized peripheral blood (MPB) CD34(+) hematopoietic progenitor cells, based on single viral exposure and selection of engineered cells. CD34(+) cells were transduced with a retroviral vector carrying the truncated form of the nerve growth factor receptor (Delta NGFR) marker gene, and immunoselected for Delta NGFR expression. Optimal time and procedure for viral exposure, length of culture, and transgene expression of MPB CD34(+) cells were determined using in vitro assays. The multipotent capacity of MPB CD34(+)-transduced cells was demonstrated in the SCID-hu bone/liver/thymus mouse model. Transduced Delta NGFR(+) cells retained 50% of long-term culture-colony forming cells (LTC-CFC) compared to unmanipulated CD34(+) cells. In SCID-hu mice, 52% of CD45(+) cells, 27% of CD34(+) cells, 49% of B cells, and more than 50% of T cells were derived from transplanted CD34(+)/Delta NGFR(+) cells. Furthermore, transplantation of purified transduced cells greatly reduced the competition with untransduced progenitors occurring in unselected grafts. These data demonstrate that MPB CD34(+) cells, transduced with a single viral exposure and selected by transgene expression, retain multilineage reconstitution capacity and remarkable transgene expression.

Animals↗
PubMed2002

Nonmyeloablative conditioning followed by hematopoietic cell allografting and donor lymphocyte infusions for patients with metastatic renal and breast cancer.

The feasibility and toxicity of allogeneic stem cell transplantation after nonmyeloablative conditioning including thiotepa, fludarabine, and cyclophosphamide have been investigated in 6 patients with breast cancer and 7 patients with renal cell cancer. The program included the use of escalating doses of donor lymphocyte infusions (DLI) and/or interferon alpha (IFNalpha) for patients showing no tumor response and no graft-versus-host disease (GVHD). Patients were at high risk of transplant-related mortality (TRM) because of age, advanced stage, and previous treatments. We observed a partial remission in 4 renal cancer and in 2 breast cancer patients (one at the molecular level in the bone marrow), occurring after cyclosporine withdrawal or after DLI and/or IFNalpha. All the responses were accompanied by the occurrence of acute GVHD. We conclude that reduced-intensity allogeneic stem cell transplantation is a feasible procedure in renal and breast cancer, and that the exploitation of graft-versus-tumor effect after DLI is a promising finding.

Adolescent↗
PubMed2002

Reduced-intensity conditioning followed by allografting of hematopoietic cells can produce clinical and molecular remissions in patients with poor-risk hematologic malignancies.

A reduced-intensity conditioning regimen was investigated in 45 patients with hematologic malignancies who were considered poor candidates for conventional myeloablative regimens. Median patient age was 49 years. Twenty-six patients previously failed autologous transplantation, and 18 patients had a refractory disease at the time of transplantation. In order to decrease nonrelapse mortality, and enhance the graft-versus-tumor effect, a program was designed in which a reduced conditioning with thiotepa, fludarabine, and cyclophosphamide was associated with programmed reinfusions of donor lymphocytes for patients without graft-versus-host disease (GVHD), not achieving clinical and molecular remission after transplantation. GVHD prophylaxis consisted of cyclosporine A and methotrexate. Seventeen patients received marrow cells and 28 received mobilized hematopoietic cells. All patients engrafted. The probability of grades II-IV and III-IV acute GVHD were 47% and 13%, respectively. The probability of nonrelapse mortality, progression-free survival, and overall survival were 13%, 57%, and 53%, respectively. Thirteen patients in complete remission had a polymerase chain reaction marker for minimal disease monitoring; 10 achieved molecular remission after transplantation. Nine patients received donor lymphocytes: one patient with mantle cell lymphoma had a minimal response, one patient with refractory anemia with excess of blasts in transformation achieved complete remission, and 7 patients did not respond. At a median follow-up of 385 days (range, 24 to 820 days), 25 patients (55%) were alive in complete remission. Although longer follow-up is needed to evaluate the long-term outcome, the study shows that this regimen is associated with a durable engraftment, has a low nonrelapse mortality rate, and can induce clinical and molecular remissions.

Adult↗