# Protocol for genetic manipulation of cervical lymph node-innervating nociceptive neurons in mice via retrograde viral tracing

## TL;DR

This paper provides a detailed surgical protocol for genetically manipulating neurons that innervate cervical lymph nodes in mice to study neuroimmune interactions.

## Contribution

A novel protocol for retrograde viral tracing to target and manipulate cervical lymph node-innervating nociceptive neurons in mice.

## Key findings

- The protocol enables precise genetic manipulation of cervical lymph node-innervating neurons.
- Retrograde AAV microinjection allows for labeling and chemogenetic inhibition of these neurons.
- Viral transduction can be verified in the trigeminal ganglia for experimental validation.

## Abstract

This protocol details the surgical procedure for genetically manipulating cervical lymph node (LN)-innervating nociceptive neurons in mice. We describe steps for exposing cervical LNs, microinjecting retrograde adeno-associated viruses (AAVs), and verifying viral transduction in the trigeminal ganglia. This approach enables specific labeling, chemogenetic inhibition, or gene knockout in LN-innervating neurons to study neuroimmune crosstalk.

For complete details on the use and execution of this protocol, please refer to Zhang et al.1

•Instructions for microsurgical exposure of mouse cervical lymph nodes•Steps for precise retrograde viral microinjection into cervical nodes•Guidance on verifying viral expression in trigeminal ganglia neurons

Instructions for microsurgical exposure of mouse cervical lymph nodes

Steps for precise retrograde viral microinjection into cervical nodes

Guidance on verifying viral expression in trigeminal ganglia neurons

Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

This protocol details the surgical procedure for genetically manipulating cervical lymph node (LN)-innervating nociceptive neurons in mice. We describe steps for exposing cervical LNs, microinjecting retrograde adeno-associated viruses (AAVs), and verifying viral transduction in the trigeminal ganglia. This approach enables specific labeling, chemogenetic inhibition, or gene knockout in LN-innervating neurons to study neuroimmune crosstalk.