title: [Experimental study of adoptive immunotherapy using CD3AK cells].
abstract: OBJECTIVE
  To analyze the immunological properties and biological activity of a monoclonal antibody (mAb) against CD3 molecule(yCD3), and to observe the tumor-suppressive activity of CD3AK cells in vitro and in vivo.
  
  
  METHODS
  FCM was used to test the specificity of yCD3 and the immunological phenotype and cytokine production of CD3AK. 3H-TdR assay was used to measure the transformation of lymphocytes activated by yCD3. LDH assay was used to analyze the cytotoxic activity of CD3AK in vitro. Mice bearing tumors were used to observe the anti-tumor effect of CD3AK cells.
  
  
  RESULTS
  yCD3 could bind specifically to T cells. 5 microg yCD3 could competitively inhibit 70% of standard anti-CD3 antibody to bind with CD3 molecules on cell membrane. 8 microg/L of yCD3 stimulated the proliferation of peripheral blood lymphocytes, which could be further boosted by IL-2 or anti-CD28 antibodies. Among activated CD3AK cells, CD3+, CD8+, and CD25+ cells increased. IL-2 and IFN-gamma producing CD3+ cells were also increased, to 3.29- and 2.47- fold, respectively, under the co-stimulation of anti-CD28 antibody. When the ratio of effective cells and target cells was 80:1, 57.54% target cells were killed. As compared with control, the percent of tumor inhibition in CD3AK cells treated tumor-bearing mice was 33.17%, and the inhibition rate of lung metastasis was 39.70%. The CD3AK cells treatment was more effective when combined with LAK cells.
  
  
  CONCLUSIONS
  yCD3 could activate T cells and significantly induce the tumor-suppressive activity of CD3AK cells in vitro and in vivo, which lays a foundation for adoptive immunotherapy against tumors in clinical medicine.
authors.affiliation: Institute of Basic Medicine, Academy of Military Medical Sciences, Beijing 100850, China. sunyx@amms.ac.cn
authors.forename: Ying-xun
authors.initials: YX
authors.lastname: Sun
authors.forename: Shao-hui
authors.initials: SH
authors.lastname: Cheng
authors.forename: Ming
authors.initials: M
authors.lastname: Yu
authors.forename: Yong-huai
authors.initials: YH
authors.lastname: He
authors.forename: Chun-ning
authors.initials: CN
authors.lastname: Lai
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Bei-fen
authors.initials: BF
authors.lastname: Shen
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D017252:CD3 Complex / Q000276:immunology*; D002471:Cell Transformation, Neoplastic / Q000276:immunology; D016207:Cytokines / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology; D006801:Humans; D016219:Immunotherapy, Adoptive / Q000379:methods*; D007694:Killer Cells, Natural / Q000276:immunology*; D008175:Lung Neoplasms / Q000276:immunology / Q000556:secondary / Q000628:therapy; D051379:Mice
chemical_list: D000911:Antibodies, Monoclonal; D017252:CD3 Complex; D016207:Cytokines