Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
1.
Trials ; 22(1): 674, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34600562

RESUMO

BACKGROUND: Moderate/severe cases of COVID-19 present a dysregulated immune system with T cell lymphopenia and a hyper-inflammatory state. This is a study protocol of an open-label, multi-center, double-arm, randomized, dose-finding phase I/II clinical trial to evaluate the safety, tolerability, alloreactivity, and efficacy of the administration of allogeneic memory T cells and natural killer (NK) cells in COVID-19 patients with lymphopenia and/or pneumonia. The aim of the study is to determine the safety and the efficacy of the recommended phase 2 dose (RP2D) of this treatment for patients with moderate/severe COVID-19. METHODS: In the phase I trial, 18 patients with COVID-19-related pneumonia and/or lymphopenia with no oxygen requirement or with an oxygen need of ≤ 2.5 liters per minute (lpm) in nasal cannula will be assigned to two arms, based on the biology of the donor and the patient. Treatment of arm A consists of the administration of escalating doses of memory T cells, plus standard of care (SoC). Treatment of arm B consists of the administration of escalating doses of NK cells, plus SoC. In the phase II trial, a total of 182 patients with COVID-19-related pneumonia and/or lymphopenia requiring or not oxygen supplementation but without mechanical ventilation will be allocated to arm A or B, considering HLA typing. Within each arm, they will be randomized in a 1:1 ratio. In arm A, patients will receive SoC or RP2D for memory T cells plus the SoC. In arm B, patients will receive SoC or RP2D for NK cells plus the SoC. DISCUSSION: We hypothesized that SARS-CoV-2-specific memory T-lymphocytes obtained from convalescent donors recovered from COVID-19 can be used as a passive cell immunotherapy to treat pneumonia and lymphopenia in moderate/severe patients. The lymphopenia induced by COVID-19 constitutes a therapeutic window that may facilitate donor engraftment and viral protection until recovery. TRIAL REGISTRATION: ClinicalTrials.gov NCT04578210 . First Posted : October 8, 2020.


Assuntos
COVID-19 , Linfopenia , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Humanos , Memória Imunológica , Células Matadoras Naturais , Linfopenia/diagnóstico , Linfopenia/terapia , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Linfócitos T , Resultado do Tratamento
2.
EClinicalMedicine ; 39: 101086, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34405140

RESUMO

BACKGROUND: Effective treatments are still needed to reduce the severity of symptoms, time of hospitalization, and mortality of COVID-19. SARS-CoV-2 specific memory T-lymphocytes obtained from convalescent donors recovered can be used as passive cell immunotherapy. METHODS: Between September and November 2020 a phase 1, dose-escalation, single centre clinical trial was conducted to evaluate the safety and feasibility of the infusion of CD45RA- memory T cells containing SARS-CoV-2 specific T cells as adoptive cell therapy against moderate/severe cases of COVID-19. Nine participants with pneumonia and/or lymphopenia and with at least one human leukocyte antigen (HLA) match with the donor were infused. The first three subjects received the lowest dose (1 × 105 cells/kg), the next three received the intermediate dose (5 × 105 cells/kg) and the last three received the highest dose (1 × 106 cells/kg) of CD45RA- memory T cells. Clinicaltrials.gov registration: NCT04578210. FINDINGS: All participants' clinical status measured by National Early Warning Score (NEWS) and 7-category point ordinal scales showed improvement six days after infusion. No serious adverse events were reported. Inflammatory parameters were stabilised post-infusion and the participants showed lymphocyte recovery two weeks after the procedure. Donor microchimerism was observed at least for three weeks after infusion in all patients. INTERPRETATION: This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent CD45RA- memory T cells is feasible and safe. FUNDING: Clinical Trial supported by Spanish Clinical Research Network PT17/0017/0013. Co-funded by European Regional Development Fund/European Social Fund. CRIS CANCER Foundation Grant to AP-M and Agencia Valenciana de Innovación Grant AVI-GVA COVID-19-68 to BS.

3.
Int J Immunogenet ; 45(3): 140-142, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29516629

RESUMO

Three new HLA class I alleles were described in the Spanish population. HLA-A*68:169 and -B*39:129 show one amino acid replacement at the α1-domain, compared to A*68:02 (P47 > L47) and -B*39:06 (S11 > A11), respectively. HLA-B*07:298 presents one nucleotide mutation within exon 1, resulting in a new amino acid position -14, L>Q, which has not been previously described in any HLA protein. Prediction of the B*07:298 signal peptide cleavage did not show significant differences in comparison with that obtained for the rest of HLA-B genes.


Assuntos
Alelos , Sequência de Bases , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígeno HLA-B7/genética , Análise de Sequência de DNA , Sequência de Aminoácidos , Antígenos HLA-A/química , Antígenos HLA-B/química , Antígeno HLA-B7/química , Haplótipos , Humanos , Peptídeos/química
5.
HLA ; 89(4): 230-234, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28205408

RESUMO

BACKGROUND: The assignment of human leukocyte antigen (HLA) null alleles is clinically relevant in the setting of stem cell transplantation. Cell surface expression profiling and mRNA processing analysis of the HLA-B allele previously designated as B*07:44, have been performed. MATERIALS AND METHODS: Cell surface expression of HLA-B*07:44 was determined using flow cytometry. Genomic full-length and HLA-B*07-specific cDNA sequencing were carried out by Sanger procedure. RESULTS: Flow cytometric analysis confirmed previous serologic results and demonstrated a lack of cell membrane expression of the HLA-B protein. The mRNA processing, studied using direct HLA-B*07-specific cDNA sequencing, revealed the presence of a unique, aberrantly spliced mRNA, with a deletion of the last 43 bp on the 5'-end of exon 4. The substitution from T to G at genomic position 1799 compared to B*07:02:01 introduced a new and stronger splice donor site at exon 4. This alternative splicing produced an mRNA containing a premature stop codon at position 280, explaining the absence of mature HLA-B7 protein on the cell surface. CONCLUSION: These findings led us to consider this HLA-B variant as a HLA null allele. The World Health Organization (WHO) Nomenclature Committee has since renamed this variant B*07:44N .


Assuntos
Processamento Alternativo , Sequência de Bases , Antígeno HLA-B7/genética , RNA Mensageiro/genética , Deleção de Sequência , Alelos , Transplante de Medula Óssea , Clonagem Molecular , Códon de Terminação , DNA Complementar/genética , DNA Complementar/imunologia , Éxons , Citometria de Fluxo , Antígeno HLA-B7/imunologia , Humanos , RNA Mensageiro/imunologia , Alinhamento de Sequência , Análise de Sequência de DNA , Terminologia como Assunto , Doadores de Tecidos
8.
Transplant Proc ; 48(9): 3043-3045, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27932143

RESUMO

An important factor affecting the success in the setting of related haploidentical hematopoietic stem cell transplantation (HSCT) is the graft-versus-leukemia effect mediated by natural killer (NK) cells when the donor displays NK alloreactivity versus the recipient. NK cell function is regulated by killer immunoglobulin-like receptors (KIR) and it has been described that donor KIR genotype influences transplantation outcome. This has led to a requirement of laboratories to have a quality assurance program for validation and control of their KIR genotyping methods. The goal of the 1st and 2nd Spanish KIR Genotyping Workshops was to provide an external proficiency testing program in KIR genotyping for Spanish immunology and transplant laboratories. These workshops were conducted during the years 2014-2016 and consisted of 17 participating laboratories typing a set of 20 samples. The presence/absence of 16 mandatory KIR loci (2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 2DP1, 3DL1, 3DL2, 3DL3, 3DS1, and 3DP1) was evaluated per sample. Methods for KIR genotyping included polymerase chain reaction with the use of sequence-specific primers and sequence-specific oligoprobes. Consensus typing was reached in all samples, and the performance of laboratories in external proficiency testing was satisfactory in all cases. The polymorphism detected in the small sample studied in both workshops is indicative of an ample variety of KIR gene profiles in the Spanish population.


Assuntos
Seleção do Doador/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Receptores KIR/genética , Frequência do Gene , Genótipo , Humanos , Células Matadoras Naturais/imunologia , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Controle de Qualidade
11.
HLA ; 88(1-2): 35-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27297335

RESUMO

In this report we describe a case of somatic mutation in the HLA-B gene in the tumour cells of a patient with acute myelogenous leukaemia (AML). Routine human leukocyte antigen (HLA) typing of patient by serology and molecular methodologies rendered discrepant results regarding the expression of a B*15:01 antigen. Sequencing-based typing of a patient's sample including a very high percentage of blast cells revealed the presence of one nucleotide insertion at exon 3, position 440, codon 123. This insertion resulted in a reading frame shift and a premature stop codon at position 152. The mutation was absent in a sample obtained when the patient was in remission. This case report points out the relevance of the sample source for HLA typing in patients with haematological malignancies.


Assuntos
Alelos , Éxons , Mutação da Fase de Leitura , Antígeno HLA-B15/genética , Leucemia Mieloide Aguda/genética , Sequência de Bases , Códon sem Sentido , Feminino , Expressão Gênica , Genótipo , Antígeno HLA-B15/imunologia , Teste de Histocompatibilidade , Humanos , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Pessoa de Meia-Idade , Alinhamento de Sequência , Análise de Sequência de DNA
12.
Bone Marrow Transplant ; 51(9): 1211-6, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27088380

RESUMO

Haploidentical hematopoietic stem cell transplantation using T-cell-depleted grafts is a valid option for pediatric patients with hematological malignancies in need of an allogeneic transplantation and lacking an HLA-identical donor. Seventy-five transplantations were performed in 70 patients. Thirty-eight patients had ALL, 32 had AML, 3 had advanced myelodysplastic syndromes and 2 juvenile myelomonocytic leukemia; 19 were in first CR, 30 in second CR, 12 in greater than second CR and 14 were considered to be in refractory disease at time of transplantation. Four patients developed graft failure. Among engrafted patients, the median time to neutrophil and platelet recovery was 13 (range 8-20) and 10 days (range 8-70), respectively. In 64 (85%) cases, ⩾1 infections were diagnosed after transplant. The probability of nonrelapse mortality by day +100 after transplantation was 10±4%. With a median follow-up of 22 months, the probability of relapse was 32±6% and disease-free survival was 52±6%. Haploidentical transplantation using CD3/CD19 depletion is associated with encouraging results especially in patients in early phase of disease. Killer-cell Ig-like receptor B haplotype donors confer a rapid natural killer cells expansion early after transplantation, resulting in lower probability of relapse and suggesting a GvL effect apart from graft-versus-host reactions. Donor infusion of high numbers of CD34+ cells is recommended in order to improve T-cell reconstitution.


Assuntos
Neoplasias Hematológicas/terapia , Depleção Linfocítica/métodos , Transplante Haploidêntico/métodos , Adolescente , Adulto , Aloenxertos/citologia , Aloenxertos/imunologia , Antígenos CD19/isolamento & purificação , Complexo CD3/isolamento & purificação , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/mortalidade , Humanos , Lactente , Infecções/induzido quimicamente , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/transplante , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores KIR , Análise de Sobrevida , Doadores de Tecidos , Transplante Haploidêntico/efeitos adversos , Transplante Haploidêntico/mortalidade , Resultado do Tratamento , Adulto Jovem
19.
Transplant Proc ; 44(9): 2548-50, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146450

RESUMO

BACKGROUND: The presence of circulating antibodies (CA) against human leukocyte antigen (HLA) and major-histocompatibility-complex class I-related chain A (MICA) antigens has been associated with worse renal function and reduced kidney allograft survival. We sought to describe the presence of donor-specific anti-HLA antibodies, non-donor specific antibodies, and antibodies against MICA antigens among a cohort of renal transplant recipients with respect to their evolution effects on renal function and occurrence of an acute rejection episode (AR) after transplantation. METHODS: This prospective study of 22 renal transplant recipients of deceased donor kidneys underwent studies of antibodies before and 3 months after grafting using Luminex technology. RESULTS: Ten patients (five men and five women) showed preexistent CA. Comparing patients with versus without preformed CA, we did not observe a significant difference in donor and recipient age or gender. Eight patients (80%) with CA had undergone induction treatment with anti-human-activated T-lymphocyte rabbit immunoglobulin and 2 (20%) with basiliximab. There were no differences between groups regarding the incidence of acute rejection episodes (ARE n = 3 each). There was one case of Banff grade IIB ARE in a patient without preexisting CA; the other episodes were low-grade cellular responses. There were no differences in other variables including cold ischemia time, HLA mismatches, panel-reactive antibody levels, number of transfusions, cytomegalovirus infection or renal function at discharge and 3 months later. Retransplantation was the only factor associated with preformed CA. Retransplantation and preformed CA were associated with CA at 3 months after transplantation. CONCLUSIONS: CA monitoring is important for highly sensitized renal transplants, although our experience failed to show a difference in graft survival or renal function in the first 3 months' follow-up.


Assuntos
Antígenos HLA/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Isoanticorpos/sangue , Transplante de Rim/imunologia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/uso terapêutico , Soro Antilinfocitário/uso terapêutico , Basiliximab , Biomarcadores/sangue , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/cirurgia , Humanos , Imunossupressores/uso terapêutico , Incidência , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Monitorização Imunológica , Estudos Prospectivos , Proteínas Recombinantes de Fusão/uso terapêutico , Reoperação , Fatores de Risco , Espanha/epidemiologia , Fatores de Tempo , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA