ABSTRACT
Objective To eukaryotically exp ress B7.1 extracellular domian and investigate its biological activities. Methods Recombinant expression vector pDisplay/B7.1(V+C) wa s transfected into Hela cells by electroporation method. The expression of B7.1( V+C) was identified by immunohistochemistry and in situ hybridization, respectiv ely. In vitro T lymphocyte activation activity was detected by 3H-TdR incoporation method and the aroused cytotoxicity after mixed culture of pDispla y/B7.1(V+C) transfected Hela cell-T cell was observed by MTT method. R esults B7.1(V+C) was expressed successfully on the surface of Hela c ells. The expressed B7.1(V+C) was able to activate T lymphocytes in the pres ence of anti-CD3 monoclonal antibody. Cytotoxicity could be observed when pDisp lay/B7.1(V+C) transfected Hela cells were mixed and co-cultured with T lymphocy tes. Conclusion Eukaryotically expressed B7.1(V+C) main tains its T lymphocyte costimulatory activity, and B7.1(V+C) can be adopted to construct bifunctional molecules for tumor immunotherapy.
ABSTRACT
Objective To establish a human cervical carcinoma cell line. Methods A primary culture was initiated from malignant tissue collected by dissection of cervical biopsy specimens.Characterizing cells in culture which included morphological observation,biological and karyotypic analysis,experimental tumorigenesis and the expression of p53,bcl-2 and Ki67 genes was carried out. Results The new established cervical carcinoma cell line (CS1213) had been maintained in culture for over 170 generations.The cells which were nonadherent had a common,rounded appearance with a cell cycle time of 25-hour and a 19 colony formation rate in soft agar.Electron micrographs demonstrated abundant tonofilaments in the cytoplasm.The karyotype showed a hyperdiploid feature with a main chromosome stem number ranged from 80 to 88.The culture was not contaminated by mycoplasma and had a distinct lactic acid dehydrogenase isozyme pattern.High expression level of p53(31.9%),bcl-2(89.3%) and Ki67(33.7%) proteins was detected by flow cytometry.The xenogeneic tumors were grown in nude mice with the histological structure of the original one. Conclusions The novel CS1213 cells have the characteristics of human cervical squamous cells and could be used as an appropriate cellular model system for studying tumor invasion and metastasis.
ABSTRACT
For over twenty years, the Insitute of Immunopathology of Xi'an Medical University, the antecedent Institute of Cancer Research, has long been engaged in the study on tumor immunity. Beginning with the exploration of the mechanisims for the activation of tumor-infiltrating lymphocytes(TIL) and tumor evasion till translating the relevant achievements into tumor immunotherapy and immunoprevention. From one facet, all the facts reflect the arduous course of the struggle of human beings for conquering cancer.