# Thermosensation in skin-penetrating parasitic nematodes

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA LOS ANGELES · 2021 · $656,121

## Abstract

PROJECT SUMMARY
Skin-penetrating nematodes, including the human threadworm Strongyloides stercoralis, are parasitic
roundworms that infect nearly one billion people worldwide. They are intestinal parasites that cause chronic
gastrointestinal distress as well as stunted growth and long-term cognitive impairment in children. Infections with
S. stercoralis can be fatal for immunosuppressed individuals. Despite the health burden caused by parasitic
nematodes, many aspects of their basic biology remain poorly understood. In particular, remarkably little is
known about how parasitic nematodes respond to host-emitted sensory cues. In this proposal, we will investigate
how parasitic nematodes respond to heat. Heat is emitted by all mammals and is a robust sensory cue for many
parasites, including nematodes. We will investigate how heat triggers two different steps of the parasite-host
interaction: host seeking, the process whereby the soil-dwelling infective larvae actively search for hosts to infect;
and activation, the process whereby the infective larvae exit their developmentally arrested state and resume
growth after entering the host. First, we will conduct a quantitative analysis of the temperature-driven host-
seeking behaviors of S. stercoralis (Aim 1). Second, we will elucidate the molecular and cellular mechanisms
that underlie these behaviors (Aim 2). Third, we will investigate the molecular and cellular mechanisms by which
heat triggers activation (Aim 3). These experiments will leverage our recent development of a CRISPR-Cas9
system for targeted mutagenesis in S. stercoralis, allowing us to identify genes required for host seeking and
activation. Together, our results will provide fundamental insights into how sensory responses shape the
interactions of parasitic nematodes with their hosts.

## Key facts

- **NIH application ID:** 10177853
- **Project number:** 5R01AI136976-03
- **Recipient organization:** UNIVERSITY OF CALIFORNIA LOS ANGELES
- **Principal Investigator:** ELISSA ANYON HALLEM
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $656,121
- **Award type:** 5
- **Project period:** 2019-07-22 → 2023-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10177853

## Citation

> US National Institutes of Health, RePORTER application 10177853, Thermosensation in skin-penetrating parasitic nematodes (5R01AI136976-03). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10177853. Licensed CC0.

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