RESUMO
BACKGROUND: In an analysis of the primary outcome of this phase 3 trial, patients with early relapsed or refractory large B-cell lymphoma who received axicabtagene ciloleucel (axi-cel), an autologous anti-CD19 chimeric antigen receptor T-cell therapy, as second-line treatment had significantly longer event-free survival than those who received standard care. Data were needed on longer-term outcomes. METHODS: In this trial, we randomly assigned patients with early relapsed or refractory large B-cell lymphoma in a 1:1 ratio to receive either axi-cel or standard care (two to three cycles of chemoimmunotherapy followed by high-dose chemotherapy with autologous stem-cell transplantation in patients who had a response). The primary outcome was event-free survival, and key secondary outcomes were response and overall survival. Here, we report the results of the prespecified overall survival analysis at 5 years after the first patient underwent randomization. RESULTS: A total of 359 patients underwent randomization to receive axi-cel (180 patients) or standard care (179 patients). At a median follow-up of 47.2 months, death had been reported in 82 patients in the axi-cel group and in 95 patients in the standard-care group. The median overall survival was not reached in the axi-cel group and was 31.1 months in the standard-care group; the estimated 4-year overall survival was 54.6% and 46.0%, respectively (hazard ratio for death, 0.73; 95% confidence interval [CI], 0.54 to 0.98; P = 0.03 by stratified two-sided log-rank test). This increased survival with axi-cel was observed in the intention-to-treat population, which included 74% of patients with primary refractory disease and other high-risk features. The median investigator-assessed progression-free survival was 14.7 months in the axi-cel group and 3.7 months in the standard-care group, with estimated 4-year percentages of 41.8% and 24.4%, respectively (hazard ratio, 0.51; 95% CI, 0.38 to 0.67). No new treatment-related deaths had occurred since the primary analysis of event-free survival. CONCLUSIONS: At a median follow-up of 47.2 months, axi-cel as second-line treatment for patients with early relapsed or refractory large B-cell lymphoma resulted in significantly longer overall survival than standard care. (Funded by Kite; ZUMA-7 ClinicalTrials.gov number, NCT03391466.).
Assuntos
Antineoplásicos Imunológicos , Produtos Biológicos , Linfoma Difuso de Grandes Células B , Humanos , Antígenos CD19/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Análise de SobrevidaRESUMO
ABSTRACT: Posttransplant lymphoproliferative disorder (PTLD) is a rare complication of solid organ transplantation, and cytotoxic chemotherapy is associated with treatment-related morbidity and mortality. Current treatment takes a sequential, risk-stratified approach, and patients with low-risk disease after initial immunotherapy can avoid escalation to immunochemotherapy. TIDaL is a prospective, single-arm phase 2 trial investigating the activity and tolerability of ibrutinib combined with risk-stratified therapy for first-line treatment of PTLD. Eligible patients were adults with newly diagnosed CD20+ B-cell PTLD after solid organ transplant and performance status 0 to 2. Initial treatment comprised 49 days of ibrutinib 560 mg once daily, with 4 doses of weekly rituximab. Treatment response on interim scan and baseline International Prognostic Index were used to allocate patients to either a low-risk arm (who continued ibrutinib, alongside 4 further doses of 3-weekly rituximab) or high-risk (escalation to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone [R-CHOP] immunochemotherapy, with ibrutinib continuing in patients aged <65 years). The primary outcome was complete response on interim scan, achieved by 11 of 38 patients (29%; 95% confidence interval [CI], 15-46). This did not reach the prespecified threshold for clinically significant activity. Secondary outcomes included allocation to the low-risk arm (41% of patients), 2-year progression-free survival (58%; 95% CI, 44-76), and 2-year overall survival (76%; 95% CI, 63-91). Adverse events were mostly hematological, gastrointestinal, and infective. Although TIDaL does not support adding ibrutinib into first-line treatment of PTLD, increasing the proportion of patients who can be treated without cytotoxic chemotherapy remains an important aim of future research. This trial was registered at www.clinicaltrials.gov as #ISRCTN32667607.
Assuntos
Adenina , Protocolos de Quimioterapia Combinada Antineoplásica , Transtornos Linfoproliferativos , Piperidinas , Rituximab , Humanos , Piperidinas/uso terapêutico , Piperidinas/efeitos adversos , Piperidinas/administração & dosagem , Pessoa de Meia-Idade , Feminino , Masculino , Adenina/análogos & derivados , Adenina/uso terapêutico , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/etiologia , Idoso , Adulto , Rituximab/efeitos adversos , Rituximab/administração & dosagem , Rituximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Transplante de Órgãos/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Ciclofosfamida/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/uso terapêutico , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Doxorrubicina/administração & dosagem , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Estudos Prospectivos , Pirazóis/uso terapêutico , Pirazóis/efeitos adversos , Pirazóis/administração & dosagemRESUMO
ABSTRACT: A reciprocal t(3;8) BCL6::MYC fusion is common in large B-cell lymphoma (LBCL) with MYC and BCL6 disruption. These pseudo-double-hit cases are not adverse, whereas t(3;8)-MYC/BCL6 lymphoma has an inferior prognosis relative to other MYC-rearranged LBCL.
Assuntos
Linfoma Difuso de Grandes Células B , Proteínas Proto-Oncogênicas c-bcl-6 , Proteínas Proto-Oncogênicas c-myc , Translocação Genética , Humanos , Proteínas Proto-Oncogênicas c-bcl-6/genética , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-myc/genética , Idoso , Prognóstico , Rearranjo Gênico , Adulto , Idoso de 80 Anos ou mais , Proteínas de Fusão Oncogênica/genéticaRESUMO
BACKGROUND: The prognosis of patients with early relapsed or refractory large B-cell lymphoma after the receipt of first-line chemoimmunotherapy is poor. METHODS: In this international, phase 3 trial, we randomly assigned, in a 1:1 ratio, patients with large B-cell lymphoma that was refractory to or had relapsed no more than 12 months after first-line chemoimmunotherapy to receive axicabtagene ciloleucel (axi-cel, an autologous anti-CD19 chimeric antigen receptor T-cell therapy) or standard care (two or three cycles of investigator-selected, protocol-defined chemoimmunotherapy, followed by high-dose chemotherapy with autologous stem-cell transplantation in patients with a response to the chemoimmunotherapy). The primary end point was event-free survival according to blinded central review. Key secondary end points were response and overall survival. Safety was also assessed. RESULTS: A total of 180 patients were randomly assigned to receive axi-cel and 179 to receive standard care. The primary end-point analysis of event-free survival showed that axi-cel therapy was superior to standard care. At a median follow-up of 24.9 months, the median event-free survival was 8.3 months in the axi-cel group and 2.0 months in the standard-care group, and the 24-month event-free survival was 41% and 16%, respectively (hazard ratio for event or death, 0.40; 95% confidence interval, 0.31 to 0.51; P<0.001). A response occurred in 83% of the patients in the axi-cel group and in 50% of those in the standard-care group (with a complete response in 65% and 32%, respectively). In an interim analysis, the estimated overall survival at 2 years was 61% in the axi-cel group and 52% in the standard-care group. Adverse events of grade 3 or higher occurred in 91% of the patients who received axi-cel and in 83% of those who received standard care. Among patients who received axi-cel, grade 3 or higher cytokine release syndrome occurred in 6% and grade 3 or higher neurologic events in 21%. No deaths related to cytokine release syndrome or neurologic events occurred. CONCLUSIONS: Axi-cel therapy led to significant improvements, as compared with standard care, in event-free survival and response, with the expected level of high-grade toxic effects. (Funded by Kite; ZUMA-7 ClinicalTrials.gov number, NCT03391466.).
Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Receptores de Antígenos Quiméricos/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/efeitos adversos , Produtos Biológicos/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Transplante de Células-Tronco , Transplante AutólogoRESUMO
BACKGROUND: Survival in Epstein-Barr virus (EBV)-positive post-transplant lymphoproliferative disease following haematopoietic stem-cell transplant (HSCT) or solid organ transplant (SOT) is poor after failure of initial therapy, indicating an urgent need for therapies for this ultra-rare disease. With recent EU marketing authorisation, tabelecleucel is the first off-the-shelf, allogeneic, EBV-specific T-cell immunotherapy to receive approval for treatment of relapsed or refractory EBV-positive post-transplant lymphoproliferative disease. We aimed to determine the clinical benefit of tabelecleucel in patients with relapsed or refractory EBV-positive post-transplant lymphoproliferative disease following HSCT or SOT. METHODS: In this global, multicentre, open-label, phase 3 trial, eligible patients (of any age) had biopsy-proven EBV-positive post-transplant lymphoproliferative disease, disease that was relapsed or refractory to rituximab after HSCT and rituximab with or without chemotherapy after SOT, and partially HLA-matched and appropriately HLA-restricted tabelecleucel available. Patients received tabelecleucel administered intravenously at 2 × 106 cells per kg on days 1, 8, and 15 in 35-day cycles and are assessed for up to 5 years for survival post-treatment initiation. The primary endpoint was objective response rate. All patients who received at least one dose of tabelecleucel were included in safety and efficacy analyses. This trial is registered with ClinicalTrials.gov, NCT03394365, and is ongoing. FINDINGS: From June 27, 2018, to Nov 5, 2021, 63 patients were enrolled, of whom 43 (24 [56%] male and 19 [44%] female) were included, 14 had prior HSCT, 29 had SOT. Seven (50%, 95% CI 23-77) of 14 participants in the HSCT group and 15 (52%, 33-71) of 29 participants in the SOT group had an objective response, with a median follow-up of 14·1 months (IQR 5·7-23·9) and 6·0 months (1·8-18·4), respectively. The most common grade 3 or 4 treatment-emergent adverse events were disease progression (in four [29%] of 14 in HSCT and eight [28%] of 29 in SOT) and decreased neutrophil count (in four [29%] of 14 in HSCT and four [14%] of 29 in SOT). Treatment-emergent serious adverse events were reported in 23 (53%) of 43 patients and fatal treatment-emergent adverse events in five (12%); no fatal treatment-emergent adverse event was treatment-related. There were no reports of tumour flare reaction, cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, transmission of infectious diseases, marrow rejection, or infusion reactions. No events of graft-versus-host disease or SOT rejection were reported as related to tabelecleucel. INTERPRETATION: Tabelecleucel provides clinical benefit in patients with relapsed or refractory EBV-positive post-transplant lymphoproliferative disease, for whom there are no other approved therapies, without evidence of safety concerns seen with other adoptive T-cell therapies. These data represent a potentially transformative and accessible treatment advance for patients with relapsed or refractory disease with few treatment options. FUNDING: Atara Biotherapeutics.
Assuntos
Infecções por Vírus Epstein-Barr , Transplante de Células-Tronco Hematopoéticas , Transtornos Linfoproliferativos , Transplante de Órgãos , Humanos , Masculino , Feminino , Rituximab/efeitos adversos , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/etiologia , Alelos , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/etiologia , Transplante de Órgãos/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversosRESUMO
This Good Practice Paper provides recommendations for the baseline investigation, risk stratification and use of prophylactic interventions for patients with large B-cell lymphoma at risk of central nervous system relapse. Recent evidence which has questioned the role of high-dose methotrexate in this clinical scenario is discussed in detail.
RESUMO
To optimise management of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection identifying high-risk patients and maintaining treatment dose intensity is an important issue in patients with aggressive lymphomas. In the present study, we report on the presentation, management, and outcome of an international series of 91 patients with primary central nervous system lymphoma and SARS-CoV-2 infection. SARS-CoV-2 was diagnosed before/during first-line treatment in 64 patients, during follow-up in 21, and during salvage therapy in six. Among the 64 patients infected before/during first-line chemotherapy, 38 (59%) developed pneumonia and 26 (41%) did not clear the virus. Prolonged exposure to steroids before viral infection and/or treatment with high-dose cytarabine favoured pneumonia development and virus persistence and were associated with poorer survival; 81% of patients who did not clear virus died early from coronavirus disease 2019 (COVID-19). Vaccination was associated with lower pneumonia incidence and in-hospital mortality. Chemotherapy was initiated/resumed in 43 (67%) patients, more commonly among patients who did not develop pneumonia, cleared the virus, or did not receive steroids during infection. Chemotherapy resumption in patients with viral persistence should be indicated cautiously as it was associated with a poorer survival (6-month, 70% and 87%, p = 0.07). None of the 21 patients infected during follow-up died from COVID-19, requiring similar measures as infected subjects in the general population.
Assuntos
COVID-19 , Linfoma , Humanos , SARS-CoV-2 , Sistema Nervoso Central , Linfoma/tratamento farmacológicoRESUMO
CD19 CAR-T have emerged as a new standard treatment for relapsed/refractory (r/r) large B-cell lymphoma (LBCL). CAR-T real-world (RW) outcomes published to date suggest significant variability across countries. We provide results of a large national cohort of patients intended to be treated with CAR-T in the UK. Consecutive patients with r/r LBCL approved for CAR-T by the National CAR-T Clinical Panel between December 2018 and November 2020 across all UK CAR-T centres were included. 404/432 patients were approved [292 axicabtagene ciloleucel (axi-cel), 112 tisagenlecleucel (tisa-cel)], 300 (74%) received the cells. 110/300 (38.3%) patients achieved complete remission (CR) at 6 months (m). The overall response rate was 77% (52% CR) for axi-cel, 57% (44% CR) for tisa-cel. The 12-month progression-free survival was 41.8% (axi-cel) and 27.4% (tisa-cel). Median overall survival for the intention-to-treat population was 10.5 m, 16.2 m for infused patients. The incidence of grade ≥3 cytokine release syndrome and neurotoxicity were 7.6%/19.6% for axi-cel and 7.9%/3.9% for tisa-cel. This prospective RW population of CAR-T eligible patients offers important insights into the clinical benefit of CD19 CAR-T in LBCL in daily practice. Our results confirm long-term efficacy in patients receiving treatment similar to the pivotal trials, but highlight the significance of early CAR-T failure.
Assuntos
Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Antígenos CD19/uso terapêutico , Síndrome da Liberação de Citocina , Humanos , Imunoterapia Adotiva/métodos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Estudos Prospectivos , Reino Unido/epidemiologiaRESUMO
The ubiquitous, early-stage expression, efficient internalization, limited off-target effects, and high disease specificity of CD19 make it an attractive therapeutic target. Currently available anti-CD19 therapies have demonstrated particular promise in patients with relapsed or refractory B-cell non-Hodgkin lymphoma. Selection of the most appropriate treatment strategy should be based on individual patient characteristics and the goal of therapy. However, evidence and knowledge about the sequencing of anti-CD19 therapies are limited. Here, we review the current evidence for CD19 as a target in diffuse large B-cell lymphoma and consider approaches to the use of anti-CD19 therapy.
Assuntos
Prova Pericial , Linfoma Difuso de Grandes Células B , Antígenos CD19/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológicoAssuntos
Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Humanos , Linfoma Difuso de Grandes Células B/terapia , Linfoma Difuso de Grandes Células B/imunologia , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/efeitos adversos , Receptores de Antígenos Quiméricos/imunologia , Resultado do Tratamento , Masculino , FemininoRESUMO
BACKGROUND: Mobilized peripheral blood stem cells are currently the predominant source of grafts for allogeneic transplantation (allogeneic peripheral blood stem cell transplantation [allo-PBSCT]), although, in comparison with bone marrow, their use is associated with an increased risk of chronic graft-versus-host disease (cGVHD). Attempts to reduce the incidence of cGVHD include the addition of anti-thymocyte globulin (ATG) to the pretransplant conditioning regimen. METHODS: The goal of this retrospective study was to analyze the effect of ATG on allo-PBSCT outcomes for adults with Philadelphia-negative acute lymphoblastic leukemia (Ph-neg ALL). The primary endpoint was survival free from relapse, grade 3 to 4 acute graft-versus-host disease (aGVHD), and cGVHD (ie, graft-versus-host disease-free/relapse-free survival [GRFS]). Nine-hundred twenty-four patients who underwent unmanipulated allo-PBSCT in their first complete remission between 2007 and 2016 were included. ATG was used in 97 of the 494 transplants from matched sibling donors (20%) and in 307 of the 430 transplants from human leukocyte antigen-matched (8 of 8 loci) unrelated donors (71%). RESULTS: The use of ATG was an independent factor for an improved chance of GRFS (hazard ratio [HR], 0.70; P = .0009). Furthermore, it was associated with a reduced risk of both grade 2 to 4 (HR, 0.66; P = .005) and grade 3 to 4 aGVHD (HR, 0.58; P = .03). Similarly, its addition reduced the incidence of both total (HR, 0.45; P < 10-5 ) and extensive cGVHD (HR, 0.30; P < 10-5 ) as well as nonrelapse mortality (HR, 0.58; P = .01). No significant effect was found with respect to leukemia-free or overall survival. However, an increased risk of relapse was noted for those who received ATG (HR, 1.40; P = .04). CONCLUSIONS: Patients with Ph-neg ALL treated with allo-PBSCT benefit from the use of ATG in terms of improved GRFS. Its use may, therefore, be considered in this setting. Cancer 2018;124:2523-33. © 2018 American Cancer Society.
Assuntos
Soro Antilinfocitário/administração & dosagem , Doença Enxerto-Hospedeiro/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/imunologia , Transplante de Células-Tronco de Sangue Periférico/métodos , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Sistema de Registros/estatística & dados numéricos , Indução de Remissão , Estudos Retrospectivos , Análise de Sobrevida , Transplante Homólogo/efeitos adversos , Transplante Homólogo/métodos , Adulto JovemAssuntos
Neoplasias do Sistema Nervoso Central , Linfoma , Humanos , Recidiva Local de Neoplasia , Linfoma/terapia , Linfoma/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/terapia , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Sistema Nervoso Central/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoAssuntos
Neoplasias do Sistema Nervoso Central , Transplante de Células-Tronco Hematopoéticas , Linfoma , Humanos , Tiotepa/uso terapêutico , Transplante Autólogo , Linfoma/patologia , Sistema Nervoso Central/patologia , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Transplante de Células-TroncoRESUMO
Allogeneic hematopoietic cell transplantation (alloHCT) with myeloablative conditioning based on total body irradiation (TBI) is widely used for the treatment of adults with acute lymphoblastic leukemia (ALL). TBI is most frequently administered in combination with either cyclophosphamide (Cy/TBI) or etoposide (Vp/TBI). The goal of this study was to retrospectively compare these two regimens. Adult patients with Ph-negative ALL treated with alloHCT in first or second complete remission who received Cy/TBI (n = 1346) or Vp/TBI (n = 152) conditioning were included in the analysis. In a univariate analysis, as compared to Cy/TBI, the use of Vp/TBI was associated with reduced incidence of relapse (17% vs. 30% at 5 years, P = .007), increased rate of leukemia-free survival (60% vs. 50%, P = .04), and improved "graft versus host disease (GVHD) and relapse-free survival" (GRFS, 43% vs. 33%, P = .04). No significant effect could be observed in terms of the incidence of nonrelapse mortality or acute or chronic GVHD. In a multivariate model, the use of Vp/TBI was associated with reduced risk of relapse (HR = 0.62, P = .04) while the effect on other study end-points was not significant. In conclusion, conditioning regimen based on Vp combined with TBI appears more effective for disease control than the combination of Cy with TBI for adult patients with Ph-negative ALL treated with alloHCT.
Assuntos
Ciclofosfamida/uso terapêutico , Etoposídeo/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Condicionamento Pré-Transplante/métodos , Irradiação Corporal Total/métodos , Adulto , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Transplante HomólogoRESUMO
Allogeneic stem cell transplantation (allo-HSCT) provides a unique opportunity to track Epstein-Barr virus (EBV) infection in the context of the reconstituting B-cell system. Although many allo-HSCT recipients maintain low or undetectable levels of EBV DNA posttransplant, a significant proportion exhibit elevated and rapidly increasing EBV loads which, if left untreated, may lead to potentially fatal EBV-associated posttransplant lymphoproliferative disease. Intriguingly, this high-level EBV reactivation typically arises in the first 3 months posttransplant, at a time when the peripheral blood contains low numbers of CD27+ memory cells which are the site of EBV persistence in healthy immunocompetent donors. To investigate this apparent paradox, we prospectively monitored EBV levels and B-cell reconstitution in a cohort of allo-HSCT patients for up to 12 months posttransplant. In patients with low or undetectable levels of EBV, the circulating B-cell pool consisted predominantly of transitional and naive cells, with a marked deficiency of CD27+ memory cells which lasted >12 months. However, among patients with high EBV loads, there was a significant increase in both the proportion and number of CD27+ memory B cells. Analysis of sorted CD27+ memory B cells from these patients revealed that this population was preferentially infected with EBV, expressed EBV latent transcripts associated with B-cell growth transformation, had a plasmablastic phenotype, and frequently expressed the proliferation marker Ki-67. These findings suggest that high-level EBV reactivation following allo-HSCT may drive the expansion of latently infected CD27+ B lymphoblasts in the peripheral blood.
Assuntos
Linfócitos B/virologia , Transformação Celular Viral/fisiologia , Infecções por Vírus Epstein-Barr/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4/fisiologia , Ativação Viral/imunologia , Adulto , Idoso , Subpopulações de Linfócitos B/virologia , DNA Viral/sangue , Feminino , Humanos , Memória Imunológica/imunologia , Transtornos Linfoproliferativos/virologia , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Carga Viral/imunologiaAssuntos
Transplante de Células-Tronco Hematopoéticas , Linfoma de Células T/terapia , Gerenciamento Clínico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Linfoma de Células T/diagnóstico , Transplante Autólogo , Transplante Homólogo , Resultado do TratamentoRESUMO
Epstein-Barr virus (EBV), a lymphomagenic human herpesvirus, colonises the host through polyclonal B cell-growth-transforming infections yet establishes persistence only in IgD⺠CD27⺠non-switched memory (NSM) and IgDâ» CD27⺠switched memory (SM) B cells, not in IgD⺠CD27â» naïve (N) cells. How this selectivity is achieved remains poorly understood. Here we show that purified N, NSM and SM cell preparations are equally transformable in vitro to lymphoblastoid cells lines (LCLs) that, despite upregulating the activation-induced cytidine deaminase (AID) enzyme necessary for Ig isotype switching and Ig gene hypermutation, still retain the surface Ig phenotype of their parental cells. However, both N- and NSM-derived lines remain inducible to Ig isotype switching by surrogate T cell signals. More importantly, IgH gene analysis of N cell infections revealed two features quite distinct from parallel mitogen-activated cultures. Firstly, following 4 weeks of EBV-driven polyclonal proliferation, individual clonotypes then become increasingly dominant; secondly, in around 35% cases these clonotypes carry Ig gene mutations which both resemble AID products and, when analysed in prospectively-harvested cultures, appear to have arisen by sequence diversification in vitro. Thus EBV infection per se can drive at least some naïve B cells to acquire Ig memory genotypes; furthermore, such cells are often favoured during an LCL's evolution to monoclonality. Extrapolating to viral infections in vivo, these findings could help to explain how EBV-infected cells become restricted to memory B cell subsets and why EBV-driven lymphoproliferative lesions, in primary infection and/or immunocompromised settings, so frequently involve clones with memory genotypes.