RESUMEN
We examined the effect of semisynthetic trehalose-6,6 '-dimycolate (TDM) and its synthetic stereoisomeric derivatives (trehalose 6,6'-dicorynomycolates; TDCMs) prepared in oil-in-water (o/w) emulsion on inhibition of lung metastasis produced by highly metastatic murine tumour cells, colon 26-M3.1 carcinoma and B16-BL6 melanoma cells, using experimental and spontaneous metastasis models. Intravenous (i.v.) administration of TDM (100 microg/mouse) 1, 3 or 8 days before tumour inoculation significantly inhibited lung metastasis of colon 26-M3.1 cells, in a dose-dependent manner. Single administration of TDM 1 day after tumour inoculation also showed the therapeutic effect on experimental lung metastasis of colon 26-M3.1 cells. Similarly, multiple administrations of TDM after tumour inoculation resulted in a significant inhibition of spontaneous lung metastasis of B16-BL6 cells (on day 35), although it showed no effect on suppression of tumour growth (on day 21). In comparison of toxicity in vivo among TDM and four TDCMs such as TDCM(2R,3R), TDCM(2S,3R), TDCM(2R,3S) and TDCM(2S,3S), all of the TDCMs appeared to be less toxic than TDM itself. Furthermore, all of the TDCMs were prophylactically as well as therapeutically active for inhibition of lung metastasis of both colon 26-M3.1 and B16-BL6 tumour cells, showing higher inhibitory activity than that of TDM. In particular, TDCMs induced a marked suppression of the growth of B16-BL6 tumour cells in vivo. These results suggest that systemic administration of TDM as well as TDCMs led to inhibition of tumour metastasis and TDCMs are more potential to suppress tumour growth and inhibit tumour metastasis than TDM.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antineoplásicos/farmacología , Factores Cordón/farmacología , Neoplasias Pulmonares/patología , Animales , Carcinoma Pulmonar de Lewis/patología , Neoplasias del Colon/patología , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Modelos Químicos , Metástasis de la Neoplasia , EstereoisomerismoRESUMEN
Dialysis-related amyloidosis (DRA) is a major complication of long-term hemodialysis patients. The onset of arthropathy is frequently preceded by carpal tunnel syndrome, but the early non-invasive diagnosis of DRA remains unclear. beta 2-microglobulin amyloid deposits in joint synovia and soft tissue precede radiological abnormalities. Magnetic resonance imaging (MRI) may play a more important role in the early diagnosis of DRA, because it allows direct visualization of synovitis and deposition of abnormal soft tissue. The purpose of this study was to evaluate the usefulness of MRI of the wrist for the early diagnosis of DRA. The study included 72 patients (male 37, female 35) undergoing hemodialysis from initiation to 20 years. The patients were examined by MR images of synovitis, deposition of abnormal soft tissue and cystic bone lesions at the wrists. Normal MR images of synovia and soft tissue were defined in 6 control subjects (2 normal 4 non-dialysis patients). Synovitis of the carpal bones was found in 23% of the patients at the start of hemodialysis. Deposition of abnormal soft tissue in the carpal canal and cystic bone lesions were detected after 1 and 2 years of hemodialysis, respectively. All findings were increased significantly with an increasing duration of dialysis. Synovitis was present in 90% of the patients with deposition of abnormal soft tissue, and in 80% of the patients with cystic bone lesions. beta 2-microglobulin value was significantly higher in patients with synovitis, deposition of abnormal soft tissue and cystic bone lesions than in patients without these findings. Our experience suggest that synovitis examined by MRI of the wrists is useful for the early diagnosis of DRA. Thereby, intensive follow-up and management of DRA are required in patients with synovitis at the start of hemodialysis.
Asunto(s)
Amiloidosis/diagnóstico , Imagen por Resonancia Magnética , Diálisis Renal/efectos adversos , Muñeca/patología , Síndrome del Túnel Carpiano/diagnóstico , Femenino , Humanos , Masculino , Líquido Sinovial/metabolismo , Microglobulina beta-2/metabolismoRESUMEN
In a previous study, we demonstrated that a lipophilic derivative of muramyl dipeptide [MDP-Lys(L18)] augmented antibody response to recombinant human hepatitis B surface antigen (rhHBsAg) when it was co-immunized with rhHBsAg solubilized in PBS. Here, we examined adjuvant activity of two bacterial cell-derived adjuvants such as Bacillus Calmette-Guérin cell wall skeleton (BCG-CWS) and trehalose-6,6'-dimycolate (TDM), to enhance immunogenicity of rhHBsAg, comparing their activity with that of MDP-Lys(L18). In an animal model where mice were immunized subcutaneously (s.c.) with rhHBsAg (25 micrograms/mouse) admixed with 100 micrograms/mouse of BCG-CWS (Vac/BCG-CWS) or 50 micrograms/mouse of TDM (Vac/TDM) in o/w emulsion formulation, both mice immunized with Vac/BCG-CWS and Vac/TDM showed higher antibody titres to HB antigen than those of mice immunized with the recombinant vaccine alone. The activity of BCG-CWS and TDM to enhance antibody induction seemed to be almost the same with that of MDP-Lys(L18). Furthermore, the enhanced antibody response raised by these adjuvants was shown to be due to high titres of HB antigen-specific IgG1. In addition, the activity of these three adjuvants to enhance antibody response was shown to be higher than that of the present clinical vaccine, aluminium hydroxide-attached rhHBsAg (rhHBsAg-alum). In an analysis of delayed-type hypersensitivity (DTH) reaction where mice were immunized with rhHBsAg admixed with or without each adjuvant in o/w emulsion and followed by intrafootpad (i.f.) injection of rhHBsAg 4 weeks after immunization, mice immunized with Vac/BCG-CWS and Vac/TDM as well as Vac/MDP-Lys(L18) showed a significant increment of swelling reaction. These results suggest that BCG-CWS, TDM and MDP-Lys(L18) are potential adjuvants to enhance the immunogenicity of rhHBsAg to induce humoral and cellular responses.
Asunto(s)
Adyuvantes Inmunológicos , Anticuerpos contra la Hepatitis B/biosíntesis , Vacunas contra Hepatitis B/inmunología , Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Acetilmuramil-Alanil-Isoglutamina/inmunología , Animales , Vacuna BCG/inmunología , Pared Celular/inmunología , Factores Cordón/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Humanos , Hipersensibilidad Tardía/inmunología , Isotipos de Inmunoglobulinas/inmunología , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes/inmunologíaRESUMEN
We examined the activity of bovine lactoferricin (Lfcin-B), a peptide derived from a bovine milk protein lactoferrin (LF-B), to induce apoptosis in THP-1 human monocytic leukemic cells. Treatment with Lfcin-B at up to 50 micrograms/ml induced cell death in THP-1 cells in dose- and time-dependent manner, showing apparent morphological changes, hypodiploid forms of genomic DNA and apoptotic DNA fragmentation, whereas LF-B was inactive even at a high dose (500 micrograms/ml). The apoptosis-inducing effect of Lfcin-B increased with reduction of serum concentration, but was inhibited by addition of Zn2+, a inhibitor of Ca2+/Mg(2+)-dependent endonucleases in a dose-dependent manner. Furthermore, Lfcin-B-induced apoptosis in THP-1 cells was completely abolished by addition of antioxidants such as N-acetyl-L-cysteine (NAC) and glutathione (GSH), but not by various cytokines and mitogen which can activate monocytic cells. In addition, THP-1 cells treated with Lfcin-B, but not LF-B, showed high levels of intracellular reactive oxygen species (ROS) from the early period (20 min) of Lfcin-B treatment. And the production of ROS by Lfcin-B was dependent upon the dose of Lfcin-B added. These results suggested that Lfcin-B, a LF-B-derived peptide, but not LF-B itself, is able to induce apoptosis in THP-1 human monocytic tumor cells, and that its apoptosis-inducing activity is related to the pathway mediated by production of the intracellular ROS and activation of Ca2+/Mg(2+)-dependent endonucleases.