RESUMO
BACKGROUND: Allergic contact dermatitis (CD) is a chronic inflammatory skin disease caused by type 1 biased adaptive immunity for which there is an unmet need for antigen (Ag)-specific immunotherapies. Exposure to skin sensitizers stimulates secretion of the proinflammatory neuropeptides substance P and hemokinin 1, which signal via the neurokinin-1 receptor (NK1R) to promote the innate and adaptive immune responses of CD. Accordingly, mice lacking the NK1R develop impaired CD. Nonetheless, the role and therapeutic opportunities of targeting the NK1R in CD remain to be elucidated. OBJECTIVE: We sought to develop an Ag-specific immunosuppressive approach to treat CD by skin codelivery of hapten and NK1R antagonists integrated in dissolvable microneedle arrays (MNA). METHODS: In vivo mouse models of contact hypersensitivity and ex vivo models of human skin were used to delineate the effects and mechanisms of NK1R signaling and the immunosuppressive effects of the contact sensitizer NK1R antagonist MNA in CD. RESULTS: We demonstrated in mice that CD requires NK1R signaling by substance P and hemokinin 1. Specific deletion of the NK1R in keratinocytes and dendritic cells, but not in mast cells, prevented CD. Skin codelivery of hapten or Ag MNA inhibited neuropeptide-mediated skin inflammation in mouse and human skin, promoted deletion of Ag-specific effector T cells, and increased regulatory T cells, which prevented CD onset and relapses locally and systemically in an Ag-specific manner. CONCLUSIONS: Immunoregulation by engineering localized skin neuroimmune networks can be used to treat cutaneous diseases that like CD are caused by type 1 immunity.
Assuntos
Dermatite Alérgica de Contato , Antagonistas dos Receptores de Neurocinina-1 , Animais , Dermatite Alérgica de Contato/tratamento farmacológico , Haptenos , Camundongos , Antagonistas dos Receptores de Neurocinina-1/farmacologia , Receptores da Neurocinina-1 , Substância PRESUMO
There is increasing evidence of the relevant connection and regulation between the gut and skin immune axis. In fact, oral administration of lipoteichoic acid (LTA) from Lactobacillus rhamnosus GG (LGG) prevents the development of UV-induced skin tumors in chronically exposed mice. Here we aim to evaluate whether this LTA is able to revert UV-induced immunosuppression as a mechanism involved in its anti-tumor effect and whether it has an immunotherapeutic effect against cutaneous squamous cell carcinoma. Using a mouse model of contact hypersensitivity, we demonstrate that LTA overcomes UV-induced skin immunosuppression. This effect was in part achieved by modulating the phenotype of lymph node resident dendritic cells (DC) and the homing of skin migratory DC. Importantly, oral LTA reduced significantly the growth of established skin tumors once UV radiation was discontinued, demonstrating that it has a therapeutic, besides the already demonstrated preventive antitumor effect. The data presented here strongly indicates that oral administration of LTA represents a promising immunotherapeutic approach for different conditions in which the skin immune system is compromised.
Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Lacticaseibacillus rhamnosus/química , Lipopolissacarídeos/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Ácidos Teicoicos/farmacologia , Raios Ultravioleta/efeitos adversos , Administração Oral , Animais , Antineoplásicos/isolamento & purificação , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Movimento Celular/efeitos da radiação , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/patologia , Células Dendríticas/efeitos da radiação , Dermatite de Contato/genética , Dermatite de Contato/imunologia , Dermatite de Contato/patologia , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/patologia , Trato Gastrointestinal/efeitos da radiação , Lipopolissacarídeos/isolamento & purificação , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Linfonodos/patologia , Linfonodos/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Pele/efeitos da radiação , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Ácidos Teicoicos/isolamento & purificaçãoRESUMO
The role and regulators of extracellular vesicle (EV) secretion in hepatic ischemia/reperfusion (IR) injury have not been defined. Rab27a is a guanosine triphosphatase known to control EV release. Interferon regulatory factor 1 (IRF-1) is a transcription factor that plays an important role in liver IR and regulates certain guanosine triphosphatases. However, the relationships among IRF-1, Rab27a, and EV secretion are largely unknown. Here, we show induction of IRF-1 and Rab27a both in vitro in hypoxic hepatocytes and in vivo in warm IR and orthotopic liver transplantation livers. Interferon γ stimulation, IRF-1 transduction, or IR promoted Rab27a expression and EV secretion. Meanwhile, silencing of IRF-1 decreased Rab27a expression and EV secretion. Rab27a silencing decreased EV secretion and liver IR injury. Ten putative IRF-1 binding motifs in the 1,692-bp Rab27a promoter region were identified. Chromatin immunoprecipitation and electrophoretic mobility shift assay verified five functional IRF-1 binding motifs, which were confirmed by a Rab27a promoter luciferase assay. IR-induced EVs contained higher oxidized phospholipids (OxPL). OxPLs on the EV surface activated neutrophils through the toll-like receptor 4 pathway. OxPL-neutralizing E06 antibody blocked the effect of EVs and decreased liver IR injury. CONCLUSION: These findings provide a novel mechanism by which IRF-1 regulates Rab27a transcription and EV secretion, leading to OxPL activation of neutrophils and subsequent hepatic IR injury. (Hepatology 2018;67:1056-1070).
Assuntos
Vesículas Extracelulares/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Fígado/patologia , Traumatismo por Reperfusão/metabolismo , Proteínas rab27 de Ligação ao GTP/metabolismo , Animais , Técnicas de Cultura de Células , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Transplante de Fígado , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
Although a key role of cross-dressing has been established in immunity to viral infection and more recently in the instigation of transplant rejection, its role in tolerance is unclear. We investigated the role of intragraft dendritic cells (DCs) and cross-dressing in mouse major histocompatibility complex (MHC)-mismatched liver transplant tolerance that occurs without therapeutic immunosuppression. Although donor interstitial DCs diminished rapidly after transplantation, they were replaced in the liver by host DCs that peaked on postoperative day (POD) 7 and persisted indefinitely. Approximately 60% of these recipient DCs displayed donor MHC class I, indicating cross-dressing. By contrast, only a very minor fraction (0%-2%) of cross-dressed DCs (CD-DCs) was evident in the spleen. CD-DCs sorted from liver grafts expressed much higher levels of T cell inhibitory programed death ligand 1 (PD-L1) and high levels of interleukin-10 compared with non-CD-DCs (nCD-DCs) isolated from the graft. Concomitantly, high incidences of programed death protein 1 (PD-1)hi T cell immunoglobulin and mucin domain containing 3 (TIM-3)+ exhausted graft-infiltrating CD8+ T cells were observed. Unlike nCD-DCs, the CD-DCs failed to stimulate proliferation of allogeneic T cells but markedly suppressed antidonor host T cell proliferation. CD-DCs were much less evident in allografts from DNAX-activating protein of 12 kDa (DAP12)-/- donors that were rejected acutely. CONCLUSION: These findings suggest that graft-infiltrating PD-L1hi CD-DCs may play a key role in the regulation of alloimmunity and in the induction of liver transplant tolerance. (Hepatology 2018;67:1499-1515).
Assuntos
Células Dendríticas/imunologia , Sobrevivência de Enxerto/imunologia , Fígado/imunologia , Tolerância ao Transplante/imunologia , Animais , Citometria de Fluxo , Microscopia Intravital , Transplante de Fígado/efeitos adversos , Complexo Principal de Histocompatibilidade/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante HomólogoRESUMO
BACKGROUND: Memory T cells (Tmem), particularly those resistant to costimulation blockade (CB), are a major barrier to transplant tolerance. The transcription factor Eomesodermin (Eomes) is critical for Tmem development and maintenance, but its expression by alloactivated T cells has not been examined in nonhuman primates. METHODS: We evaluated Eomes and coinhibitory cytotoxic T lymphocyte antigen-4 (CTLA4) expression by alloactivated rhesus monkey T cells in the presence of CTLA4 immunoglobulin, both in vitro and in renal allograft recipients treated with CTLA4Ig, with or without regulatory dendritic cell (DCreg) infusion. RESULTS: In normal monkeys, CD8+ T cells expressed significantly more Eomes than CD4+ T cells. By contrast, CD8+ T cells displayed minimal CTLA4. Among T cell subsets, central Tmem (Tcm) expressed the highest levels of Eomes. Notably, Eomes(lo)CTLA4(hi) cells displayed higher levels of CD25 and Foxp3 than Eomes(hi)CTLA4(lo) CD8+ T cells. After allostimulation, distinct proliferating Eomes(lo)CTLA4(hi) and Eomes(hi)CTLA4(lo) CD8+ T cell populations were identified, with a high proportion of Tcm being Eomes(lo)CTLA4(hi). CB with CTLA4Ig during allostimulation of CD8+ T cells reduced CTLA4 but not Eomes expression, significantly reducing Eomes(lo)CTLA4(hi) cells. After transplantation with CB and rapamycin, donor-reactive Eomes(lo)CTLA4(hi) CD8+ T cells were reduced. However, in monkeys also given DCreg, absolute numbers of these cells were elevated significantly. CONCLUSIONS: Low Eomes and high CTLA4 expression by donor-reactive CD8+ Tmem is associated with prolonged renal allograft survival induced by DCreg infusion in CTLA4Ig-treated monkeys. Prolonged allograft survival associated with DCreg infusion may be related to maintenance of donor-reactive Eomes(lo)CTLA4(hi) Tcm.
Assuntos
Abatacepte/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Antígeno CTLA-4/metabolismo , Células Dendríticas/transplante , Sobrevivência de Enxerto/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Rim , Ativação Linfocitária/efeitos dos fármacos , Proteínas com Domínio T/metabolismo , Aloenxertos , Animais , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Antígeno CTLA-4/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Imunofenotipagem , Transplante de Rim/efeitos adversos , Macaca mulatta , Masculino , Fenótipo , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Sirolimo/farmacologia , Proteínas com Domínio T/imunologia , Fatores de TempoRESUMO
BACKGROUND: Efficient development of atopic diseases requires interactions between allergen and adjuvant to initiate and amplify the underlying inflammatory responses. Substance P (SP) and hemokinin-1 (HK-1) are neuropeptides that signal through the neurokinin-1 receptor (NK1R) to promote inflammation. Mast cells initiate the symptoms and tissue effects of atopic disorders, secreting TNF and IL-6 after FcεRI cross-linking by antigen-IgE complexes (FcεRI-activated mast cells [FcεRI-MCs]). Additionally, MCs express the NK1R, suggesting an adjuvant role for NK1R agonists in FcεRI-MC-mediated pathologies; however, in-depth research addressing this relevant aspect of MC biology is lacking. OBJECTIVE: We sought to investigate the effect of NK1R signaling and the individual roles of SP and HK-1 as potential adjuvants for FcεRI-MC-mediated allergic disorders. METHODS: Bone marrow-derived mast cells (BMMCs) from C57BL/6 wild-type (WT) or NK1R(-/-) mice were used to investigate the effects of NK1R signaling on FcεRI-MCs. BMMCs generated from Tac1(-/-) mice or after culture with Tac4 small interfering RNA were used to address the adjuvancy of SP and HK-1. WT, NK1R(-/-), and c-Kit(W-sh/W-sh) mice reconstituted with WT or NK1R(-/-) BMMCs were used to evaluate NK1R signaling on FcεRI-MC-mediated passive local and systemic anaphylaxis and on airway inflammation. RESULTS: FcεRI-activated MCs upregulated NK1R and HK-1 transcripts and protein synthesis, without modifying SP expression. In a positive signaling loop HK-1 promoted TNF and IL-6 secretion by MC degranulation and protein synthesis, the latter through the phosphoinositide 3-kinase/Akt/nuclear factor κB pathways. In vivo NK1R signaling was necessary for the development of passive local and systemic anaphylaxis and airway inflammation. CONCLUSIONS: FcεRI stimulation of MCs promotes autocrine secretion of HK-1, which signals through NK1R to provide adjuvancy for efficient development of FcεRI-MC-mediated disorders.
Assuntos
Comunicação Autócrina , Imunoglobulina E/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Mastócitos/imunologia , Mastócitos/metabolismo , Taquicininas/metabolismo , Anafilaxia/imunologia , Anafilaxia/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Interleucina-6/biossíntese , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Knockout , Receptores de IgE/metabolismo , Receptores da Neurocinina-1/metabolismo , Transdução de Sinais , Fatores de Necrose Tumoral/biossínteseRESUMO
Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease that destroys the insulin-secreting beta-cells of the pancreas. It is now possible to predict those candidates that will progress to T1D before the full onset of the disease. Prevention of uncontrollable autoimmunity against beta-cells in therapies for T1D is mandatory to preserve the beta-cell mass. Therefore, immunomodulatory strategies directed to inhibiting the activity of self-reactive T cell clones as well as induction of regulatory T cells would be beneficial for prevention of T1D or recurrence of beta-cell autoimmunity against islet cell allografts.