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Alessandro Rambaldi

Publications and source records attributed to Alessandro Rambaldi.

At least 19 recordsLinked to original sources
PubMed2026

iMTSS: an integrated framework for biology- and patient-driven prognosis in myelofibrosis undergoing transplantation.

BACKGROUND: Allogeneic hematopoietic cell transplantation is the only curative treatment for myelofibrosis, but failure occurs by two mechanistically distinct routes: relapse of the neoplasm, which reflects its underlying genetics, and non-relapse mortality, which reflects whether the patient and graft tolerate the procedure. Established prognostic systems either lack molecular granularity or were derived in the non-transplant setting, and all collapse these two routes into a single survival estimate. None can indicate why an individual patient is at risk, or which class of intervention might reduce that risk. OBJECTIVE: To determine why an individual patient is at risk and to develop and validate an integrated framework that quantifies biology- and patient-driven prognosis. STUDY DESIGN: We analyzed 1,550 adults undergoing first allogeneic transplantation for primary or secondary myelofibrosis across international centers, the largest genomically annotated transplant cohort in this disease. The cohort was split into development (n=930) and validation (n=620) sets. Overall survival was modeled by Cox regression; relapse and non-relapse mortality were modeled as competing events by Fine-Gray subdistribution-hazard regression at 2 years. Discrimination was assessed by the concordance index with bootstrap confidence intervals. The molecular contribution was quantified by variance decomposition of, and robustness to the analytic choices was examined by resampling. RESULTS: A genetically defined disease-intrinsic axis, including TP53 allelic state, RAS pathway mutations, ASXL1 and driver genotype, blasts and blood counts, predicted 2 year relapse incidence (validation concordance 0.69, 95% CI 0.63 to 0.74), whereas a non-overlapping host and structural axis, including portal vein thrombosis, donor type, patients' performance status, and age predicted 2-year non-relapse mortality (0.63, 95% CI 0.59 to 0.68). The two scores shared only 3.4% of their variance, indicating that a patient's disease genetics carried almost no information about non-relapse mortality. Variance decomposition showed that TP53 allelic state alone accounted for 30% of the relapse score. Recombined, the framework discriminated overall survival (concordance 0.640, 95% CI 0.616 to 0.662) better than every established prognostic system. For proof of concept, 3 risk groups separated in the validation cohort, with 5 year survival of 72%, 58%, and 39% (P<0.001), and the models were well calibrated. CONCLUSIONS: Relapse and non-relapse mortality after transplantation for myelofibrosis are governed by distinct dimensions. Estimating both outcomes independently with genetic and clinical information, in addition to overall survival, establishes an individualized basis for transplant decision-making. The calculator is openly available (https://imtss-calculator.com).

mortality↗
PubMed2025

Optimized GMP-grade production of non-viral Sleeping Beauty-generated CARCIK cells for enhanced fitness and clinical scalability.

BACKGROUND: Strict adherence to GMP guidelines and regulatory compliance is crucial when transitioning from research to clinical-grade production of ATMPs like CAR T cells. The success of CAR T cell therapy in treating hematological malignancies highlights the need for closed or automated systems to ensure quality and efficacy. Recent evidence also suggests that ex vivo culture conditions can significantly impact CAR T cell functionality. METHODS: We present our optimized methodology for expanding Sleeping Beauty transposon-engineered Chimeric Antigen Receptor-Cytokine-Induced Killer (CARCIK) cells using G-Rex devices and evaluate its impact on CARCIK cell phenotype and T cell fitness. RESULTS: Building on our previously validated protocol, we introduced key simplifications to optimize the CARCIK differentiation process. Delaying the nucleofection step eliminated the need for feeder cells while maintaining efficient CAR expression and high cell viability. Transitioning from T-flasks to G-Rex bioreactors reduced operator hands-on time from 21 to 28 days to 14-17 days and resulted in a less differentiated CARCIK cell product. Metabolic and transcriptional analyses showed that the novel protocol improves CARCIK cell fitness and in vivo efficacy against B-cell lymphoma. The novel method was validated in Good Manufacturing Practices (GMP) conditions at our two Cell Factories and yielded enough numbers of CARCIK-CD19 cells for clinical use. CONCLUSIONS: Optimizing non-viral CARCIK cell production using G-Rex bioreactors and refined timing adjustments has streamlined the workflow, enhanced cell fitness, and resulted in a highly effective therapeutic product with demonstrated in vivo efficacy in mice. These improvements reduced manipulation and contamination risks, while optimizing logistics and space efficiency, facilitating allogeneic CARCIK generation for a current phase I/II clinical trial (NCT05869279) in patients with R/R CD19&#x2009;+&#x2009;non-Hodgkin Lymphoma (B-cell NHL) and Chronic Lymphocytic Leukemia (CLL), confirming the approach's scalability and clinical potential.

Humans↗
PubMed2007

Risk of thrombosis in patients with essential thrombocythemia and polycythemia vera according to JAK2 V617F mutation status.

We compared the laboratory and clinical findings of 179 patients with essential thrombocythemia (ET) and 77 with polycythemia vera (PV) classified according to the presence of the JAK2 V617F mutation. A gradient was observed in laboratory values between patients with JAK2 wild-type ET, JAK2 V617F ET and PV (all of whom carried the JAK2 mutation). The rate of thrombotic complications in JAK2-positive ET patients was significantly higher than that in wild-type ET patients and not statistically different from that in PV patients.

Adolescent↗
PubMed2006

Leukocytosis is a risk factor for thrombosis in essential thrombocythemia: interaction with treatment, standard risk factors, and Jak2 mutation status.

Leukocytes contribute to the pathogenesis of thrombosis in essential thrombocythemia (ET) through recently discovered mechanisms of activation and interaction with platelets and endothelial cells. To evaluate whether an increased leukocyte count was associated with thrombosis and whether this effect can be modulated by therapy, we analyzed the clinical course of 439 patients with ET followed at the Ospedali Riuniti di Bergamo. The strength of the association was measured at diagnosis or before thrombotic events by multivariable analyses carried out using data at baseline as well as time-varying covariates. The results showed that (1) an increased leukocyte count at diagnosis was associated with thrombosis during follow-up ("baseline analysis," relative risk [RR] 2.3, 95% confidence interval [CI] 1.4-3.9, P = .001); (2) hydroxyurea (HU) lowered leukocytosis and reduced the strength of the association between leukocytosis and thrombosis ("time-dependent analysis," RR 1.6, 95% CI 0.9-2.0, not significant [NS]); (3) the association of leukocytosis and thrombosis was more evident in untreated low-risk patients (RR 2.7, 95% CI 1.2-6.4, P = .01) compared with HU-treated high-risk patients (RR 1.6, 95% CI 0.8-3.2, NS); and (4) the presence of JAK2 V617F was not identified as a risk factor for thrombosis during follow-up despite a significant association between the mutation and leukocytosis. We suggest validation of these findings in prospective clinical studies.

Adolescent↗
PubMed2006

Results of genoidentical hemopoietic stem cell transplantation with reduced intensity conditioning for acute myelocytic leukemia: higher doses of stem cells infused benefit patients receiving transplants in second remission or beyond--the Acute Leukemia Working Party of the European Cooperative Group for Blood and Marrow Transplantation.

PURPOSE: Nucleated cell dose is an important and modifiable factor in hematopoietic stem cell transplantation (HSCT), however its association with outcomes in the context of reduced intensity conditioning regimen (RIC) HSCT for adults with acute myelocytic leukemia (AML) is not known. PATIENTS AND METHODS: From 1998 to 2003, 253 patients with de novo AML, received transplants with RIC and peripheral blood from a genoidentical donor. Median age was 55 years (range, 18 to 72) and the median follow-up was 17 months (range, 2 to 67). One hundred forty one patients received transplants in first remission (CR1), 47 received transplants in second remission (CR2), and 65 patients received transplants in a more advanced phase. Fludarabin-based RIC was used in 91% of patients and low-dose (< 4 Gy) total-body radiation in 23% of patients. The median nucleated and CD34 cell dose infused were 9.1x 10(8)/kg and 5.8x 10(6)/kg, respectively. RESULTS: Overall, 2-year leukemia-free survival (LFS) was 41% +/- 4% and it was 46% +/- 5% for patients receiving a higher cell dose (> 9.1x 10(8)/kg) and 37% +/- 5% for the remainders (P = .03). Higher cell doses exclusively benefited patients who received transplantations in CR2 or beyond, with LFS of 47 +/- 8 versus 20 +/- 8, with no detectable effect for patients who received transplants in CR1. In a multivariate analysis of the overall patient population, higher nucleated cell dose cells were associated with higher LFS (P = .04), higher incidence of chronic graft-versus-host disease (P = .01), and there was a trend towards a lower relapse incidence (P = .06). Interestingly, CD34+ cell dose was not associated with any outcomes. CONCLUSION: Nucleated cell dose is an important factor that can be modified to improve results of RIC for patients with AML transplanted later than in CR1.

Adult↗
PubMed2006

Analysis of immunoglobulin heavy and light chain variable genes in post-transplant lymphoproliferative disorders.

Post-transplant lymphoproliferative disorders (PTLD) derive from antigen-experienced B-cells and represent a major complication of solid organ transplantation. We characterized usage, mutation frequency and mutation pattern of immunoglobulin variable (IGV) gene rearrangements in 50 PTLD (polymorphic PTLD, n=10; diffuse large B-cell lymphoma, n=35; and Burkitt/Burkitt-like lymphoma, n=5). Among PTLD yielding clonal IGV amplimers, a functional IGV heavy chain (IGHV) rearrangement was found in 40/50 (80.0%) cases, whereas a potentially functional IGV light chain rearrangement was identified in 36/46 (78.3%) PTLD. By combining IGHV and IGV light chain rearrangements, 10/50 (20.0%) PTLD carried crippling mutations, precluding expression of a functional B-cell receptor (BCR). Immunohistochemistry showed detectable expression of IG light chains in only 18/43 (41.9%) PTLD. Failure to detect a functional IGV rearrangement associated with lack of IGV expression. Our data suggest that a large fraction of PTLD arise from germinal centre (GC)-experienced B-cells that display impaired BCR. Since a functional BCR is required for normal B-cell survival during GC transit, PTLD development may implicate rescue from apoptosis and expansion of B-cells that have failed the GC reaction. The high frequency of IGV loci inactivation appears to be a peculiar feature of PTLD among immunodeficiency-associated lymphoproliferations.

Apoptosis↗
PubMed2006

Clinical grade expansion of CD45RA, CD45RO, and CD62L-positive T-cell lines from HLA-compatible donors: high cytotoxic potential against AML and ALL cells.

OBJECTIVE: Identification of a clinical grade method for the ex vivo generation of donor-derived T cells cytotoxic against both myeloid and lymphoblastic cells still remains elusive. We investigated rapid generation and expansion of donor derived-allogeneic T-cell lines cytotoxic against patient leukemic cells. MATERIALS AND METHODS: Acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL) blasts were cultured 5 days in Stem Span, granulocyte macrophage colony-stimulating factor, interleukin-4, and calcium ionophore. All B-precursor ALL (N22) and AML (N13), but not T-cell ALL (N3), differentiated into mature leukemia-derived antigen-presenting cells (LD-APC). All but one LD-APC generated cytotoxic T lymphocyte (CTL) from adult human leukocyte antigen (HLA)-identical (N8) or unrelated donors (N2). RESULTS: Upon in vitro culture, donor-derived CTL acquired a memory T phenotype, showing concomitant high CD45RA, CD45RO, CD62L expression. CD8(+) cells, but not CD4(+) cells, were granzyme, perforine, and interferon-gamma-positive. Pooled CD4(+) and CD8(+) cells were cytotoxic against leukemic blasts (32%, 30:1 E:T ratio), but not against autologous or patient-derived phytohemagglutinin blasts. LD-APC from five ALL patients were used to generate CTL from cord blood. A mixed population of CD4(+) and CD8(+) cells was documented in 54% of wells. T cells acquired classical effector memory phenotype and showed a higher cytotoxicity against leukemia blasts (47%, 1:1 E:T ratio). Adult and cord blood CTL showed a skewing from a complete T-cell receptor repertoire to an oligo-clonal/clonal pattern. CONCLUSIONS: Availability of these cells should allow clinical trials for salvage treatment of leukemia patients relapsing after allogeneic stem cell transplantation.

Adolescent↗
PubMed2006

Management of nodal diffuse large B-cell lymphomas: practice guidelines from the Italian Society of Hematology, the Italian Society of Experimental Hematology and the Italian Group for Bone Marrow Transplantation.

The Italian Society of Hematology (SIE) and two affiliate societies (SIES and GITMO) commissioned a project to develop clinical practice guidelines for the treatment of nodal diffuse large B-cell non Hodgkin lymphomas (DLBCL). Key questions clinically relevant to the management of patients with nodal DLBCL were formulated by an Advisory Committee (AC) and approved by an Expert Panel (EP) composed of eight senior hematologists. After a comprehensive and systematic literature review, the EP formulated therapy recommendations and graded them according to the supporting evidence. An explicit approach to consensus methodologies was used for evidence interpretation and for producing recommendations in the absence of strong evidence. The EP formulated recommendations on which first-line therapy to choose in patients with nodal DLBCL. Patients of all ages, with stage I-II disease and no adverse prognostic factors should receive abbreviated chemotherapy with an anthracycline-containing regimen plus involved field radiotherapy (35-40 Gy). Patients with stage I-II disease and at least one adverse prognostic factor, or with stage III-IV disease, should receive frontline chemoimmunotherapy with CHOP, CHOP-like or third-generation chemotherapy plus rituximab. Recommendations on stem cell transplantation and on which therapy to adopt for refractory or relapsed patients were also formulated.

Antineoplastic Agents↗
PubMed2006

The sensitivity of acute lymphoblastic leukemia cells carrying the t(12;21) translocation to campath-1H-mediated cell lysis.

BACKGROUND AND OBJECTIVES: Campath-1H is used in conditioning regimens and more recently as an anti-leukemic therapy in acute lymphoblastic leukemias (ALL). We therefore investigated CD52 expression and campath-1H-mediated lysis of ALL cells in vitro. DESIGN AND METHODS: Complement-mediated cytotoxicity assays were performed on freshly isolated neoplastic cells and cell lines using human serum. Antibody-dependent cellular cytotoxicity (ADCC) was performed by calcein-AM release assays. RESULTS: CD52 was expressed in four out of eight ALL cell lines studied. Among 61 freshly isolated ALL samples CD52 was expressed at varying levels in 87% of cases. Whereas ADCC was equivalent in different CD52+ lines, complement-dependent cytotoxicity (CDC) was variable. The REH cell line bearing the t(12;21) translocation showed 47-60% lysis when treated with 10 microg/mL campath-1H compared to 0-6% for the other cell lines expressing equivalent amounts of CD52. Furthermore all nine ALL samples with t(12;21) showed very high CDC (mean 97%) compared to the other 24 CD52+cases (mean 24%)(p<0.0001). In t(12;21) samples, efficient CDC was obtained with as little as 1 microg/mL campath-1H. CDC correlated in part with CD52 levels, suggesting that CD52 expression and other yet undefined factors contribute to the particular sensitivity of t(12;21) cells. The resistance of non t(12;21) ALL cases could be overcome to a limited extent by increasing the concentration of campath-1H, blocking the CD55 and CD59 complement inhibitors, and more effectively by combining campath-1H with fludarabine. INTERPRETATION AND CONCLUSIONS: We conclude that most ALL samples express CD52 to a variable level and that campath-1H has cytotoxic activity against CD52+ALL, alone or in combination with cytotoxic drugs.

Adolescent↗
PubMed2005

Outcomes of reduced-intensity transplantation for chronic myeloid leukemia: an analysis of prognostic factors from the Chronic Leukemia Working Party of the EBMT.

This study reports outcomes of allogeneic hematopoietic stem cell transplantation with reduced-intensity conditioning (RIC) in 186 patients with chronic myeloid leukemia (CML) from the European Group for Blood and Marrow Transplantation (EBMT). The median age was 50 years, and 64% were in first chronic phase (CP1), CP2 13%, accelerated phase 17%, and blast crises 6%. The median EBMT transplant score was 3. The day 100 transplantation-related mortality (TRM) was 6.1% (confidence interval [CI], 3.4%-11%) but rose to 23.3% (CI, 14%-27%) at 2 years. Fludarabine, busulfan, and antithymocyte globulin (Fd/Bu/ATG) was associated with the lowest TRM of 11.6% (CI, 4.7%-11%) at 1 year. Acute graft-versus-host disease (GvHD) grade II to IV occurred in 32% and chronic GvHD in 43% (extensive in 24%). ATG was associated with a lower incidence of chronic GvHD (cGvHD). The overall survival (OS) and progression-free survival (PFS) at 3 years were 58% (CI, 50%-66%) and 37% (CI, 30%-45%), respectively. Adverse OS was associated with advanced disease (relative risk [RR], 3.4). PFS was inferior in advanced disease (RR, 2.7) and a trend to improved outcomes with Fd/Bu/ATG (RR, 0.58). RIC allografts are feasible in CML in first or second CP. Since no other RIC regimen demonstrated superiority, Fd/Bu/ATG should be considered as baseline in future prospective trials.

Adolescent↗
PubMed2005

Quantitative PCR of bone marrow BCL2/IgH+ cells at diagnosis predicts treatment response and long-term outcome in follicular non-Hodgkin lymphoma.

By real-time quantitative polymerase chain reaction (RQ-PCR), we evaluated BCL2/IgH(+) cells in the bone marrow (BM) and peripheral blood (PB) from 86 patients with follicular lymphoma treated with the sequential administration of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) and rituximab. At diagnosis, the amount of BCL2/IgH(+) cells in the BM was low (1 BCL2/IgH(+) cell in 1000-100 000 normal cells) in 43% of patients, intermediate (1 in 100-1000) in 34%, and high (> 1 in 100) in 23%. A 2 log decrease of BCL2/IgH(+) cells was achieved after CHOP and an additional 2 log reduction following rituximab. By multivariate analysis, a low level of BCL2/IgH(+) cells in the BM at diagnosis was the best predictor for the achievement of a complete clinical and molecular response. At 5 years, the event-free survival rates of patients with a low/intermediate or high tumor infiltration in the BM were 59% and 32%, respectively. The freedom from recurrence of patients who achieved a molecular response in the BM, no matter whether after CHOP alone or CHOP and rituximab, was 64% as compared to 32% for patients who did not (P < .006). RQ-PCR performed at presentation on BM samples predicts treatment response and long-term clinical outcome in patients with follicular lymphoma.

Adult↗
PubMed2005

Management of nodal indolent (non marginal-zone) non-Hodgkin's lymphomas: practice guidelines from the Italian Society of Hematology, Italian Society of Experimental Hematology and Italian Group for Bone Marrow Transplantation.

The Italian Society of Hematology (SIE) and the two affiliated societies (SIES and GITMO) commissioned a project to develop clinical practice guidelines for the treatment of nodal indolent non-Hodgkin's lymphomas (NHL). Key questions clinically relevant to the management of patients with nodal indolent NHL were formulated by an Advisory Committee and approved by an Expert Panel composed of eight senior hematologists. After a comprehensive, systematic review of the literature, the Expert Panel formulated therapy recommendations and graded them according to the supporting evidence. An explicit approach to consensus methodologies was used for evidence interpretation and for providing recommendations based on poor evidence. The Expert Panel formulated recommendations on when to start a lymphoma-specific therapy, which first-line therapy to choose and which therapy to adopt for patients with relapsed, refractory and transformed disease. Treatment deferral was recommended for patients with stage III-IV disease without systemic symptoms, high tumor burden, extranodal disease, cytopenia due to marrow involvement, leukemic phase, serous effusion and high lactate dehydrogenase levels. Patients with stage I-II disease and a low tumor burden should receive frontline external involved-field radiotherapy, while patients with a high tumor burden or a severe prognostic score should receive front-line chemotherapy plus involved-field radiotherapy. Younger patients with stage III-IV disease should receive front-line therapy with anthracycline- or fludarabine-based regimens combined with rituximab, while older patients who are candidates for treatment should receive single-agent alkylating therapy. By using a systematic literature review and an explicit approach to consensus among experts, recommendations for the key therapeutic decisions in patients with nodal indolent NHL are provided.

Bone Marrow Transplantation↗
PubMed2005

Feasibility and outcome of tandem stem cell autotransplants in multiple myeloma.

BACKGROUND AND OBJECTIVES: Clinical trials have shown that high dose chemotherapy (HDT) with peripheral stem cell autotransplantation is presently the best treatment for patients with symptomatic multiple myeloma (MM). In the context of an outcomes research project, we analyzed the feasibility of this strategy in clinical practice in a large cohort of consecutive, unselected patients with newly diagnosed MM and looked at the major determinants of response of patients enrolled in a HDT with tandem autotransplantation (Total Therapy I, TTI) program. DESIGN AND METHODS: Two hundred and fourteen patients were treated outside of a clinical trial and regularly followed-up at our Center for symptomatic MM. Ninety-seven patients (45%) received conventional chemo-radiotherapy regimens, 110 (51%) entered the TTI program and the remaining 7 patients (3.3%) were enrolled in other programs involving HDT with autotransplantation. RESULTS: Patients enrolled in HDT with tandem autotransplantation programs were 14 years younger and less likely to have co-morbidities than patients treated with conventional therapy. Median overall survivals of the two groups were 60 and 33 months, respectively. Thirteen percent of the patients enrolled in the TTI program did not receive the first HDT with autotransplantation, mostly because of disease progression, and another 16% did not proceed to the second HDT with autotransplantation mainly because of infections or drug-related complications. Most patients achieved complete remission after the second autotransplantation, with acceptable toxicity. However, only patients with a major reduction of the myeloma burden at the end of induction therapy enjoyed significantly prolonged event-free and overall survivals. INTERPRETATION AND CONCLUSIONS: Approximately one third of patients with newly diagnosed symptomatic MM completed the TTI program. These data suggest the need to improve the induction therapy in order to increase both the number of patients able to proceed to autotransplantation programs and to enhance the rate of early response.

Adult↗
PubMed2004

Phosphodiesterase IV inhibition by piclamilast potentiates the cytodifferentiating action of retinoids in myeloid leukemia cells. Cross-talk between the cAMP and the retinoic acid signaling pathways.

Inhibition of phosphodiesterase IV by N-(3,5-dichloropyrid-4-yl)-3-cyclopentyloxy-4-methoxybenzamide (piclamilast) enhances the myeloid differentiation induced by all-trans-retinoic acid (ATRA), retinoic acid receptor alpha (RARalpha), or retinoic acid receptor X agonists in NB4 and other retinoid-sensitive myeloid leukemia cell types. ATRA-resistant NB4.R2 cells are also partially responsive to the action of piclamilast and retinoic acid receptor X agonists. Treatment of NB4 cells with piclamilast or ATRA results in activation of the cAMP signaling pathway and nuclear translocation of cAMP-dependent protein kinase. This causes a transitory increase in cAMP-responsive element-binding protein phosphorylation, which is followed by down-modulation of the system. ATRA + piclamilast have no additive effects on the modulation of the cAMP pathway, and the combination has complex effects on cAMP-regulated genes. Piclamilast potentiates the ligand-dependent transactivation and degradation of RARalpha through a cAMP-dependent protein kinase-dependent phosphorylation. Enhanced transactivation is also observed in the case of PML-RARalpha. In NB4 cells, increased transactivation is likely to be at the basis of enhanced myeloid maturation and enhanced expression of many retinoid-dependent genes. Piclamilast and/or ATRA exert major effects on the expression of cEBP and STAT1, two types of transcription factors involved in myeloid maturation. Induction and activation of STAT1 correlates directly with enhanced cytodifferentiation. Finally, ERK and the cAMP target protein, Epac, do not participate in the maturation program activated by ATRA + piclamilast. Initial in vivo studies conducted in severe combined immunodeficiency mice transplanted with NB4 leukemia cells indicate that the enhancing effect of piclamilast on ATRA-induced myeloid maturation translates into a therapeutic benefit.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2004

Suicide gene therapy and the control of graft-vs-host disease.

Allogeneic bone marrow transplantation as a cure for leukaemia and lymphoma is limited by the development of graft-vs-host disease (GVHD), an immunological reaction of the donor's T lymphocytes against the host's normal tissues. One therapeutic option to treat GVHD is the transfer of 'suicide' genes into the donor's T lymphocytes to render them susceptible to prodrug administration. This procedure should permit the elimination of unwanted T lymphocytes in GVHD. The main genes proposed for such a strategy will be described in this chapter, together with the advantages and limitations found during preclinical and clinical studies to date.

Bone Marrow Transplantation↗
PubMed2004

Incidence of novel N-glycosylation sites in the B-cell receptor of lymphomas associated with immunodeficiency.

Novel N-glycosylation sites are introduced by somatic mutation into the V genes of the majority of follicular lymphomas. Sites are positively selected and rare in normal memory B cells, indicating a potential role in tumour survival in the germinal centre (GC). The incidence of c. 40% in diffuse large B-cell lymphomas (DLBCL) parallels the known heterogeneity of the disease. Immunodeficiency-related non-Hodgkin's lymphomas (NHL) include post-transplant lymphoproliferative disorders (PTLD) and acquired immunodeficiency syndrome-related NHL (AIDS-NHL). Most PTLD derive from B cells that carry mutated VH genes and that have completed the GC reaction. All AIDS-NHL carry mutated VH genes and variable features of GC or post-GC cells. To determine if N-glycosylation is a feature of immunodeficiency-related lymphomas, we analysed the VH genes of 19 PTLD and 36 AIDS-NHL. Novel sites were rare in PTLD (4/19), similar to memory B cells (P = 0.15). AIDS-NHL, including DLBCL and Burkitt's lymphomas (BL), showed heterogeneity with 16 of 36 (44%) having novel sites. The findings indicate no selection of N-glycosylation sites in PTLD, consistent with post-GC features. The variable incidence of N-glycosylation sites in AIDS-NHL mirrors that in DLBCL and sporadic BL of immunocompetent hosts, supporting the known heterogeneity of these disorders, and possibly pointing to distinct routes of tumour development.

Gene Rearrangement, B-Lymphocyte↗
PubMed2004

Treatment of severe aplastic anemia with antilymphocyte globulin, cyclosporine and two different granulocyte colony-stimulating factor regimens: a GITMO prospective randomized study.

BACKGROUND AND OBJECTIVES: In a previous study we showed that patients with severe aplastic anemia (SAA) treated with anti-lymphocyte globulin (ALG), cyclosporin (CyA) and granulocyte colony-stimulating factor (G-CSF) 5 micro g/kg/day had an encouraging outcome. However, failure to respond, delayed responses, partial responses, relapses and early deaths remain significant problems. The aim of the present study was to test whether a higher dose of G-CSF (10 micro g/kg/day) would reduce these complications. DESIGN AND METHODS: This was a multicenter prospective trial in 77 SAA patients treated with horse ALG (15 mg/kg/day day1-5) and CyA (5 mg/kg/day day 1-180). Patients were randomized to receive G-CSF 5 micro g/kg/day (n=38, group A) or 10 micro g/kg/day (n=39, group B) from day +1 to day +30. All patients then received G-CSF 5 micro g/kg/day from day +31 to day +90. The primary end point of this study was response at day +120. Secondary end points were early deaths, blood counts at day +120, and survival. RESULTS: At day +120 responses were classified as absent, partial, and complete in 12, 22, and 4 patients in group A and in 23, 7, and 9 patients in group B (p=0.001). At last follow-up these figures were respectively 9, 12, and 17 vs 19, 2, and 18 (p=0.004). Thirteen patients (5 in group A and 8 in group B) died before day 120 (p=0.3). Median peripheral blood counts on day 120 were comparable in the two groups: Hb 10.5 and 9.5 g/dL in group A and B, respectively (p=0.6), Neutrophil counts were 2.4 vs 1.9x10(9)/L in groups A and B (p=0.4) and platelet counts were, respectively, 42 vs 36x10(9)/L (p=0.3). The actuarial survival at 4 years is 72% in group A and 67% in group B (p=0.3). INTERPRETATION AND CONCLUSIONS: Increasing the dose of G-CSF does not appear to reduce early deaths, does not improve peripheral blood counts nor survival, and may reduce the response rate in patients with SAA receiving ALG and CyA.

Adolescent↗