Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Br J Haematol ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566733

RESUMO

Viral respiratory infections (VRIs) contribute to the morbidity and transplant-related mortality (TRM) after allogeneic haematopoietic stem cell transplantation (HSCT) and strategies to prevent and treat VRIs are warranted. We monitored VRIs before and after transplant in children undergoing allogeneic HSCT with nasopharyngeal aspirates (NPA) and assessed the impact on clinical outcome. Between 2007 and 2017, 585 children underwent 620 allogeneic HSCT procedures. Out of 75 patients with a positive NPA screen (12%), transplant was delayed in 25 cases (33%), while 53 children started conditioning with a VRI. Patients undergoing HSCT with a positive NPA screen had a significantly lower overall survival (54% vs. 79%) and increased TRM (26% vs. 7%) compared to patients with a negative NPA. Patients with a positive NPA who delayed transplant and cleared the virus before conditioning had improved overall survival (90%) and lower TRM (5%). Pre-HSCT positive NPA was the only significant risk factor for progression to a lower respiratory tract infection and was a major risk factor for TRM. Transplant delay, whenever feasible, in case of a positive NPA screen for VRIs can positively impact on survival of children undergoing HSCT.

2.
Nat Med ; 25(9): 1408-1414, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31477906

RESUMO

Chimeric antigen receptor (CAR)-modified T cells targeting CD19 demonstrate unparalleled responses in relapsed/refractory acute lymphoblastic leukemia (ALL)1-5, but toxicity, including cytokine-release syndrome (CRS) and neurotoxicity, limits broader application. Moreover, 40-60% of patients relapse owing to poor CAR T cell persistence or emergence of CD19- clones. Some factors, including the choice of single-chain spacer6 and extracellular7 and costimulatory domains8, have a profound effect on CAR T cell function and persistence. However, little is known about the impact of CAR binding affinity. There is evidence of a ceiling above which increased immunoreceptor affinity may adversely affect T cell responses9-11. We generated a novel CD19 CAR (CAT) with a lower affinity than FMC63, the high-affinity binder used in many clinical studies1-4. CAT CAR T cells showed increased proliferation and cytotoxicity in vitro and had enhanced proliferative and in vivo antitumor activity compared with FMC63 CAR T cells. In a clinical study (CARPALL, NCT02443831 ), 12/14 patients with relapsed/refractory pediatric B cell acute lymphoblastic leukemia treated with CAT CAR T cells achieved molecular remission. Persistence was demonstrated in 11 of 14 patients at last follow-up, with enhanced CAR T cell expansion compared with published data. Toxicity was low, with no severe CRS. One-year overall and event-free survival were 63% and 46%, respectively.

3.
Blood Adv ; 2(7): 777-786, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29618462

RESUMO

Patients with juvenile idiopathic arthritis (JIA) can experience a severe disease course, with progressive destructive polyarthritis refractory to conventional therapy with disease-modifying antirheumatic drugs including biologics, as well as life-threatening complications including macrophage activation syndrome (MAS). Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative immunomodulatory strategy for patients with such refractory disease. We treated 16 patients in 5 transplant centers between 2007 and 2016: 11 children with systemic JIA and 5 with rheumatoid factor-negative polyarticular JIA; all were either refractory to standard therapy, had developed secondary hemophagocytic lymphohistiocytosis/MAS poorly responsive to treatment, or had failed autologous HSCT. All children received reduced toxicity fludarabine-based conditioning regimens and serotherapy with alemtuzumab. Fourteen of 16 patients are alive with a median follow-up of 29 months (range, 2.8-96 months). All patients had hematological recovery. Three patients had grade II-IV acute graft-versus-host disease. The incidence of viral infections after HSCT was high, likely due to the use of alemtuzumab in already heavily immunosuppressed patients. All patients had significant improvement of arthritis, resolution of MAS, and improved quality of life early following allo-HSCT; most importantly, 11 children achieved complete drug-free remission at the last follow-up. Allo-HSCT using alemtuzumab and reduced toxicity conditioning is a promising therapeutic option for patients with JIA refractory to conventional therapy and/or complicated by MAS. Long-term follow-up is required to ascertain whether disease control following HSCT continues indefinitely.

4.
Blood Adv ; 1(24): 2206-2216, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29296868

RESUMO

Omission of in vivo T-cell depletion promotes rapid, thymic-independent CD4+-biased T-cell recovery after cord blood transplant. This enhanced T-cell reconstitution differs from that seen after stem cell transplant from other stem cell sources, but the mechanism is not known. Here, we demonstrate that the transcription profile of naive CD4+ T cells from cord blood and that of lymphocytes reconstituting after cord blood transplantation is similar to the transcription profile of fetal CD4+ T cells. This profile is distinct to that of naive CD4+ T cells from peripheral blood and that of lymphocytes reconstituting after T-replete bone marrow transplantation. The transcription profile of reconstituting naive CD4+ T cells from cord blood transplant recipients was upregulated in the T-cell receptor (TCR) signaling pathway and its transcription factor activator protein-1 (AP-1). Furthermore, a small molecule inhibitor of AP-1 proportionally inhibited cord blood CD4+ T-cell proliferation (P < .05). Together, these findings suggest that reconstituting cord blood CD4+ T cells reflect the properties of fetal ontogenesis, and enhanced TCR signaling is responsible for the rapid restoration of the unique CD4+ T-cell biased adaptive immunity after cord blood transplantation.

5.
Br J Haematol ; 171(4): 585-94, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26223288

RESUMO

We explored the feasibility of unrelated donor haematopoietic stem cell transplant (HSCT) upfront without prior immunosuppressive therapy (IST) in paediatric idiopathic severe aplastic anaemia (SAA). This cohort was then compared to matched historical controls who had undergone first-line therapy with a matched sibling/family donor (MSD) HSCT (n = 87) or IST with horse antithymocyte globulin and ciclosporin (n = 58) or second-line therapy with unrelated donor HSCT post-failed IST (n = 24). The 2-year overall survival in the upfront cohort was 96 ± 4% compared to 91 ± 3% in the MSD controls (P = 0·30) and 94 ± 3% in the IST controls (P = 0·68) and 74 ± 9% in the unrelated donor HSCT post-IST failure controls (P = 0·02).The 2-year event-free survival in the upfront cohort was 92 ± 5% compared to 87 ± 4% in MSD controls (P = 0·37), 40 ± 7% in IST controls (P = 0·0001) and 74 ± 9% in the unrelated donor HSCT post-IST failure controls (n = 24) (P = 0·02). Outcomes for upfront-unrelated donor HSCT in paediatric idiopathic SAA were similar to MSD HSCT and superior to IST and unrelated donor HSCT post-IST failure. Front-line therapy with matched unrelated donor HSCT is a novel treatment approach and could be considered as first-line therapy in selected paediatric patients who lack a MSD.


Assuntos
Anemia Aplástica/terapia , Transplante de Medula Óssea/estatística & dados numéricos , Transplante de Células-Tronco de Sangue Periférico/estatística & dados numéricos , Infecções por Adenoviridae/tratamento farmacológico , Infecções por Adenoviridae/epidemiologia , Adolescente , Adulto , Anemia Aplástica/mortalidade , Soro Antilinfocitário , Transfusão de Sangue/estatística & dados numéricos , Transplante de Medula Óssea/efeitos adversos , Estudos de Casos e Controles , Criança , Pré-Escolar , Ciclosporina/uso terapêutico , Intervalo Livre de Doença , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/epidemiologia , Histocompatibilidade , Humanos , Imunossupressores/uso terapêutico , Lactente , Estimativa de Kaplan-Meier , Tempo de Internação/estatística & dados numéricos , Doadores Vivos , Masculino , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/epidemiologia , Disfunção Primária do Enxerto/epidemiologia , Qualidade de Vida , Estudos Retrospectivos , Irmãos , Taxa de Sobrevida , Linfócitos T , Resultado do Tratamento , Ativação Viral , Adulto Jovem
7.
Blood ; 124(16): 2514-22, 2014 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-25185261

RESUMO

Epstein-Barr virus (EBV)-associated posttransplant lymphoma (PTLD) is a major cause of morbidity/mortality after hematopoietic stem cell (SCT) or solid organ (SOT) transplant. Adoptive immunotherapy with EBV-specific cytotoxic lymphocytes (CTLs), although effective in SCT, is less successful after SOT where lifelong immunosuppression therapy is necessary. We have genetically engineered EBV-CTLs to render them resistant to calcineurin (CN) inhibitor FK506 through retroviral transfer of a calcineurin A mutant (CNA12). Here we examined whether or not FK506-resistant EBV-CTLs control EBV-driven tumor progression in the presence of immunosuppression in a xenogeneic mouse model. NOD/SCID/IL2rγ(null) mice bearing human B-cell lymphoma were injected with autologous CTLs transduced with either CNA12 or eGFP in the presence/absence of FK506. Adoptive transfer of autologous CNA12-CTLs induced dramatic lymphoma regression despite the presence of FK506, whereas eGFP-CTLs did not. CNA12-CTLs persisted longer, homed to the tumor, and expanded more than eGFP-CTLs in mice treated with FK506. Mice receiving CNA12-CTLs and treated with FK506 survived significantly longer than control-treated animals. Our results demonstrate that CNA12-CTL induce regression of EBV-associated tumors in vivo despite ongoing immunosuppression. Clinical application of this novel approach may enhance the efficacy of adoptive transfer of EBV-CTL in SOT patients developing PTLD without the need for reduction in immunosuppressive therapy.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Terapia Genética , Imunoterapia Adotiva , Linfoma/terapia , Linfoma/virologia , Linfócitos T Citotóxicos/transplante , Linfócitos T Citotóxicos/virologia , Animais , Calcineurina/genética , Inibidores de Calcineurina/farmacologia , Resistência a Medicamentos , Engenharia Genética/métodos , Terapia Genética/métodos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Imunossupressores/farmacologia , Imunoterapia Adotiva/métodos , Linfoma/genética , Linfoma/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/metabolismo , Tacrolimo/farmacologia , Transdução Genética
8.
Blood ; 123(1): 126-32, 2014 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-24184682

RESUMO

In vivo T-cell depletion might contribute to the delayed immune reconstitution observed after unrelated umbilical cord blood transplantation (UCBT). We studied the impact of early, late, and no antithymocyte globulin (ATG) on immune reconstitution and outcome. One hundred twenty seven children receiving UCBT in London or Utrecht were divided into 3 groups: early ATG (days -9 to -5; n = 33), late ATG (days -5 to 0; n = 48), and no ATG (n = 46). The no-ATG group received mycophenolate mofetile + cyclosporin A as graft-versus-host disease (GVHD) prophylaxis, while the ATG groups received cyclosporin A + prednisone. End points studied were survival, immune recovery, infections, and GVHD. The probability of survival was similar in all groups: no ATG, 71% ± 8%; early ATG, 68% ± 9%; and late ATG, 61% ± 7%. CD3(+), CD4(+), and CD4(+)-naive T-cell counts were significantly higher (P < .001) in the no-ATG group at 1, 2, 3, 6, and 12 months post-UCBT. In the no-ATG group, significantly fewer viral reactivations (P = .021) were noted. A higher probability of severe acute GVHD (aGVHD; 31%) was found in the no-ATG group compared with 18% (P = .018) for early-ATG and 5% (P < .001) for late-ATG groups. This was not associated with more chronic GVHD (cGVHD).


Assuntos
Soro Antilinfocitário/metabolismo , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Sangue Fetal/citologia , Adolescente , Soro Antilinfocitário/uso terapêutico , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/imunologia , Humanos , Imunossupressores/uso terapêutico , Lactente , Masculino , Probabilidade , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento , Adulto Jovem
9.
Clin Immunol ; 149(3): 464-74, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24230999

RESUMO

Defective V(D)J recombination and DNA double-strand break (DSB) repair severely impair the development of T-lymphocytes and B-lymphocytes. Most patients manifest a severe combined immunodeficiency during infancy. We report 2 siblings with combined immunodeficiency (CID) and immunodysregulation caused by compound heterozygous Artemis mutations, including an exon 1-3 deletion generating a null allele, and a missense change (p.T71P). Skin fibroblasts demonstrated normal DSB repair by gamma-H2AX analysis, supporting the predicted hypomorphic nature of the p.T71P allele. In addition to these two patients, 12 patients with Artemis-deficient CID were previously reported. All had significant morbidities including recurrent infections, autoimmunity, EBV-associated lymphoma, and carcinoma despite having hypomorphic mutants with residual Artemis expression, V(D)J recombination or DSB repair capacity. Nine patients underwent stem cell transplant and six survived, while four patients who did not receive transplant died. The progressive nature of immunodeficiency and genomic instability accounts for poor survival, and early HSCT should be considered.


Assuntos
Estudos de Associação Genética , Mutação , Proteínas Nucleares/genética , Imunodeficiência Combinada Severa/genética , Adulto , Sequência de Aminoácidos , Pré-Escolar , Endonucleases , Feminino , Heterogeneidade Genética , Instabilidade Genômica , Heterozigoto , Humanos , Lactente , Dados de Sequência Molecular , Proteínas Nucleares/imunologia , Imunodeficiência Combinada Severa/imunologia , Imunodeficiência Combinada Severa/patologia , Irmãos , Recombinação V(D)J/imunologia
10.
Blood ; 122(23): 3749-58, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24113871

RESUMO

Severe combined immunodeficiency (SCID) arises from different genetic defects associated with lymphocyte development and function and presents with severe infections. Allogeneic hematopoietic stem cell transplantation is an extremely effective way of restoring immunity in these individuals. Numerous multicenter studies have identified the factors determining successful outcome, and survival for SCID has shown great improvement. Advances in understanding the genetic basis of disease also mean that we increasingly tailor transplant protocols to the specific SCID form. Wherever possible, we attempt to transplant SCID patients without the use of cytoreductive conditioning, but it is clear that this is only successful for specific SCID forms and, although survival is good, in specific patients there are ongoing humoral defects. We aim to use matched related and unrelated donors (including cord blood) whenever possible and have limited the use of mismatched haploidentical donors. The development of autologous hematopoietic stem cell gene therapy provides another treatment of the X-linked and adenosine deaminase-deficient forms of SCID, and we discuss how we have integrated gene therapy into our treatment strategy. These developments together with the advent of universal newborn screening for SCID should allow for a highly favorable outcome for this otherwise lethal condition.


Assuntos
Imunodeficiência Combinada Severa/terapia , Adenosina Desaminase/uso terapêutico , Pré-Escolar , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Terapia Genética , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Recém-Nascido , Masculino , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Doadores de Tecidos , Condicionamento Pré-Transplante
12.
Pediatr Nephrol ; 28(10): 2053-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23743853

RESUMO

BACKGROUND: Primary central nervous system (PCNS) post-transplant lymphoproliferative disorder (PTLD) is a rare complication of solid organ transplantation and is typically an Epstein-Barr virus (EBV)-induced B-cell CD20+ lymphoma. The modalities of treatment include reduction in immunosuppression, cranial radiotherapy (CRT), intravenous and intrathecal rituximab when CD20 is expressed on B-lymphocytes and PTLD cells, and chemotherapy. CASE-DIAGNOSIS/TREATMENT: We report the successful treatment of EBV-driven PCNS PTLD by reduction in immunosuppression (RI), CRT, and intravenous rituximab. Our patient was an 11-year-old boy with a living-related renal transplant for end-stage renal failure (ESRF) secondary to posterior urethral valves (PUV) and bilateral renal dysplasia (BRD) and on triple immunosuppression with prednisolone, tacrolimus, and azathioprine who had a rising EBV load, which was managed with reduction in tacrolimus dose, withdrawal of azathioprine, and introduction of mycophenolate mofetil (MMF). CONCLUSIONS: The patient presented 7 years post-transplant with a seizure and abnormal neurology secondary to polymorphous hyperplastic lesions in the brain, which responded to rituximab and CRT.


Assuntos
Anticorpos Monoclonais Murinos/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias do Sistema Nervoso Central/terapia , Quimiorradioterapia , Irradiação Craniana , Infecções por Vírus Epstein-Barr/virologia , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Linfoma de Células B/terapia , Antígenos CD20/metabolismo , Biópsia , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/imunologia , Neoplasias do Sistema Nervoso Central/virologia , Criança , Quimioterapia Combinada , Infecções por Vírus Epstein-Barr/diagnóstico , Humanos , Imuno-Histoquímica , Imunossupressores/efeitos adversos , Infusões Intravenosas , Linfoma de Células B/diagnóstico , Linfoma de Células B/imunologia , Linfoma de Células B/virologia , Imagem por Ressonância Magnética , Masculino , Rituximab , Convulsões/virologia , Fatores de Tempo , Resultado do Tratamento
13.
Blood ; 121(6): 877-83, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23131490

RESUMO

There have been no studies on patient outcome after allogeneic hematopoietic cell transplantation (HCT) in patients with X-linked inhibitor of apoptosis (XIAP) deficiency. To estimate the success of HCT, we conducted an international survey of transplantation outcomes. Data were reported for 19 patients. Seven patients received busulfan-containing myeloablative conditioning (MAC) regimens. Eleven patients underwent reduced intensity conditioning (RIC) regimens predominantly consisting of alemtuzumab, fludarabine, and melphalan. One patient received an intermediate-intensity regimen. Survival was poor in the MAC group, with only 1 patient surviving (14%). Most deaths were from transplantation-related toxicities, including venoocclusive disease and pulmonary hemorrhage. Of the 11 patients who received RIC, 6 are currently surviving at a median of 570 days after HCT (55%). Preparative regimen and HLH activity affected outcomes, and of RIC patients reported to be in remission from HLH, survival is 86% (P = .03). We conclude that MAC regimens should not be used for patients with XIAP deficiency. It is possible that the loss of XIAP and its antiapoptotic functions contributes to the high incidence of toxicities observed with MAC regimens. RIC regimens should be pursued with caution and, if possible, efforts should be made to ensure HLH remission before HCT in these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Transtornos Linfoproliferativos/terapia , Condicionamento Pré-Transplante/métodos , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Europa (Continente) , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/mortalidade , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hemorragia/etiologia , Hepatopatia Veno-Oclusiva/etiologia , Humanos , Lactente , Japão , Pulmão/irrigação sanguínea , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/mortalidade , Mutação , Avaliação de Resultados (Cuidados de Saúde)/estatística & dados numéricos , Indução de Remissão , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida , Transplante Homólogo , Estados Unidos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Adulto Jovem
14.
Cytotherapy ; 15(1): 109-21, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23260091

RESUMO

BACKGROUND AIMS: Immunotherapy with allodepleted donor T cells improves immunity after T cell-depleted hematopoietic stem cell transplantation. We developed a methodology for selective depletion of alloreactive T cells after activation with host antigen-presenting cells by targeting T cells up-regulating CD25 and CD71. Combined depletion of these cells yields a pool of allodepleted donor T cells with antiviral properties with minimal capacity to cause graft-versus-host disease. METHODS: Mature dendritic cells were irradiated and used to stimulate donor peripheral blood mononuclear cells for 4 days. The co-culture was stained with anti-CD71-biotin followed by CliniMACS CD25 and Anti-Biotin Reagents (Miltenyi Biotec GmbH; Bergisch Gladbach, Germany) before depletion on the CliniMACS Plus (Miltenyi Biotec GmbH). Residual alloreactivity was tested by flow cytometry, a secondary mixed lymphocyte reaction and limiting dilution analysis, and specific anti-viral immunity with pentamer staining. The large-scale protocol was tested under current good manufacturing practice conditions in five donor-recipient pairs of human leukocyte antigen-matched volunteer donors. RESULTS: We developed a closed-system methodology using cell differentiation bags for cell culture and the COBE2991 Cell Processor (CaridianBCT, Lakewood, CO, USA). We also validated an anti-CD71-biotin generated for ex vivo clinical use. In five large-scale runs, the depleted fraction demonstrated excellent viability (99.9%), minimal residual expression of CD3/CD25 and CD3/CD71 (<0.2%) and passed tests for Mycoplasma, endotoxin, bacterial and fungal sterility. In secondary mixed lymphocyte reaction assays, the median response to host after allodepletion was 0%, whereas responses to third-party peripheral blood mononuclear cells were preserved (median, 105%; range 37%-350%). Limiting dilution analysis assays also demonstrated a reduction in response to host (median, -1.11 log) with preservation of third-party responses, and testing with human leukocyte antigen-restricted pentamers showed that populations of Epstein-Barr virus-specific and cytomegalovirus-specific CD8(+) T cells were retained after depletion. CONCLUSIONS: We optimized a protocol for the combined immunomagnetic depletion of alloreactive CD25/CD71 T cells under current good manufacturing practice conditions and tested the efficacy in five donor-recipient pairs.


Assuntos
Antígenos CD/metabolismo , Técnicas de Cultura de Células/métodos , Células Dendríticas/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Depleção Linfocítica , Receptores da Transferrina/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Células Cultivadas , Técnicas de Cocultura , Citometria de Fluxo , Doença Enxerto-Hospedeiro/imunologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Leucócitos Mononucleares/imunologia
15.
Br J Haematol ; 156(5): 656-66, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22224700

RESUMO

Umbilical cord blood transplant (UCBT) is associated with impaired early immune reconstitution. This might be explained by a lower T-cell dose infused, the naivety of cord blood T-cells and the use of in vivo T-cell depletion. We studied the pattern of early immune reconstitution and the clinical outcome of children undergoing unrelated UCBT when in vivo T-cell depletion was omitted. Thirty children affected by malignancies (46%) or immunodeficiencies (54%) underwent an unrelated UCBT. Prospective assessment of immune reconstitution and clinical outcome was performed. We observed an unprecedented CD4(+) T-cell reconstitution, with a median cell count at 30 and 60 d post UCBT of 0.3 × 10(9) /l and 0.56 × 10(9) /l, respectively. Early T-cell expansion was thymic-independent, with a rapid shift from naïve to central memory phenotype and early regulatory T-cell recovery. Viral infections were frequent (63%) but resolved rapidly in most cases and virus-specific T-lymphocytes were detected within 2 months post-UCBT. Acute graft-versus-host disease (GvHD) was frequent (grade II = 34%, grade III-IV = 16%) but steroid responsive, and the incidence of chronic GvHD was low (14%). The omission of in vivo T-cell depletion promotes a unique thymic-independent CD4(+) T-cell reconstitution after unrelated UCBT in children. We postulate that this relates to the specific immunological and ontological qualities of fetal-derived lymphocytes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Imunidade Adaptativa , Linfócitos B/imunologia , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Memória Imunológica , Imunofenotipagem , Lactente , Células Matadoras Naturais/imunologia , Contagem de Linfócitos , Depleção Linfocítica , Masculino , Infecções Oportunistas/imunologia , Infecções Oportunistas/prevenção & controle , Linfócitos T Reguladores/imunologia , Resultado do Tratamento
16.
J Immunother ; 35(1): 42-53, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22130159

RESUMO

Previous studies have established that adoptive immunotherapy with donor-derived virus-specific T cells can prevent/treat viral complications post-stem cell transplant and regulatory T cells show promise as inhibitors of graft-versus-host disease. On the basis of flow cytometric analysis of upregulation of activation markers after stimulation with viral peptide pools, we have developed a rapid and clinically applicable protocol for the simultaneous selection of virus-specific T cells (after stimulation with peptide pools for the immunodominant antigens of cytomegalovirus, Epstein-Barr virus, and adenovirus) and regulatory T cells using CD25 immunomagnetic selection. Using tetramer staining, we detected enrichment of CD8 T cells recognizing peptide epitopes from cytomegalovirus and Epstein-Barr virus antigens after CD25 selection in 6 of 7 donors. Enzyme-linked immunospot assays demonstrated the simultaneous presence of bivirus-specific or trivirus-specific cells in all evaluated donors, with a median 29-fold (6 to 168), 40-fold (1 to 247), and 16-fold (1 to 219) enrichment of cells secreting interferon-γ in response to cytomegalovirus pp65, adenovirus hexon, and Epstein-Barr virus lymphoblastoid cells compared with unmanipulated peripheral blood mononuclear cells from the same donors. Furthermore, the CD25-enriched cells lost alloreactivity in H-thymidine proliferation assays and showed highly effective (median, 98%) suppression of alloreactivity in all evaluated donors. In summary, we have developed a rapid, simple Good Manufacturing Practice compliant methodology for the simultaneous selection of T cells with multiple viral specificities and regulatory T cells. Adoptive transfer of T cells generated using this strategy may enable restoration of cellular immunity to viruses after allogeneic stem cell transplant with a low risk of graft-versus-host disease. Owing to the speed and simplicity of this methodology, this approach may significantly broaden the applicability of adoptive immunotherapy.


Assuntos
Adenoviridae/imunologia , Linfócitos T CD8-Positivos/imunologia , Separação Celular/métodos , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Herpesvirus Humano 4/imunologia , Imunoterapia Adotiva/métodos , Linfócitos T Reguladores/metabolismo , Linfócitos T CD8-Positivos/patologia , Proteínas do Capsídeo/imunologia , Proliferação de Células , Células Cultivadas , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/terapia , Citotoxicidade Imunológica , Humanos , Imunossupressão , Interferon gama/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Teste de Cultura Mista de Linfócitos , Fosfoproteínas/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Proteínas da Matriz Viral/imunologia
17.
Br J Haematol ; 155(3): 377-85, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21910716

RESUMO

This study investigated the efficacy of a pre-emptive strategy based on the combination of Epstein-Barr virus (EBV) viraemia and poor T cell reconstitution in preventing post-transplant lymphoproliferative disease (PTLD) following T cell depleted stem cell transplant (SCT). EBV viral load and immune reconstitution were prospectively monitored in 70 consecutive children undergoing SCT following reduced intensity conditioning with alemtuzumab. Patients who developed significant EBV viraemia (> 40 000 copies/ml blood) were treated pre-emptively with rituximab if they were within 3 months of SCT or their CD3 count was <0·3 × 109 /l. Of 20/70 patients who developed significant EBV viraemia, 13 received pre-emptive rituximab. The incidence of PTLD was significantly reduced in the pre-emptive cohort compared to historical controls (1·4% vs. 21·7%, P = 0·003). This difference was more marked among viraemic patients (2·7% vs. 62·5%P < 0·0001). Patients treated with rituximab demonstrated significantly delayed B cell reconstitution at 1 year post-SCT but this was not associated with an increase in infectious mortality. In 6/6 patients >3 months post-SCT who had a CD3 count >0·3 × 109 /l, reduced immunosuppression only resulted in successful resolution of EBV viraemia without PTLD. This strategy is safe and highly effective in preventing PTLD following T cell depleted SCT, and directs rituximab therapy to patients at highest risk of this complication.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Infecções por Vírus Epstein-Barr/prevenção & controle , Herpesvirus Humano 4/fisiologia , Transtornos Linfoproliferativos/prevenção & controle , Transplante de Células-Tronco/métodos , Linfócitos T/imunologia , Adolescente , Adulto , Alemtuzumab , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Antineoplásicos/administração & dosagem , Criança , Pré-Escolar , Estudos de Coortes , Infecções por Vírus Epstein-Barr/etiologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Humanos , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/virologia , Masculino , Estudos Prospectivos , Rituximab , Transplante de Células-Tronco/efeitos adversos , Linfócitos T/efeitos dos fármacos , Viremia/etiologia , Viremia/imunologia , Viremia/prevenção & controle , Viremia/virologia , Ativação Viral , Adulto Jovem
18.
J Allergy Clin Immunol ; 126(3): 602-10.e1-11, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20673987

RESUMO

BACKGROUND: Hematopoietic stem cell transplantation remains the only treatment for most patients with severe combined immunodeficiencies (SCIDs) or other primary immunodeficiencies (non-SCID PIDs). OBJECTIVE: To analyze the long-term outcome of patients with SCID and non-SCID PID from European centers treated between 1968 and 2005. METHODS: The product-limit method estimated cumulative survival; the log-rank test compared survival between groups. A Cox proportional-hazard model evaluated the impact of independent predictors on patient survival. RESULTS: In patients with SCID, survival with genoidentical donors (n = 25) from 2000 to 2005 was 90%. Survival using a mismatched relative (n = 96) has improved (66%), similar to that using an unrelated donor (n = 46; 69%; P = .005). Transplantation after year 1995, a younger age, B(+) phenotype, genoidentical and phenoidentical donors, absence of respiratory impairment, or viral infection before transplantation were associated with better prognosis on multivariate analysis. For non-SCID PID, in contrast with patients with SCID, we confirm that, in the 2000 to 2005 period, using an unrelated donor (n = 124) gave a 3-year survival rate similar to a genoidentical donor (n = 73), 79% for both. Survival was 76% in phenoidentical transplants (n = 23) and worse in mismatched related donor transplants (n = 47; 46%; P = .016). CONCLUSION: This is the largest cohort study of such patients with the longest follow-up. Specific issues arise for different patient groups. Patients with B-SCID have worse survival than other patients with SCID, despite improvements in each group. For non-SCID PID, survival is worse than SCID, although more conditions are now treated. Individual disease categories now need to be analyzed so that disease-specific prognosis may be better understood and the best treatments planned.


Assuntos
Transplante de Células-Tronco Hematopoéticas/normas , Imunodeficiência Combinada Severa/terapia , Criança , Pré-Escolar , Europa (Continente) , Seguimentos , Transplante de Células-Tronco Hematopoéticas/tendências , História do Século XX , História do Século XXI , Humanos , Análise Multivariada , Prognóstico , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
19.
Blood ; 115(5): 925-35, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19880495

RESUMO

T-cell immunotherapy that takes advantage of Epstein-Barr virus (EBV)-stimulated immunity has the potential to fill an important niche in targeted therapy for EBV-related cancers. To address questions of long-term efficacy, safety, and practicality, we studied 114 patients who had received infusions of EBV-specific cytotoxic T lymphocytes (CTLs) at 3 different centers to prevent or treat EBV(+) lymphoproliferative disease (LPD) arising after hematopoietic stem cell transplantation. Toxicity was minimal, consisting mainly of localized swelling at sites of responsive disease. None of the 101 patients who received CTL prophylaxis developed EBV(+) LPD, whereas 11 of 13 patients treated with CTLs for biopsy-proven or probable LPD achieved sustained complete remissions. The gene-marking component of this study enabled us to demonstrate the persistence of functional CTLs for up to 9 years. A preliminary analysis indicated that a patient-specific CTL line can be manufactured, tested, and infused for $6095, a cost that compares favorably with other modalities used in the treatment of LPD. We conclude that the CTL lines described here provide safe and effective prophylaxis or treatment for lymphoproliferative disease in transplantation recipients, and the manufacturing methodology is robust and can be transferred readily from one institution to another without loss of reproducibility.


Assuntos
Infecções por Vírus Epstein-Barr/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4/imunologia , Transtornos Linfoproliferativos/terapia , Linfócitos T Citotóxicos/imunologia , Adolescente , Transferência Adotiva/economia , Transferência Adotiva/métodos , Adulto , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/etiologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Humanos , Imunofenotipagem , Lactente , Linfoma/etiologia , Linfoma/mortalidade , Linfoma/terapia , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/mortalidade , Masculino , Taxa de Sobrevida , Linfócitos T Citotóxicos/transplante , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
20.
Blood ; 115(2): 396-407, 2010 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-19890093

RESUMO

Immunotherapy with allodepleted donor T cells (ADTs) improves immunity after T cell-depleted stem cell transplantation, but infection/relapse remain problematic. To refine this approach, we characterized the expression of surface markers/cytokines on proliferating alloreactive T cells (ATs). CD25 was expressed on 83% of carboxyfluorescein diacetate succinimidyl ester(dim) ATs, confirming this as an excellent target for allodepletion. Seventy percent of CD25(-) ATs expressed CD71 (transferrin receptor), identifying this as a novel marker to target ATs persisting after CD25 depletion. Comparison of residual alloreactivity after combined CD25/71 versus CD25 immunomagnetic depletion showed enhanced depletion of alloreactivity to host with CD25/71 depletion in both secondary (2 degrees) mixed lymphocyte reactions (P < .01) and interferon-gamma enzyme-linked immunospot assays (P < .05) with no effect on third-party responses. In pentamer/interferon-gamma enzyme-linked immunospot assays, antiviral responses to cytomegalovirus, Epstein-Barr virus, and adenovirus were preserved after CD25/71 allodepletion. CD25/71 ADTs can be redirected to recognize leukemic targets through lentiviral transfer of a chimeric anti-CD19zeta T-cell receptor. Finally, we have established conditions for clinically applicable CD25/71 allodepletion under European Union Good Manufacturing Practice conditions, resulting in highly effective, reproducible, and selective depletion of ATs (median residual alloreactivity to host in 2 degrees mixed lymphocyte reaction of 0.39% vs third-party response of 62%, n = 5). This strategy enables further clinical studies of adoptive immunotherapy with larger doses of ADTs to enhance immune reconstitution after T cell-depleted stem cell transplantation.


Assuntos
Antígenos CD/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Depleção Linfocítica , Receptores da Transferrina/imunologia , Linfócitos T/imunologia , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Regulação da Expressão Gênica/imunologia , Humanos , Transplante de Células-Tronco , Transplante Homólogo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA