RESUMEN
Both active and passive immunization strategies against Staphylococcus aureus have thus far failed to show efficacy in humans. With the attempt to develop an effective S. aureus vaccine, we selected five conserved antigens known to have different roles in S. aureus pathogenesis. They include the secreted factors α-hemolysin (Hla), ess extracellular A (EsxA), and ess extracellular B (EsxB) and the two surface proteins ferric hydroxamate uptake D2 and conserved staphylococcal antigen 1A. The combined vaccine antigens formulated with aluminum hydroxide induced antibodies with opsonophagocytic and functional activities and provided consistent protection in four mouse models when challenged with a panel of epidemiologically relevant S. aureus strains. The importance of antibodies in protection was demonstrated by passive transfer experiments. Furthermore, when formulated with a toll-like receptor 7-dependent (TLR7) agonist recently designed and developed in our laboratories (SMIP.7-10) adsorbed to alum, the five antigens provided close to 100% protection against four different staphylococcal strains. The new formulation induced not only high antibody titers but also a Th1 skewed immune response as judged by antibody isotype and cytokine profiles. In addition, low frequencies of IL-17-secreting T cells were also observed. Altogether, our data demonstrate that the rational selection of mixtures of conserved antigens combined with Th1/Th17 adjuvants can lead to promising vaccine formulations against S. aureus.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Infecciones Estafilocócicas/prevención & control , Vacunas Estafilocócicas/química , Receptor Toll-Like 7/química , Absceso/patología , Inmunidad Adaptativa , Animales , Antibacterianos/química , Anticuerpos Antibacterianos/inmunología , Antígenos/inmunología , Humanos , Ratones , Modelos Animales , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus , Células TH1/inmunologíaRESUMEN
A 78-year-old woman who had been treated for two years with ITCZ for chronic pulmonary aspergillosis associated with prior pulmonary tuberculosis was admitted to our hospital because of general fatigue and hemosputum along with deterioration of her chest radiographic findings. Mycobacterium abscessus had been isolated once from her sputum one year before admission. We performed fiberoptic bronchoscopy (FOB) in order to help establish a final diagnosis. Sputum aspirated from her bronchus on FOB stained positive for acid-fast bacilli and was negative for Tbc and MAC using PCR. From these results, we diagnosed the patient with pulmonary M. abscessus infection. Chemotherapy with AMK, IPM/cs, and CAM was initiated. Because her symptoms rapidly improved, we switched the chemotherapy to long-term oral CAM and LVFX, and she has been in a good condition at 12 months after the initiation of the therapy. Recently, subtypes of M. abscessus complex, such as M. massiliense, have been recognized, which are more sensitive to chemotherapy. Considering the good response to therapy, there is a possibility that is the patient in the current case had a M. massiliense infection.
Asunto(s)
Antibacterianos/administración & dosificación , Enfermedades Pulmonares/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Administración Oral , Anciano , Amicacina/administración & dosificación , Antibacterianos/uso terapéutico , Cilastatina/administración & dosificación , Combinación Cilastatina e Imipenem , Claritromicina/administración & dosificación , Combinación de Medicamentos , Femenino , Humanos , Imipenem/administración & dosificación , Levofloxacino/administración & dosificación , Micobacterias no TuberculosasRESUMEN
BACKGROUND AND OBJECTIVE: The usefulness of two tests in the serodiagnosis of chronic pulmonary aspergillosis (CPA) was compared. The tests were the serum Aspergillus galactomannan antigen test (Platelia (R) Aspergillus) by enzyme-linked immunoassay (EIA) using old and new cut-off indexes, and the Aspergillus precipitating antibody test. METHODS: Both Aspergillus-precipitating antibody and Platelia Aspergillus EIA positivity were measured in the sera of 28 patients at the time of diagnosis of CPA. RESULTS: Serum Aspergillus precipitating antibody positivity was 89.3% (25/28) in CPA patients. Serum Platelia Aspergillus EIA positivity was 21.4% (6/28) using the old cut-off index (> or =1.5) and 50% (14/28) using the new cut-off index (> or =0.5)-still less than that for Aspergillus precipitating antibody. Three of the 28 CPA patients had positive reactions in the Platelia Aspergillus EIA using the old cut-off index but not in the Aspergillus precipitating antibody test. Positivity for (1,3) beta-d glucan was 15.4%, and that for culture on CHROMagar Candida was 17.9%. One patient with pulmonary actinomycosis had a false-positive reaction in the Platelia Aspergillus test with the new cut-off index. CONCLUSIONS: For the diagnosis of CPA, Aspergillus precipitating antibody testing is more sensitive than the Platelia Aspergillus EIA, even with the new cut-off index. False-positive reactions are observed with the Platelia Aspergillus EIA in patients with conditions such as pulmonary actinomycosis. Results should be interpreted with care when patients are positive for the Platelia Aspergillus EIA but negative for Aspergillus precipitating antibody.
Asunto(s)
Anticuerpos Antifúngicos/sangre , Antígenos Fúngicos/sangre , Aspergillus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Pruebas de Precipitina/métodos , Aspergilosis Pulmonar/diagnóstico , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aspergilosis Pulmonar/sangre , Aspergilosis Pulmonar/inmunología , Estudios Retrospectivos , Sensibilidad y Especificidad , Pruebas Serológicas/métodosRESUMEN
BACKGROUND: Nuclear factor kappaB (NFkappaB) is a transcription factor which is importantly implicated in cancer cell growth. In a previous report, we confirmed that lung cancer cell growth was suppressed significantly by the blockade of NFkappaB function. In this study the combination effect of chemotherapy and inhibition of NFkappaB on the human lung cancer cell line, NCI-H460, in vitro and in vivo was investigated. MATERIALS AND METHODS: In the in vitro experiment, 50% of cell growth inhibitory concentrations (IC50) of chemotherapy agents were determined alone or when combined with adenovirus mediated IkappaBalpha gene transfer. Annexin-V/PI stain and caspase 3 activity measurement were used to detect the apoptosis caused by treatment. In the in vivo experiment, the tumor growth suppressive effect of combination treatment was evaluated for tumor-bearing mice. NFkappaB, p53 and VEGF expression in the tumors were also analyzed immunohistologically. RESULTS: Several chemotherapy agents, including paclitaxel, showed lower IC50s when combined with AdIkappaBalpha infection in vitro. Apoptosis through activation of the caspase 3 pathway was enhanced by the combination treatment. For established NCI-H460 tumors, combined treatment significantly inhibited tumor growth. Immunohistochemical staining showed increased expression of p65 after paclitaxel treatment, while paclitaxel in combination with AdIkappaBalpha intratumoral injection eliminated this expression accompanied by the slightly reduced expression of VEGF, with stable p53 status. CONCLUSION: A combination of chemotherapy and IkappaBalpha could inhibit tumor growth effectively by blocking the expression of NFkappaB and inducing apoptosis. Moreover, it might allow reduction of the dose of chemotherapy agents and provide benefit for clinical application.
Asunto(s)
Genes p53 , Proteínas I-kappa B/genética , Neoplasias Pulmonares/terapia , FN-kappa B/genética , Adenoviridae/genética , Animales , Apoptosis , Caspasa 3/metabolismo , Línea Celular Tumoral , Terapia Combinada , Resistencia a Antineoplásicos , Técnicas de Transferencia de Gen , Humanos , Ratones , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Paclitaxel/farmacología , Transfección , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Nuclear factor kappaB (NFkappaB) is an inducible and ubiquitously expressed transcription factor which is involved in cell survival, differentiation and growth and, thus, has also been implicated in tumor formation and development. Research on the effect of NFkappaB in inhibiting cancer cell growth, however, remains controversial. MATERIALS AND METHODS: We investigated the effects of overexpressed IkappaBalpha on the proliferation of the human lung cancer cell line H460 in vitro and in vivo using IkappaBalpha-expressing adenovirus. RESULTS: The results suggested that the infection of AdIkappaBalpha blocked NFkappaB activity in H460 cells and significantly inhibited cell proliferation by inducing apoptosis. An in vivo study showed the tumor incidence to be significantly lower in mice implanted with H460 cells infected with AdIkappaBa. For established H460 tumor, the intratumoral injection of AdIkappaBalpha also inhibited the tumor growth due to both a blockade of the NFkappaB activity and an inhibition of the VEGF expression. CONCLUSION: Adenovirus-mediated IkappaBalpha gene transfer is a promising cancer treatment strategy.
Asunto(s)
Terapia Genética/métodos , Proteínas I-kappa B/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , FN-kappa B/antagonistas & inhibidores , Adenoviridae/genética , Animales , Apoptosis/genética , Caspasa 3 , Caspasas/metabolismo , Procesos de Crecimiento Celular/genética , Línea Celular Tumoral , Humanos , Proteínas I-kappa B/biosíntesis , Inmunohistoquímica , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Neovascularización Patológica/terapia , Transfección , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Vascular endothelial growth factor (VEGF) is well known to be produced by many human tumors, and it also plays an important role in tumor neovasculature formation. In addition to angiogenesis promotion, recent basic research has shown that VEGF has another function that allows it to inhibit dendritic cell (DC) maturation. However, very little is known about VEGF-dependent DC inhibition in a clinical setting. In this study, we analyzed the immunohistochemical expression of VEGF, microvessel density (MVD), and intratumoral DC infiltration in 132 surgically resected lung cancer specimens. We also evaluated the influence of these factors on their survival by a multivariate statistical analysis. VEGF expression was positively related to MVD (P = 0.0003) and negatively related to the degree of DC infiltration (P = 0.0232). A multivariate analysis also showed the VEGF expression, MVD, and DC infiltration to be independent prognostic factors. Moreover, we also accurately analyzed patient prognoses using the double stratification method for determining VEGF expression and DC infiltration. The patient group with a high VEGF expression/low DC infiltration showed a worse prognosis (P < 0.0001), whereas the group with a low VEGF expression/high DC infiltration had a better prognosis (P = 0.0001).
Asunto(s)
Células Dendríticas/patología , Factores de Crecimiento Endotelial/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Neoplasias Pulmonares/diagnóstico , Linfocinas/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/patología , Células Dendríticas/citología , Femenino , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/patología , Masculino , Microcirculación , Persona de Mediana Edad , Análisis Multivariante , Neoplasias/irrigación sanguínea , Pronóstico , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
Staphylococcus aureus is a major cause of human disease, responsible for half a million infections and approximately 20,000 deaths per year in the United States alone. This pathogen secretes α-hemolysin, a pore-forming cytotoxin that contributes to the pathogenesis of pneumonia. α-hemolysin injures epithelial cells in vitro by interacting with its receptor, the zinc-dependent metalloprotease ADAM10 (ref. 6). We show here that mice harboring a conditional disruption of the Adam10 gene in lung epithelium are resistant to lethal pneumonia. Investigation of the molecular mechanism of toxin-receptor function revealed that α-hemolysin upregulates ADAM10 metalloprotease activity in alveolar epithelial cells, resulting in cleavage of the adherens junction protein E-cadherin. Cleavage is associated with disruption of epithelial barrier function, contributing to the pathogenesis of lethal acute lung injury. A metalloprotease inhibitor of ADAM10 prevents E-cadherin cleavage in response to Hla; similarly, toxin-dependent E-cadherin proteolysis and barrier disruption is attenuated in ADAM10-knockout mice. Together, these data attest to the function of ADAM10 as the cellular receptor for α-hemolysin. The observation that α-hemolysin can usurp the metalloprotease activity of its receptor reveals a previously unknown mechanism of pore-forming cytotoxin action in which pathologic insults are not solely the result of irreversible membrane injury and defines ADAM10 inhibition as a strategy to attenuate α-hemolysin-induced disease.