RESUMO
BACKGROUND: This study evaluated the influence of circulating anti-HLA antibodies on outcomes of 97 liver allografts from deceased donors. METHODS: Human leukocyte antigen (HLA) antibody screening was performed by both complement-dependent cytotoxicity (CDC) and multiparameter Luminex microsphere-based assays (Luminex assay). RESULTS: The agreements between T- and B- cell CDC and Luminex assays were 67% and 77% for pre- and posttransplant specimens, respectively. Graft dysfunction was not associated with either positive pretransplant CDC or Luminex panel-reactive antibody (PRA) values. Likewise, positive posttransplant T- or B- cell CDC PRA values were not associated with graft dysfunction. In contrast, posttransplant Luminex PRA values were significantly higher among patients with graft dysfunction compared with subjects with good outcomes (P = .017). CONCLUSION: Posttransplant monitoring of HLA antibodies with Luminex methodology allowed identification of patients at high-risk for poor graft outcomes.
Assuntos
Ativação do Complemento , Testes Imunológicos de Citotoxicidade , Citotoxicidade Imunológica , Rejeição de Enxerto/imunologia , Antígenos HLA/imunologia , Histocompatibilidade , Isoanticorpos/sangue , Transplante de Fígado/imunologia , Monitorização Imunológica/métodos , Linfócitos B/imunologia , Biomarcadores/sangue , Fluorescência , Rejeição de Enxerto/sangue , Rejeição de Enxerto/diagnóstico , Teste de Histocompatibilidade , Humanos , Valor Preditivo dos Testes , Linfócitos T/imunologia , Fatores de Tempo , Resultado do TratamentoRESUMO
Preformed donor-specific human leukocyte antigen (HLA) antibodies have been associated with allograft dysfunction and failure. However, recipients of HLA-identical kidneys can develop acute humoral rejection, implicating putative pathogenic antibodies that are directed against non-HLA antigens. We investigated the presence of endothelial cell-reactive antibodies in 11 patients who experienced early loss of their transplanted kidneys owing to humoral rejection and 1 loss from renal venal thrombosis. We examined the potential efficacy of intravenous immunoglobulin to block the binding of these antibodies, as previously suggested for anti-HLA antibodies.
Assuntos
Anticorpos/sangue , Células Endoteliais/imunologia , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Transplante de Rim/imunologia , Brasil , Linhagem Celular , Testes Imunológicos de Citotoxicidade , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Teste de Histocompatibilidade , Humanos , Imunidade Humoral , Imunoglobulinas Intravenosas/metabolismo , Transplante Homólogo , Resultado do TratamentoRESUMO
The development of microchimerism was evaluated at different time points after infusion of a mixed population of bone marrow and spleen cells from (BALB/c x C57Bl/6)F1 mice in the presence or absence of a cardiac transplant. Microchimerism was observed in the spleen, bone marrow and thymus of transplanted BALB/c mice even after graft rejection. In the absence of transplantation, donor cells persisted especially in the thymus. The results show that despite augmentation of graft survival after donor cell infusion compared to nontreated controls, the development of microchimerism did not sustain cardiac semihistocompatible grafts. Moreover, the persistence of donor cells in the thymus in both situations suggests a role for this organ in the increased graft survival in our model.
Assuntos
Sobrevivência de Enxerto/imunologia , Transplante de Coração/imunologia , Quimeras de Transplante , Animais , Sequência de Bases , Biomarcadores , Primers do DNA , Modelos Animais de Doenças , Hipoxantina Fosforribosiltransferase/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase , Transplante HomólogoAssuntos
Antígenos de Histocompatibilidade Classe I/imunologia , Transplante de Fígado/imunologia , Complicações Pós-Operatórias/epidemiologia , Adolescente , Adulto , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/imunologia , Sensibilidade e EspecificidadeAssuntos
Soro Antilinfocitário/sangue , Transplante de Rim/imunologia , Rejeição de Enxerto/classificação , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/sangue , Teste de Histocompatibilidade , Humanos , Imunoglobulina G/sangue , Transplante de Rim/fisiologia , ReoperaçãoRESUMO
This study was designed to investigate how antiendothelial antibodies (EAbs) are involved in acute irreversible renal graft rejection. Eluates from 25 renal allografts, lost by irreversible rejection (n = 22) and by renal vein thrombosis (controls n = 3), were tested against a panel of cultured human umbilical vein endothelial cells (HUVEC). All patients were under immunosuppression at the time of nephrectomy. EAbs binding and membrane expression of adhesion molecules ELAM-1 and VCAM-1 were analyzed by flow cytometry (FACS) and by semiquantitative RT-PCR for mRNAs coding for those molecules. The absence of anti-HLA antibodies against the donor was ascertained at transplant, and before and after nephrectomy by the negativity of specific crossmatches performed using the most sensitive techniques. EAbs eluted from eight rejected kidneys bound to HUVEC. They did not induce any cytotoxicity, but their incubation with HUVEC (4 h at 37 degrees C; 2.5 mg/ml) led to upregulation of mRNAs coding for VCAM-1 (35- to 60-fold increases) and ICAM-1 (8- to 12-fold increases) as compared with control EAbs. Membrane expression of adhesion molecules was also strikingly increased, with 80% of the cells expressing VCAM-1 and 65% expressing ELAM-1 upon incubation. EAbs were detected in eight out of nine (88.8%) eluates from kidneys lost from acute vascular rejection, but in none of the 13 (0.0%) kidneys lost from other types of rejection (p < 0.0001). We conclude that EAbs, capable of activating human endothelial cells, can be recovered from acutely rejected kidneys and may play a direct role in the pathogenesis of acute rejection.
Assuntos
Anticorpos/isolamento & purificação , Endotélio Vascular/imunologia , Rejeição de Enxerto/imunologia , Transplante de Rim/imunologia , Doença Aguda , Selectina E/genética , Selectina E/isolamento & purificação , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Terapia de Imunossupressão , Rim/irrigação sanguínea , Rim/imunologia , Transplante Homólogo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/isolamento & purificaçãoAssuntos
Sobrevivência de Enxerto , Isoanticorpos/sangue , Transplante de Fígado/imunologia , Doadores de Tecidos , Adulto , Etnicidade , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Transplante de Fígado/mortalidade , Transplante de Fígado/fisiologia , Masculino , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Cytomegalovirus infection, a common complication in immunosuppressed graft recipients, bears an adverse impact on graft survival. Cytomegalovirus enhances the expression of the monotypic determinants of the class I major histocompatibility complex molecule by the endothelium, possibly rendering the endothelial cells more immunogenic and prone to attack by the allogeneic lymphocytes. In the present study, we focused on the effect of cytomegalovirus on the endothelial cell expression of different class I genes, on the relation between the extent of endothelial cell infection and the class I effect, and on the time course of the class I changes induced by the cytomegalovirus infection. Cytomegalovirus infection of primary cultures of human umbilical vein endothelial cells augmented the expression of the A2, A3, and B7 class I major histocompatibility complex genes when compared with uninfected cells. beta 2 microglobulin upregulation by the infected cells paralleled the changes in specific class I expression; this effect was significant only after 7 days after infection. Double immunocytochemical staining and fluorescence-activated cell sorter analysis revealed that the class I enhancement was uniform throughout the umbilical vein endothelial cell monolayer and not restricted to the cells that expressed cytomegalovirus early or late antigens. Ultraviolet-inactivated supernatants from infected umbilical vein endothelial cell did not increase class I expression on uninfected cells. In conclusion, cytomegalovirus might affect graft survival by amplifying the changes in class I expression beyond the sites of viral replication.