A preliminary study on the biological characteristics and function of tolerogenic dendritic cells induced by tacrolimus / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the biological characteristics and the immuno-suppression function of tolerogenic dendritic cells (tDC) induced by tacrolimus.</p><p><b>METHODS</b>Human monocytes derived from peripheral blood were cultured in the cGMP-compliant CellGro DC medium supplemented with GM-CSF and IL-4 to obtain dendritic cells (DCs), and 0.1 μmol/L immunosuppressive drug tacrolimus was added to the culture medium at the third and fifth day to obtain tDCs. The molecular markers of them and the livability were assayed by flow cytometry. Then the tolerance functionality of tDCs induced by many agents and these tDCs modulated allogeneic CD4 T cells was determined via CFSE proliferation assay. And the research also analyzed the biological characters and immunosuppression function of tDCs induced by tacrolimus after storing.</p><p><b>RESULTS</b>tDCs induced by tacrolimus exhibit a typical tolerogenic phenotype, whose level of costimulatory molecules CD80, CD83, CD86 and HLA-DR is (2.95 ± 1.32)%, (2.33 ± 1.60)%, (90.02 ± 7.42)% and (91.80 ± 6.18)%, respectively. It's survival rate was (85.2 ± 4.72)%. And immunosuppressive drugs didn't influence the differentiation of tDCs from monocytes. tDCs induced by immunosuppressive drugs dexamethasone, cyclosporin A and tacrolimus had lower immunogenic than control DCs as CD4+ T proliferation rate of tDCs induced by tacrolimus is 0.42% and could not primed allogeneic CD4+ T cells proliferation. Functional analyses showed that tDCs induced by tacrolimus can more effectively suppressed mature DC-induced T cell proliferation than other tDCs, whose inhibition rate can reach (67.01 ± 19.73)%. Importantly, tDCs induced by tacrolimus had phenotypical and functional stability after storing.</p><p><b>CONCLUSION</b>tDCs induced by tacrolimus with tolerance functionality are a promising cellular therapeutic for immunomodulation.</p>

Advances on the methods of enhancing the immunological functions of exosomes / 白血病·淋巴瘤

Exosomes are membrane vesicles released into the extracellular environment upon exocytic fusion of multivesicular bodies with the cell surface. As a result of initial studies showing that exosomes display signal and immune factors,a particular interest has emerged in their use as a cellular vehicles for stimulation of immune responses in vivo.In recent years,on the base of the knowledge of the biological properties and functions, exosomes have been rebuilt and bound to different kinds of immunological stimulators as a result to enhanced antitumor funotions.In this paper,the related methods,immunological stimulators and the properties of man-made exosomes are mainly reviewed.

Inhibition of MHCⅡExpression on Human Dermal Fibroblast Through CⅡTA Anti-sense RNA / 中华皮肤科杂志

Objective To investigate the feasibility of using anti-sense RNA against classⅡmajor histocompatibility complex(MHCⅡ)transactivator(CⅡTA),which might regulate MHCⅡexpression,to suppress the relative immune response.Methods Stable transfectants of dermal fibroblasts with pDarⅡ(pDarⅡ-D)were tested for the expression of classic MHCⅡ(HLA-DR,-DP,-DQ)antigens induced with recombinant human interferon-gamma(IFN-?).mRNA abundance of CⅡTA,and classic MHCⅡwas mea-sured by RT-PCR.IL-2mRNA expressed in T cells,stimulated by transfected dermal fibroblasts,was de-termined by mixed lymphocyte reaction.Results When induced with IFN-?,the expression of HLA-DR and-DP antigens on pDarⅡ-D was reduced by95.63%and87.89%,respectively.Meanwhile,the mRNA contents of CⅡTA and classic MHCⅡwere decreased significantly(P

In vitro biological activity of anti-C II TA hammerhead ribozyme--a novel approach for autoimmune diseases / 华中科技大学学报（医学）（英德文版）

This study investigated the feasibility of using an hammerhead ribozyme against C II TA, a major regulator of MHC II antigens, to repress the expression of MHC II molecules on Hela cells. A hammerhead ribozyme (Rz464) specific to 463-465 GUC triplet of C II TA and its target gene were transcribed, then mixed up and incubated in vitro. The cleavage products were analyzed by PAGE and silver-staining. Rz464 was then inserted into the pIRES2-EGFP vector (pRz464). Stable transfectants of Hela with pRz464 were tested for class II MHC induction by recombinant human interferon-gamma (IFN-gamma). mRNA of C II TA was measured by RT-PCR. Our results showed that Rz464 could exclusively cleave C II TA RNA. When induced with IFN-gamma, the expression of HLA-DR, -DP, -DQ on pRz464+ Hela was induced, and the mRNA content of C II TA decreased too. It is concluded that Rz464 could inhibit C II TA and thus the family of genes was regulated by C II TA:MHC II molecules. These results provided insight into the future application of Rz464 as a new nucleic acid drug against auto-immune diseases.

Effect of ~(137)Cs-irradiation on the components of buffy coat / 中国输血杂志

Objective To investigate the changes of buffy coat components after 25Gy 137Cs-irradiation.Methods Lymphocyte proliferation was detected by MTT,the fluorescent intensity of neutrophils was measured as phagocytotic rate by flow cytometry,O2-release was determined by cytochrome C reduction,and cytokine production pre-and post-irradiation was detected by ELISA.Results 25Gy is adequate to inactivate T cells.The percentages of phagocytosis of E.coli before and after irradiation were of no significant difference.The release of O2-increased significantly and monocytes maintained the ability to produce cytokines after irradiation.Conclusion Radiation does affect the components of buffy coat,and neutrophils isolated should be transfused as early as possible.

In vitro induction of p210~(Bcr-Abl) protein-specific cytotoxic T cell responses using 562 cell total RNA transfected human dendritic cells / 中国输血杂志

Objective To investigate whether human monocyte-derived dendritic cells (DCs) can express p210 Bcr-Abl protein and induce antigen-specific CTL responses in vitro after transfection with total RNA of K562 cells (K562-RNA).Methods Immature DCs were derived from human peripheral blood monocytes after 5 day incubation in the presence of GM-CSF and IL-4. The cells were then transfected with K562-RNA using electroporation or DOTAP lipofection. To verify the successful transfection of DCs with K562-RNA, Bcr-Abl fusion gene expression was determined by RT-PCR and Western blot. The immune phenotypes of the DCs were analyzed by flow cytometry. CTL cytotoxicity was assayed by propidium iodide (PI) stain and flow cytometry. The amount of DCs, CD1a expression and purity of DCs were measured by FACS.Results Bcr-Abl fusion gene appeared in the DCs after transfection with K562 cell total RNA. But 24 hours later, the Bcr-Abl mRNA from the K562-RNA transfected DCs disappeared, while the cells were expressing p210 Bcr-Abl protein. The transfected DCs could significantly promote T lymphocytes to kill the target K562 cells. We found that PBMC can be induced to DC in culture medium containing human plasma, suggesting a potential for clinical application.Conclusion Human dendritic cells transfected by K562 total RNA can induce effective p210 Bcr-Abl protein-specific immune responses, which might broaden the spectrum of possible DC-based clinical applications.

Study on the expansion and the cytokine releasing of human NKT cells in vitro / 中国输血杂志

Objective To expand the NKT cells in vitro and to determine the cytokine releasing of NKT cells during proliferation.Methods Several kind of methods were established to expand TCRV ?24 +/TCRV ?11 + NKT cells from PBMC or purified T lymphocyte.The levels of IL 4,IFN ?and TNF ? of NKT cells were determined by flow cytometry.Results After 19 days' expansion,the largest number of NKT cells increased (23.0?16.7)?10 3 times and the largest ratio of NKT cells to total T lymphocyte was (25.5?7.2)%.The ratio of TCRV ?11 + NKT cells that secreted IL 4,IFN ?and TNF ? was higher than the TCRV?11 T lymphocytes.Conclusion TCRV ?24 +/TCRV ?11 + NKT cells can be expanded in vitro with ? Galcer presented by CD 1d molecule.The NKT cells can also be expanded from PBMC because the monocyte lineage cells within PBMC can express CD 1d molecule and present specific glycolipids like ? Galcer to them.