Candida albicans Structural and Secreted Proteins Modulate CD4/CD8 Ratio in Tumor Infiltrating Lymphocytes of Spontaneous Adenocarcinoma Bearing Mice

Background: Candida albicans is one of the most important opportunistic pathogens that suppress immunologic mechanisms of the host. It is speculated that structural and secretory proteins of C. albicans have immunomodulatory effects in cancer. Objective: To evaluate the effects of C. albicans structural and secreted proteins on intratumoral CD4/CD8 ratio as well as the survival rate in BALB/c tumor model. Methods: Structural and secretory proteins from C. albicans were isolated and examined for their effects on tumor growth and survival of adenocarcinoma bearing mice. Results: The results indicated that in mice treated with C. albicans structural protein, the survival rate significantly decreased compared with the control groups. Also, mice treated with secretory proteins showed a decrease in survival rate but it was not statistically significant (p>0.05). Investigating the frequency of tumor infiltrated CD4+ and CD8+ T lymphocytes indicated that the percentages of tumor infiltrated CD4+ T lymphocytes in response to structural and secreted proteins were higher compared to the control groups. Conclusion: Our study suggests that C. albicans structural and secreted proteins modulate intratumor T lymphocyte infiltration.