RESUMEN
DNA methylation is thought to induce transcriptional silencing through the combination of two mechanisms: the repulsion of transcriptional activators unable to bind their target sites when methylated, and the recruitment of transcriptional repressors with specific affinity for methylated DNA. The Methyl CpG Binding Domain proteins MeCP2, MBD1 and MBD2 belong to the latter category. Here, we present MBD2 ChIPseq data obtained from the endogenous MBD2 in an isogenic cellular model of oncogenic transformation of human mammary cells. In immortalized (HMEC-hTERT) or transformed (HMLER) cells, MBD2 was found in a large proportion of methylated regions and associated with transcriptional silencing. A redistribution of MBD2 on methylated DNA occurred during oncogenic transformation, frequently independently of local DNA methylation changes. Genes downregulated during HMEC-hTERT transformation preferentially gained MBD2 on their promoter. Furthermore, depletion of MBD2 induced an upregulation of MBD2-bound genes methylated at their promoter regions, in HMLER cells. Among the 3,160 genes downregulated in transformed cells, 380 genes were methylated at their promoter regions in both cell lines, specifically associated by MBD2 in HMLER cells, and upregulated upon MBD2 depletion in HMLER. The transcriptional MBD2-dependent downregulation occurring during oncogenic transformation was also observed in two additional models of mammary cell transformation. Thus, the dynamics of MBD2 deposition across methylated DNA regions was associated with the oncogenic transformation of human mammary cells.
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Transformación Celular Neoplásica/genética , Metilación de ADN , Proteínas de Unión al ADN/metabolismo , Proteínas Represoras/metabolismo , Sitios de Unión , Mama/citología , Línea Celular , Línea Celular Transformada , Regulación hacia Abajo , Células Epiteliales/metabolismo , Femenino , Proteínas de Homeodominio/metabolismo , Humanos , Fenotipo , Telomerasa/genética , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Homeobox 1 de Unión a la E-Box con Dedos de ZincRESUMEN
We report herein the results we obtained and the limitations we experienced during the production and use of a bank of Epstein-Barr virus (EBV)-transformed human cytotoxic T lymphocytes (EBV-CTLs). To assess the feasibility and toxicity of this strategy, we selected and stored, in liquid nitrogen, 4 billion EBV-CTLs from each of the 13 selected donors. Subsequently, in a multicenter phase I/II study, 11 patients with EBV-associated lymphoma resistant to conventional treatments received 1-3 doses of 5 million EBV-CTLs/kg with 1-3 and 0-4 compatibilities for human leukocyte antigen (HLA)-I and HLA-II, respectively. Except for one event of fever after injection, no immediate or delayed toxicity, no graft versus host disease, and no graft rejection attributable to CTL infusion were observed. Three patients presented complete remission and 1 partial remission after treatment. Considering the clinical options currently available, and the constrains associated with CTL preparation and implementation, we conclude that CTL banks should consist of a reasonably small number of cell lines with documented specificities. This objective could be more easily achieved if the few homozygous donors for the most frequent HLA alleles of the targeted population could be made available for such a project.
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Infecciones por Virus de Epstein-Barr/terapia , Herpesvirus Humano 4/inmunología , Inmunoterapia Adoptiva , Linfoma/terapia , Linfocitos T Citotóxicos/inmunología , Adolescente , Adulto , Anciano , Línea Celular , Niño , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/virología , Estudios de Factibilidad , Femenino , Humanos , Linfoma/inmunología , Linfoma/virología , Masculino , Persona de Mediana Edad , Carga Viral , Adulto JovenRESUMEN
BACKGROUND: The risks after unrelated-donor haemopoietic-cell transplantation with matched HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1 alleles between donor and recipient (10/10 matched) can be decreased by selection of unrelated donors who also match for HLA-DPB1; however, such donors are difficult to find. Classification of HLA-DPB1 mismatches based on T-cell-epitope groups could identify mismatches that might be tolerated (permissive) and those that would increase risks (non-permissive) after transplantation. We did a retrospective study to compare outcomes between permissive and non-permissive HLA-DPB1 mismatches in unrelated-donor haemopoietic-cell transplantation. METHODS: HLA and clinical data for unrelated-donor [corrected] transplantations submitted to the International Histocompatibility Working Group in haemopoietic-cell transplantation were analysed retrospectively. HLA-DPB1 T-cell-epitope groups were assigned according to a functional algorithm based on alloreactive T-cell crossreactivity patterns. Recipients and unrelated donors matching status were classified as HLA-DPB1 match, non-permissive HLA-DPB1 mismatch (those with mismatched T-cell-epitope groups), or permissive HLA-DPB1 mismatch (those with matched T-cell-epitope groups). The clinical outcomes assessed were overall mortality, non-relapse mortality, relapse, and severe (grade 3-4) acute graft-versus-host disease (aGvHD). FINDINGS: Of 8539 transplantations, 5428 (64%) were matched for ten of ten HLA alleles (HLA 10/10 matched) and 3111 (36%) for nine of ten alleles (HLA 9/10 matched). Of the group overall, 1719 (20%) were HLA-DPB1 matches, 2670 (31%) non-permissive HLA-DPB1 mismatches, and 4150 (49%) permissive HLA-DPB1 mismatches. In HLA 10/10-matched transplantations, non-permissive mismatches were associated with a significantly increased risk of overall mortality (hazard ratio [HR] 1·15, 95% CI 1·05-1·25; p=0·002), non-relapse mortality (1·28, 1·14-1·42; p<0·0001), and severe aGvHD (odds ratio [OR] 1·31, 95% CI 1·11-1·54; p=0·001), but not relapse (HR 0·89, 95% CI 0·77-1·02; p=0·10), compared with permissive mismatches. There were significant differences between permissive HLA-DPB1 mismatches and HLA-DPB1 matches in terms of non-relapse mortality (0·86, 0·75-0·98; p=0·03) and relapse (1·34, 1·17-1·54; p<0·0001), but not for overall mortality (0·96, 0·87-1·06; p=0·40) or aGvHD (OR 0·84, 95% CI 0·69-1·03; p=0·09). In the HLA 9/10 matched population, non-permissive HLA-DPB1 mismatches also increased the risk of overall mortality (HR 1·10, 95% CI 1·00-1·22; p=0·06), non-relapse mortality (1·19, 1·05-1·36; p=0·007), and severe aGvHD (OR 1·37, 95% CI 1·13-1·66; p=0·002) compared with permissive mismatches, but the risk of relapse was the same in both groups (HR 0·93, 95% CI 0·78-1·11; p=0·44). Outcomes for HLA 10/10-matched transplantations with non-permissive HLA-DPB1 mismatches did not differ substantially from those for HLA 9/10-matched transplantations with permissive HLA-DPB1 mismatches or HLA-DPB1 matches. INTERPRETATION: T-cell-epitope matching defines permissive and non-permissive HLA-DPB1 mismatches. Avoidance of an unrelated donor with a non-permissive T-cell-epitope mismatch at HLA-DPB1 might provide a practical clinical strategy for lowering the risks of mortality after unrelated-donor haemopoietic-cell transplantation. FUNDING: National Institutes of Health; Associazione Italiana per la Ricerca sul Cancro; Telethon Foundation; Italian Ministry of Health; Cariplo Foundation; National Cancer Institute; National Heart, Lung and Blood Institute; National Institute of Allergy and Infectious Diseases; Office of Naval Research; IRGHET Paris; Swedish Cancer Society; Children's Cancer Foundation; Swedish Research Council; Cancer Society in Stockholm; Karolinska Institutet; and Leukemia and Lymphoma Society.
Asunto(s)
Epítopos de Linfocito T/inmunología , Cadenas beta de HLA-DP/genética , Cadenas beta de HLA-DP/inmunología , Histocompatibilidad/inmunología , Epítopos de Linfocito T/genética , Cadenas beta de HLA-DP/clasificación , Trasplante de Células Madre Hematopoyéticas/métodos , Histocompatibilidad/genética , Prueba de Histocompatibilidad , Humanos , Estudios Retrospectivos , Trasplante , Resultado del Tratamiento , Donante no EmparentadoRESUMEN
The success of hematopoietic cell transplantation from an unrelated donor depends in part on the degree of Human Histocompatibility Leukocyte Antigen (HLA) matching between donor and patient. We present a structure-based analysis of HLA mismatching, focusing on individual amino acid mismatches and their effect on peptide binding specificity. Using molecular modeling simulations of HLA-peptide interactions, we find evidence that amino acid mismatches predicted to perturb peptide binding specificity are associated with higher risk of mortality in a large and diverse dataset of patient-donor pairs assembled by the International Histocompatibility Working Group in Hematopoietic Cell Transplantation consortium. This analysis may represent a first step toward sequence-based prediction of relative risk for HLA allele mismatches.
RESUMEN
BACKGROUND: Granulocyte antibodies have been implicated in allo- and autoimmune neutropenia and in transfusion reactions. STUDY DESIGN AND METHODS: Fifty-one sera from suspected alloimmune neutropenia or transfusion-related acute lung injury (TRALI) and 40 sera from suspected autoimmune neutropenia were tested for granulocyte antibodies using LABScreen MULTI (One Lambda, Inc.), compared with classical tests (flow cytometry [FC] and granulocyte agglutination [GAT] followed by monoclonal antibody-specific immobilization of granulocyte antigens [MAIGA]). RESULTS: In alloimmune situations, 48 sera were concordant (94%), two sera positive for HNA with LABScreen MULTI were negative by FC/GAT and/or MAIGA, and one serum sample negative for HNA with LABScreen MULTI was positive by classical tests. In autoimmune neutropenia, 30 sera were concordant (75%), four sera positive for HNA with LABScreen MULTI were negative by FC/GAT and/or MAIGA, and six sera negative for HNA with LABScreen MULTI were positive by FC/GAT and/or MAIGA. For detection of autoantibodies, the LABScreen MULTI was less concordant. However, with the exception of one case, the discrepancies were observed in sera that did not show a clear specificity. CONCLUSIONS: LABScreen MULTI correlated well with our classical methods for HNA-1 and HNA-2a antibody screening. It can be used for screening blood donors or patients suspected of TRALI, but GAT is still needed for HNA-3a antibody screening.
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Anticuerpos/análisis , Granulocitos/inmunología , Separación Inmunomagnética/métodos , Tamizaje Masivo/métodos , Lesión Pulmonar Aguda/sangre , Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/inmunología , Anticuerpos/sangre , Anticuerpos/inmunología , Autoanticuerpos/análisis , Autoanticuerpos/inmunología , Humanos , Inmunoensayo/métodos , Inmunoensayo/normas , Separación Inmunomagnética/normas , Recién Nacido , Isoantígenos/análisis , Isoantígenos/inmunología , Tamizaje Masivo/normas , Neutropenia/sangre , Neutropenia/congénito , Neutropenia/inmunología , Valores de Referencia , Pruebas Serológicas/métodos , Pruebas Serológicas/normas , Trombocitopenia Neonatal Aloinmune/sangre , Trombocitopenia Neonatal Aloinmune/inmunología , Reacción a la TransfusiónRESUMEN
Given their antileukemic activity, natural killer (NK) cells can alter the outcome of hematopoietic stem cell transplantation (HSCT). The physiologic functions of NK cells are regulated by the interaction of killer immunoglobulin-like receptors (KIR) with specific HLA class I ligands. In the literature, different models based on HLA class I and/or KIR donor (D)/recipient (R) gene disparities are considered as predictors of NK cell alloreactivity. In this retrospective and multicentric French study, we analyzed the clinical impact of the different NK-alloreactivity models in 264 patients who underwent T repleted unrelated HSCT. First, we did not observe that the "KIR ligand-ligand" model had a significant clinical impact on unrelated HSCT outcome, whereas the "missing KIR ligand" model had a significant but limited effect on unrelated HSCT, because only the absence of C1 ligand in patients with myelogenous diseases was associated with a decreased overall survival (OS) (hazard ratio=2.17, P=.005). The "KIR receptor-receptor" and the "KIR receptor-ligand" models seemed the most capable of predicting NK alloreactivity because they had a significant impact on acute graft-versus-host disease (aGVHD) occurrence, OS, and relapse incidence in D/R unrelated pairs. In particular, KIR3DL1 gene mismatches in the GVH direction (D(+)R(-)) and the D KIR3DL1(+)/3DS1(+) and R Bw4(-) combination were respectively correlated with the lowest OS in HLA identical pairs (HR=1.99, P =.02) and the highest incidence of relapse in HLA nonidentical D/R unrelated pairs (HR=4.72, P =.03). Overall, our results suggest a detrimental effect of KIR3DL1(+)/3DS1(+) donor NK cells transplanted into HLA-Bw4(-) patients in the absence of an educational process via KIR3DL1/HLA-Bw4 interactions.
Asunto(s)
Antígenos HLA-B/análisis , Trasplante de Células Madre Hematopoyéticas , Células Asesinas Naturales/inmunología , Donadores Vivos , Receptores KIR3DL1/genética , Receptores KIR3DS1/genética , Adolescente , Adulto , Biomarcadores , Enfermedades de la Médula Ósea/cirugía , Niño , Preescolar , Femenino , Estudios de Seguimiento , Neoplasias Hematológicas/cirugía , Histocompatibilidad , Humanos , Lactante , Ligandos , Masculino , Persona de Mediana Edad , Modelos Inmunológicos , Pronóstico , Recurrencia , Estudios Retrospectivos , Análisis de Supervivencia , Trasplante Homólogo/inmunología , Resultado del Tratamiento , Adulto JovenRESUMEN
Natural killer (NK) cells are key components of the innate anti-viral and anti-tumour immune responses. NK cell function is regulated by the interaction of killer cell immunoglobulin-like receptors (KIR) with human leucocyte antigen (HLA) class I molecules. In this study, we report on the generation of KIR-specific antibodies allowing for discrimination between activating and inhibitory KIR. For this purpose, BALB/c mice were immunized with human KIR2DS2 recombinant protein. The precise specificity of KIR2DS2-specific clones was determined on KIR-transfected BW cells and KIR-genotyped NK cells. When used in combination with EB6 (KIR2DL1/2DS1) or GL183 (KIR2DL2/2DL3/2DS2), two KIR-specific monoclonal antibodies (mAbs), 8C11 (specific for KIR2DL1/2DL2/2DL3/2DS2) and 1F12 (specific for KIR2DL3/2DS2), discriminated activating KIR2DS1 (8C11(-) EB6(+)) from inhibitory KIR2DL1 (8C11(+) GL183(-)) and KIR2DL2 (1F12(-) GL183(+)), while excluding the main HLA-Cw-specific KIR. Using these mAbs, KIR2DS1 was shown to be expressed on the surface of NK cells from all individuals genotyped as KIR2DS1(+) (n = 23). Moreover, KIR2DS1 and KIR2DL1 were independently expressed on NK cells. We also determined the amino acid position recognized by the 8C11 and 1F12 mAbs, which revealed that some KIR2DL1 allele-encoded proteins are not recognized by 8C11. Because most available anti-KIR mAbs recognize both inhibitory and activating forms of KIR, these newly characterized antibodies should help assess the expression of activating and inhibitory KIR and their functional relevance to NK biology.
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Anticuerpos Monoclonales/inmunología , Células Asesinas Naturales/inmunología , Subgrupos Linfocitarios/inmunología , Receptores KIR/inmunología , Adulto , Animales , Especificidad de Anticuerpos , Secuencia de Bases , Genotipo , Humanos , Hibridomas , Inmunización , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Receptores KIR/genética , Receptores KIR2DL1/inmunología , Receptores KIR2DL3/inmunología , Alineación de SecuenciaRESUMEN
Recently, the Z27 mAb was shown to recognize the NK cell-activating receptor KIR3DS1, and several genetic studies suggest that the most probable ligands of KIR3DS1 are HLA class I molecules with the Bw4 motif. Despite these findings, the attempts to establish a functional interaction between KIR3DS1 and its potential ligand have been unsuccessful. Here, we study the proliferation and cytotoxicity of KIR3DS1(+) NK cells, compared with KIR3DL1(+) NK cells, according to the Bw4(+) or Bw4(-) allogeneic environment. Our results show for the first time that KIR3DS1 expression on NK cells can be induced after exposure to stimulator cells (221, K562, EBV-B cell lines, and B cells), polyinosinic-polycytidylic acid, IL-15, or IL-2. Furthermore, whereas KIR3DL1(+) NK cell proliferation and cytotoxicity were inhibited in a Bw4(+) but not a Bw4(-) context, KIR3DS1(+) NK cell functions were not influenced by the presence of Bw4 on target cells. Nevertheless, despite the absence of demonstrated regulation of KIR3DS1(+) NK cell functions by HLA-Bw4 molecules, we found a higher KIR3DS1(+) NK cell frequency and higher levels of KIR3DS1 expression in Bw4(+) compared with Bw4(-) individuals. Altogether, these results suggest that KIR3DS1 does not recognize HLA-Bw4 molecules in a physiological context, and they highlight the induced expression of KIR3DS1 observed on stimulated NK cells and the higher frequency of KIR3DS1(+) NK cells in Bw4(+) individuals. Because a protective KIR3DS1-Bw4 association has been reported in viral infections, our results further the understanding of the role of KIR3DS1(+) NK cells in controlling viral infections.
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Antígenos HLA-B/fisiología , Células T Asesinas Naturales/inmunología , Receptores KIR3DL1/análisis , Receptores KIR3DS1/análisis , Proliferación Celular , Citotoxicidad Inmunológica , Regulación de la Expresión Génica/inmunología , Humanos , Células K562 , Activación de Linfocitos , Células T Asesinas Naturales/citología , Subgrupos de Linfocitos TRESUMEN
NK-cell function is regulated by a balance between inhibitory and activating killer cell immunoglobulin-like receptors (KIR) that specifically recognize HLA class I molecules. Using KIR-specific mAb to discriminate between KIR2DS1 and KIR2DL1 receptors, we show that KIR2DS1(+) NK cells are C2-alloreactive only from C2(-) individuals. Moreover, using an in vitro model of NK-cell expansion, we show here that the frequency of KIR2DL1(+) NK cells is significantly higher in the absence of C2 ligand on stimulator EBV-B cells than in its presence. This observation was made regardless of the presence or absence of the autologous C2 ligand, suggesting that the C2(-) EBV-B stimulator cells used in this in vitro model could activate unlicensed KIR2DL1(+) NK cells. In the case of KIR2DL1(+)/S1(+) genotyped individuals, KIR2DS1(+) NK-cell frequency was increased after stimulation with C2(+) compared with C2(-) stimulator B cells, but only from C2(-) individuals. Altogether, these data highlight the C2 alloreactivity of KIR2DS1(+) NK cells that is only observed in C2(-) individuals. These results provide new insights into the way in which NK KIR cell expansion might be regulated in an allogeneic environment.
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Autoinmunidad/inmunología , Antígenos HLA/inmunología , Células Asesinas Naturales/inmunología , Receptores KIR/inmunología , Diferenciación Celular/inmunología , Células Cultivadas , Genotipo , Herpesvirus Humano 4/inmunología , Humanos , Células Asesinas Naturales/citología , Ligandos , Unión ProteicaAsunto(s)
Anticuerpos/química , Diabetes Mellitus/terapia , Antígenos HLA/inmunología , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/citología , Ensayos Clínicos como Asunto , Estudios de Cohortes , Antígenos HLA/química , Humanos , Inmunofenotipificación , Inmunosupresores/uso terapéutico , Insulina/metabolismoRESUMEN
BACKGROUND: Human platelet antigen (HPA)-1a fetomaternal alloimmune thrombocytopenia, responsible in the most severe cases for fetal or neonatal intracranial hemorrhages leading to death or survival with neurologic sequelae, was shown to be restricted to the human leukocyte antigen (HLA) Class II DRB3*0101-encoded molecule. Whereas more than 90 percent of alloimmunized mothers display the DRB3*0101 allele, the positive predictive value of the presence of DRB3*0101 is only 35 percent. Additional genetic risk factors may exist of which elucidation could improve the undertaking of incompatible pregnancies in at-risk families, encouraging an antenatal screening. Interactions of killer immunoglobulinlike receptors (KIRs) on maternal decidual NK cells with HLA-Cw molecules on fetal trophoblasts were reported as one of the mechanisms involved in the fetomaternal tolerance during pregnancy. STUDY DESIGN AND METHODS: Genotyping was performed of 16 KIR genes in HPA-1a-negative/DRB3*0101-positive alloimmunized mothers and in HPA-1a-negative/DRB3*0101-positive nonimmunized mothers as well as HLA-Cw genotyping in thrombocytopenic children and their nonaffected siblings. RESULTS: No particular KIR genes or KIR genotypes were observed in the alloimmunized or nonimmunized mothers. Distribution of HLA-Cw genes in affected infants and nonaffected siblings did not reveal any HLA-Cw specificity associated with triggering or modulation of the HPA-1a alloimmunization. No maternal KIR/fetal HLA-Cw combinations were demonstrated in association with a detrimental or a protective effect on the HPA-1a alloimmunization. CONCLUSION: Maternal KIR/fetal HLA-Cw gene combinations that are involved in the fetomaternal tolerance do not appear to play a role in the HPA-1a alloimmunization.
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Antígenos de Plaqueta Humana/inmunología , Antígenos HLA/genética , Receptores KIR/genética , Femenino , Genotipo , Antígenos HLA/inmunología , Humanos , Integrina beta3 , Isoanticuerpos/inmunología , Intercambio Materno-Fetal , Embarazo , Receptores KIR/inmunologíaRESUMEN
HLA matching between the donor and recipient improves the success of unrelated hematopoietic stem cell transplantation (HSCT). Because many patients in need of an unrelated transplant have only donors with mismatch, information is needed to evaluate the limits of HLA mismatching. We examined the association of survival, acute graft-versus-host disease (aGVHD) and relapse with HLA-A, -B, -C, -DRB, -DQB1, and -DPB1 mismatching in 334 patients coming from 12 French transplant centers and who received a non-T cell-depleted bone marrow graft from an unrelated donor. All patients were prepared with the use of myeloablative conditioning regimens. Our analyses demonstrate negative effects of HLA mismatching for either HLA-A, -B, -C, -DRB1, or -DQB1 loci on survival. Multivariate Cox analyses showed that a single mismatch was associated with a significant decrement in survival (P=.046, hazard ratio [HR]=1.41, confidence interval [CI] 95% 1.1-1.98). The presence of multiple mismatches was worse for survival (P=.003, HR=1.91, CI 95% 1.26-2.91) and severe aGVHD (grade III-IV) (P=.002, HR=2.51, CI95% 1.41-4.46). The cumulative incidences of aGVHD and relapse in those HLA-A, -B, -C, -DRB1, and -DQB1 identical pairs with 2, 1, or 0 DPB1 incompatibilities were 63%, 50%, and 51%, and 12%, 27%, and 20%, respectively, but these differences were not statistically significant. Similar differences of aGVHD and relapse, but not statistically significant, were observed in those HLA-A, -B, -C, -DRB1, and -DQB1 identical pairs with DPB1 disparities classified into permissive or nonpermissive mismatches according to Zino's classification based on a hierarchy of the immunogenicity of the HLA-DP molecules. "Missing killer cell immunoglobulin-like receptor (KIR) ligand" evaluated on the presence of HLA-C1, -C2, and Bw4 groups in the recipients was not associated with aGVHD, survival, and relapse in this cohort of non-T cell-depleted HSCT.
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Enfermedad Injerto contra Huésped/inmunología , Antígenos HLA/inmunología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Prueba de Histocompatibilidad , Adolescente , Adulto , Niño , Preescolar , Estudios de Cohortes , Femenino , Antígenos HLA/efectos adversos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Medición de Riesgo , Análisis de SupervivenciaRESUMEN
Despite the progress in renal transplantation, acute rejection and graft failure still occur and chronic rejection continues to be the main problem in long-term allograft survival. Although kidney transplant rejection has been linked to anti-HLA antibodies, not all patients with failed kidney transplants have anti-HLA antibodies, indicating that other loci may be involved. Sera of 63 patients who experienced kidney rejection were compared against sera of 82 patients with functioning transplants. Sera were examined for IgG and IgM anti-HLA Class I and II antibodies. They were also tested by cytotoxicity against panels of 26 endothelial cell lines, 8 MHC class I chain-related gene A (MICA) recombinant cell lines, and 28 B lymphoblast cell lines. Among patients whose transplants failed, 65% had anti-HLA antibodies compared with 45% of those with functioning kidneys (p < 0.05). Similarly, among those whose transplants failed, 41% had anti-endothelial cell antibodies in contrast to 22% in functioning patients (p < 0.05). Among patients whose grafts failed, 52% had anti-MICA antibodies versus 21% of those with functioning grafts (p < 0.001). Eleven patients with failed grafts and 32 with functioning grafts were negative for all of the above. However, 6 of the former and 7 of the latter showed positive cytotoxicity against B lymphoblasts (p < 0.05). Taking all antibodies together, 92% of patients with graft failure had antibodies as opposed to 70% of patients with functioning grafts (p < 0.001). We postulate that antibodies against HLA, MICA, endothelial cells, and B lymphoblasts could be independently involved in the slow process of chronic graft failure.
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Rechazo de Injerto/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Trasplante de Riñón/inmunología , Linfocitos B/inmunología , Línea Celular , Citotoxicidad Inmunológica , Células Endoteliales/inmunología , Citometría de Flujo , Rechazo de Injerto/sangre , Antígenos HLA/inmunología , Humanos , Estudios Retrospectivos , Células Madre/inmunologíaRESUMEN
Recurrent malignancy remains a significant complication after allogeneic hematopoietic cell transplantation (HCT). Efforts to decrease relapse have included donor lymphocyte infusion to stimulate donor anti-recipient T-cell allorecognition of major and minor histocompatibility differences. Recently, alloreactive effects of donor natural killer cell-mediated inhibitory killer immunoglobulin-like receptor (KIR) recognition of recipient HLA-C and -B ligands have been described. We examined KIR ligand effects on risk of relapse in 1770 patients undergoing myeloablative T-replete HCT from HLA-matched or -mismatched unrelated donors for the treatment of myeloid and lymphoid leukemias. KIR ligands defined by HLA-B and -C genotypes were used to determine donor-recipient ligand incompatibility or recipient lack of KIR ligand. Among HLA-mismatched transplantations, recipient homozygosity for HLA-B or -C KIR epitopes predicted lack of KIR ligand and was associated with a decreased hazard of relapse (hazard ratio, 0.61; 95% confidence interval, .043-0.85; P = .004). Absence of HLA-C group 2 or HLA-Bw4 KIR ligands was associated with lower hazards of relapse (hazard ratio, 0.47; 95% confidence interval, 0.28-0.79, P = .004; hazard ratio, 0.56; 95% confidence interval, 0.33-0.97; P = .04, respectively). The decrease in hazard of relapse in patients with acute myelogenous leukemia was similar to that in patients with chronic myelogenous leukemia and acute lymphoblastic leukemia (P = .95). Recipient homozygosity for HLA-B or -C epitopes that define KIR ligands is likely to be a predictive factor for leukemia relapse after myeloablative HCT from HLA-mismatched unrelated donors. This effect was not observed in HLA-identical unrelated transplants.
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Antígenos HLA-B/genética , Neoplasias Hematológicas/genética , Trasplante de Células Madre Hematopoyéticas , Isoantígenos/genética , Donadores Vivos , Transfusión de Linfocitos , Supervivencia sin Enfermedad , Epítopos/genética , Epítopos/inmunología , Femenino , Estudios de Seguimiento , Antígenos HLA-B/inmunología , Antígenos HLA-C/genética , Antígenos HLA-C/inmunología , Neoplasias Hematológicas/inmunología , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Isoantígenos/inmunología , Células Asesinas Naturales/inmunología , Ligandos , Transfusión de Linfocitos/mortalidad , Masculino , Receptores Inmunológicos/agonistas , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , Receptores KIR , Recurrencia , Factores de Riesgo , Tasa de Supervivencia , Linfocitos T/inmunología , Trasplante HomólogoRESUMEN
Although the key role of MHC-restricted T lymphocytes in hematopoietic stem cell transplantation (HSCT) has been known for a long time, recent data have focused on complementary or alternative effector cell populations, and in particular on NK cells. Spontaneously generated NK cell alloreactivity from stem cell grafts involves specific interactions between NK receptors, including killer immunoglobulin-like receptors (KIRs) and their MHC class I ligands. The combined effects of HLA and KIR polymorphic genes might explain discrepancies in the impact of donor-recipient matching observed in HSCT.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Células Asesinas Naturales/inmunología , Receptores Inmunológicos/genética , Animales , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Prueba de Histocompatibilidad , Humanos , Receptores Inmunológicos/inmunología , Receptores KIRRESUMEN
The involvement of immunologic and nonimmunologic events in long-term kidney allograft failure is difficult to assess. The development of HLA antibodies after transplantation is the witness of ongoing reactivity against the transplant, and several studies have suggested that the presence of HLA antibodies correlates with poor graft survival. However, they have not discriminated between donor-specific (DS) and non-specific (NDS) antibodies. A total of 1229 recipients of a kidney graft, transplanted between 1972 and 2002, who had over a 5-yr period a prospective annual screening for HLA antibodies with a combination of ELISA, complement-dependent cytotoxicity, and flow cytometry tests were investigated; in 543 of them, the screening was complete from transplantation to the fifth year postgrafting. Correlations were established between the presence and the specificity of the antibodies and clinical parameters. A total of 5.5% of the patients had DS, 11.3% had NDS, and 83% had no HLA antibodies after transplantation. NDS antibodies appeared earlier (1 to 5 yr posttransplantation) than DS antibodies (5 to 10 yr). In multivariate analysis, HLA-DR matching, pretransplantation immunization, and acute rejection were significantly associated with the development of both DS and NDS antibodies and also of DS versus NDS antibodies. The presence of either DS or NDS antibodies significantly correlated with lower graft survival, poor transplant function, and proteinuria. Screening of HLA antibodies posttransplantation could be a good tool for the follow-up of patients who receive a kidney transplant and allow immunosuppression to be tailored.
Asunto(s)
Antígenos HLA/inmunología , Isoanticuerpos/sangre , Trasplante de Riñón/inmunología , Donantes de Tejidos , Adulto , Especificidad de Anticuerpos , Femenino , Estudios de Seguimiento , Rechazo de Injerto/etiología , Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Humanos , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
Natural killer (NK) cell alloreactivity observed during stem cell transplantation (SCT) can be either beneficial (graft-versus-leukemia effect) or detrimental to the host (graft-versus-host disease). Killer immunoglobulin-like receptors (KIRs), expressed on NK and CD8 memory T cells, are regulated at a posttranscriptional level and, because there are currently no KIR-specific antibodies available, the analysis of these receptors remains elusive. To better define the role of cells expressing KIR after SCT, we studied KIR transcript repertoires in 29 grafted patients who received myeloablative or nonmyeloablative regimens. We restricted our analysis to 3DL1, 3DL2, 2DL4, 2DS3, and 2DS4 KIR transcripts 6 months after SCT. Absolute counts of NK and CD8 T cells were determined by flow cytometry, and KIR transcripts were quantified by real-time reverse transcription polymerase chain reaction at days 14, 28, 60, 100, and 180 after transplantation. Three groups of patients were identified. Groups I and III were characterized by the absence or a delayed appearance of KIR transcripts, which correlated with the highest risk of acute graft-versus-host disease (aGvHD). In contrast, in group II, a significant transcript peak was observed early, and only one patient suffered from aGvHD (p = 0.025). Thus determining the kinetics of KIR transcription should make it possible to identify transplanted patients at a high risk of developing aGvHD.
Asunto(s)
Trasplante de Médula Ósea/inmunología , Enfermedad Injerto contra Huésped/inmunología , Células Asesinas Naturales/inmunología , Receptores Inmunológicos/genética , Trasplante Homólogo/inmunología , Adolescente , Adulto , Recuento de Células Sanguíneas , Linfocitos T CD8-positivos/citología , Membrana Celular/metabolismo , Femenino , Expresión Génica/genética , Expresión Génica/inmunología , Genotipo , Humanos , Hipoxantina Fosforribosiltransferasa/genética , Células Asesinas Naturales/citología , Células Asesinas Naturales/metabolismo , Cinética , Masculino , Persona de Mediana Edad , Receptores Inmunológicos/inmunología , Receptores Inmunológicos/metabolismo , Receptores KIR , Receptores KIR2DL4 , Receptores KIR3DL1 , Receptores KIR3DL2 , Transcripción Genética/genética , Transcripción Genética/inmunología , Acondicionamiento PretrasplanteRESUMEN
BACKGROUND: Second kidney transplantations have a roughly similar clinical outcome to first transplantations. Nevertheless, the effect of the presence of the first, nonfunctional transplant at the time of the second transplantation may also influence its outcome and has not yet been specifically studied. METHODS: We analyzed the effect of the presence of a first graft on the outcome of a second graft in a rodent allograft model and in a cohort of 240 human second kidney allograft recipients. RESULTS: In rodents, 100 days subsequent to the rejection of the first graft, we observed an increase in blood but not spleen CD4(+)CD25(+) T cells, whereas no differences were observed in transcriptional patterns. Adoptive transfer of day 100 splenocytes did not prolong graft survival. Moreover, the presence of a first rejected graft does not prolong the survival of a second graft performed at a later date. In the human context, a higher incidence of patients with anti-HLA immunization and a higher % of PRA were observed in retransplant recipients with primary allograft nephrectomy. Despite a relatively low statistical power, our data do not suggest significant differences in graft outcome between recipients of second transplants with primary allograft nephrectomy and those without. CONCLUSION: Collectively, the data from both an experimental model and a large cohort of human recipients of a second graft do not suggest a beneficial effect of the presence of a first rejected graft at the time of a second transplantation.
Asunto(s)
Trasplante de Riñón , Adolescente , Adulto , Anciano , Animales , Femenino , Rechazo de Injerto , Supervivencia de Injerto , Prueba de Histocompatibilidad , Humanos , Isoanticuerpos/sangre , Trasplante de Riñón/inmunología , Masculino , Persona de Mediana Edad , Fenotipo , Ratas , Ratas Endogámicas Lew , Resultado del TratamientoRESUMEN
BACKGROUND: The aim of the present study was to assess long-term survival of cadaveric second kidney allografts performed in our center and to determine risk factors predictive of long-term graft outcome. METHODS: Of 1704 kidney transplantations performed between January 1985 and March 1998, 233 were second grafts. The majority of the recipients were sensitized. All patients were treated with the same quadruple immunosuppressive regimen. RESULTS: Kaplan-Meier analysis documented graft survival of 89% at 1 year, 76% at 5 years, and 53% at 10 years. Graft survival was similar for second and primary kidney transplants performed during the same period of time. When long-term second graft survival was examined, only two risk factors were found to be significant: (1) the degree of human leukocyte antigen (HLA) DR mismatch (MM) and (2) the number of acute rejection episodes. Multivariate analysis of several pre- and posttransplant variables also confirmed the importance of HLA MM (DR> A), but also, identified serum creatinine at 12 months as the most significant predictor of graft survival. In addition, the Cox proportional hazards model revealed that only the year of transplantation had an independent significant effect on acute rejection occurrence (RR = 0.591, 95%CI 0.437 to 0.801, P < 0.0007). Indeed, the incidence of acute rejection was found to decrease over time (44% of patients experienced at least one episode of acute rejection before 1990 vs. 17% after 1990). CONCLUSION: Finally, second graft long-term outcome shows an improved evolution according to the time period resulting from a strong decrease in acute rejection incidence and the impact of creatinine at 12 months.
Asunto(s)
Supervivencia de Injerto , Fallo Renal Crónico/mortalidad , Trasplante de Riñón/mortalidad , Reoperación/mortalidad , Enfermedad Aguda , Adulto , Cadáver , Femenino , Rechazo de Injerto/inmunología , Rechazo de Injerto/mortalidad , Humanos , Terapia de Inmunosupresión , Riñón/fisiología , Fallo Renal Crónico/inmunología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Factores de Riesgo , Análisis de SupervivenciaRESUMEN
The vascular endothelium of transplanted organs represents an important target for allograft-directed immune responses. Although HLA antigens expressed on graft endothelial cells (EC) can become targets of the host immune response, the role of other, non-HLA-encoded EC antigens has been proposed but is still unclear. The aim of this study was to investigate the presence of and to characterize anti-EC antibodies (AECA) in 57 kidney transplant recipients according to their HLA-immunization status. Flow cytometry in pretransplant sera was used to detect AECA reactive with surface antigens on ABO and HLA-typed primary cultures of arterial ECs, stimulated or not with tumor necrosis factor-alpha (TNFalpha) or interferon-gamma (IFNgamma). FACS analysis revealed the presence of AECA in 47% of HLA-sensitized (PRA = 10%: mostly IgG) vs. 16.0% in nonsensitized patients (PRA < 10%) (p < 0.02). No significant correlation was found between the presence of AECA and acute rejection occurrence and graft outcome. Non-HLA reactive AECA are directed against TNFalpha- and IFNgamma-inducible membrane molecule(s), and react with two predominant antigens of approximately 35 kDa and approximately 50 kDa expressed on ECs but not on B cells. Binding of AECA decreases in vitro EC viability by 50-60% by promoting EC apoptosis, as demonstrated by DNA fragmentation assays.