Purpose: It is obvious that malignant cells evade from immune system in patients with manifest malignancy. Deficient major histocompatibility complex (MHC) class I and costimulatory molecules on malignant cells partially consist of evasion strategy since antigen bond MHC and costimulatory molecules provide two signals necessary for T cell activation. Therefore, enhancement of MHC-I and costimulatory molecules may favor restraint of the evasion. For this purpose, Ganoderma lucidum Polysaccharides (Gl-PS) was used on B16F10 melanoma cells in this study.
Methods: Immunocytochemistry and flowcytometry were used to determine the H-2K(b) and H-2D(b) (two prominent MHC class I molecules in C57BL mouse) as well as B7-1 and B7-2 (two prominent costimulatory molecules) expression on B16F10 cells after incubation with Gl-PS, while messenger ribonucleic acid (mRNA) of these molecules was detected by reverse transcription polymerase chain reaction (RT-PCR).
Results: The H-2K(b) and H-2D(b), and B7-1 and B7-2 on B16F10 cells and mRNAs of these molecules were enhanced by Gl-PS, and more efficient antitumor cytotoxicity was induced by the Gl-PS treated cells.
Conclusions: The MHC class I molecules and costimulatory molecules may be enhanced by Gl-PS, and more efficient immune cell mediated cytotoxicity against these B16F10 cells may be induced, which may favor cancer therapy.