RESUMO
Jak inhibitors are increasingly used in dermatology. Despite broad inhibitory effects on cytokine signaling cascades, they only modestly increase the risk for infectious diseases. To address the molecular mechanisms underlying this unexpected clinical observation, we investigated how tofacintib (tofa), a first-in-class Jak inhibitor, regulates host defense responses in toll-like receptor 4-activated human macrophages. Specifically, we asked whether tofa inhibits anti-inflammatory IL-10 signaling, thereby counteracting the downregulation of inflammatory, host-protective pathways. We found that tofa blocked macrophage responses to IL-10 at the level of signal transducer and activator of transcription 3 phosphorylation. Furthermore, toll-like receptor 4-induced, autocrine/paracrine IL-10/IL-10R activation promoted the expression of hepcidin, the master regulator of iron metabolism, resulting in intracellular iron sequestration. In contrast, autocrine/paracrine IL-10/IL-10R activation repressed the expression of cathelicidin antimicrobial peptide as well as antigen-presenting molecules, thus together, inducing a pathogen-favoring environment. Although tofa further repressed cathelicidin, it prevented the induction of intracellular HAMP and restored the expression of antigen-presentation molecules in toll-like receptor 4-activated macrophages. Our study supports the concept that induction of IL-10/IL-10R signaling drives a complex immune evasion strategy of intracellular microbes. Moreover, we conclude that tofa has diverging effects on macrophage host response pathways, and we identify the toll-like receptor 4-IL-10-signal transducer and activator of transcription 3-HAMP axis as a potential therapeutic target to counteract immune evasion.
Assuntos
Inibidores de Janus Quinases , Receptor 4 Toll-Like , Humanos , Interleucina-10/metabolismo , Ferro/metabolismo , Inibidores de Janus Quinases/farmacologia , Macrófagos/metabolismo , Piperidinas , Pirimidinas , Fator de Transcrição STAT3/metabolismo , Receptor 4 Toll-Like/metabolismoAssuntos
Suscetibilidade a Doenças/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Mastócitos/imunologia , Animais , Modelos Animais de Doenças , Humanos , Leishmaniose Cutânea/parasitologia , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Infiltração de Neutrófilos , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Células Th17/microbiologiaAssuntos
Células de Langerhans/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Linfócitos T Reguladores/imunologia , Animais , Antígenos de Superfície/metabolismo , Modelos Animais de Doenças , Humanos , Células de Langerhans/metabolismo , Lectinas Tipo C/metabolismo , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Contagem de Linfócitos , Lectinas de Ligação a Manose/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Pele/citologia , Pele/imunologia , Pele/parasitologia , Pele/patologia , Organismos Livres de Patógenos EspecíficosRESUMO
Humanized mice represent a suitable preclinical test system for example therapeutic interventions in various disease settings, including infections. Here, we intended to establish such system for cutaneous leishmaniasis by infecting T, B and NK cell-deficient mice adoptively transferred with human peripheral blood mononuclear cells (PBMC). L major infection led to the establishment of parasite lesions harbouring viable parasites and human T cells, but parasite elimination was not seen due to a species-specific activity of T cell-derived human IFNγ. In addition, up to 50% of infected mice succumbed to severe graft-versus-host disease. In summary, even though long-term disease outcome assessments are impossible, this model of humanized mice can be used for studying lesion development and generation of oligoclonal anti-parasite human T cell responses in vivo.
Assuntos
Transferência Adotiva , Leishmaniose Cutânea/terapia , Leucócitos Mononucleares/transplante , Subpopulações de Linfócitos T/transplante , Transferência Adotiva/efeitos adversos , Animais , Progressão da Doença , Doença Enxerto-Hospedeiro/etiologia , Xenoenxertos , Humanos , Interferon gama/farmacologia , Leishmaniose Cutânea/parasitologia , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Camundongos , Modelos Animais , Especificidade da Espécie , Subpopulações de Linfócitos T/imunologiaRESUMO
Proinflammatory IL-17 plays an important role in various diseases and defence against extracellular microorganisms. Healing of leishmaniasis is promoted by Th1/Tc1 cells, whereas Th2/Treg are associated with worsened disease outcome. In addition, high expression of IL-17A in Leishmania-susceptible BALB/c and artificial overexpression of IL-17A in T cells in resistant C57BL/6 mice worsened disease outcome. Since C57BL/6 mice lacking only IL-17A exhibited no phenotype, and IL-17A and IL-17F share similar receptors, but differentially regulate chemokine secretion, we studied mice lacking both IL-17A and IL-17F (IL-17A/F-/- ) in infections with Leishmania major. Interestingly, lesion volumes and parasite burdens were comparable to controls, IL-17A/F-/- mice developed a Th1/Tc1 phenotype, and exhibited normal lesion resolution. Thus, in C57BL/6 mice, secretion of IL-17A and IL-17F does not influence disease progression. It appears that-depending on the genetic background-cytokines of the IL-17 family might be responsible for disease progression primarily in susceptible mice.
Assuntos
Interleucina-17/imunologia , Leishmaniose/imunologia , Células Th1/parasitologia , Células Th2/parasitologia , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/parasitologia , Cruzamentos Genéticos , Citocinas/metabolismo , Progressão da Doença , Feminino , Linfócitos Intraepiteliais/citologia , Linfócitos Intraepiteliais/parasitologia , Leishmania/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fenótipo , Células Th1/citologia , Células Th2/citologiaRESUMO
Healing of leishmaniasis-a parasitic skin disease-is associated with high levels of secreted interferon (IFN)γ and IL-12 in resistant C57BL/6 mice and humans. Susceptible BALB/c mice predominantly react with a Th17/Th2/Treg-related immune response and finally succumb to infection. Previously, we showed that BALB/c IL-17A-/- mice are protected against Leishmania (L.) major infections, indicating that IL-17A-predominantly produced by Th17 cells-plays an important role for disease outcome. We now investigated DC-derived cytokines and finally identified IL-23p19 as key cytokine responsible for induction of Leishmania-specific Th17 cells that play an important role for progressive disease in susceptible BALB/c mice.
Assuntos
Subunidade p19 da Interleucina-23/genética , Leishmaniose Cutânea/imunologia , Células Th17/citologia , Animais , Citocinas/metabolismo , Células Dendríticas/metabolismo , Progressão da Doença , Interferon gama/metabolismo , Leishmania major , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Células Th17/imunologiaAssuntos
Interações Hospedeiro-Parasita/imunologia , Células de Langerhans/metabolismo , Leishmaniose Cutânea/imunologia , Linfócitos T Reguladores/imunologia , Tretinoína/metabolismo , Animais , Comunicação Celular/imunologia , Modelos Animais de Doenças , Humanos , Células de Langerhans/imunologia , Leishmania major/imunologia , Leishmania major/patogenicidade , Leishmaniose Cutânea/parasitologia , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Knockout , Receptores CCR7/genética , Receptores CCR7/imunologia , Pele/citologia , Pele/imunologia , Tretinoína/imunologiaRESUMO
Gender-associated differences in the outcome of infections are well known. Apart from behavior-released differences in their incidence, immunological factors also contribute to disease outcome. The underlying mechanisms are often unknown. Here, we show that in murine experimental leishmaniasis, female mice develop larger skin lesions that harbor significantly more parasites, exhibit increased parasite dissemination to visceral organs associated with a shift towards T helper (Th) 2 immunity with increased levels of IL-4. Antigen presenting cells (APC) responsible for T cell priming, such as macrophages or dendritic cells, were not involved in the process. Additionally, in adoptive transfer experiments, we show that differences in the lymphoid lineage are also not critical for mediating these gender-dependent effects. In summary, neither myeloid nor lymphoid cells contribute to disease outcome against this important human pathogen, but stromal cells influenced by e.g. hormonal effects in addition to other parts of the immune system might play a role.
Assuntos
Hormônios/metabolismo , Leishmaniose Cutânea/imunologia , Sexo , Células Estromais/imunologia , Células Th2/imunologia , Animais , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Suscetibilidade a Doenças , Feminino , Humanos , Interleucina-4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/imunologia , Células Mieloides/parasitologia , Células Estromais/parasitologia , Equilíbrio Th1-Th2 , Células Th2/parasitologiaAssuntos
Interleucina-17/imunologia , Subunidade p19 da Interleucina-23/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Células Th17/imunologia , Animais , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Interleucina-17/genética , Subunidade p19 da Interleucina-23/genética , Leishmaniose Cutânea/genética , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NeutrófilosAssuntos
Células Dendríticas/imunologia , Memória Imunológica/imunologia , Interleucina-10/metabolismo , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Animais , Modelos Animais de Doenças , Interleucina-10/imunologia , Leishmania major/patogenicidade , Leishmaniose Cutânea/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Transdução de Sinais/imunologiaRESUMO
T cells can be found in skin under steady-state conditions as well as in inflammatory processes. T cells in skin play an important role in immune homeostasis as well as control of infectious, inflammatory diseases or tumors. In addition, several important and frequent skin diseases such as psoriasis, atopic dermatitis, autoimmune disease, and contact allergy are initiated by T cells. In skin diseases, the majority of antigen-specific T cells can be found in the tissue, not the peripheral blood. Here, we present a protocol suitable for isolation of skin-resident (inflammatory) T cells that can be used for an in-depth characterization of their frequency, function, and role for the respective inflammatory condition.
Assuntos
Pele/citologia , Pele/imunologia , Linfócitos T/citologia , Animais , Separação Celular/métodos , Dermatite/imunologia , Dermatite/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T/patologiaRESUMO
Leishmaniasis is a parasitic infection affecting â¼12 million people worldwide, mostly in developing countries. Treatment options are limited and no effective vaccines exist to date. Natural Killer T (NKT) cells are a conserved innate-like lymphocyte population with immunomodulating effects in various settings. A number of reports state a role of NKT cells in different models of Leishmania infection. Here, we investigated the effect of NKT cells in a physiologically relevant, intradermal low dose infection model. After inoculation of 103 infectious-stage L. major, comparable numbers of skin-immigrating NKT cells in both susceptible BALB/c mice and resistant C57BL/6 mice were noted. Compared to their wild type counterparts, NKT cell-deficient mice on a C57BL/6 background were better able to contain infection with L. major and showed decreased IL-4 production in cytokine analysis performed 5 and 8 weeks after infection. Low doses of the NKT cell stimulating αGalCer analog PBS57 applied at the time of infection led to disease exacerbation in C57BL/6 wild-type, but not NKT-deficient mice. The effect was dependent both on the timing and amount of PBS57 administered. The effect of NKT cell stimulation by PBS57 proved to be IL-4 dependent, as it was neutralized in IL-4-deficient C57BL/6 or anti-IL-4 antibody-treated wild-type mice. In contrast to C57BL/6 mice, administration of PBS57 in susceptible BALB/c mice resulted in an improved course of disease. Our results reveal a strain- and cytokine-dependent regulatory role of NKT cells in the development of immunity to low dose L. major infections. These effects, probably masked in previous studies using higher parasite inocula, should be considered in future therapy and immunization approaches.