USF Researchers Use Neon Fluorescent Imaging To Map Parasite Cell Cycle And Identify New Drug Targets For Toxoplasmosis

USF researchers use neon green fluorescent tags to map the unusual "forked" cell cycle of the Toxoplasma parasite, opening new doors for brain cyst treatments.

By: AXL Media

Published: Mar 21, 2026, 7:50 AM EDT

Source: Information for this report was sourced from University of South Florida

Visualizing a Global Microscopic Threat

A team of researchers at the USF Health Morsani College of Medicine has successfully bypassed the physical limitations of studying Toxoplasma gondii, a parasite that infects nearly one-third of the world's population. Due to its microscopic size and complex behavior, the organism has historically been difficult to observe during its reproductive stages. By adapting a fluorescent imaging system traditionally used for human cells, the USF team can now monitor the parasite's functions in real time. This advancement, published in the journal Bio-Protocol, provides a critical window into the life cycle of an organism that affects both humans and livestock globally.

The Danger of Chronic Toxoplasmosis

While acute toxoplasmosis is often mild, the infection poses severe risks to pregnant women and individuals with compromised immune systems. Associate Professor Elena Suvorova noted that current drug treatments, while effective in the early stages, can be toxic if used long-term. If the infection is not neutralized within the first two weeks, the parasite enters a chronic stage, forming protective cysts within the brain. In this state, the parasite becomes invisible to the human immune system and remains incurable with existing medical protocols. The ability to visualize the parasite's growth is seen as the first step toward developing safer, stage-specific therapies.

Mapping an Unusual Reproductive Pattern

Unlike typical human cells that grow and copy DNA in a linear sequence, Toxoplasma follows a highly irregular reproductive path. Research scientist Mrinalini Batra explained that while scientists understood the parasite must reproduce, the specific arrangement of its growth stages remained a mystery. The USF study revealed that the parasite’s cell cycle resembles a "fork" structure. It begins with a single, straight "handle" of growth before branching into several simultaneous "prongs." This allows the parasite to undergo up to three different cell cycle phases at once, facilitating rapid multiplication and evasion of host defenses.