Objective:To sutdy the effect of 2 chloroadenosine(2 ClA),which is specifically cytotoxic to macrophages,on MTT assay in activation test and cytotoxicity test of lymphocyte.Methods:Using cell culture technique,mouse splenic lymphocytes and peritoneal macrophages were cultured.Lymphocyte activation and specific cytotoxicity to tumor cells and toxicity of 2 ClA to macrophages were measured by MTT assay in the presence or absence of 2 ClA.Results:2 ClA had a strong cytotoxic effect on macrophages.When the activation test and cytotoxicity test of lymphocyte were measured by MTT assay,the optical density values of 2 ClA group was lower than that of control group,and statistic analysis showed P

Objective:To study the specific antitumor effect of DC modified by Hsp70 tumor peptide complexes in vitro and in vivo.Methods:The tumor antigen peptides were acquired from H22 liver cancer cells and bound Hsp70 in vitro by using biochemical technique;the mouse marrow cells were cultured with induction of rmGM CSF and rmIL 4 by using cell culture technique;mouse spleen lymphocytes was stimulated.The cultured DC cells were harvested and activation of lymphocytes was detected by MTT test and cytotoxicity of stimulated and proliferated lymphocytes to H22 tumor cells and Ehrilich ascites carcinoma cells was tested;The inhibitation to tumor was observed in vivo,after stimulated DCs were injected in mice inoculated by tumor cells.Results:DCs could become mature with the effect of Hsp70 H22 peptide complexes and secret IL 12?TNF ??IL 1? and effectively activate lymphocyte;The activated and proliferated lymphocytes could specifically kill H22 cells but not Ehrilich ascites carcinoma cells in vitro;DCs modified by Hsp70 H22 peptide complexes could become one useful kind of vaccines to inhibit H22 tumor growth in vivo.Conclusion:DCs orignied from marrow cells can be effectively modified by Hsp70 H22 peptide complexes,these modified DCs can specifically activate lymphocytes in vitro and effectively induce antitumor immune response.

Objective: To investigate the effect of the dosageof chemotherapeutic agent on tumor chemotherapy linked with biotherapy and provide experimentalevidence for the dose choice of chemical drugs in the combination of chemotherapy and biotherapy.Methods: The high- and low-dosage of MMC was determined by injection of mice with different dosages of MMC. Mice inoculated with H22 hepatic carcinoma cells were treated with different dosages of MMC followed by three different kinds of biotherapy: transfection with plasmid pCH510 in vivo, immunization with Hsp70-tumor antigen peptide complexes and the combination of these two elements. Results: By toxicity test of MMC to mice, it was determined that 100 ?g of MMC was high dosage and 50 ?g was low dosage. The curative effect was significantly improved if chemotherapy was followed by different elements of biotherapy. Better efficacy was obtained when biotherapy elements were used to follow the chemotherapy with high dosage of MMC. In the case of low dosage of MMC, no difference could be observed in curative effect of three different kinds of biotherapy. When high dosage of MMC was used, the curative effect of three different kinds of biotherapy was signiferently different. The best efficacy was obtained if chemotherapy was followed by the combination of two biotherapy elements, transfection with plasmid pCH510 in vivo and immunization with Hsp70-tumor antigen peptide complexes. Conclusions: Using different chemical dosages, the curative effect of chemotherapy linked with biotherapy is different. In the case of high dose, the chemotherapy linking with biotherapy can reach more better efficacy.

Objective: To invistigate the relationship between time and efficacy of the linkage of tumor biotherapy after chemotherapy by studying the influence of chemotherapeutic drugs on immunocytes.Methods: The cytotoxicity of chemotherapeutic drugs to tumor cells, mouse peritoneal macrophages and spleen lymphocytes was observed by cell culture technique. The influence of chemotherapeutic drugs to the metabolism and activation of macrophages and lymphocytes at different time after peritoneal injection of drugs was observed. The mice were inoculated with tumor cells two days after the injection of drugs, and the growth of tumor was measured 14 days after inoculation by anatomizing mice. Results: Chemotherapeutic drugs had cytotoxicity in vitro to different cells, suppressed the function of immunocytes, and decreased the number of immunocytes in vivo. After injection of drugs, the number of immunocytes was the lowest on the third day and recovered to the nomal level on the 10th day. If drugs was injected two days before the inoculation of tumor cells, the growth of tumor became faster than control group. Conclusions: Chemotherapy not only decreases the number of immunocytes but also suppresses the function of immunocytes, and it can promote the growth of tumor after its cytotoxicity disappeared. So it is not good that biotherapy, which depends on immunocyte to kill tumor cells, is used immediately after chemotherapy and it is also not good for using biotherapy with a long interval after chemotherapy . It is good time to use biotherapy when the number of immunocytes is lowest or the recovery just starts.

Objective:To investigate the effect of eucaryotic expression plasmid DNA on activation of macrophage and the mechanism Methods:NO production by macrophages,the expression of surface molecules on macrophage by FACS and the cytotoxicity of macrophage were measured by Griess method,FACS and MTT respectively Results:The results showed that macrophages were activated to produce NO by plasmid pCH510 and pcDNA3 1 respectively in vitro or in vivo The expression of MHC Ⅱand B7 1 on macrophage and the cytotoxicity of macrophage was increased Plasmids DNA in combination with IFN ? but not with CH50 augmented the activation of macrophage in vitro In contrast, the activation of the macrophage were enhanced when the stimulated macrophages by plasmid DNA in vivo were treated by addition of CH50, but not IFN ? Conclusion:The results suggested the plasmid DNA could activate macrophage in vitro or in vivo but the mechanism of activation was different In vitro, the plasmid DNA directly activated macrophage and had synergistic effect with IFN ?,while in vivo macrophages were mainly indirectly activated and the activation of macrophages was enhanced in the presence of CH50 When eucaryotic expression plasmid pCH510 was used in gene therapy of tumor, besides the function of its products expressed, the plasmids showed the significant role in tumortherapy by its direct immune activation of macrophages

Objective: To study the main features of CH50, a recombinant polypeptide of human fibronectin, to activate macrophages in vivo and its anti-tumor function. Methods: CH50 was injected and IFN-? gene was transfected in mice several kinds of factors produced by marcrophages were determined. The growth of tumor in force was also measured. Results: CH50 could enhance the production of such factors as NO, TNF and IL-1 by macrophages, but the activation of macrophages was rela- tively slow when CH50 was used in vivo alone. CH50 and IFN-? could synergistically activate macrophages rapidly in vivo no matter whether the injection of CH50 or the transfection of IFN-? gene was Performed first.Injection of CH50 alone inhibited the formation of tumor nodes in a dose-dependent manner. There was strong inhibition of low dosage of CH50 on the formation of tu- mor nodes smaller than 1 mm, and high dosage of CH50 on those bigger than 1 mm. A stronger inhibition on the growth of tumor in vivo was obtained by the synergistic effect of CH50 and IFN-?. Conclusion: CH50 and IFN-?, as double-signal factors for activation of macrophages, will be potentially useful in tumor therapy.

Objective: To explore the preventive and therapeutic effects of Hsp70-antigen peptide complexes (HACs) on pulmonary metastasis of malanoma B16 cells in mice. Methods: Antigen peptide mixtures were prepared from massive tumors and metastatic foci respctively, and bound with Hsp70 in vitro. The HACs were used to mice to prevent the formation of micrometastatic foci after the injection of B16 cells through tail vein, or treat the existent micrometastatic foci in lung The number of metastatic foci was counted and the cytotoxicity of splenocytes to B16 cells was determined. Results: After immunization with HACs, the number of metastatic foci in mice decreased significantly (P

OBJECTIVETo prepare tumor antigen peptides from HL-60 cells and to induce specific immune response.

METHODSHL-60 antigen peptides were obtained using techniques including freezing and thawing, heat precipitation and acid precipitation. The stimulating effect of the in vitro Hsp70 binding HL-60 peptides on PBMC and the proliferation of stimulated PBMC were observed by T cell activation test. The cytotoxicity of proliferated PBMC is detected by incubating HL-60 cells or K562 cells with PBMC respectively.

RESULTSThe obtained tumor antigen peptides were a peptides mixture. The mixed peptides could activate PBMC and cause PBMC proliferation in vitro after presented by Hsp70. The proliferated PBMC showed specific cytotoxicity to HL-60 cells but not to K562 cells.

CONCLUSIONThe method for preparing of human leukemia tumor antigen peptides used in this paper is simple and easy; the obtained antigen peptides can induce specific immune response in vitro.

Cell Division ; HL-60 Cells ; HSP70 Heat-Shock Proteins ; immunology ; Humans ; K562 Cells ; Killer Cells, Natural ; immunology ; Leukocytes, Mononuclear ; cytology ; immunology ; Neoplasm Proteins ; immunology ; Peptides ; immunology

To construct an eukaryotic expressing vector that expresses CH50, a recombinant CellⅠ-HepⅡ bifunctional-domain polypeptide of human fibronectin, and to investigate the chemotaxis to immune cells and the inhibitory effect on the growth of tumor by the expression of the plasmid in vivo, the plasmid was constructed by DNA recombination. Gene transfection was performed in vitro and in vivo. The expressed product was identified by Western blot. The chemotaxis after gene transfection in vivo was observed by histotomy and staining of muscle tissues. The inhibition of gene transfection on solid tumor was observed in mice. The results showed that plasmid pCH510 was constructed by the recombination of the 5′-terminal noncoding region and signal peptide coding region of human fibronectin cDNA and cDNA fragment coding CH50 polypeptide with a 3′-terminal noncoding region of human FN cDNA, and the insertion of the recombinated fragment into plasmid pcDNA3.1. After transfection with plasmid pCH510, NIH3T3 cells could produce CH50 polypeptide. The transfection of plasmid pCH510 by the injection in muscle of mouse could produce the effects of chemotaxis on immune cells and the inhibition on the growth of solid tumor. It is concluded that plasmid pCH510 can express in cells and in vivo in mouse. The expression of the plasmid in vivo has a chemotactic effect on immune cells and can inhibit the growth of solid tumor.

To construct an eukaryotic expressing vector that expresses CH50, a recombinant CellⅠ-HepⅡ bifunctional-domain polypeptide of human fibronectin, and to investigate the chemotaxis to immune cells and the inhibitory effect on the growth of tumor by the expression of the plasmid in vivo, the plasmid was constructed by DNA recombination. Gene transfection was performed in vitro and in vivo. The expressed product was identified by Western blot. The chemotaxis after gene transfection in vivo was observed by histotomy and staining of muscle tissues. The inhibition of gene transfection on solid tumor was observed in mice. The results showed that plasmid pCH510 was constructed by the recombination of the 5′-terminal noncoding region and signal peptide coding region of human fibronectin cDNA and cDNA fragment coding CH50 polypeptide with a 3′-terminal noncoding region of human FN cDNA, and the insertion of the recombinated fragment into plasmid pcDNA3.1. After transfection with plasmid pCH510, NIH3T3 cells could produce CH50 polypeptide. The transfection of plasmid pCH510 by the injection in muscle of mouse could produce the effects of chemotaxis on immune cells and the inhibition on the growth of solid tumor. It is concluded that plasmid pCH510 can express in cells and in vivo in mouse. The expression of the plasmid in vivo has a chemotactic effect on immune cells and can inhibit the growth of solid tumor.