Enhanced MHC class I and costimulatory molecules on B16F10 cells by Ganoderma lucidum polysaccharides.

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.

Promoting effects of Ganoderma lucidum polysaccharides on B16F10 cells to activate lymphocytes.

The immune system in patients with cancer often fails to control tumour growth because of deficient immunogenicity of tumour cells. Ganoderma lucidum polysaccharides (Gl-PS) are believed to have anti-tumour effects by boosting host immune function. Additionally, Gl-PS may have some direct effects on tumour cells in the activation of lymphocytes, thus enhancing the immunogenicity of tumour cells. We tested the effects of Gl-PS in lymphocyte activation by incubating Gl-PS with a tumour cell line deficient in antigen presentation. Our study showed that Gl-PS can promote B16F10 melanoma cells to induce lymphocyte proliferation, CD69 and FasL expression and IFN-γ production, indicating that Gl-PS can improve the nature of B16F10 cells to activate lymphocytes. Furthermore, H-2D(b) [a major histocompatibility (MHC) class I molecule], and B7-1 and B7-2 (two prominent co-stimulatory molecules expressed on B16F10 cells) were enhanced by Gl-PS, suggesting that these molecules may at least partially be involved in the process of Gl-PS on B16F10 cells to activate lymphocytes.

Functional recovery of rat hind-limb allografts.

Few papers have assessed the long-term functional recovery of animal limb allografts. In this study, the functional recovery of rat limb allografts was serially and quantitatively investigated for a period of 1 year. The donor's hind limb was orthotopically transplanted into the recipient. Fifteen recipients with allografts were treated with FK506. Functional recovery of the grafted limb was assessed serially by cutaneous reaction test, walking track analysis, and electrophysiologic evaluation. Sensibility improved to a similar extent in both isografts and allografts, and the recovery rate at 1 year was 68 percent, compared to the normal side. Sciatic function index significantly improved to - 70 points after 1 year. The amplitude recorded from the gastrocnemius muscle significantly improved, and the ratio compared to the normal side was 43 percent. Limb isografts and allografts treated with FK506 showed no significant differences in functional recovery. The data can be used as a reference standard for future investigations.

Prolonged survival of rat hindlimb allografts following short-course FK506 and mycophenolate mofetil combination therapy.

The immunosuppressive effect of combined therapy using FK506 and mycophenolate mofetil (MMF) was studied in rat limb allotransplantation. Dark Agouti rat donor hindlimbs were orthotopically transplanted into Lewis rat recipients. In total, 38 models of transplantation were performed and divided into 8 groups that were treated individually or in combination with FK506 + MMF therapy. Animals were immunosuppressed for 28 days and then observed for up to 140 days. Graft rejection was evaluated both macroscopically and histologically. Survival times for rat limb allotransplants receiving combination FK506 + MMF therapy were significantly longer than with FK506 or MMF monotherapy, and this was achieved without serious side effects. A histopathological study demonstrated a significantly lower level of rejection with FK506 + MMF combination treatment compared to groups receiving FK506 or MMF monotherapy. Combined FK506 + MMF treatment can prolong the survival of rat limb allografts.