RESUMEN
We report here a robust and practical strategy for chemical protein synthesis using an o-nitrobenzyl group as a temporary protective group for an N-terminal cysteine residue of intermediate hydrazide fragments. By reinvestigating the photoremoval of an o-nitrobenzyl group, we establish a robust and reliable strategy for its quantitative photodeprotection. The o-nitrobenzyl group is completely stable to oxidative NaNO2 treatment and has been applied to the convergent chemical synthesis of programmed death ligand 1 fragment, providing a practical avenue for hydrazide-based native chemical ligation.
Asunto(s)
Cisteína , Proteínas , Cisteína/química , Ligadura , Nitrito de Sodio/químicaRESUMEN
N(2)-[alpha-O-benzyl-N-(acetylmuramyl)-L-alanyl-D-isoglutaminyl]-N(6)-trans-(m-nitrocinnamoyl)-L-lysine (muramyl dipeptide C, or MDP-C) has been synthesized as a novel, nonspecific immunomodulator. The present study shows that MDP-C induces strong cytolytic activity by macrophages on P388 leukemia cells and cytotoxic activity by cytotoxic T lymphocytes (CTLs) on P815 mastocytoma cells. Our results also indicate that MDP-C is an effective stimulator for production of interleukin-2 and interleukin-12 by murine bone marrow derived dendritic cells (BMDCs) and production of interferon-gamma by CTLs. Additionally, MDP-C increases the expression levels of several surface molecules, including CD11c, MHC class I, and intercellular adhesion molecule-1 in BMDCs. Moreover, MDP-C remarkably enhances the immune system's responsiveness to hepatitis B surface antigen (HBsAg) in hepatitis B virus transgenic mice for both antibody production and specific HBsAg T-cell responses ex vivo. Our results indicate that MDP-C is an apyrogenic, nonallergenic, and low-toxicity immunostimulator with great potential for diagnostic, immunotherapeutic, and prophylactic applications in diseases such as hepatitis B and cancers.
Asunto(s)
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Adyuvantes Inmunológicos/síntesis química , Antígenos de Superficie de la Hepatitis B/inmunología , Acetilmuramil-Alanil-Isoglutamina/efectos adversos , Acetilmuramil-Alanil-Isoglutamina/síntesis química , Acetilmuramil-Alanil-Isoglutamina/farmacología , Adyuvantes Inmunológicos/efectos adversos , Adyuvantes Inmunológicos/farmacología , Animales , Formación de Anticuerpos , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Antígeno CD11c/biosíntesis , Línea Celular Tumoral , Citotoxicidad Inmunológica , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Antígenos de Histocompatibilidad Clase I/biosíntesis , Técnicas In Vitro , Molécula 1 de Adhesión Intercelular/biosíntesis , Interleucina-12/biosíntesis , Interleucina-2/biosíntesis , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Conejos , Ratas , Ratas Wistar , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Pruebas de Toxicidad AgudaRESUMEN
1,5-Difluoro-2,4-dinitrobenzene starting material was treated via primary and/or secondary substitution with a variety of amino acids or amines and the aromatic m-dinitro groups were then reductively cyclized provide the 2-quinoxalinol analogs. The conditions for 1,5-dialkylamino-2,4-dinitrobenzene reduction have been systematically studied and optimized in solution. Three effective methods are described for the high-throughout generation of 2-quinoxalinol analogs.
Asunto(s)
Bioquímica/métodos , Técnicas Químicas Combinatorias , Quinoxalinas/síntesis química , SolucionesRESUMEN
A parallel solution-phase synthesis of 2-quinoxalinol analogues is described. The key step-simultaneous reductions of m-Ar(NO2)2 to m-Ar(NH2)2 was investigated extensively. We obtained preliminary pharmacological activity of those analogues for the inhibition of LPS-induced TNF-alpha release on mouse macrophage in vitro. Two compounds revealed inhibitory activity, with IC50 values of 0.40 microM (7-amino-6-[(3-methoxypropyl)amino]-3-methyl-2-quinoxalinol) and 2.2 microM (7-amino-6-[(3-butoxypropyl)amino]-3-methyl-2-quinoxalinol), respectively.
Asunto(s)
Soluciones Farmacéuticas , Factor de Necrosis Tumoral alfa , Animales , Lipopolisacáridos , Macrófagos , Ratones , SolucionesRESUMEN
A new "Meshed-Bag Gathered-Bunch" technology for the solid-phase synthesis of chemical libraries was developed. Using such technology, we synthesized muramyl dipeptide mimetics including derivatives at the N- and C-terminus, cyclic muramyl dipeptide mimetics, muramyl dipeptide and Tuftsin's analogue conjugates. The advantages of such a method include ease of manufacture, low unit cost of production, the physical encoding method, and the compatibility with both parallel and "split-mix" approaches.