Subcutaneous Administration of D-Luciferin is an Effective Alternative to Intraperitoneal Injection in Bioluminescence Imaging of Xenograft Tumors in Nude Mice

Ashraf A Khalil,Elisabeth Rosenberg,Theodore D Chung,Kristoffer Valerie,William C Broaddus,Sarah E Golding,Seth M Dever,Mark J Jameson

doi:10.1155/2013/689279

Abstract

Currently, intraperitoneal (IP) injection of D-luciferin is the preferred method of providing substrate for bioluminescent imaging (BLI); however it has a failure rate of 3-10% due to accidental intestinal injection. The present study evaluates the quality of BLI after subcutaneous (SC) injection of D-luciferin and demonstrates the effectiveness of SC injection in anatomically disparate tumor models. Mice bearing luciferase-expressing tumors underwent BLI after SC or IP injection of D-luciferin. The average time to maximal luminescence was 6 min (range 5-9 min) after SC injection and 8 min (range 5-8 min) after IP injection. Within 7 minutes of injection, SC and IP routes yielded similar luminescence in subcutaneous, intracranial, tongue, and lung xenograft tumor models. In a model of combined subcutaneous and intracranial xenografts, SC injection resulted in proportional luminescence at all sites, confirming that preferential delivery of substrate does not occur. While tumors were occasionally not visualized with IP injection, all tumors were visualized reliably with SC injection. Thus, SC injection of D-luciferin is a convenient and effective alternative to IP injection for BLI in nude mice. It may be a preferable approach, particularly for tumors with weaker signals and/or when greater precision is required.

Highlights

Bioluminescence is a naturally occurring phenomenon in certain species such as the firefly resulting from oxidation of luciferin to oxyluciferin in the presence of molecular oxygen and adenosine triphosphate
Bioluminescence imaging (BLI) is an in vivo optical imaging technique that detects light emitted from firefly luciferaseexpressing cells by special charge coupled device (CCD) camera [2]
The evolution of BLI of human xenografts in immunocompromised mice has been driven by the predominant use of this animal model in cancer biology research

Summary

Introduction

Bioluminescence is a naturally occurring phenomenon in certain species such as the firefly resulting from oxidation of luciferin to oxyluciferin in the presence of molecular oxygen and adenosine triphosphate. This reaction is catalyzed by the enzyme luciferase and results in the emission of light [1]. Bioluminescence imaging (BLI) is an in vivo optical imaging technique that detects light emitted from firefly luciferaseexpressing cells by special charge coupled device (CCD) camera [2] This is an extremely valuable experimental tool in cancer biology [3]; noninvasive whole body BLI allows repeated, real-time, and in vivo monitoring of tumors in experimental animal models, regardless of tumor location [2, 4]. The study demonstrates that SC injection is an easy and effective route of administration for D-luciferin with a rapid-onset and reproducible BLS regardless of tumor location

Materials and Methods

Result and Discussion

Findings

Conclusion