Résumé
Myeloid-derived suppressor cells ( MDSC) are a bone marrow-derived heterogeneous cell population with immuno-suppressive activity.Although there is convincing evidence that autoimmune diseases are associated with MDSC expansion ,controversies remained regarding the role of MDSCs in controlling autoimmune responses .Recent studies have shown that the expansion of MDSCs , which are capable of inhibiting effector cell function in vitro ,does not always lead to alleviation of autoimmune diseases ,and in some ca-ses paradoxically exacerbates the disease progression .This review summarizes recent insights into the role of MDSCs in the development of autoimmune responses and the potential of using MDSCs for the treatment of autoimmune diseases .
Résumé
Objective:To discuss the prokaryotic expression system and purification conditions of Toxoplasma gondii profilin-like protein (TgPRF), and to provide basis for the study on anti-tumor immuno-adjuvant. Methods:The coding region of TgPRF gene was amplified with a pair of specific primers which were designed according to the cDNA of tachyzoites of Toxoplasma gondii RH strain.The PCR products were cloned into the pET-28a (+ ) vector after double enzyme digestion. The recombinant pET28a (+ )-TgPRF plasmid was transformed into E.coli DH5αcells.The positive clones were selected by the double restrictive enzyme digestion and sequencing.The correct pET28a (+)-TgPRF plasmid was transformed into E.coli BL21 (DE3)and induced for 4 h by IPTG.The expression of recombinant TgPRF protein was analyzed by SDS-PAGE method;the expression of recombinant protein His-profilin was detected by Western blotting method.Results:The length of product of PCR was 492 bp.The recombinant plasmid pET28a-TgPRF was confirmed by double restriction enzyme digestion and sequencing.The SDS-PAGE results showed that the target protein was expressed in E.coli BL21 (DE3)in bacteria supernatant.The purified TgPRF protein was obtained by Ni-NTA agarose gel column chromatography with the purity>90%.The Western blotting results revealed that the recombinant TgPRF protein could be recognized by Anti-His antibody.Conclusion: The recombinant plasmid pET28a-TgPRF is successfully constructed,and the TgPRF protein is obtained with the soluble prokaryotic expression.
Résumé
Objective In order to investigate the synaptic plasticity in dentate gyrus after seizures and axonal and dendrtic sprout- ing induced by KA administration. Methods The density of synapses, the curvature forms of synaptic interface were studied under electron microscope. Results 1 .The density of the synapse is decreased obviously 3 days after KA injection, while the density of synapses is increased to control level 7 days after KA injection. 2. Compare with the curvation forms of synaptic interface of control animals and 3days after KA administration animals, the amount of smile synapses is significantly decresed and the amount of frown synapses is significantly increased in the moleculous layer of dentate gyrus 7 days after KA injection. Conclusions 1 .This result demonstrates that the axonal and dendritic sprouting of dentate granule cells is functional. 2. The increase of frown synapse is related to the release of glutamate of sprouting mossy fibers.