CCMB cracks code of fungus that turns into giant immune-evading cells

Hyderabad's CSIR-CCMB researchers have identified a biological circuit that enables the deadly fungus Cryptococcus neoformans to form giant Titan cells and evade the human immune system, according to a study published in Oxford Academic Genetics in August 2026. The fungus causes nearly one in five AIDS-related deaths globally and can lead to lethal brain infections.

The team, led by Dr Sriram Varahan, discovered that efficient glucose metabolism helps maintain proper calcium levels inside the fungal cell, which in turn activates the calcineurin signalling pathway. This master pathway allows the fungus to survive stress inside the human body and transform into Titan cells. The study reveals that metabolism acts not just as an energy supplier but as a decision-making system that controls the fungus's ability to become more dangerous.

Rather than acting independently, the fungus's energy metabolism, calcium signalling and calcineurin activation work together as a coordinated network. The findings suggest a new therapeutic approach: instead of killing the fungus outright, future drugs could be designed to prevent it from ever producing Titan cells.