Mouse Body Temperature Measurement Using Infrared Thermometer During Passive Systemic Anaphylaxis and Food Allergy Evaluation

Summary

Here we present a new method to accurately measure body temperature differences in passive systemic anaphylaxis (PSA) and food allergy mouse models using an infrared thermometer. This procedure has been accurately duplicated in previous PSA results.

Abstract

Mouse body temperature measurement is of paramount importance for investigating allergies and anaphylactic symptoms. Rectal probes for temperature readings is common, and they have been proven to be accurate and invaluable in this regard. However, this method of temperature measurement requires the mice to be anesthetized in order to insert the probe without injury to the animal. This limits the ability to observe other phenotypes of the mouse simultaneously. In order to investigate other phenotypes while measuring temperatures, rectal probes are not ideal, and another method is desired. Here, we introduce a noninvasive method of temperature measurement that foregoes the requirement for mouse anesthesia while maintaining equal reliability to rectal probes in measuring body temperature. We use an infrared thermometer that detects body surface temperatures at ranges between 2 and 150 mm. This method of body temperature measurement is successful in reliably replicating temperature change trends during passive system anaphylaxis experiments in mice. We show that body surface temperatures are about 2.0 °C lower than rectal probe measurements, but the degree of temperature drop follows the same trend. Furthermore, we use the same technique to observe mice in a food allergy model to evaluate temperature and activity levels simultaneously.

Introduction

Measurement of body temperature has been an essential part of monitoring the effects of anaphylactic symptoms in animal models^1,2. Temperature differences have been traditionally measured by rectal probe thermometers in mice^3,4. With these measurements, investigators have reliably portrayed differences in temperature among variables; however, this method is a time-consuming procedure and causes distress to mice, which can increase the body core temperature. Rectal probing can also cause mucosal tearing and infection³. Moreover, ....

Protocol

All animal experiments were approved by the Animal Care and Use Committee of the La Jolla Institute for Allergy and Immunology.

1. Mouse Body Temperature Measurement During Anesthetization

1. Place the mouse in an anesthesia induction box. Anesthetize by using 1 L/min flow of oxygen with 5% isoflurane.
   NOTE: Anesthetization is confirmed when the mouse ceases voluntary movement and has been immobile for over 30 s. Alternatively, monitor respiratory rate, and once mice are breathing at 1 breath per every 2 s or longer, anesthetization is confirmed.
2. Hold the mouse by the nape of the neck with an index finger and thumb....

Results

Passive systemic anaphylaxis: For iv injection, 10 week old female BALB/c mice were anesthetized. Prior to the injection, we measured their body temperatures (Video 1) as described in step 1. Figure 1 shows the temperature trend of both populations after iv injection. The IgE-sensitized mouse showed a maximum temperature drop of 3.0 °C at 20 min, while the PBS control mouse had a maximum drop of 1.1 °C at 20 min⁷. Furt.......

Discussion

The protocol described was established with the goal of measuring body temperature without the use of anesthesia. Despite its relative ease with which temperature readings can be obtained, there are several caveats that accommodate this technique, in addition to the more obvious effects such as handling stress and different ambient temperatures.

First, in order to maintain consistent temperature readings throughout the experiment, the location where the temperature is being measured must be pr.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Non-contact infrared thermometer	SinoPie	DT-8861
Anti-dinitrophenyl (DNP) IgE	Sigma Aldrich	D8406-.2MG
PrecisionGlide 30 G needle	BD	305128
PrecisionGlide 26 G needle	BD	305111
1 mL syringe	BD	309659
Dinitrophenyl - human serum albumin	Biosearch Technologies	D-5059-10
Ovalbumin from chicken egg white	Sigma Aldrich	A5503-50G
Imject Alum	ThermoFisher Scientific	77161
Animal Feeding Needles, disposable	Fisher Scientific	01-208-87