# Mechanistic analysis of Toxoplasma gondii sexual development in tissue culture and mouse models

> **NIH NIH F32** · UNIVERSITY OF WISCONSIN-MADISON · 2024 · $76,756

## Abstract

Project Summary
Toxoplasma gondii is the causative agent of toxoplasmosis, a leading cause of death due to foodborne illness
that causes serious disease in immunocompromised individuals. The parasite develops asexually and
sexually, and asexual parasite development is well-studied. However, the parasite completes its sexual stage
only in the cat intestinal epithelium, presenting a significant ethical and logistical barrier to sexual stage
research. To remove the need for companion animal research and study the unknown biology of sexual stage
T. gondii, our lab developed murine and tissue culture models that support T. gondii sexual development. The
polyunsaturated fatty acid linoleic acid is a critical factor for T. gondii to complete sexual development that is
uniquely elevated in the feline intestine. The mechanisms by which linoleic acid acts on host or parasite remain
unknown. The goal of this proposal is to determine the mechanism of linoleic acid in promoting T. gondii sexual
development in cell culture and in vivo. Preliminary data from our group and others suggests that linoleic acid
acts on both host and parasite to promote a permissive environment for T. gondii sexual development. I
hypothesize that intracellular accumulation of linoleic acid activates T. gondii lipid signaling pathways to
promote sexual development. I further hypothesize that sexual development relies on activation of similar
signaling pathways in the host. In Aim 1, I will determine the mechanism of linoleic acid action on the parasite
by measuring parasite transcriptional responses to linoleic acid treatment. I will also test our new mouse model
of linoleic acid accumulation for its ability to promote efficient T. gondii sexual development in vivo. In Aim 2, I
will use automated image analysis to determine the importance of host cell type in T. gondii sexual
development. siRNA-mediated ablation of linoleic acid-responsive host factors will identify host genes that
influence sexual development. Successful completion of these Aims will better define how linoleic acid enables
growth of T. gondii sexual stages. The long-term implication of this work is a shareable model of T. gondii
sexual development that will help reduce the burden of toxoplasmosis.

## Key facts

- **NIH application ID:** 10903972
- **Project number:** 5F32AI172084-03
- **Recipient organization:** UNIVERSITY OF WISCONSIN-MADISON
- **Principal Investigator:** Nicole Marie Davis
- **Activity code:** F32 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $76,756
- **Award type:** 5
- **Project period:** 2022-09-01 → 2025-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10903972

## Citation

> US National Institutes of Health, RePORTER application 10903972, Mechanistic analysis of Toxoplasma gondii sexual development in tissue culture and mouse models (5F32AI172084-03). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10903972. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*