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CAR-T cell therapy that targets surface antigens to kill tumor cells specifically has recently become another cornerstone in tumor immunotherapy. In this study, a lentiviral expression plasmid of CAR targeting human epidermal growth factor receptor 2 (HER2) was constructed by genetic engineering. The recombinant plasmid was co-transfected with other packaging plasmids into HEK293T cells by calcium phosphate precipitation to generate lenti-car, which are CAR lentiviral particles. HER2-specific CAR-T cells were obtained by transducing human peripheral blood mononuclear cells with lenti-car. Their specific inhibitory effects on HER2-positive and HER2-negative tumor cells were analyzed in vitro. The constructed CAR-T cells were specifically activated by HER2-expressing tumor cells as indicated by secretion of IFN-γ and IL-2. The inhibitory rate on HER2-positive SK-OV-3 cell line was (58.47±1.72)%, significantly higher than that on the mock-treated control group (P<0.05). The inhibitory rate on HER2-negative K562 cell lines was (11.74±2.37)%, which was not significantly different from that on the control group (P>0.05). Furthermore, when we transfected a HER2-expressing vector into K562, the inhibitory rate increased to (30.41±7.59)%, which was higher than that on HER2-negative K562 (P<0.05). Thus, the constructed second-generation HER2-specific CAR-T cells specifically suppressed growth of tumor cells overexpressing HER2 protein, suggesting that HER2-specific CAR-T cells might prove useful for immunotherapy of HER2-positive cancer.
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Objective To investigate the possibility of tumor abnormal protein ( TAP) ,as index of diag-nosis and prediction of prognosis in gastrointestinal tumors (GITs).Methods The outpatients and inpatients as well as healthy physical examinees in our hospital were chosen as objects in the present study .The patients were divided into GIT group(120 cases),high-risk GIT group(123 cases)and normal group(117 cases).TAP ex-pression was detected in three groups.These study objects were followed up for one and a half years .Then the re-lationship between TAP expression and the occurrence or recurrence of tumors was analyzed .Rseults There were significant differences(P<0.001)among the three groups on the positive TAP with critical expression rate .TAP detections to GITs diagnosis sensitivity ,specificity ,positive predictive value ,negative predictive value and Youden index were 88.33%,85.83%,75.71%,93.64% and 0.74 respectively.TAP positive non GITs crowd tumori-genesis proportion (23.53%)was significantly higher than that of TAP -negative(0.49%)(P<0.001).GITs TAP positive patients relapse rate(33.33%)was significantly higher than negative ones (6.90%)(P<0.001). Conlcusion TAP can be an index for diagnosis ,early prevention ,monitoring of treatment effect and prediction of prognosis of gastrointestinal tumor .
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Influenza pandemic poses public health threats annually for lacking vaccine which provides cross-protection against novel and emerging influenza viruses. Combining conserved antigens inducing cross-protective antibody response with epitopes activating cross-protective cytotoxic T-cells would offer an attractive strategy for developing universal vaccine. In this study, we constructed a recombinant protein NMHC consisting of influenza viral conserved epitopes and superantigen fragment. NMHC promoted the mature of bone marrow-derived dendritic cells and induced CD4+ T cells to differentiate into Th1, Th2 and Th17 subtypes. Mice vaccinated with NMHC produced high level of immunoglobulins which cross-bound to HA fragments from six influenza virus subtypes with high antibody titers. Anti-NMHC serum showed potent hemagglutinin inhibition effects to highly divergent group 1 (H1 subtypes) and group 2 (H3 subtype) influenza virus strains. And purified anti-NMHC antibodies could bind to multiple HAs with high affinities. NMHC vaccination effectively protected the mice from infection and lung damage challenged by two subtypes of H1N1 influenza virus. Moreover, NMHC vaccination elicited CD4+ and CD8+ T-cell responses to clear the virus from infected tissue and prevent virus spreading. In conclusion, this study provided proof of concept for triggering both B cells and T cells immune responses against multiple influenza virus infection, and NMHC may be a potential candidate of universal broad-spectrum vaccine for various influenza virus prevention and therapy.