Photoacoustic imaging of lacZ gene expression in vivo

Abstract

Abstract. In the postgenomic era, imaging techniques are playing an important role in visualizing gene expression in vivo. This work represents the first demonstration of photoacoustic tomography ͑PAT͒ for reporter gene imaging. Rats inoculated with 9L/lacZ gliosarcoma tumor cells are imaged with PAT before and after injection of X-gal, a colorimetric assay for the lacZ-encoded enzyme ␤-galactosidase. Using far-red optical illumination, the genetically tagged tumors in rats are clearly visualized by PAT following the assay. The spatial resolution is quantified to be less than 400 m, while 500-nM-level sensitivity is demonstrated. With the future development of new absorption-based reporter gene systems, it is anticipated that photoacoustic technology will provide a valuable tool for molecular imaging research.

Simultaneous Molecular and Hypoxia Imaging of Brain Tumors In Vivo Using Spectroscopic Photoacoustic Tomography

“…SPAT holds promise for noninvasive monitoring of pathological or physiological reactions (e.g., apoptosis) at the cellular and molecular level. In addition, SPAT is applicable to imaging of gene expression [46] or to monitoring of delivery of vectors to specific cells in gene therapy. We anticipate that SPAT will make profound contributions to the molecular imaging in general.…”

Realtime photoacoustic microscopy in vivo with a 30-MHz ultrasound array transducer

“…Unique to photoacoustic methods is the ability to image blood oxygen saturation as well as concentration of total hemoglobin [11][12][13]. Emerging photoacoustic methods are enabling molecular imaging in small animals, including imaging of gene expression [14] and cell receptors [15]. Unfortunately, long scan times are presently required in both scanning PAT and PAM.…”

Biomedical photoacoustics: fundamentals, instrumentation and perspectives on nanomedicine

“…32 Moreover, it offers molecular or genetic functional imaging to accurately measure oxygen saturation and hemoglobin concentration in vivo. 33,34 In virtue of imaging purposes on the gastrointestinal tract and cardiovascular system, PAE exhibits high imaging speed and has a special ultrasonic transducer. Recently, a US transducer for PAE has been upgraded with a diameter of 3.8 mm and a length of 38 mm, which enables the simultaneous US and PAI with a single device.…”