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1.
Sci Transl Med ; 15(717): eadf4287, 2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37820009

RESUMO

Immune cell-based therapies are promising strategies to facilitate immunosuppression withdrawal after organ transplantation. Regulatory dendritic cells (DCreg) are innate immune cells that down-regulate alloimmune responses in preclinical models. Here, we performed clinical monitoring and comprehensive assessment of peripheral and allograft tissue immune cell populations in DCreg-infused live-donor liver transplant (LDLT) recipients up to 12 months (M) after transplant. Thirteen patients were given a single infusion of donor-derived DCreg 1 week before transplant (STUDY) and were compared with 40 propensity-matched standard-of-care (SOC) patients. Donor-derived DCreg infusion was well tolerated in all STUDY patients. There were no differences in postoperative complications or biopsy-confirmed acute rejection compared with SOC patients up to 12M. DCreg administration was associated with lower frequencies of effector T-bet+Eomes+CD8+ T cells and CD16bright natural killer (NK) cells and an increase in putative tolerogenic CD141+CD163+ DCs compared with SOC at 12M. Antidonor proliferative capacity of interferon-γ+ (IFN-γ+) CD4+ and CD8+ T cells was lower compared with antithird party responses in STUDY participants, but not in SOC patients, at 12M. In addition, lower circulating concentrations of interleukin-12p40 (IL-12p40), IFN-γ, and CXCL10 were detected in STUDY participants compared with SOC patients at 12M. Analysis of 12M allograft biopsies revealed lower frequencies of graft-infiltrating CD8+ T cells, as well as attenuation of cytolytic TH1 effector genes and pathways among intragraft CD8+ T cells and NK cells, in DCreg-infused patients. These reductions may be conducive to reduced dependence on immunosuppressive drug therapy or immunosuppression withdrawal.


Assuntos
Linfócitos T CD8-Positivos , Transplante de Fígado , Humanos , Células Dendríticas/metabolismo , Doadores Vivos , Células Matadoras Naturais , Interferon gama/metabolismo , Rejeição de Enxerto
2.
Kidney Int ; 104(4): 707-723, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37220805

RESUMO

The role of Natural killer (NK) cells during kidney allograft antibody-mediated rejection (ABMR) is increasingly recognized, but an in-depth characterization of mechanisms that contribute to such immune response is still under investigation. Here, we characterized phenotypic, functional, and transcriptomic profiles of peripheral blood circulating and allograft infiltrating CD56dimCD16bright NK cells during anti-HLA donor-specific antibody (DSA)+ ABMR. Cross-sectional analyses performed in 71 kidney transplant recipients identified a unique phenotypic circulating CD56dimCD16bright NK cell cluster expanded in DSA+ ABMR. This cluster co-expressed high levels of the interleukin-21 Receptor (IL-21R); Type-1 transcription factors T-bet and EOMES, CD160 and natural killer group 2D cytotoxic and activating co-stimulatory receptors. CD160+ IL-21R+ NK cells correlated with elevated plasma IL-21, Ki-67+ ICOS+ (CD278) IL-21-producing circulating T follicular helper cells, enhanced Type-1 pro-inflammatory cytokines, NK cell cytotoxicity, worse microvascular inflammation and graft loss. Single-cell transcriptomic analysis of circulating NK cells delineated an expanded cluster in DSA+ ABMR characterized by elevated pro-inflammatory/cytotoxic pathways, IL-21/STAT3 signaling, and leukocyte trans-endothelial migration pathways. Infiltration of CD160+ IL-21R+ NK cells with similar transcriptomic profile was detected in DSA+ ABMR allograft biopsies, potentially contributing to allograft injury. Thus, the IL-21/IL-21R axis, linking adaptive and innate humoral allo-immunity, or NK cells may represent appealing immunotherapy targets in DSA+ ABMR.


Assuntos
Transplante de Rim , Transplante de Rim/efeitos adversos , Estudos Transversais , Células Matadoras Naturais , Anticorpos , Rim , Aloenxertos , Rejeição de Enxerto
3.
Am J Transplant ; 23(8): 1145-1158, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37187296

RESUMO

Chronic Epstein-Barr virus (EBV) infection after pediatric organ transplantation (Tx) accounts for significant morbidity and mortality. The risk of complications, such as posttransplant lymphoproliferative disorders, in high viral load (HVL) carriers is the highest in heart Tx recipients. However, the immunologic signatures of such a risk have been insufficiently defined. Here, we assessed the phenotypic, functional, and transcriptomic profiles of peripheral blood CD8+/CD4+ T cells, including EBV-specific T cells, in 77 pediatric heart, kidney, and liver Tx recipients and established the relationship between memory differentiation and progression toward exhaustion. Unlike kidney and liver HVL carriers, heart HVL carriers displayed distinct CD8+ T cells with (1) up-regulation of interleukin-21R, (2) decreased naive phenotype and altered memory differentiation, (3) accumulation of terminally exhausted (TEX PD-1+T-bet-Eomes+) and decrease of functional precursors of exhausted (TPEX PD-1intT-bet+) effector subsets, and (4) transcriptomic signatures supporting the phenotypic changes. In addition, CD4+ T cells from heart HVL carriers displayed similar changes in naive and memory subsets, elevated Th1 follicular helper cells, and plasma interleukin-21, suggesting an alternative inflammatory mechanism that governs T cell responses in heart Tx recipients. These results may explain the different incidences of EBV complications and may help improve the risk stratification and clinical management of different types of Tx recipients.


Assuntos
Infecções por Vírus Epstein-Barr , Transplante de Fígado , Transtornos Linfoproliferativos , Humanos , Herpesvirus Humano 4 , Transplante de Fígado/efeitos adversos , Linfócitos T CD8-Positivos , Receptor de Morte Celular Programada 1 , Rim , Carga Viral , Transplantados
4.
Commun Biol ; 5(1): 634, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768564

RESUMO

T cells are endowed with the capacity to sense their environment including other T cells around them. They do so to set their numbers and activation thresholds. This form of regulation has been well-studied within a given T cell population - i.e., within the naïve or memory pool; however, less is known about the cross-talk between T cell subsets. Here, we tested whether memory T cells interact with and influence surrounding naïve T cells. We report that human naïve CD8 T cells (TN) undergo phenotypic and transcriptional changes in the presence of autologous activated-memory CD8 T cells (TMem). Following in vitro co-culture with activated central memory cells (TCM), ~3% of the TN acquired activation/memory canonical markers (CD45RO and CD95) in an MHC-I dependent-fashion. Using scRNA-seq, we also observed that ~3% of the TN acquired an activated/memory signature, while ~84% developed a unique activated transcriptional profile hybrid between naïve and activated memory. Pseudotime trajectory analysis provided further evidence that TN with an activated/memory or hybrid phenotype were derived from TN. Our data reveal a non-cytotoxic function of TMem with potential to activate autologous TN into the activated/memory pool. These findings may have implications for host-protection and autoimmunity that arises after vaccination, infection or transplantation.


Assuntos
Memória Imunológica , Células T de Memória , Linfócitos T CD8-Positivos , Humanos , Subpopulações de Linfócitos T
5.
Kidney Int ; 101(5): 1003-1016, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35090879

RESUMO

Although considerable advances have been made in understanding the cellular effector mechanisms responsible for donor-specific antibody generation leading to antibody-mediated rejection (ABMR), the identification of cellular regulators of such immune responses is lacking. To clarify this, we used high dimensional flow cytometry to concomitantly profile and track the two major subsets of regulatory lymphocytes in blood: T regulatory (TREG) and transitional B cells in a cohort of 96 kidney transplant recipients. Additionally, we established co-culture assays to address their respective capacity to suppress antibody responses in vitro. TREG and transitional B cells were found to be potent suppressors of T follicular helper-mediated B-cell differentiation into plasmablast and antibody generation. TREG and transitional B cells were both durably expanded in patients who did not develop donor-specific antibody post-transplant. However, patients who manifested donor-specific antibody and progressed to ABMR displayed a marked and persistent numerical reduction in TREG and transitional B cells. Strikingly, specific cell clusters expressing the transcription factor T-bet were selectively depleted in both TREG and transitional B-cell compartments in patients with ABMR. Importantly, the coordinated loss of these T-bet+CXCR5+TREG and T-bet+CD21- transitional B-cell clusters was correlated with increased and inflammatory donor specific antibody responses, more extensive microvascular inflammation and a higher rate of kidney allograft loss. Thus, our study identified coordinated and persistent defects in regulatory T- and B-cell responses in patients undergoing ABMR, which may contribute to their loss of humoral immune regulation, and warrant timely therapeutic interventions to replenish and sustain TREG and transitional B cells in these patients.


Assuntos
Transplante de Rim , Anticorpos , Linfócitos B , Rejeição de Enxerto/diagnóstico , Humanos , Transplante de Rim/efeitos adversos , Linfócitos T Reguladores , Doadores de Tecidos
6.
Trends Mol Med ; 28(3): 237-250, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35093288

RESUMO

Humoral alloimmunity of organ transplant recipient to donor can lead to antibody-mediated rejection (ABMR), causing thousands of organ transplants to fail each year worldwide. However, the mechanisms of adaptive immune cell responses at the basis of humoral alloimmunity have not been entirely understood. In this review, we discuss how recent investigations have uncovered the key contributions of T follicular helper (TFH) and B cells and their coordinated actions in driving donor-specific antibody generation and immune progression towards ABMR. We show how recognition of the role of TFH-B cell interactions may allow the elaboration of improved clinical strategies for immune monitoring and the identification of novel therapeutic targets to tackle ABMR that will ultimately improve organ transplant survival.


Assuntos
Rejeição de Enxerto , Transplante de Órgãos , Anticorpos , Sobrevivência de Enxerto , Humanos , Imunidade Humoral , Transplante de Órgãos/efeitos adversos
7.
Front Immunol ; 12: 705465, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262574

RESUMO

Liver allograft recipients are more likely to develop transplantation tolerance than those that receive other types of organ graft. Experimental studies suggest that immune cells and other non-parenchymal cells in the unique liver microenvironment play critical roles in promoting liver tolerogenicity. Of these, liver interstitial dendritic cells (DCs) are heterogeneous, innate immune cells that appear to play pivotal roles in the instigation, integration and regulation of inflammatory responses after liver transplantation. Interstitial liver DCs (recruited in situ or derived from circulating precursors) have been implicated in regulation of both ischemia/reperfusion injury (IRI) and anti-donor immunity. Thus, livers transplanted from mice constitutively lacking DCs into syngeneic, wild-type recipients, display increased tissue injury, indicating a protective role of liver-resident donor DCs against transplant IRI. Also, donor DC depletion before transplant prevents mouse spontaneous liver allograft tolerance across major histocompatibility complex (MHC) barriers. On the other hand, mouse liver graft-infiltrating host DCs that acquire donor MHC antigen via "cross-dressing", regulate anti-donor T cell reactivity in association with exhaustion of graft-infiltrating T cells and promote allograft tolerance. In an early phase clinical trial, infusion of donor-derived regulatory DCs (DCreg) before living donor liver transplantation can induce alterations in host T cell populations that may be conducive to attenuation of anti-donor immune reactivity. We discuss the role of DCs in regulation of warm and liver transplant IRI and the induction of liver allograft tolerance. We also address design of cell therapies using DCreg to reduce the immunosuppressive drug burden and promote clinical liver allograft tolerance.


Assuntos
Células Dendríticas/imunologia , Rejeição de Enxerto/imunologia , Transplante de Fígado , Fígado/imunologia , Traumatismo por Reperfusão/imunologia , Tolerância ao Transplante , Animais , Sobrevivência de Enxerto/imunologia , Humanos , Transplante Homólogo
8.
JCI Insight ; 6(12)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34032636

RESUMO

Alloimmune responses driven by donor-specific antibodies (DSAs) can lead to antibody-mediated rejection (ABMR) in organ transplantation. Yet, the cellular states underlying alloreactive B cell responses and the molecular components controlling them remain unclear. Using high-dimensional profiling of B cells in a cohort of 96 kidney transplant recipients, we identified expanded numbers of CD27+CD21- activated memory (AM) B cells that expressed the transcription factor T-bet in patients who developed DSAs and progressed to ABMR. Notably, AM cells were less frequent in DSA+ABMR- patients and at baseline levels in DSA- patients. RNA-Seq analysis of AM cells in patients undergoing ABMR revealed these cells to be poised for plasma cell differentiation and to express restricted IGHV sequences reflective of clonal expansion. In addition to T-bet, AM cells manifested elevated expression of interferon regulatory factor 4 and Blimp1, and upon coculture with autologous T follicular helper cells, differentiated into DSA-producing plasma cells in an IL-21-dependent manner. The frequency of AM cells was correlated with the timing and severity of ABMR manifestations. Importantly, T-bet+ AM cells were detected within kidney allografts along with their restricted IGHV sequences. This study delineates a pivotal role for AM cells in promoting humoral responses and ABMR in organ transplantation and highlights them as important therapeutic targets.


Assuntos
Linfócitos B , Rejeição de Enxerto/imunologia , Transplante de Rim/efeitos adversos , Ativação Linfocitária/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Humanos , Receptores de Complemento 3d , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral
9.
Transplantation ; 105(11): e168-e180, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33909968

RESUMO

Humoral allogeneic immunity driven by anti-HLA donor-specific antibodies and antibody-mediated rejection (AMR) significantly impede prolonged survival of organ allografts after transplantation. Although the importance of T follicular helper (TFH) cells in controlling antibody responses has been long established, their role in directing donor-specific antibody generation leading to AMR was only recently appreciated in the clinical setting of organ transplantation. In this review, we provide a comprehensive summary of the current knowledge on the biology of human TFH cells as well as their circulating counterparts and describe their pivotal role in driving humoral alloimmunity. In addition, we discuss the intrinsic effects of current induction therapies and maintenance immunosuppressive drugs as well as of biotherapies on TFH cells and provide future directions and novel opportunities of biotherapeutic targeting of TFH cells that have the potential of bringing the prophylactic and curative treatments of AMR toward personalized and precision medicine.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Transplante de Órgãos , Rejeição de Enxerto/prevenção & controle , Humanos , Imunidade Humoral , Transplante de Órgãos/efeitos adversos , Células T Auxiliares Foliculares , Linfócitos T Auxiliares-Indutores
10.
Am J Transplant ; 21(7): 2372-2386, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33171019

RESUMO

Regulatory dendritic cells (DCreg) promote transplant tolerance following their adoptive transfer in experimental animals. We investigated the feasibility, safety, fate, and impact on host T cells of donor monocyte-derived DCreg infused into prospective, living donor liver transplant patients, 7 days before transplantation. The DCreg expressed a tolerogenic gene transcriptional profile, high cell surface programed death ligand-1 (PD-L1):CD86 ratios, high IL-10/no IL-12 productivity and poor ability to stimulate allogeneic T cell proliferation. Target DCreg doses (range 2.5-10 × 106 cells/kg) were achieved in all but 1 of 15 recipients, with no infusion reactions. Following DCreg infusion, transiently elevated levels of donor HLA and immunoregulatory PD-L1, CD39, and CD73 were detected in circulating small extracellular vesicles. At the same time, flow and advanced image stream analysis revealed intact DCreg and "cross-dressing" of host DCs in blood and lymph nodes. PD-L1 co-localization with donor HLA was observed at higher levels than with recipient HLA. Between DCreg infusion and transplantation, T-bethi Eomeshi memory CD8+ T cells decreased, whereas regulatory (CD25hi CD127- Foxp3+ ): T-bethi Eomeshi CD8+ T cell ratios increased. Thus, donor-derived DCreg infusion may induce systemic changes in host antigen-presenting cells and T cells potentially conducive to modulated anti-donor immune reactivity at the time of transplant.


Assuntos
Transplante de Fígado , Animais , Bandagens , Linfócitos T CD8-Positivos , Células Dendríticas , Sobrevivência de Enxerto , Humanos , Doadores Vivos , Estudos Prospectivos , Subpopulações de Linfócitos T , Linfócitos T Reguladores
11.
J Am Soc Nephrol ; 31(10): 2457-2474, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32723838

RESUMO

BACKGROUND: Although antibody-mediated rejection (ABMR) has been long recognized as a leading cause of allograft failure after kidney transplantation, the cellular and molecular processes underlying the induction of deleterious donor-specific antibody (DSA) responses remain poorly understood. METHODS: Using high-dimensional flow cytometry, in vitro assays, and RNA sequencing, we concomitantly investigated the role of T follicular helper (TFH) cells and B cells during ABMR in 105 kidney transplant recipients. RESULTS: There were 54 patients without DSAs; of those with DSAs, ABMR emerged in 20 patients, but not in 31 patients. We identified proliferating populations of circulating TFH cells and activated B cells emerging in blood of patients undergoing ABMR. Although these circulating TFH cells comprised heterogeneous phenotypes, they were dominated by activated (ICOS+PD-1+) and early memory precursor (CCR7+CD127+) subsets, and were enriched for the transcription factors IRF4 and c-Maf. These circulating TFH cells produced large amounts of IL-21 upon stimulation with donor antigen and induced B cells to differentiate into antibody-secreting cells that produced DSAs. Combined analysis of the matched circulating TFH cell and activated B cell RNA-sequencing profiles identified highly coordinated transcriptional programs in circulating TFH cells and B cells among patients with ABMR, which markedly differed from those of patients who did not develop DSAs or ABMR. The timing of expansion of the distinctive circulating TFH cells and activated B cells paralleled emergence of DSAs in blood, and their magnitude was predictive of IgG3 DSA generation, more severe allograft injury, and higher rate of allograft loss. CONCLUSIONS: Patients undergoing ABMR may benefit from monitoring and therapeutic targeting of TFH cell-B cell interactions.


Assuntos
Formação de Anticorpos/fisiologia , Linfócitos B/fisiologia , Rejeição de Enxerto/sangue , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Células T Auxiliares Foliculares/fisiologia , Estudos de Casos e Controles , Citocinas/sangue , Feminino , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Isoanticorpos/sangue , Falência Renal Crônica/sangue , Falência Renal Crônica/imunologia , Masculino
12.
Kidney Int Rep ; 4(3): 455-469, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30899873

RESUMO

INTRODUCTION: The cellular events that contribute to generation of donor-specific anti-HLA antibodies (DSA) post-kidney transplantation (KTx) are not well understood. Characterization of such mechanisms could allow tailoring of immunosuppression to benefit sensitized patients. METHODS: We prospectively monitored circulating T follicular helper (cTFH) cells in KTx recipients who received T-cell depleting (thymoglobulin, n = 54) or T-cell nondepleting (basiliximab, n = 20) induction therapy from pre-KTx to 1 year post-KTx and assessed their phenotypic changes due to induction and DSA occurrence, in addition to healthy controls (n = 13), for a total of 307 blood samples. RESULTS: Before KTx, patients displayed comparable levels of resting, central memory cTFH cells with similar polarization to those of healthy controls. Unlike basiliximab induction, thymoglobulin induction significantly depleted cTFH cells, triggered lymphopenia-induced proliferation that skewed cTFH cells toward increased Th1 polarization, effector memory, and elevated programmed cell death protein 1 (PD-1)int/hi expression, resembling activated phenotypes. Regardless of induction, patients who developed DSA post-KTx, harbored pre-KTx donor-reactive memory interleukin (IL)-21+ cTFH cells and showed higher % cTFH and lower % of T regulatory (TREG) cells post-KTx resulting in elevated cTFH:TREG ratio at DSA occurrence. CONCLUSION: Induction therapy distinctly shapes cTFH cell phenotype post-KTx. Monitoring cTFH cells before and after KTx may help detect those patients prone to DSA generation post-KTx.

13.
Porto Alegre; s.n; 2019. 16 p.
Tese em Português | Coleciona SUS | ID: biblio-1023035

RESUMO

O presente texto/artigo é fruto do processo de formação e do trabalho de conclusão da Residência Multiprofissional em Saúde Mental e tem como temática de pesquisa os "ouvidores de vozes". O objetivo dessa problematização foi a de construir reflexões acerca da experiência de ouvir vozes a partir do entendimento de quem as ouve. Fundamentado nas obras de Romme, Escher e Backer, sendo referências internacionais no assunto, além de autores brasileiros como Muños, Kantorski, Barros e Sarpa Júnior. Esses autores compartilham da ideia de que a experiência de ouvir vozes não consiste necessariamente em um sintoma de doença, e que o fato de ouvir vozes não é o principal problema, mas na dificuldade de estabelecer algum tipo de relação ou convivência com elas. A pesquisa tem uma abordagem qualitativa e como procedimentos metodológicos operou-se com grupo focal a que consiste em uma técnica de coleta de dados que discute tópicos sugeridos pelo pesquisador, por meio das interações grupais, o qual foi realizado com usuários que já experienciaram ouvir vozes e que estão em tratamento em um Centro de Atenção Psicossocial II, do município de Porto Alegre. Os participantes do estudo entendem suas experiências de ouvir vozes de forma singular de acordo com suas culturas e crenças, mas todo o grupo percebe que há influência da forma como lidam com as vozes e suas relações sociais. Assim se aproxima o tema a uma perspectiva do Serviço Social a fim de contribuir com essas relações entre o social e o subjetivo. (AU)


Assuntos
Humanos , Masculino , Feminino , Serviço Social , Sistema Único de Saúde , Brasil , Saúde Mental , Saúde Pública , Relações Interpessoais
14.
Porto Alegre; s.n; 2019. 16 p. Obtenção do grau de Especialista em Saúde Mental Núcleo Serviço Social.
Tese em Português | LILACS | ID: biblio-1023039

RESUMO

O presente texto/artigo é fruto do processo de formação e do trabalho de conclusão da Residência Multiprofissional em Saúde Mental e tem como temática de pesquisa os "ouvidores de vozes". O objetivo dessa problematização foi a de construir reflexões acerca da experiência de ouvir vozes a partir do entendimento de quem as ouve. Fundamentado nas obras de Romme, Escher e Backer, sendo referências internacionais no assunto, além de autores brasileiros como Muños, Kantorski, Barros e Sarpa Júnior. Esses autores compartilham da ideia de que a experiência de ouvir vozes não consiste necessariamente em um sintoma de doença, e que o fato de ouvir vozes não é o principal problema, mas na dificuldade de estabelecer algum tipo de relação ou convivência com elas. A pesquisa tem uma abordagem qualitativa e como procedimentos metodológicos operou-se com grupo focal a que consiste em uma técnica de coleta de dados que discute tópicos sugeridos pelo pesquisador, por meio das interações grupais, o qual foi realizado com usuários que já experienciaram ouvir vozes e que estão em tratamento em um Centro de Atenção Psicossocial II, do município de Porto Alegre. Os participantes do estudo entendem suas experiências de ouvir vozes de forma singular de acordo com suas culturas e crenças, mas todo o grupo percebe que há influência da forma como lidam com as vozes e suas relações sociais. Assim se aproxima o tema a uma perspectiva do Serviço Social a fim de contribuir com essas relações entre o social e o subjetivo. (AU)


Assuntos
Humanos , Masculino , Feminino , Serviço Social , Sistema Único de Saúde , Brasil , Saúde Mental , Saúde Pública , Relações Interpessoais
15.
Transplantation ; 102(5): e195-e204, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29266033

RESUMO

BACKGROUND: We investigated in vitro whether HLA highly sensitized patients with end-stage renal disease will be disadvantaged immunologically after a genetically engineered pig kidney transplant. METHODS: Blood was drawn from patients with a calculated panel-reactive antibody (cPRA) 99% to 100% (Gp1, n = 10) or cPRA 0% (Gp2, n = 12), and from healthy volunteers (Gp3, n = 10). Serum IgM and IgG binding was measured (i) to galactose-α1-3 galactose and N-glycolylneuraminic acid glycans by enzyme-linked immunosorbent assay, and (ii) to pig red blood cell, pig aortic endothelial cells, and pig peripheral blood mononuclear cell from α1,3-galactosyltransferase gene-knockout (GTKO)/CD46 and GTKO/CD46/cytidine monophosphate-N-acetylneuraminic acid hydroxylase-knockout (CMAHKO) pigs by flow cytometry. (iii) T-cell and B-cell phenotypes were determined by flow cytometry, and (iv) proliferation of T-cell and B-cell carboxyfluorescein diacetate succinimidyl ester-mixed lymphocyte reaction. RESULTS: (i) By enzyme-linked immunosorbent assay, there was no difference in IgM or IgG binding to galactose-α1-3 galactose or N-glycolylneuraminic acid between Gps1 and 2, but binding was significantly reduced in both groups compared to Gp3. (ii) IgM and IgG binding in Gps1 and 2 was also significantly lower to GTKO/CD46 pig cells than in healthy controls, but there were no differences between the 3 groups in binding to GTKO/CD46/CMAHKO cells. (iii and iv) Gp1 patients had more memory T cells than Gp2, but there was no difference in T or B cell proliferation when stimulated by any pig cells. The proliferative responses in all 3 groups were weakest when stimulated by GTKO/CD46/CMAHKO pig peripheral blood mononuclear cell. CONCLUSIONS: (i) End-stage renal disease was associated with low antipig antibody levels. (ii) Xenoreactivity decreased with increased genetic engineering of pig cells. (iii) High cPRA status had no significant effect on antibody binding or T-cell and B-cell response.


Assuntos
Galactosiltransferases/genética , Antígenos HLA/imunologia , Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Proteína Cofatora de Membrana/genética , Oxigenases de Função Mista/genética , Animais , Animais Geneticamente Modificados , Linfócitos B/imunologia , Estudos de Casos e Controles , Células Cultivadas , Galactosiltransferases/deficiência , Galactosiltransferases/imunologia , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Antígenos HLA/sangue , Xenoenxertos , Humanos , Memória Imunológica , Isoanticorpos/sangue , Isoanticorpos/imunologia , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/imunologia , Transplante de Rim/efeitos adversos , Ativação Linfocitária , Proteína Cofatora de Membrana/deficiência , Proteína Cofatora de Membrana/imunologia , Oxigenases de Função Mista/deficiência , Oxigenases de Função Mista/imunologia , Sus scrofa , Linfócitos T/imunologia
16.
Cell Immunol ; 323: 9-18, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29217299

RESUMO

Human regulatory dendritic cells (DCreg) were generated from CD14 immunobead-purified or elutriated monocytes in the presence of vitamin D3 and IL-10. They exhibited similar, low levels of costimulatory CD80 and CD86, but comparatively high levels of co-inhibitory programed death ligand-1 (PD-L1) and IL-10 production compared to control immature DC (iDC). Following Toll-like receptor 4 ligation, unlike control iDC, DCreg resisted phenotypic and functional maturation and further upregulated PD-L1:CD86 expression. Whereas LPS-stimulated control iDC (mature DC; matDC) secreted pro-inflammatory tumor necrosis factor but no IL-10, the converse was observed for LPS-stimulated DCreg. DCreg weakly stimulated naïve and memory allogeneic CD4+ and CD8+ T cell proliferation and IFNγ, IL-17A and perforin/granzyme B production in MLR. Their stimulatory function was enhanced however, by blocking PD-1 ligation. High-throughput T cell receptor (TCR) sequencing revealed that, among circulating T cell subsets, memory CD8+ T cells contained the most alloreactive TCR clonotypes and that, while matDC expanded these alloreactive memory CD8 TCR clonotypes, DCreg induced more attenuated responses. These findings demonstrate the feasibility of generating highly-purified GMP-grade DCreg for systemic infusion, their influence on the alloreactive T cell response, and a key mechanistic role of the PD1 pathway.


Assuntos
Antígeno B7-2/imunologia , Antígeno B7-H1/imunologia , Células Dendríticas/imunologia , Diferenciação Celular/imunologia , Células Dendríticas/citologia , Humanos , Interleucina-10/imunologia , Ativação Linfocitária , Monócitos/imunologia , Transplante de Órgãos/métodos , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Imunologia de Transplantes
17.
Front Med (Lausanne) ; 4: 185, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29164120

RESUMO

Despite potent immunosuppression, clinical and biopsy confirmed acute renal allograft rejection (AR) still occurs in 10-15% of recipients, ~30% of patients demonstrate subclinical rejection on biopsy, and ~50% of them can show molecular inflammation, all which increase the risk of chronic dysfunction and worsened allograft outcomes. Mitochondria represent intracellular endogenous triggers of inflammation, which can regulate immune cell differentiation, and expansion and cause antigen-independent graft injury, potentially enhancing the development of acute rejection. In the present study, we investigated the role of mitochondrial DNA encoded gene expression in biopsy matched peripheral blood (PB) samples from kidney transplant recipients. Quantitative PCR was performed in 155 PB samples from 115 unique pediatric (<21 years) and adult (>21 years) renal allograft recipients at the point of AR (n = 61) and absence of rejection (n = 94) for the expression of 11 mitochondrial DNA encoded genes. We observed increased expression of all genes in adult recipients compared to pediatric recipients; separate analyses in both cohorts demonstrated increased expression during rejection, which also differentiated borderline rejection and showed an increasing pattern in serially collected samples (0-3 months prior to and post rejection). Our results provide new insights on the role of mitochondria during rejection and potentially indicate mitochondria as targets for novel immunosuppression.

18.
Transplantation ; 101(11): 2731-2738, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28594751

RESUMO

BACKGROUND: The human regulatory macrophage (Mreg) has emerged as a promising cell type for use as a cell-based adjunct immunosuppressive therapy in solid organ transplant recipients. In this brief report, dehydrogenase/reductase 9 (DHRS9) is identified as a robust marker of human Mregs. METHODS: The cognate antigen of a mouse monoclonal antibody raised against human Mregs was identified as DHRS9 by immunoprecipitation and MALDI-MS sequencing. Expression of DHRS9 within a panel of monocyte-derived macrophages was investigated by quantitative PCR, immunoblotting and flow cytometry. RESULTS: DHRS9 expression discriminated human Mregs from a panel of in vitro derived macrophages in other polarisation states. Likewise, DHRS9 expression distinguished Mregs from a variety of human monocyte-derived tolerogenic antigen-presenting cells in current development as cell-based immunotherapies, including Tol-DC, Rapa-DC, DC-10, and PGE2-induced myeloid-derived suppressor cells. A subpopulation of DHRS9-expressing human splenic macrophages was identified by immunohistochemistry. Expression of DHRS9 was acquired gradually during in vitro development of human Mregs from CD14 monocytes and was further enhanced by IFN-γ treatment on day 6 of culture. Stimulating Mregs with 100 ng/mL lipopolysaccharide for 24 hours did not extinguish DHRS9 expression. Dhrs9 was not an informative marker of mouse Mregs. CONCLUSION: DHRS9 is a specific and stable marker of human Mregs.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Ativação de Macrófagos , Macrófagos/enzimologia , 3-Hidroxiesteroide Desidrogenases/genética , Animais , Biomarcadores/metabolismo , Células Cultivadas , Regulação Enzimológica da Expressão Gênica , Humanos , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Especificidade da Espécie , Fatores de Tempo
19.
PLoS One ; 12(4): e0176460, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28445506

RESUMO

Human monocytes have been grouped into classical (CD14++CD16-), non-classical (CD14dimCD16++), and intermediate (CD14++CD16+) subsets. Documentation of normal function and variation in this complement of subtypes, particularly their differentiation potential to dendritic cells (DC) or macrophages, remains incomplete. We therefore phenotyped monocytes from peripheral blood of healthy subjects and performed functional studies on high-speed sorted subsets. Subset frequencies were found to be tightly controlled over time and across individuals. Subsets were distinct in their secretion of TNFα, IL-6, and IL-1ß in response to TLR agonists, with classical monocytes being the most producers and non-classical monocytes the least. Monocytes, particularly those of the non-classical subtype, secreted interferon-α (IFN-α) in response to intracellular TLR3 stimulation. After incubation with IL-4 and GM-CSF, classical monocytes acquired monocyte-derived DC (mo-DC) markers and morphology and stimulated allogeneic T cell proliferation in MLR; intermediate and non-classical monocytes did not. After incubation with IL-3 and Flt3 ligand, no subset differentiated to plasmacytoid DC. After incubation with GM-CSF (M1 induction) or macrophage colony-stimulating factor (M-CSF) (M2 induction), all subsets acquired macrophage morphology, secreted macrophage-associated cytokines, and displayed enhanced phagocytosis. From these studies we conclude that classical monocytes are the principal source of mo-DCs, but all subsets can differentiate to macrophages. We also found that monocytes, in particular the non-classical subset, represent an alternate source of type I IFN secretion in response to virus-associated TLR agonists.


Assuntos
Diferenciação Celular , Monócitos/citologia , Monócitos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Imunofenotipagem , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Microscopia de Fluorescência , Fagocitose/efeitos dos fármacos , Fenótipo , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
Rev. enferm. UFPE on line ; 10(5): 4271-4278, maio 2016. tab, graf
Artigo em Inglês, Português | BDENF - Enfermagem | ID: biblio-1031693

RESUMO

Objetivo: coletar dados e informações para subsidiar o dimensionamento da equipe de enfermagem na unidade de clínica médica do Hospital Universitário de Brasília. Método: estudo descritivo-aplicado, de abordagem quantitativa. A análise dos dados foi realizada a partir da estatística pela soma dos escores após a classificação dos pacientes por necessidade de cuidado, multiplicadas as horas necessárias para cada paciente nas 24 horas e calculada a quantidade de pessoal. Resultados: maior prevalência de pacientes de cuidados mínimos, quantidade de pessoal média calculada igual a 60, sendo 20 enfermeiros e 40 técnicos. Conclusão: a aplicação de estudo sobre dimensionamento de pessoal de enfermagem auxilia a tomada de decisões quanto à necessidade e alocação de recursos humanos.(AU)


Objective: to collect data and information to subsidize the nursing staff dimensioning in the medical clinic unit of the University Hospital of Brasília. Method: this is a descriptive study with a quantitative approach. The analysis of the data was performed from the statistics by the sum of the scores after the classification of the patients by need of care, multiplied the necessary hours for each patient in the 24 hours and calculated the amount of personnel. Results: there is a higher prevalence of patients with minimal care, average number of staff calculated was 60, 20 nurses and 40 nursing technicians. Conclusion: the application of a study on nursing personnel dimensioning helps to make decisions regarding the need and allocation of human resources.(AU)


Objetivo: recoger los datos e informaciones para subsidiar el dimensionamiento del equipo de enfermería en la unidad de clínica médica del Hospital Universitario de Brasília. Método: estudio descriptivo-aplicado, de enfoque cuantitativo. El análisis de los datos fue realizada a partir de la estadística por la soma de los puntos después de la clasificación de los pacientes por necesidad de cuidado, multiplicado por las horas necesarias para cada paciente en las 24 horas y calculado la cantidad de personal. Resultados: mayor prevalencia de pacientes de cuidados mínimos, cantidad de personal média calculada igual a 60, siendo 20 enfermeros y 40 técnicos. Conclusión: la aplicación de estudio sobre dimensionamiento de personal de enfermería auxilia a la tomada de decisiones para la necesidad y alocación de recursos humanos.(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Cuidados de Enfermagem , Equipe de Enfermagem , Hospitais Universitários , Pesquisa em Administração de Enfermagem , Recursos Humanos de Enfermagem Hospitalar , Epidemiologia Descritiva , Processo de Enfermagem
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