RESUMO
BACKGROUND: The expression of the scavenger receptor for advanced glycation end products (RAGE) and various ligands of RAGE correlate significantly with cancer progression. However, the mechanism of RAGE/sRAGE-induced cancer cell activation and ligand usage remain largely unknown. METHODS: Androgen-independent, highly invasive, as well as androgen-dependent, non-invasive human prostate carcinoma (CaP) cells were investigated for their interaction with the soluble form of RAGE (sRAGE). Using neutralizing antibodies and soluble proteins, the ligand for RAGE was identified on CaP cells and ligand binding with sRAGE was biochemically characterized. RESULTS: Both androgen-independent, highly invasive and androgen-dependent, non-invasive CaP cells interacted with immobilized sRAGE in a surprisingly strong manner. Using C-terminal truncation variants of RAGE we identified the V domain being responsible for the adhesion of CaP cells to sRAGE. Moreover, we demonstrate that this adhesion cannot be blocked by S100B or neutralizing antibodies against beta integrins, or amphoterin. However, the CaP cell-RAGE interaction was inhibited with either AGE-modified proteins, or with neutralizing antibodies against AGE or RAGE. Despite similar binding kinetics between AGE-modified BSA and different RAGE domains, only applying an excess of sRAGE, but not the VC1 or V domain of RAGE, was able to block the CaP cell-RAGE interaction. CONCLUSIONS: We identified AGEs as the ligand for RAGE on both invasive and non-invasive prostate cancer cells.
Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Imunológicos/metabolismo , Anticorpos Bloqueadores/farmacologia , Sítios de Ligação , Ligação Competitiva , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Produtos Finais de Glicação Avançada/química , Proteína HMGB1/imunologia , Humanos , Ligantes , Masculino , Fatores de Crescimento Neural/metabolismo , Neoplasias da Próstata/imunologia , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/química , Receptores Imunológicos/imunologia , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/metabolismoRESUMO
Dendritic cell (DC)-based immunotherapy has been hampered by the lack of suitable methods for antigen delivery. Here, we use biodegradable poly(D,L-lactide-co-glycolide) microspheres (PLGA-MS) as carriers of peptides and proteins for antigen delivery to human monocyte-derived DC (MoDC). Compared to soluble proteins, MHC classes I and II-restricted presentation of PLGA-MS-encapsulated proteins and peptides by MoDC was markedly prolonged and proteins were presented 50-fold more efficiently on class I molecules. The vaccination of mice with DC loaded with PLGA-MS-encapsulated proteins raised strong and persisting cytotoxic T cell responses. In conclusion, antigen delivery via PLGA-MS markedly enhanced the duration of antigen presentation by human MoDC and the potency of DC-based vaccination.
Assuntos
Células Dendríticas/imunologia , Ácido Láctico , Microesferas , Peptídeos/imunologia , Ácido Poliglicólico , Polímeros , Proteínas/imunologia , Animais , Apresentação de Antígeno , Linhagem Celular , Testes Imunológicos de Citotoxicidade , Preparações de Ação Retardada , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Peptídeos/administração & dosagem , Peptídeos/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteínas/administração & dosagem , Proteínas/metabolismo , Linfócitos T Citotóxicos/imunologia , Toxoide Tetânico/administração & dosagem , Toxoide Tetânico/imunologia , Toxoide Tetânico/metabolismo , Vacinação/métodos , Proteínas da Matriz Viral/administração & dosagem , Proteínas da Matriz Viral/imunologia , Proteínas da Matriz Viral/metabolismoRESUMO
BACKGROUND: Dendritic cell (DC)-based vaccination has been investigated as immunotherapy for several types of cancer. A potential drawback to vaccination with autologous monocyte-derived DCs (MoDCs) could be that MoDCs from patients are functionally impaired. In case of androgen-independent prostate cancer (CaP), the cancer itself, diverse prior therapies, and the hormone manipulation may affect the immune system. METHODS: MoDCs from patients suffering from androgen-independent CaP were generated according to a clinically applicable protocol to evaluate the phenotype, maturation capacity, migration, and T-cell stimulation of these cells compared with those generated from tumor-free donors. RESULTS: MoDCs generated from CaP patients could be fully matured and efficiently migrated towards the chemokine CCL21. They had a strong potency to activate allogeneic CD4+ and CD8+ T-cells and to present antigens to specific CTL. CONCLUSIONS: Our data suggest that MoDCs from patients with androgen-independent CaP are functionally intact and hence qualify as cellular vaccines for immunotherapy of advanced stage CaP.