Construction of random tumor transcriptome expression library for creating and selecting novel tumor antigens

Novel tumor antigens are necessary for the development of efficient tumor vaccines for overcoming the immunotolerance and immunosuppression induced by tumors. Here, we developed a novel strategy to create tumor antigens by construction of random tumor transcriptome expression library (RTTEL). The complementary DNA (cDNA) from S180 sarcoma was used as template for arbitrarily amplifying gene fragments with random primers by PCR, then ligated to the C-terminal of HSP65 in a plasmid pET28a-HSP for constructing RTTEL in Escherichia coli. A novel antigen of A5 was selected from RTTEL with the strongest immunotherapeutic effects on S180 sarcoma. Adoptive immunotherapy with anti-A5 sera also inhibited tumor growth, further confirming the key antitumor roles of A5-specific antibodies in mice. A5 contains a sequence similar to protein-L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1). The antisera of A5 were verified to cross-react with PCMT1 by Western blotting assay and vice versa. Both anti-A5 sera and anti-PCMT1 sera could induce antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity toward S180 cells by in vitro assay. Further assay with fluorescent staining showed that PCMT1 is detectable on the surface of S180 cells. Summary, the strategy to construct RTTEL is potential for creating and screening novel tumor antigens to develop efficient tumor vaccines. By RTTEL, we successfully created a protein antigen of A5 with significant immunotherapeutic effects on S180 sarcoma by induction of antibodies targeting for PCMT1.

A study on anti-tumour effect of Solanum lyratum Thunb. extract in S₁₈₀ tumour-bearing mice

The objective of the study was to investigate the anti-tumour effect of ethanol extract of Solanum lyratum Thunb. in S₁₈₀ tumour-bearing mice, and to preliminarily explore its mechanism of action.

METHODS

Mice were made into S₁₈₀ solid tumour model, grouped and administered. Tumour inhibition rate was measured by harvesting the tumours. Serum IL-2, TNF-a contents were measured by taking blood samples, and thymus index and spleen index were measured by harvesting the thymus and spleen. The results showed that the Solanum lyratum Thunb. extract had certain tumour inhibitory effect, which can elevate the serum IL-2, TNF-a contents, and increase the thymus and spleen indices to a certain extent. The study concluded that Solanum lyratum Thunb. extract has certain in vivo anti-tumour effect which may be exerted through enhancing the body immunity.

Study on anti-tumor effect of total glycosides from Radix paeoniae rubra in S180 tumor-bearing mice

The objective of the paper was to study the anti-tumor effect of total glycosides from Radix paeoniae rubra in S180 tumor-bearing mice, and to preliminarily explore its mechanism of action. Mice were made into S180 solid tumor model, grouped and administered with the extracts; tumor inhibition rate was measured by harvesting the tumors, and serum IL-2 and IL-4 levels were measured by taking blood samples. Total glycosides of Radix paeoniae rubra significantly inhibited the growth of tumor cells in tumor-bearing organisms, enhanced the cytotoxic activity of NK cells, and increased the serum IL-2 and IL-4 levels. Total glycosides of Radix paeoniae rubra have some anti-tumor effect in vivo, which might have been accomplished through the regulation of the immune system.