Therapeutic effects of simultaneous expression of 4-1BBL and sPD-1 on experimental murine hepatoma / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the possible negative regulatory elements induced by the treatment of experimental murine hepatoma with 4-1BBL, and to investigate the synergistic effects and mechanisms of 4-1BBL and soluble PD-1 (sPD-1) in tumor therapy.</p><p><b>METHODS</b>Mice were inoculated intramuscularly (i.m.) with 5 x 10(5) H22 tumor cells in the right hind thigh to establish the experimental hepatoma model. The mice were randomly divided into 5 groups (12 mice in each group) after inoculation. The mice of group A, B, C and D were injected with NS, plasmid pcDNA3.1, plasmid p4-1BBL and plasmid pPD-1A respectively. The mice in group E, the combinatorial treatment group, were injected with plasmid p4-1BBL and pPD-1A together. Then the anti-tumor effects, using the tumor growth rates and mice survival rates and others as parameters, were recorded. Meanwhile, the phenotype of lymphocytes and residual tumor cells in the peri-tumor tissue were analyzed.</p><p><b>RESULTS</b>Either transfection with 4-1BBL gene alone or with sPD-1 alone could inhibit tumor growth to some extent, but a more significant anticancer effect was obtained in the combinatorial treatment group (group E), in which the tumors were completely inhibited in 42% of the mice, compared with 0 in the other groups. In addition, the survival rate of mice in group E was 100%, compared with 30% in group B, 65% in group C and 62% in group D. The FACS analysis results showed that the expression level of B7-H1 and B7-DC on residual tumor cells in group C (injected with p4-1BBL alone) was higher than that on cells in other groups. The amount of CD8+ T cells in the peri-tumor tissue of group E was significantly increased.</p><p><b>CONCLUSION</b>4-1BBl can induce an up-regulation of negative regulatory elements and at the same time it can enhance the anti-tumor response. The combinatorial treatment with 4-1BBL and sPD-1 can produce a positive synergistic anti-tumor effect on our murine experimental hepatoma.</p>

The inhibitory effect of recombinant polypeptide CH50 of fibronectin on invasion and angiogenesis of tumors / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the inhibitory effect of recombinant polypeptide CH50 of fibronectin on invasion and angiogenesis of tumors, and analyze the possible molecular mechanism of the therapeutic effect of polypeptide CH50 on tumors.</p><p><b>METHODS</b>The tumor model was established by inoculation of H22 hepatocarcinoma cells in mice. The tumor gene therapy was performed by in vivo gene transfection with a method based on hydrodynamics to express polypeptide CH50. After treatment, the inhibitory effect on tumor invasion and angiogenesis was observed by histotology with HE staining of tumor tissues. The expresison of MMP-9 mRNA and protein at the edge of tumor tissue was evaluated by RT-PCR and gelatin zymography, respectively. RT-PCR was used to detect the expression of the related genes in H22 cells treated with polypeptide CH50. Cell adhesion assay was used to analyze the influence of polypeptide CH50 on the binding of cells to fibrinogen.</p><p><b>RESULTS</b>(1) Eukaryotic expression plasmid pCH510 was expressed in vivo in a non-targeting manner and produced a significant inhibitory effect on tumor growth. The therapy with polypeptide CH50 resulted in pronounced necrosis of tumor cells in pCH510 group, compared with that in control groups at histological level. (2) Polypeptide CH50 could inhibit the growth, invasion and angiogenesis of the tumor, and interfere the formation of new collateral circulation in the tumor. (3) The expression level of MMP-9 protein at the edge of tumor tissue was significantly decreased after treatment, especially the activation of pro-MMP-9 was inhibited significantly, whereas the expression level of MMP-9 mRNA was not influenced. (4) The expression of alphav, 33 and cdc2 mRNAs in H22 cells treated with polypeptide CH50 was down-regulated. (5) Cell adhesion assay manifested that polypeptide CH50 can affect the adhesion ability of H22 cells.</p><p><b>CONCLUSION</b>Polypeptide CH50 can inhibit tumor growth and angiogenesis by suppressing the functions of MMP-9 and integrin alphavbeta3.</p>

Eukaryotic expression and functional characterization of PD-1 extracellular domain / 生物工程学报

The negative signal provided by interactions of costimulatory molecules, programmed death-1 (PD-1) and its ligands, PD-L1 (also B7-H1) and PD-L2 (also B7-DC), is involved in the mechanisms of tumor immune evasion. To block PD-Ls-PD-1 interactions by a soluble receptor of PD-1, we constructed a eukaryotic expression plasmid that expresses extracellular region (aa1-aa167) of murine PD-1 (pPD-1A) and, another version of pPD-1A, pPD-1B, carrying cDNAs encoding for both extracellular region of PD-1 and green fluorescent protein (GFP) reporter gene, which was inserted downstream of PD-1. Experiment of BHK cells transfected with pPD-1B determined that most expression product (sPD-1) in the cells was secreted out. FACS analysis revealed that sPD-1 was specific and bound efficiently to PD-1 ligands. Cytotoxicity assay showed that blocking PD-Ls on either tumor cells or spleen cells by sPD-1 mediated enhanced lysis of H22 cells by Hsp70-H22 peptides complexstimulated spleen cells. The constructed plasmid vector would provide a novel method of tumor gene therapy of blocking PD-Ls-PD-1 interactions by expression of soluble receptor of PD-1 in tumor sites, which could increase the antitumor activity.

Therapeutic effect of secretive endostatin eukaryotic expressing plasmid on mouse hepatoma / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To construct and express secretive endostatin eukaryotic plasmid for treatment of hepatoma.</p><p><b>METHODS</b>Mouse Igk signal peptide sequence was synthesized and cloned into pcDNA3.1 with endostatin gene. The supernant of BHK-21 transfected with recombinant was used to culture ECV304. The proliferation of latter was evaluated by MTT assay. H22 was inoculated intramusclely, then naked DNA of endostatin plasmid was injected into the inoculation site. Tumors were dissected and weighted after treatments. All data was analyzed by SPSS10.0.</p><p><b>RESULTS</b>The supernant of BHK-21 transfected with recombinant can inhibit the proliferation of ECV304 by 29.2%. Tumor weight lighter after injected with naked pSecES (1.34 g+/-0.96g) compared with naked pcDNA3.1 (2.70g+/-0.82g) and saline (3.73g+/-1.41g).</p><p><b>CONCLUSION</b>The endostatin eukaryotic plasmid was constructed and it can be used for gene therapy on hepatoma.</p>

Inhibitory effect on pulmonary metastasis of melanoma in mice by soluble PD-1 and its combina-tion with HspT0-B16 antigen peptides / 中华皮肤科杂志

Objective To investigate the blockade effects of soluble PD-1 (sPD-1) expressed in vivo on B7-H1/PD-1 signal transduction,and inhibitory effect in pulmonary metastasis of melanoma with combi- nation of Hsp70-B16 antigen peptides in mice.Methods The pulmonary metastasis model of melanoma was established in mice.Immunohistochemical staining and flow cytometry were utilized to detect the expres- sion of PD-1 and B7-H1 respectively in pulmonary metastasis loci.Four days after the inoculation of tumor cells,forty murine models of pulmonary metastasis were randomly divided to be immunized with normal sodium (group A),empty vector pcDNA3.1 (group B),PDlA plasmid (group C) respectively via tail vein injection,subcutaneous injection of Hsp70-B16 antigen peptides (group D) or with the combination of intra- venous PDlA plasmid and subcutaneous Hsp70-B 16 antigen peptides (group E).The local infiltration with lymphocytes in pulmonary metastasis loci was observed and a series of immunological parameters were assessed 17 days after the inoculation of tumor cells.Results The melanoma pulmonary metastasis model was successfully established.There were a lot of PD-1 positive cells in these loci,and B7-H1 molecule was massively expressed on the surface of B16 cells in metastasis loci.The pulmonary metastasis was inhibited in the mice of group E,and the inhibition rate was 95%,higher than that in other groups (53%,76%,9% in group C,D,B,respectively).The quantity of CD8~+ T cells in pulmonary metastasis loci,cytotoxicity of spleen lymphocytes to tumor cells,and serum concentration of IL-2 and IFN-?were all significantly elevated in the mice of group E as compared with those of other groups (all P

Specific anti-tumor immunity and its cross-reaction induced by antigen peptide mixture prepared from different T lymphocytic leukaemia cell lines / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the specific antitumor immunity induced by antigen peptide mixture prepared from different T lymphocytic leukaemia cells and the cross-reaction among the mixtures of different cell lines.</p><p><b>METHODS</b>Antigen peptide mixtures were prepared from different leukaemia cell lines and then bound with Hsp70 in vitro. The activation and proliferation of peripheral blood mononuclear cell (PBMC) were observed after the stimulation by different Hsp70-peptide complexes. The cytotoxicity of such activated PBMCs to different target cells was assayed.</p><p><b>RESULTS</b>The antigen peptides from different leukaemia cell lines were mixed ones, which could activate PBMC effectively with Hsp70 and stimulate the activated PBMC to proliferate. The proliferative PBMC had specific cytotoxicity to the corresponding leukaemia cells. To Hut-78 cell, Molt-4 cell and Jurkat cell, the cytotoxicity of PBMC activated by either Hut78-peptides or Molt-4-peptides was significantly stronger than that of PBMC activated by HL-60-peptides (P < 0.05). The cytotoxicity to Jurkat cell of PBMC activated by Hut78/Molt-4-peptides was significantly stronger than that of PBMC activated by Hut78-peptides or Molt-4-peptides alone (P < 0.05).</p><p><b>CONCLUSION</b>Antigen peptide mixture from T lymphocytic leukaemia cells is able to induce specific antitumor immunity. There is a cross-reactivity among antigen peptide mixtures from different T lymphocytic leukaemia cell lines, with the more crossed antigen peptides obtained from the mixtures of different antigen peptides from different T lymphocytic leukaemia cell lines, which suggests that the antigen peptide mixture with broad antigenic spectrum could possibly be prepared by using multiple leukaemia cell lines.</p>

Recombinant fibronectin polypeptide CH50 improves positive immune regulation in tumor microenvironment / 中国肿瘤生物治疗杂志

Objective:To investigate the inhibitory effect of in vivo non-targeting transfection of recombinant fibronectin polypeptide CH50 against tumors and to study the related mechanisms.Methods:After inoculated with tumor cells, BALB/c mice were injected with CH50 plasmids,control plasmids,and normal saline separately.The growth of the tumor was observed;the expression of genes (such as B7-1,B7-H1 etc.) in tumor tissues was detected by RT-PCR;and the count of T lymphocytes in local tumor tissues was analyzed by flow cytometry.Results:The tumor growth was obviously suppressed by in vivo CH50 expression.The expression of genes (B7-1 and B7-H1) was up-regulated along with the growth of tumor.CH50 increased the ratios of B7-1/B7-H1 and B7-1/B7-DC and suppressed the up-regulation of IL-10 and TGF-?genes.The direct action of CH50 on H22 cells resulted in the down-regulatoin of TGF-?gene.The count of T lymphoeytes in tumor tissues of CH50 treatment group was significantly higher than that in other groups.Conclusion:Ex- pression of CH50 by non-targeting transfection can effectively inhibit the growth of tumor;the regulation of the immuno- regulatory genes in tumor mieroenvironment is an important part of the treatment mechanism of CH50.

The Experimental Studies On the Promoting Effect of Ligustrum Lucidum and Acanthopanax Senticosus on T Cell / 中国免疫学杂志

The effedt of ligustrum lucidum(LL)and acanthopanax senticosus(AS)on T cells was observed by Ea rosette formation and lymphocyte stimulation test with diff- erent experimental conditions.Both of the two drugs can promote the response of lymphocyte to PHA,but can not stimulate al one lymphocytes to proliferate.LL can raise EaRFC% of lymphocyte and accelerate the restoration of the EaRFC% of trypsin-treated lymphocytes,but AS not.AS can antagonize the inhibition of hydr- ocortisone,but LL not,In this paper,the mechanisms of the action of the two drugs were discussed.