In Vivo Imaging of NF-κB Activity

Abstract

A wide range of human disorders involves inappropriate regulation of NF-kappaB, including cancers and numerous inflammatory conditions. Toward our goal to define mechanisms through which NF-kappaB leads to the development of disease, we have developed transgenic mice that express luciferase under the control of NF-kappaB, enabling real-time in vivo imaging of NF-kappaB activity in intact animals. We show that in the absence of extrinsic stimulation, strong luminescence is evident in lymph nodes in the neck region, thymus, and Peyer's patches. Treating mice with TNF-alpha, IL-1alpha, or LPS increased the luminescence in a tissue-specific manner, with the strongest activity observed in skin, lungs, spleen, Peyer's patches, and the wall of the small intestine. Liver, kidney, heart, muscle, and adipose tissue displayed less intense activities. Also, exposure of skin to a low dose of UV radiation increased luminescence in the exposed areas. Furthermore, induction of chronic inflammation resembling rheumatoid arthritis produced strong NF-kappaB activity in the affected joints, as revealed by in vivo imaging. Thus, we have developed a versatile model for monitoring NF-kappaB activation in vivo.

Molecular imaging of NF‐kappaB in prostate tissue after systemic administration of IL‐1β

“…The Prostate DOI 10.1002/pros their backs in a light-sealed chamber and imaged as described [17]. Following administration of TNF-a, IL-6, and IL-1b, image monitoring over several hours showed significantly increased NF-kB-dependent luminescence in all these mice (Fig.…”

“…NF-kB-Luciferase transgenic mice developed by Carlsen et al [17] were used in these experiments. The animals were bred and maintained at the AAA-LAC-accredited Animal Resource Facility of Case Western Reserve University.…”

“…All transgenic offspring were crossed with wild type F1 mice to yield NF-kBLuc heterozygous mice with the C57BL/6J genetic background. Identity of transgenic mice was established by PCR-based DNA-screening as previously described [17].…”

“…Luciferase activity in vivo and ex vivo in transgenic mice was assessed as previously described with some modifications [17]. Briefly, imaging of transgenic mice was performed with an ultra-sensitive camera consisting of an image intensifier coupled to a CCD camera of IVIS 150 System Xenogen (Alameda, CA).…”

“…In this study, we sought to determine the net activation of NF-kB in urogenital organs in direct response to acute and prolonged systemic pro-inflammatory cytokine administration using a transgenic mouse with a luciferase reporter under the control of a NF-kB promoter [17]. We used noninvasive techniques, using a light sensitive CCD camera, to serially monitor NF-kB activity in mouse prostate after delivery of proinflammatory agents into the systemic circulation of living transgenic NF-kB-Luciferase mice.…”