RESUMEN
Modified nanoparticles (NPs) can interact with the immune system by causing its activation to fight tumors or for vaccination. During this activation, dendritic cells (DCs) are effective in generating robust immune response. However, the effect of nanomaterials on dendritic cell (DC) maturation, and the associated adjuvant effect, should be assessed as a novel biocompatibility criteria for biomaterials since immune consequences may constitute potential complications in nanomedicine. Among emerging biomaterials, poly(lactic-co-glycolic acid) NPs (PLGA NPs) are widely explored for various applications in which the degree of desired adjuvant effect may vary. As contradictory results are reported regarding their effects on DCs, we aimed at clarifying this point with particular emphasis on the relative impact of particle surface properties. To that end, NP uptake and effects on the viability, phenotype, and secretory activity of DC primary cultures. Intracellular signaling pathways were explored and evaluated. Immature human and murine DCs were exposed to cationic, neutral, or anionic PLGA NPs. Particle uptake was assessed by both confocal microscopy and flow cytometry. Cell viability was then evaluated prior to the study of maturation by examination of both surface marker expression and cytokine release. Our results demonstrate that PLGA NPs are rapidly engulfed by DCs and do not exert cytotoxic effects. However, upon exposure to PLGA NPs, DCs showed phenotypes and cytokine secretion profiles consistent with maturation which resulted, at least in part, from the transient intracellular activation of mitogen-activated protein kinases (MAPKs). Interestingly, NP-specific stimulation patterns were observed since NP surface properties had a sensible influence on the various parameters measured.
Asunto(s)
Materiales Biocompatibles/toxicidad , Células Dendríticas/efectos de los fármacos , Nanopartículas/toxicidad , Fagocitosis/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/toxicidad , Animales , Materiales Biocompatibles/química , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Técnicas de Cocultivo , Citocinas/metabolismo , Células Dendríticas/inmunología , Humanos , Ratones , Ratones Endogámicos C57BL , Nanopartículas/química , Fagocitosis/inmunología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/inmunología , Propiedades de SuperficieRESUMEN
The redox-sensitive nuclear factor erythroid-derived 2-like 2 (NRF2) controls endogenous antioxidant enzymes' transcription and protects against oxidative damage which is triggered by inflammation and known to favor progression of endometriosis. Glutamate Cysteine Ligase (GCL), a target gene of NRF2, is the first enzyme in the synthesis cascade of glutathione, an important endogenous antioxidant. Sixty-one patients, with thorough surgical examination of the abdominopelvic cavity, were recruited for the study: 31 with histologically-proven endometriosis and 30 disease-free women taken as controls. Expressions of NRF2 and GCL were investigated by quantitative RT-PCR and immunohistochemistry in eutopic and ectopic endometria from endometriosis-affected women and in endometrium of disease-free women. Ex vivo stromal and epithelial cells were extracted and purified from endometrial and endometriotic biopsies to explore expression of NRF2 and GCL in both stromal and epithelial compartments by western blot. Finally, in order to strengthen the role of NRF2 in endometriosis pathogenesis, we evaluated the drop of NRF2 expression in a mouse model of endometriosis using NRF2 knockout (NRF2-/-) mice. The mRNA levels of NRF2 and GCL were significantly lower in ectopic endometria of endometriosis-affected women compared to eutopic endometria of disease-free women. The immunohistochemical analysis confirmed the decreased expression of both NRF2 and GCL in ectopic endometriotic tissues compared to eutopic endometria of endometriosis-affected and disease-free women. Immunoblotting revealed a significant decreased of NRF2 and GCL expression in epithelial and stroma cells from ectopic lesions of endometriosis-affected women compared to eutopic endometria from controls. Using a murine model of endometriosis, NRF2-/- implants were more fibrotic compared to wild-type with an increased weight and volume. These findings indicate that expression of the transcription factor NRF2 and its effector GCL are both profoundly deregulated in endometriotic lesions towards increased growth and fibrogenetic processes.
Asunto(s)
Coristoma/genética , Endometriosis/genética , Endometrio/metabolismo , Glutamato-Cisteína Ligasa/genética , Factor 2 Relacionado con NF-E2/genética , Adulto , Animales , Estudios de Casos y Controles , Coristoma/metabolismo , Coristoma/patología , Modelos Animales de Enfermedad , Endometriosis/metabolismo , Endometriosis/patología , Endometrio/patología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Fibrosis , Regulación de la Expresión Génica , Glutamato-Cisteína Ligasa/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 2 Relacionado con NF-E2/deficiencia , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Cultivo Primario de Células , Estudios Prospectivos , Células del Estroma/metabolismo , Células del Estroma/patología , Centros de Atención TerciariaRESUMEN
90Sr is one of the radionuclides released after nuclear accidents that can significantly impact human health in the long term. 90Sr accumulates mostly in the bones of exposed populations. Previous research has shown that exposure induces changes in bone physiology both in humans and in mice. We hypothesize that, due to its close location with bone marrow stromal cells (BMSCs), 90Sr could induce functional damage to stromal cells that may explain these biological effects due to chronic exposure to 90Sr. The aim of this work was to verify this hypothesis through the use of an in vitro model of MS5 stromal cell lines exposed to 1 and 10 kBq.mL-1 of 90Sr. Results indicated that a 30-minute exposure to 90Sr induced double strand breaks in DNA, followed by DNA repair, senescence and differentiation. After 7 days of exposure, MS5 cells showed a decreased ability to proliferate, changes in cytokine expression, and changes in their ability to support hematopoietic progenitor proliferation and differentiation. These results demonstrate that chronic exposure to a low concentration of 90Sr can induce functional changes in BMSCs that in turn may explain the health effects observed in following chronic 90Sr exposure.