RESUMEN
Dendritic cells (DCs) are crucial for the induction and maintenance of tumor-specific immune responses. Studies have shown that tumor-associated DCs are immunosuppressed in some human tumors. However, phenotype and function of DCs in retinoblastoma (RB) remain unclear. RB cell supernatant (RBcs) was used to treat DCs in vitro to explore the effect of RB cells on DCs. DCs were generated from peripheral blood mononuclear cells of healthy donors. On day 5 of culture, DCs were treated with RBcs for 24 h, and then purified using magnetic beads. The maturation of DCs was induced by TNF-α or LPS. After treatment with RBcs, expression of co-stimulatory molecules CD80 and CD86 was elevated in DCs, accompanied by increased production of IL-12p70, TNF-α, IL-6, IL-1β, and IL-8 but decreased production of IL-10. RBcs neither inhibited DC maturation nor promoted DC apoptosis. Moreover, RBcs-exposed DCs stimulated allogenetic T cell proliferation and T cell-derived cytokine production. These results indicate that RBcs can improve DCs' antigen presenting function and capability to activate T cells, suggesting that RB cells may have an immunostimulatory effect on DCs, and DC-based immunotherapy may be adopted in the treatment of RB.
Asunto(s)
Humanos , Antígeno B7-1 , Metabolismo , Antígeno B7-2 , Metabolismo , Línea Celular Tumoral , Proliferación Celular , Medios de Cultivo Condicionados , Farmacología , Citocinas , Metabolismo , Células Dendríticas , Alergia e Inmunología , Metabolismo , Lipopolisacáridos , Toxicidad , Neoplasias de la Retina , Metabolismo , Patología , Retinoblastoma , Metabolismo , Patología , Linfocitos T , Biología Celular , Alergia e Inmunología , Metabolismo , Factor de Necrosis Tumoral alfa , FarmacologíaRESUMEN
The expression of a soluble protein on cell surface is often desirable for study of a functional protein, wide application of a protein or investigation of protein-protein interaction. The expression of a soluble protein on the surface of a cell is often achieved by genetically linking a protein to the extra-cellular fragment of a transmembrane partner. In this study, the myc epitope was linked with N terminal of transmembrane proteins either A2TM or deltaLNGFR amplified by overlapping PCR. The plasmids expressing fusion protein were transfected into 293FT cells and the expression of target proteins was evaluated by fluorescent microscope, flow cytometry and Western blotting. The results of flow cytometry revealed that both A2TM and deltaLNGFR were expressed on the cell surface, but A2TM could only be detected with high copy number. Western blotting showed that the expression level of deltaLNGFR was very high and protein was heavily glycosylated, by contrast the expression of A2TM was hardly detected. The results indicate that glycosylated deltaLNGFR is a good candidate partner for the expression of a soluble protein on the cell surface.
Asunto(s)
Humanos , Proteínas Reguladoras de la Apoptosis , Genética , Membrana Celular , Metabolismo , Genes MHC Clase II , Genética , Antígeno HLA-A2 , Genética , Proteínas de la Fusión de la Membrana , Genética , Metabolismo , Proteínas de la Membrana , Genética , Metabolismo , Proteínas Proto-Oncogénicas c-myc , MetabolismoRESUMEN
Objective To study congenital transmission of Trichinella spiralis in mice and observe the protection of anti-Trichinella antibodies from the infected dams to challenge infection. Methods According to the gestation (fertilization), the Kunming mice were divided into two groups: the infected group after gestation and the gestated group after infection. New-born mice were cut into small pieces to separate the larvae within 1 day after birth. One-day-old offspring born to normal dams were nursed by the infected dams, slaughtered after 21 days and examined for the larvae. Serum anti-Trichinella antibody level in offspring born to the infected dams was assayed by ELISA at different time after birth, and its immune protection against challenge infection was studied. Results Out of 6 offspring born to the dams infected at 7 days after fertilization, two were found to be infected. Among other female mice which were first infected with T. spiralis and then gestated, only the offspring born to the dams fertilized at 8 and 22 days after infection were found to be infected, the infection rate of offspring was 20% (2/10) and 25%(2/8) respectively. All larvae recovered from the young were non-encapsulated. The cross-fostering experiment showed that none of 30 offspring born to normal dams were found to be infected. The serum antibody positive rate in 27 offspring born to the infected dams at 1, 7, 24, and 40 days after birth was 100%, 100%, 77.8% and 14.8%, respectively. The worm reduction rate in the offspring 40 days after birth was 62.0% after challenge infection. The worm reduction rate in mice in which sera from the offspring born to the infected dams were passively transferred was 55.7%, there was a significant difference (P