C57BL/6 Neuromuscular Healthspan Scoring System

Abstract

PRSS14, also known as epithin and matriptase, has important roles in the various stages during cancer progression, such as angiogenesis, epithelial-mesenchymal transition (EMT), transendothelial migration, and metastasis. Our earlier studies showed that metastasis of 4T1 breast cancer cell can be markedly reduced after vaccination with an antigen derived from PRSS14 in the syngenic TH2 type Balb/c mouse model. In order to study the immunological basis of the metastasis reduction by the vaccine, an additional TH1 type C57BL/6 mouse model was established by using the syngenic breast cancer cell lines; B16-F10 and EO771. To address a question if a cancer self antigen is antigenic to specific antibody response, neo self model antigen EGFP is introduced to B16-F10 cell, and the immunogenicity is tested in the normal mouse and the EGFP specific tolerogenic transgenic lines that express EGFP in the different compartment of thymic epithelium. The growth profile of EGFP expressing B16-F10 cell is slower in normal C57BL/6 mice than in the tolerogenic mice, indicating that cancer self antigen is a target for the antigen specific immune response. Although PRSS14 expressing cancer cell line EO771 does not show apparent faster growth of the primary tumor, it shows faster necrosis, lung metastasis, and lower survival rate when compared with PRSS14 non-expressing tumor B16-F10 cell. For improving the vaccine, the longer peptides that can maintain stable structures, Loop and Linear, are designed. When these peptides were tested for the prevention of cancer metastasis along with Alum adjuvants. Multiple vaccinations with the adjuvant show predominant TH2 type specific antibody response and result in antigen specific prevention of EO771 metastasis to the lung. Immunomodulation of TH responses with various adjuvants are verified during the long-term safety assay. While CFA/IFA induces both TH1 and TH2 type responses, CpG-ODNs induces the dominant TH1 type response. Alum and MF59 induce the dominant TH2 type response, suggesting that the TH2 type antibody response can be safely and efficiently raised in C57BL/6 strain. Therefore, it was concluded that the preventive metastasis vaccine is successfully tested in C57BL/6 and the dominant TH immune response can be modulated to TH2 type by selecting an appropriate adjuvant.