Monitoring Pulmonary Nodule Progression Using Micro-Computed Tomography and Blood Sampling in a Mouse Model

Summary

This protocol describes an efficient, simple, and minimally invasive method for studying pulmonary nodules. Submaxillary vein blood collection and micro-CT imaging are used as investigative techniques.

Abstract

Micro-computed tomography (micro-CT) is a real-time, intuitive, sensitive, and minimally invasive technique for monitoring changes from pulmonary nodules (PN) to lung cancer (LC). The integration of submandibular vein blood sampling enables rapid, stable, and straightforward detection of imaging and key target alterations during the progression of PN to LC. In this study, we administered a dosage of 100 mg/kg of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in A/J mice to develop a lung adenocarcinoma model. Disease progression in the experimental animals was then monitored through submandibular vein blood sampling and micro-CT assay. Experimental results showed the presence of nodular foci in the lungs of some animals by the 10^th week, with the development of lung adenocarcinoma images becoming evident by the 21^st week. In conclusion, micro-CT can effectively observe pathological changes in the lungs of mice and, when combined with submandibular vein blood sampling, can dynamically monitor changes in blood, protein, and targets. This method provides a highly specific, simple, and sensitive approach for drug screening, pharmacokinetic testing, toxicological experiments, and safety studies.

Introduction

Lung cancer (LC) is a severe neoplasm originating in the bronchial mucosa or lung glands. According to 2021 statistics, LC causes approximately two million fatalities globally each year, with incidence and mortality rates on the rise¹. Early diagnosis and intervention in LC contribute to higher cure rates, reduced mortality, and lower treatment costs. Pulmonary nodules (PN) are specific precursors to LC, characterized by localized, round, and denser solid or subsolid shadows ≤30 mm in diameter on radiological exams, without evidence of lung collapse, mediastinal lymph node enlargement, or pleural effusion². The Nat....

Protocol

All animal experiments described in this study were approved by the Experimental Animal Welfare Ethics Committee of Chengdu University of Traditional Chinese Medicine and were conducted in accordance with relevant laws and ethical standards for animal research (review number: 2024035). Female inbred A/JGpt mice (7-8 weeks old) were maintained at a temperature of 20-24 °C with a relative humidity of 40%-70%. They were provided with standard animal feed and purified water ad libitum throughout a 12-h light-da.......

Discussion

It is important to reiterate several key points from this study. Firstly, although submandibular vein blood collection is a relatively low-injury procedure, it may still result in some degree of harm to the animals. Therefore, it is necessary to conduct multiple procedures to reduce the burden on the mice and complete the process in a timely manner²⁷. Secondly, the removal of hair prior to blood sample collection ensures the purity of the sample. Thirdly, it is imperative to use appropriate blood .......

Materials

Name	Company	Catalog Number	Comments
A/J mice	GemPharmatech LLC.	N000018
0.5 mL EDTA tubes	Labshark	130201070
1-Butanone,4-(methylnitrosoamino)-1-(3-pyridinyl)	Gu Shi Gong Yuan Medical Equipment Co.	N589770
75% ethanol	ChengDu Chron Chemicals Co,.Ltd	2023052901
Animal shaver	Codos	BM010220
Isoflurane	Shenzhen Reward Life Technology Co.	R510-22-16
medical tricorder	MedChemexpress	69652
Quantum GX2 microCT imaging system	PerkinElme	2020166501
Saline (medicine)	Beijing Biolabs Technology Co.	GL1736‌