Biosciences Research Seminar - Deciphering the role of titan cells during Cryptococcus neoformans infection

Meningitis caused by the fungal pathogen Cryptococcus neoformans affects half a million people and kills over 181,000 annually, mostly people with weakened immunity, such as those with cancer, organ transplant recipients and HIV/AIDS patients. Therefore, new strategies to improve outcome of Cryptococcus infection are urgently needed. A better understanding of Cryptococcus pathogenesis is key to identify new drug targets that will offer much needed disease management strategies.

Upon inhalation into the lungs C. neoformans differentiates into cells with varying sizes and morphological characteristics including Titan cells, typical, titanide and drop cells. Titan cells are enlarged (10-100 µm) whereas titanide and drop cells are small (less than 4 µm) compared to typical-size C. neoformans cells (5-7 µm). These titan cells have been observed both in human samples and in mouse model of cryptococcosis. In this seminar I will discuss our recent work on characterising the role of titan cells during Cryptococcus infection. Our work showed that titan cells play a crucial role in the overall virulence of C. neoformans, immune evasion, and resistance to various stresses including resistance to antifungal drugs.