Objective To explore the roles of PKCθ(protein kinase Cθ)signaling pathway on the activation,proliferation and TH1/TH2 cytokines production of the γδT lymphocytes stimulated by Mycobacterium tuberculosis antigen(Mtb-Ag) in vitro.Methods Peripheral blood mononuclear cells(PBMC)were pretreated with or without Rottlerin at 5.0 μmol/L,and stimulated with Mtb-Ag and cultured in rhIL-2 containing medium.After different time of culture,activation molecules and cytokines production of γδT cells were measured by flow cytometry.The proliferation proportion and the percentage of each generation of γδT cells were determined by carboxylfluoreseein diacetate succinmidyl ester(CFSE)labeling technique and flow cytometry.Results After 3d of stimulation with Mtb-Ag,the expression rates of CD69 and CD25 of γδT cells were 46.2%and 45.6%,respectively.Pretreatment of 5.0 μmol/L Rottlerin markedly inhibited the both expressions of CD69 and CD25 in γδT cells(P＜0.01).After stimulation and expansion in vitro for 5,10,and 15 d,the percentages of the γδT cell were 9.6%,54.6%and 82.4%,respectively.There was a few γδT cells in propagation on the 5th day of culture,and almost all γδT cell divisions were above 6 generations on the 10th and 15th day of culture.Pretreatment of the Rotflerin significantly suppressed the γδT cell proliferation,but after 10 d culture,there were still a few parts of γδT cells in propagation.Meanwhile,after 7,14,and 21d of culture,upon stimulation with PMA+Ionomycin,the IFN-γ producing-γδT cells were about 80%at all times.But only after 21d culture,IL-4-producing γδT cells was 2.6%.,The percentage of IFN-γ producing γδT cells markedly reduced in Rottlerin group(P＜0.01).IL-4 secretion of the γδT cells was almost completely blocked.Conclusion PKCO signal pathway involves in activation,proliferation and differentiation of the γδT lymphocytes stimulated by Mtb-Ag.

Objective This study is aimed at determining whether anti-von Willebrand factor (VWF) autoantibodies are present in the plasma of idiopathic thrombotic thrombocytopenic purpura (TTP) patients with normal ADAMTS13 activity and undetectable anti-ADAMTS13 antibodies,and at examining whether murine monoclonal antibodies (mAbs) against human VWF decrease the susceptibility of VWF to ADAMTS13 in vitro.Methods Anti-VWF autoantibodies and ultralarge VWF (UL-VWF) multimers were measured in plasma samples of 53 adult patients with idiopathic TTP by enzyme-linked immunosorbent assay and sodium dodecylsulphate-agarose gel electrophoresis,respectively.Moreover,the effects of eight murine mAbs to different human VWF domains on VWF cleavage by ADAMTS13 were evaluated under fluid shear stress and static/denaturing conditions,respectively.Results Anti-VWF antibodies and UL-VWF multimers were detected in two TTP patients with normal ADAMTS13 activity and undetectable anti-ADAMTS13antibodies.The SZ34,an anti-VWF mAb,inhibited VWF proteolysis mediated by ADAMTS13 under flow,but not static conditions.Conclusion Anti-VWF antibody may be one of the causes of idiopathic TTP with normal ADAMTS13 activity and undetectable anti-ADAMTS13 antibodies.

This study was to acquire recombinant protein of von Willebrand factor cleaving protease (ADAMTS13, a disintegrin and metalloprotease with a thromboSpondin type 1 motifs 13), for further studies on its biological function in thrombosis and hemostasis. We transfected the Hela cells with the plasmid pSecTag-ADAMTS13 by lipofectamine. A positive cell cloning was selected by hygromycin-B. The recombinant protein was purified with Ni-NTA agarose column by gradient imidazole. The purity and immune activity of purified products were identified with SDS-PAGE and Western blotting respectively. We also measured the enzymatic activity of recombinant protein (rADAMTS13) by GST-His two-site ELISA assay. The results showed that we successfully constructed Hela cells ADAMTS2-4 which expressed high level of rADAMTS13. We received about 5.8 mg recombinant protein in culture supernantants per liter purified with Ni-NTA column. The protein formed a main lane at the position of 190 kDa with SDS-PAGE and reacted with polyclonal antibody against ADAMTS13 by Western blotting. The amount of rADAMTS13 activity was 6.4 U/mL, according to the normal plasma defined as 1 U/mL. In conclusion, rADAMTS13 protein had high purity, immune activity and good enzymatic activity, which could establish the experimental foundation for further research on biological function and mechanism of this unique metalloprotease.
ADAM Proteins ; biosynthesis ; genetics ; metabolism ; ADAMTS13 Protein ; HeLa Cells ; Humans ; Recombinant Proteins ; biosynthesis ; genetics ; metabolism ; Transfection ; von Willebrand Factor ; metabolism