1. |
|
|
2. |
- Eriksson, Kristina, 1962, et al.
(författare)
-
Coupling of antigen to cholera toxin for dendritic cell vaccination promotes the induction of MHC class I-restricted cytotoxic T cells and the rejection of a cognate antigen-expressing model tumor.
- 2004
-
Ingår i: European journal of immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 34:5, s. 1272-81
-
Tidskriftsartikel (refereegranskat)abstract
- We previously demonstrated that cholera toxin (CT) is highly efficient as a combined carrier and adjuvant for dendritic cell (DC) vaccination, inducing strong Th1-dominated B cell and CD4(+) T cell responses. In this study we show that vaccination with DC pre-pulsed ex vivo with CT-conjugated OVA (OVA-CT) gives rise to OVA-specific CD8(+) T cells that produce IFN-gamma and are cytotoxic for OVA-expressing E.G7 tumor cells both in vitro and in vivo. The induction of specific CD8(+) CTL by OVA-CT-treated DC was associated with enhanced presentation of OVA peptide (SIINFEKL) on MHC class I in combination with an overall activation of the pulsed DC. Vaccination of mice with OVA-CT-pulsed DC resulted in rejection of already established MHC class I-positive, MHC class II-negative, OVA-expressing E.G7 tumors in an antigen-specific, CD8(+) T cell-dependent fashion and was associated with high numbers of tumor-infiltrating CD8(+) T cells. Conjugation of antigen to CT facilitated DC uptake of the linked antigen through the GM1 receptor-binding B subunit and induced strong activation-maturation signals through the biologically active A subunit. These results have interesting implications for DC vaccination aimed at inducing CTL immune responses.
|
|
3. |
- Sun, Jia-Bin, 1948, et al.
(författare)
-
Vaccination with dendritic cells pulsed in vitro with tumor antigen conjugated to cholera toxin efficiently induces specific tumoricidal CD8+ cytotoxic lymphocytes dependent on cyclic AMP activation of dendritic cells.
- 2004
-
Ingår i: Clinical immunology (Orlando, Fla.). - : Elsevier BV. - 1521-6616. ; 112:1, s. 35-44
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated the development of CD8+ tumor-specific cytotoxic lymphocytes (CTL) and protection against tumor growth after vaccination with bone marrow-derived dendritic cells (DC) pulsed with a model protein ovalbumin conjugated to cholera toxin (OVA-CT) in B6 mice using E.G7 tumor cells expressing OVA(257-264) peptide (SIINFEKL) as target cells in vitro and in vivo. Vaccination with OVA-CT-pulsed DC concurrently induced strong CTL in vitro activity and anti-E.G7 tumor protection in vivo in WT, NK-depleted and CD4-deficient mice as well as in IL-12-/- and IFN-gamma-/- mice but not in CD8-deficient mice. Importantly, activation of CTL by OVA-CT-pulsed DC was dependent on CT-induced activation of adenylate cyclase and increased cAMP production by DC associated with increased expression of MHC class I and co-stimulatory molecules (CD80, CD86 and CD40). These results show that vaccination with DC pulsed with antigens (Ag) conjugated to CT induces a strong CTL response and suggest that conjugation of tumor Ag to CT for DC vaccination represents a promising approach for tumor vaccination and immunotherapy.
|
|
4. |
|
|
5. |
|
|
6. |
|
|
7. |
|
|
8. |
|
|
9. |
- Yuan, Bin, et al.
(författare)
-
Dose-effect relationship of apoptosis induced by fission-neutron in murine thymocytes
- 2000
-
Ingår i: Chinese Journal of Radiological Medical Protection. ; 20, s. 87-87
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To investigate the effectiveness of high LET fission-neutron to induce apoptosis in murine thymocytes and to compare it with that of low LET 60Co γ-ray. Methods Apoptosis induction was studied qualitatively by light and transmission electron microscopy and DNA gel electrophoresis,also quantitatively by flow cytometry(FCM) and diphenylamine (DPA)methods. Results DNA ladders of murine thymocytes were detectable,the typical apoptosis of thymocytes could be observed morphologically by means of light and electron microscopy at 6 h after fission-neutron irradiation with doses ranging from 0.5 to 5.0 Gy,meanwhile the percentages of apoptosis increased with increasing doses.After exposure to γ-rays with doses ranging from 1.0 to 30 Gy,the expermiental results were similar to those from neutron radiation.The incidence of apoptosis peaked at about 20 Gy,the percentages did not increase further when doses increased. Conclusion Apoptosis of murine thymocytes can be induced when mice are exposed to either fission-neutron (0.5-5.0 Gy) or to γ-ray (1-30 Gy).Although the relationship between apoptosis and radiation doses is similar,the percentage of apoptosis induced by neutron irradiation is higher than that induced by γ-irradiation.The RBE values of fission-neutron for inducing apoptosis murine thymocytes are 2.09 (by FCM method) and 2.37 (by DPA method),respectively.These results also suggest that fission-neutron-induced murine immune tissue is more severe than that induced by γ-rays at several hours post-irradiation and this might be the basis for heavy damage to immune tissues induced by fission-neutron-irradiation in later period.
|
|