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1.
Bone Marrow Transplant ; 42(12): 819-27, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18711345

RESUMO

In total, 124 adult patients in remission after allogeneic hematopoietic SCT (HSCT) participated in a cross-sectional study to assess health-related quality of life (HRQL). Assessment of HRQL was carried out using two questionnaires: the (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy (FACT) with specific modules for BMT (FACT-BMT). Transplanted patients differed from healthy controls in many HRQL-related dimensions in the EORTC QLQ-C30: social functioning 73.4 versus 85.8, P<0.0001; role functioning 74.6 versus 83.3, P<0.004; physical functioning 83.9 versus 89.9, P<0.001; emotional functioning 72.2 versus 82.8, P<0.0001 but were not significant for global HRQL 71.2 versus 75.3, P<0.03. In total, 60% of the patients returned to work after HSCT; 31% part time and 29% full time. Age at HSCT and employment status were significantly associated with HRQL. Other factors such as disease and disease stage and especially the occurrence of late complications did not impact the perception of HRQL. This study suggests that the perception of HRQL after HSCT differs from the general population. Issues to increase work-related capabilities and improve social support need to be addressed.


Assuntos
Emprego , Transplante de Células-Tronco Hematopoéticas , Qualidade de Vida , Adulto , Fatores Etários , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ajustamento Social , Apoio Social , Sobreviventes , Transplante Homólogo , Adulto Jovem
2.
Br J Cancer ; 94(12): 1770-6, 2006 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-16685263

RESUMO

We present the long-term results of 18 chemotherapy relapsed indolent (N = 12) or transformed (N = 6) NHL patients of a phase II anti-CD20 (131)I-tositumomab (Bexxar) therapy study. The biphasic therapy included two injections of 450 mg unlabelled antibody combined with (131)I-tositumomab once as dosimetric and once as therapeutic activity delivering 75 or 65 cGy whole-body radiation dose to patients with normal or reduced platelet counts, respectively. Two patients were not treated due to disease progression during dosimetry. The overall response rate was 81% in the 16 patients treated, including 50% CR/CRu and 31% PR. Median progression free survival of the 16 patients was 22.5 months. Median overall survival has not been reached after a median observation of 48 months. Median PFS of complete responders (CR/CRu) has not been reached and will be greater than 51 months. Short-term side effects were mainly haematological and transient. Among the relevant long-term side effects, one patient previously treated with CHOP chemotherapy died from secondary myelodysplasia. Four patients developed HAMA. In conclusion, (131)I-tositumomab RIT demonstrated durable responses especially in those patients who achieved a complete response. Six of eight CR/CRu are ongoing after 46-70 months.


Assuntos
Anticorpos Monoclonais/toxicidade , Antineoplásicos/toxicidade , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/mortalidade , Adulto , Idoso , Anticorpos Monoclonais/farmacocinética , Antineoplásicos/farmacocinética , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Análise de Sobrevida , Taxa de Sobrevida , Tempo , Resultado do Tratamento
3.
Bone Marrow Transplant ; 37(10): 909-16, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16565739

RESUMO

It is currently unknown what degree of human leukocyte antigen (HLA)-mismatching is acceptable in unrelated donor hematopoietic stem cell transplantation (UD-HSCT). Mismatches at some loci may be more permissive than others. We have analyzed the effect of high-resolution HLA-matching on outcome of all 214 consecutive recipients of UD-HSCT carried out in Switzerland. All typing was by the Swiss reference laboratory. Donor-recipient pairs were HLA-10/10 matched (n=130) or mismatched for either HLA-A/-B/-DRB1/multiple loci (n=33; (HLA-A/-B=10); (-DRB1=8); (multiple=15)); HLA-C (n=29) or HLA-DQ/-DRB3 (n=22; (DQ=16); (-DRB1=6)). The median follow-up was 32 months. Survival probabilities (+/-95% confidence interval) at 3 years were 57 (+/-10)% for recipients of HLA 10/10-matched transplants, 53 (+/-22)% for recipients of HLA-DQ/-DRB3-mismatched transplants, 44 (+/-20)% for recipients of HLA-C-mismatched transplants and 0% for recipients of transplants mismatched at HLA-A/-B/-DRB1/multiple loci (P<0.0001). In multivariate analyses, HLA compatibility was the variable most significantly associated with survival and treatment-related mortality. We found important differences in survival in recipients of UD-HSCT with best results for transplants from 10/10 matched donors. Single mismatches at HLA-DQ/-DRB3 were well tolerated, mismatches at HLA-C had intermediate results and mismatches at HLA-A/-B/-DRB1/multiple loci resulted in poor survival.


Assuntos
Antígenos HLA/química , Teste de Histocompatibilidade/métodos , Histocompatibilidade , Transplante de Células-Tronco/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Suíça
4.
Bone Marrow Transplant ; 35(12): 1171-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15880127

RESUMO

Patients with hematological malignancies are well nourished prior to allogeneic hematopoietic stem cell transplantation (HSCT). HSCT and associated complications can affect body composition. The study evaluated cross-sectionally the prevalence and longitudinally the changes in lean body mass index (LBMI) in HSCT patients. Patients (n=82) were classified as normal or low LBMI. Logistic regression analyses were used to estimate odds ratios (OR) for low vs normal LBMI, between healthy volunteers and patients; for limited or extensive vs no chronic graft-versus-host-disease (GVHD); and for decreased (Karnofsky <80) vs normal functional status (>80). Patients were significantly more likely to have low LBMI at 6, 12 months, 2-3, 4-6 and >6 years than volunteers. In all, 38% of patients were below pre-HSCT LBMI at 4-6 years post-HSCT. Low LBMI was significantly associated with steroid treatment (OR 2.6, confidence intervals (CI) 1.3-5.2, P=0.008); limited (OR 5.5, CI 1.7-18.5, P=0.005) or extensive chronic GVHD (OR 20.3, CI 5.7-71.6, P<0.001); and decreased performance status (Karnofsky scores of < or =80) (OR 2.7, CI 1.3-5.9, P=0.01). Patients were more likely to have low LBMI than volunteers. Chronic GVHD and low performance status were associated with low LBMI; thus, complications and/or treatment increase the likelihood of low LBMI.


Assuntos
Composição Corporal , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Medula Óssea/efeitos adversos , Estudos de Casos e Controles , Doença Enxerto-Hospedeiro , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/terapia , Humanos , Avaliação de Estado de Karnofsky , Estudos Longitudinais , Razão de Chances , Estudos Retrospectivos , Esteroides/efeitos adversos , Esteroides/uso terapêutico , Transplante Homólogo
5.
Eur J Haematol ; 73(6): 441-6, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15522068

RESUMO

We report a case of pure red cell aplasia (PRCA) following allogeneic stem cell transplantation (SCT) with major ABO mismatch which proved resistant to all standard treatment options such as change in immunosuppressive treatment, high-dose erythropoietin (EPO) or plasma exchange. We therefore proceeded to administer five cycles of Rituximab therapy, without success. Finally, escalating doses of donor-derived leukocyte infusion (DLI) resolved the PRCA of our patient 415 d after bone-marrow transplantation (BMT) and 140 d after the first infusion of donor leukocytes. A review of the literature shows the efficacy of various treatments; the role of DLI and other treatment options are discussed. Furthermore, the underlying pathophysiological mechanisms especially with regard to the role of NK cells in alloreactivity after allogeneic SCT are explained.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transfusão de Leucócitos , Aplasia Pura de Série Vermelha/etiologia , Transplante Homólogo/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transfusão de Sangue , Terapia Combinada , Citarabina/administração & dosagem , Resistência a Medicamentos , Eritropoetina/uso terapêutico , Humanos , Idarubicina/administração & dosagem , Imunossupressores/uso terapêutico , Células Matadoras Naturais/imunologia , Leucemia Mielomonocítica Aguda/tratamento farmacológico , Leucemia Mielomonocítica Aguda/terapia , Masculino , Pessoa de Meia-Idade , Plasmaferese , Aplasia Pura de Série Vermelha/imunologia , Aplasia Pura de Série Vermelha/fisiopatologia , Aplasia Pura de Série Vermelha/terapia , Indução de Remissão , Rituximab , Transplante Homólogo/imunologia
7.
Bone Marrow Transplant ; 34(3): 249-55, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15195077

RESUMO

HLA-incompatibility is a major factor associated with outcome of allogeneic stem cell transplantation, but little is known on the impact of isolated HLA-C mismatches. We analyzed the outcome of 114 CML patients transplanted with marrow from unrelated donors of whom 24 were mismatched for HLA-C only (9/10 match). Univariate estimates of 5-year survival (SRV) (median follow-up: 47 months) in the HLA-matched group were 68+/-12 vs 42+/-20% (P=0.03) for the patients mismatched for HLA-C only and 33+/-33% in the mismatched group (non-HLA-C single mismatches and multiple mismatches) (P=0.0004). Disease stage, GVHD-prophylaxis (T-cell depletion), CMV-status and HLA-incompatibility were the risk factors associated (all P< or =0.005) with poor outcome. In the multivariate analysis, patients mismatched for loci other than HLA-C were at high risk of an adverse outcome (death: RR, 2.9; CI, 1.6-5.4, P=0.008, transplant-related mortality (TRM): RR, 3; CI, 1.5-5.9, P=0.0015). For patients mismatched for HLA-C only, the increased risk was of borderline significance (death: RR, 1.9; CI, 1-3.9, P=0.06, TRM: RR, 2.1; CI, 1-4.5, P=0.07). In spite of their lower expression, HLA-C antigens still represent relevant transplantation barriers that should be considered when searching for an unrelated donor.


Assuntos
Transplante de Medula Óssea/imunologia , Antígenos HLA-C/imunologia , Teste de Histocompatibilidade , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/cirurgia , Transplante de Células-Tronco , Adulto , Causas de Morte , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Leucemia Linfocítica Crônica de Células B/mortalidade , Doadores Vivos , Masculino , Segunda Neoplasia Primária/mortalidade , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos
8.
Br J Dermatol ; 148(1): 154-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12534612

RESUMO

Amyloid elastosis is a rare variant of primary systemic amyloidosis characterized by amyloid deposited around elastic fibres. Only two cases, with pseudoxanthoma elasticum-like features and fatal outcome, have been reported. A 56-year-old woman presented with polyneuropathy and a diffuse plane xanthoma-like eruption. Light and electron microscopy studies revealed deposits of amyloid L encasing either normal-looking or short, fragmented elastic fibres in the dermis in a pattern characteristic of amyloid elastosis. The patient had medullary plasmocytosis with lambda light chain restricted expression and underwent autologous stem cell transplantation, which resulted in progressive regression of mucocutaneous signs and stabilization of the polyneuropathy. Our case extends the spectrum of clinical and histopathological presentations of amyloid elastosis. Haematopoietic cell transplantation might improve outcome in patients with multisystem disease.


Assuntos
Amiloidose/terapia , Doenças do Tecido Conjuntivo/terapia , Tecido Elástico/ultraestrutura , Transplante de Células-Tronco Hematopoéticas , Amiloidose/patologia , Doenças do Tecido Conjuntivo/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Pele/ultraestrutura
10.
Scand J Gastroenterol ; 37(4): 493-6, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11989843

RESUMO

We report the case of a 32-year-old man with a low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the parotid gland associated with Sjögren syndrome. He underwent an upper endoscopy as part of the screening of a gastric localization which showed a diffuse non-specific gastritis. However, endoscopic ultrasonography (EUS) evidenced a focal wall thickening of the vertical portion of the smaller curvature. EUS-guided biopsies of this area disclosed a MALT lymphoma, whereas biopsies under endoscopy concluded to mild chronic gastritis. The search for Helicobacter pylori infection remained negative. Four months after treatment with anti-CD20 antibodies, EUS showed a diminution of the abnormal thickening of the second layer. Regression was confirmed histologically on new EUS-guided biopsies. MALT lymphoma is usually considered a localized disease; however, dissemination is probably more frequent than initially believed. Our case reflects the importance of a systematic screening for a gastric localization in patients with MALT lymphoma of the salivary glands. In this situation, association to autoimmune disease such as Sjögren syndrome is more likely to explain the gastric location than infection with H. pylori. Endoscopic ultrasonography has a major impact for the staging of gastric MALT lymphoma, but may also help diagnose focal infiltration by the disease.


Assuntos
Endossonografia , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Parotídeas/diagnóstico , Neoplasias Gástricas/diagnóstico , Ultrassonografia de Intervenção , Adulto , Gastrite/complicações , Humanos , Linfoma de Zona Marginal Tipo Células B/complicações , Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Masculino , Neoplasias Primárias Múltiplas/complicações , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias Parotídeas/complicações , Síndrome de Sjogren/complicações , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico por imagem
11.
Osteoporos Int ; 12(10): 880-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11716193

RESUMO

Osteoporosis is a major complication of organ transplantation. Little is known about the risk of developing osteoporosis in bone marrow transplant (BMT) recipients. We studied early and late changes in bone mineral density (BMD), as well as biochemical markers of bone remodeling, in patients at the time of allogeneic BMT (alloBMT) and up to 13 years thereafter. In a cross-sectional study, 102 patients (40 women, 62 men, mean age +/- SEM, 38.9 +/- 1.6 years) were segregated into a first group (A, n = 48) and evaluated before or during the first weeks (mean +/- SD 0.3 +/- 0.1 month, range -0.5 to 3 months) following alloBMT, and a second group (B, n = 54) studied 60.1 +/- 5.6 months (range 6-156 months) following alloBMT. Lumbar spine (LS) BMD was similar in groups A and B and was within normal limits. In contrast, femoral neck (FN) Z- and T-scores were significantly decreased in group B compared with group A (-0.68 +/- 0.14 vs -0.03 +/- 0.14 SD and -0.84 +/- 0.14 vs -0.22 +/- 0.14 SD, respectively; p < or = 0.002). Osteopenia (T-score between -1 and -2.5 SD) was present in 35% of group A and 43% of group B patients (NS). Osteoporosis (T-score < -2.5 SD) was detected in 7% of group B patients, but in none of those in group A (p = 0.05). In a longitudinal study, 56 subjects were evaluated at the time of alloBMT, and 33 and 23 were studied 6 or 12 months later, respectively (13 women, 20 men, 37.5 +/- 1.6 years). All were treated with supplements of calcium and vitamin D. Amenorrheic women received hormone replacement therapy (HRT). Three-monthly pamidronate infusions were given to 15 men and 10 non-amenorrheic women who were osteopenic/osteoporotic or had elevated baseline bone turnover markers. Mean baseline LS and FN Z- and T-scores were within normal range. Six months after BMT, FN BMD decreased by 4.2 +/- 0.7% (p < 0.001), and whole body BMD and bone mineral content by 1.5 +/- 0.4% and 3.1 +/- 0.6%, respectively (p < or = 0.0001). Twelve months after the graft, there was no further significant bone loss and only FN BMD decrease remained significantly different compared with baseline (-5.6 +/- 1.1%, p < or = 0.0001). These results indicate that the risk of decreased BMD is higher for the femoral neck than the lumbar spine and whole body levels in patients with allogeneic bone marrow transplantation, and that bone loss occurs mainly during the first 6 months after the graft.


Assuntos
Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/etiologia , Transplante de Medula Óssea/efeitos adversos , Colo do Fêmur/fisiologia , Vértebras Lombares/fisiologia , Adolescente , Adulto , Biomarcadores/análise , Doenças Ósseas Metabólicas/fisiopatologia , Remodelação Óssea/fisiologia , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteoporose/etiologia , Osteoporose/metabolismo , Transplante Homólogo
12.
Trends Immunol ; 22(3): 136-41, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11286728

RESUMO

Animal models have revealed the rules for the organization of mature T-cell pools. However, in humans, little is known about memory T cells, which differ in lifespan and in the number of times that the same antigen is encountered. Here, Nathalie Rufer and colleagues discuss their findings in stem-cell-transplanted patients, which provide interesting data on the human T-cell compartment.


Assuntos
Células-Tronco Hematopoéticas/imunologia , Memória Imunológica/imunologia , Linfócitos T/imunologia , Animais , Transplante de Células-Tronco Hematopoéticas , Homeostase/imunologia , Humanos , Ativação Linfocitária/imunologia
13.
Int J Radiat Oncol Biol Phys ; 49(4): 1071-7, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11240249

RESUMO

PURPOSE: This study was performed to retrospectively assess the potential influence of total-body irradiation (TBI) dose on overall survival in patients undergoing allogeneic bone-marrow transplants (BMT) for hematologic malignancies. METHODS AND MATERIALS: Between October 1984 and December 1996, 116 patients were conditioned with high-dose chemotherapy and fractionated TBI before allogeneic BMT. The median age was 34 years (range 3-60). The TBI dose was given in 6 fractions, twice-a-day, over 3 days before BMT. The total dose was 10 Gy in 24 patients, 12 Gy in 66 patients, and 13.5 Gy in 26 patients. RESULTS: TBI dose was inversely correlated with overall survival. Five-year survival was 62% for patients conditioned with 10 Gy, 55% for patients conditioned with 12 Gy, and 46% for patients conditioned with 13.5 Gy. Age at BMT was also independently correlated with survival, with the best outcome for patients < 40 years old. CONCLUSION: A TBI dose (fractionated) > 10 Gy may not necessarily be associated with a better outcome in patients undergoing allogeneic bone-marrow transplant for hematologic malignancies.


Assuntos
Transplante de Medula Óssea/mortalidade , Leucemia Mieloide Aguda/mortalidade , Síndromes Mielodisplásicas/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Condicionamento Pré-Transplante/mortalidade , Irradiação Corporal Total/mortalidade , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea/métodos , Bussulfano/uso terapêutico , Criança , Pré-Escolar , Ciclofosfamida/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Feminino , Humanos , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Radiossensibilizantes/uso terapêutico , Dosagem Radioterapêutica , Estudos Retrospectivos , Tiotepa/uso terapêutico , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Irradiação Corporal Total/métodos
14.
Blood ; 97(2): 575-7, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11154240

RESUMO

Using quantitative fluorescence in situ hybridization and flow cytometry, the telomere length of telomere repeat sequences after stem cell transplantation (SCT) were measured. The study included the telomeres of peripheral blood monocytes that should reflect the length of telomeres in stem cells and the telomeres of T lymphocytes that could shorten as a result of peripheral expansion. The loss of telomeres in monocytes and in memory T cells, although accelerated initially, became comparable to the loss of telomeres in healthy controls from the second year after transplantation. In addition, the telomere length in the naive T cells that were produced by the thymus was comparable to the telomere length in the naive T cells of the donor. Compared to the total length of telomeres available, the loss of telomere repeats in leukocytes after SCT resembles the accelerated shortening seen in early childhood and remains, therefore, relatively insignificant.


Assuntos
Hematopoese/genética , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Telômero/fisiologia , Adulto , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/ultraestrutura , Técnicas de Cultura de Células , Divisão Celular/genética , Seguimentos , Humanos , Hibridização in Situ Fluorescente , Leucemia/sangue , Leucemia/terapia , Monócitos/citologia , Monócitos/ultraestrutura , Linfócitos T/citologia , Linfócitos T/ultraestrutura , Fatores de Tempo
15.
J Pediatr Hematol Oncol ; 23(7): 456-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11878582

RESUMO

A girl with resistant acute myeloid leukemia (AML) had a stem cell transplantation. Preceding transplantation, she had recurrent pneumonitis. No causative agent was identified. Despite several antibiotics including high-dose liposomal amphotericin-B, pulmonary infection progressed. Aspergillosis, always considered, could not be documented. She died from cardiac arrest on the second day after transplantation, with no forewarning of previous heart disease. Pericardial and myocardial aspergillosis was an autopsy finding. Pericardial and myocardial aspergillosis, rare manifestations of systemic aspergillosis, should be considered in any immunocompromised patient with long-lasting pulmonary infection, even in the absence of specific cardiac findings.


Assuntos
Aspergilose/microbiologia , Miocardite/microbiologia , Pericardite/microbiologia , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Aspergillus/isolamento & purificação , Criança , Evolução Fatal , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Hospedeiro Imunocomprometido , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/microbiologia , Miocardite/diagnóstico , Miocardite/tratamento farmacológico , Pericardite/diagnóstico , Pericardite/tratamento farmacológico
16.
Blood ; 96(6): 2299-303, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10979980

RESUMO

To evaluate the importance of the thymus for the reconstitution of immunity in recipients of a T-cell-depleted bone marrow, we measured the appearance of CD4(+)CD45RA(+)RO(-) naive T cells (thymic rebound), restoration of the diversity of the T-cell-receptor (TCR) repertoire and the response to vaccinations with tetanus toxoid (TT). Repopulation by CD4(+)CD45RA(+)RO(-) thymic emigrants varied among patients, starting at approximately 6 months after transplantation. Young patients reconstituted swiftly, whereas in older patients, the recovery of normal numbers of naive CD4(+) T cells could take several years. Restoration of TCR diversity was correlated with the number of naive CD4(+)CD45RA(+)RO(-) T cells. Moreover, the extent of the thymic rebound correlated with the patient's capacity to respond to vaccinations. Patients without a significant thymic rebound at the moment of vaccination (CD4(+)CD45RA(+)RO(-) T cells less than 30 microL) did not respond, or responded only marginally even after 3 boosts with TT. We conclude that during the first year after transplantation, the absence of an immune response is due mainly to the loss of an adequate T-cell repertoire. Restoration of the repertoire can come only from a thymic rebound that can be monitored by measuring the increase of CD4(+)CD45RA(+)RO(-) naive T cells. This will allow postponing revaccinations to a moment when the patient will be able to respond more effectively. This may be particularly useful in the elderly patient who, owing to low thymic activity, might not yet be able to respond 1 year after transplant when revaccinations are usually scheduled.


Assuntos
Transplante de Medula Óssea , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/terapia , Linfócitos T/imunologia , Timo/imunologia , Adolescente , Adulto , Antígenos CD4 , Humanos , Antígenos Comuns de Leucócito , Depleção Linfocítica , Pessoa de Meia-Idade , Fatores de Tempo , Transplante Homólogo
17.
Eur J Immunol ; 29(12): 3987-94, 1999 12.
Artigo em Inglês | MEDLINE | ID: mdl-10602008

RESUMO

We have studied the alterations in CD45R phenotypes of CD4(+)CD45RA(-)RO(+) T cells in recipients of T cell-depleted bone marrow grafts. These patients are convenient models because early after transplantation, their T cell compartment is repopulated through expansion of mature T cells and contains only cells with a memory phenotype. In addition, re-expression of CD45RA by former CD4(+)CD45RA(-) T cells can be accurately monitored in the pool of recipient T cells that, in the absence of recipient stem cells, can not be replenished with CD45RA(+) T cells through the thymic pathway. We found that CD4(+)CD45RA(-)RO(+) recipient T cells could re-express CD45RA but never reverted to a genuine CD4(+)CD45RA(+)RO(-) naive phenotype. Even 5 years after transplantation, they still co-expressed CD45RO. In addition, the level of CD45RA and CD45RC expression was lower ( approximately 35 %) than that of naive cells. In contrast, the level of CD45RB expression was comparable to that of naive cells. We conclude that CD4(+)CD45RA(-)RO(+) T cells may re-express CD45(high) isoforms but remain distinguishable from naive cells by their lower expression of CD45RA / RC and co-expression of CD45RO. Therefore, it is likely that the long-lived memory T cell will be found in the population expressing both low and high molecular CD45 isoforms.


Assuntos
Memória Imunológica/imunologia , Antígenos Comuns de Leucócito/imunologia , Linfócitos T/imunologia , Adulto , Transplante de Medula Óssea , Antígenos CD4/imunologia , Humanos , Memória Imunológica/genética , Antígenos Comuns de Leucócito/genética , Masculino , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Imunologia de Transplantes
19.
Blood ; 92(11): 4464-71, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9834254

RESUMO

We have studied the reconstitution of the T-cell compartment after bone marrow transplantation (BMT) in five patients who received a graft-versus-host disease (GVHD) prophylaxis consisting of methotrexate, cyclosporin, and 10 daily injections (day -4 to day +5) of Campath-1G. This treatment eliminated virtually all T cells (7 +/- 8 T cells/microL at day 14) which facilitated the analysis of the thymus-dependent and independent pathways of T-cell regeneration. During the first 6 months, the peripheral T-cell pool was repopulated exclusively through expansion of residual T cells with all CD4(+) T cells expressing the CD45RO-memory marker. In two patients, the expansion was extensive and within 2 months, the total number of T cells (CD8>>CD4) exceeded 1,000/microL. In the other three patients, T cells remained low (87 +/- 64 T cells/microL at 6 months) and remained below normal values during the 2 years of the study. In all patients, the first CD4(+)CD45RA+RO- T cells appeared after 6 months and accumulated thereafter. In the youngest patient (age 13), the increase was relatively fast and naive CD4(+) T cells reached normal levels (600 T cells/microL) 1 year later. In the four adult patients (age 25 +/- 5), the levels reached at that time-point were significantly lower (71 +/- 50 T cells/microL). In all patients, the T-cell repertoire that had been very limited, diversified with the advent of the CD4(+)CD45RA+RO- T cells. Cell sorting experiments showed that this could be attributed to the complexity of the T-cell repertoire of the CD4(+)CD45RA+RO- T cells that was comparable to that of a normal individual and that, therefore, it is likely that these cells are thymic emigrants. We conclude that after BMT, the thymus is essential for the restoration of the T-cell repertoire. Because the thymic activity is restored with a lag time of approximately 6 months, this might explain why, in particular in recipients of a T-cell-depleted graft, immune recovery is delayed.


Assuntos
Transplante de Medula Óssea , Neoplasias Hematológicas/terapia , Linfócitos T/imunologia , Timo/imunologia , Adolescente , Adulto , Movimento Celular/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunofenotipagem , Imunossupressores/uso terapêutico , Subpopulações de Linfócitos T/imunologia , Imunologia de Transplantes
20.
Bone Marrow Transplant ; 22(9): 895-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9827818

RESUMO

To study sensitisation to minor histocompatibility antigens (mHag) before and after BMT, we measured antidonor CTL activity in five patients who had rejected their graft, and in a control group of 10 leukemic patients who engrafted without complications. All patients were transplanted with marrow from an HLA-identical sibling. Fourteen patients were conditioned with cyclophosphamide (120 mg/kg) and TBI (1350 cGy) and received a T cell-depleted graft, while one patient with aplastic anaemia received cyclophosphamide alone and unmanipulated marrow. Before transplantation, anti-donor CTL activity was detected in two of the 15 patients. These patients rejected their grafts at days 21 and 58, respectively. In the other three patients who rejected their grafts at days 41, 60 and 250, CTL activity was found only after transplantation. In contrast, no anti-donor CTLs could be detected at any time in the 10 patients who engrafted permanently. We have identified some of the mHags recognised during graft rejection by cloning and subsequent specificity analysis of the recipient CTLs. In the patient who rejected at day 41 without detectable immunisation before BMT, the response was directed against HA-1, a minor antigen known to play a role in GVHD. In the other combinations, a significant part of the CTL activity was directed against the male antigen H-Y. In the patient who rejected the marrow of her HLA-identical brother at day 250, two clones recognised H-Y, while five others recognised at least three distinct autosomal mHags. This patient had an HLA-identical sister who expressed only one autosomal mHag that had been recognised by one single T cell clone. After re-transplantation with the marrow of this second donor, the CTL activity could no longer be detected and the patient engrafted without further complications.


Assuntos
Transplante de Medula Óssea/imunologia , Citotoxicidade Imunológica , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Menor/imunologia , Feminino , Humanos , Masculino , Imunologia de Transplantes , Transplante Homólogo
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