ABSTRACT
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. 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. Structural and secretory proteins from C. albicans were isolated and examined for their effects on tumor growth and survival of adenocarcinoma bearing mice. 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. Our study suggests that C. albicans structural and secreted proteins modulate intratumor T lymphocyte infiltration
ABSTRACT
The aim of the present study was to investigate the effect of protein and DNA components of Toxoplasma gondii on maturation of dendritic cells and their efficiency in IL-12 production and proliferation of T cells. for DC generation, Bone marrow cells were cultured in the presence of GM- CSF and IL-4 for 5 days. Tumor lysate and protein or DNA components of Toxoplasma gondii were added to the culture media and incubated for another 2 days. LPS was added as control for DC maturation. Proliferation of T cells were determined by MLR and IL-1 production was measured by ELISA kit. Maturation of dendritic cell were determined by flowcytometry. DCs treatment with protein components of Toxoplasma gondii caused a significant increase in IL- 1 2 production and proliferation of T cells [P<0.001]. Different compositions of microbial body like protein and DNA components of Toxoplasma gondii can cause augmentation of antigen presentation capacity of DC and their IL-12 production capability. Among these components the protein was more effective as compared to DNA
ABSTRACT
Using a cancer murine model of invasive aspergillosis [IA], we investigated the expression of TLR-2, Dectin-1 and the level of cytokine production by CD4+ T helper cells in different groups of mice [with or without cancer], also, the effect of invasive aspergillosis on the immune response pattern of cancer mice. Patterns of susceptibility and resistance to infection obtained with different groups of mice injected with Aspergillus fumigatus conidia. TLR-2 and Dectin-1 analyzed applying flowcytometry and cytokine production of cultured splenocytes by ELISA method. Cancer mice that challenged with A. fumigatus conidia showed significant increase in TLR-2 and Dectin-1 levels compared with the two other control groups [normal mice challenged with A. fumigatus and non-infected cancer mice]. Moreover, it showed insignificant decrease in IFN-gamma and IL-10 levels and insignificant increase in TNF-alpha level. The data demonstrated remarkable rise in IL-4 level and the mortality of cancer mice that intravenously infected with A. fumigatus. Probably IA causes stimulation in innate immunity and Th2 cells, also some disorganization in cytokine production in CD4+ T helper cells. We hypothesize that concomitance of IA and cancer may change the microenvironment for local or systemic immune responses. Other complementary studies could help supporting our hypothesis