Regulation of key molecules of immunological synapse by T11TS immunotherapy abrogates Cryptococcus neoformans infection in rats

Inhibition of Microbicidal Activity of Canine Macrophages DH82 Cell Line by Capsular Polysaccharides from Cryptococcus neoformans

Cryptococcus neoformans is a lethal fungus that primarily affects the respiratory system and the central nervous system. One of the main virulence factors is the capsule, constituted by the polysaccharides glucuronoxylomannan (GXM) and glucuronoxylomanogalactan (GXMGal). Polysaccharides are immunomodulators. One of the target cell populations for modulation are macrophages, which are part of the first line of defense and important for innate and adaptive immunity. It has been reported that macrophages can be modulated to act as a "Trojan horse," taking phagocytosed yeasts to strategic sites or having their machinery activation compromised. The scarcity of information on canine cryptococcosis led us to assess whether the purified capsular polysaccharides from C. neoformans would be able to modulate the microbicidal action of macrophages. In the present study, we observed that the capsular polysaccharides, GXM, GXMGal, or capsule total did not induce apoptosis in the DH82 macrophage cell line. However, it was possible to demonstrate that the phagocytic activity was decreased after treatment with polysaccharides. In addition, recovered yeasts from macrophages treated with polysaccharides after phagocytosis could be cultured, showing that their viability was not altered. The polysaccharides led to a reduction in ROS production and the mRNA expression of IL-12 and IL-6. We observed that GXMGal inhibits MHC class II expression and GXM reduces ERK phosphorylation. In contrast, GXMGal and GXM were able to increase the PPAR-γ expression. Furthermore, our data suggest that capsular polysaccharides can reduce the microbicidal activity of canine macrophages DH82.

Therapeutic intervention of glioma with the novel antineoplastic agent T11TS: the story so far

The disease relevance of novel therapeutic agent T11TS, established first by the authors' group, was shown to ameliorate experimental glioma through multimodal mechanistic activities. T11TS reverses immunosuppression in glioma, causing profound effects on immune potentiation via peripheral, intracranial and hematopoietic cells. T-cell signaling in glioma is reversed by T11TS, modulating cytokine levels and favoring apoptotic killing of glioma cells. T11TS arrests the glioma cell cycle at the G1 phase via activation of p21. VEGF downregulation hypophosphorylates the Akt pathway. T11TS hinders endothelial cell progression and metastasis by arresting matrix degradation, inhibiting the Ras-Raf and Akt-PTEN pathways and initiating inflammatory changes, causing apoptosis. T11TS is effective against in vitro human glioma. Toxicity studies demonstrate that T11TS is nontoxic. The authors' study promise translational research with T11TS.