Table 1.

Oncolytic viruses encoding reporter transgenes for various imaging modalities

Visualization methods	Reporter transgenes		Oncolytic viruses encoding reporter transgenes	Imaging modalities	Ref.
Optical imaging	Fluorescent proteins (e.g., GFP, eGFP)		Newcastle disease virus, measles virus, herpes simplex virus-1 (HSV-1), adenovirus, vaccinia virus (GLV-1h68), and Vesicular stomatitis virus (VSV)	Specially adapted CCD cameras to detect fluorescence	[25, 29, 33]
	Luciferase		Parvoviruses, adenoviruses, HSV-1, vaccinia virus, measles virus, and VSV	EM-CCD camera
Deep-tissue imaging	Enzyme-mediated imaging (e.g., HSV-1-TK)		Sindbis virus	SPECT and PET scanner, and γ-scintigraphy	[27, 29, 36]
	Receptor-mediated imaging	hSSRT2	Vaccinia virus	PET scanner and γ- scintigraphy	[25, 27, 34, 40]
		D2R	Adenovirus	PET scanner
	Transporter/Symporter-mediated imaging	h-NET	Vaccinia virus (GLV-1h99)	SPECT and PET scanner, and γ-scintigraphy	[42]
		h-NIS	Adenoviruses, measles, vesicular stomatitis, vaccinia virus (GLV-1h153), HSV, and Retrovirus	SPECT and PET scanner, and γ-scintigraphy	[25, 27, 44]

CCD camera Charge-Coupled Device, EMCCD Camera Electron multiplying CCD camera, SPECT single-photon emission computed tomography, PET positron emission tomography