Experimental Design

• Hemizygous animals from stock 5493 were separated into 3 groups:– No Doxycycline Supplementation– Doxycycline in MediGel at 2mg/ml– Doxycycline in Acidified 10% Sucrose Drinking Water

• Animals were given supplementation in home cage environment for 7 days

• Animals were sacrificed after 7 days and heart and kidney were stained for β-gal activity

MediGelTM Assisted Doxycycline Administration in a Tet Inducible Reporter Mouse

STOCK Tg(Tek-rtTA,TRE-lacZ)1425Tpr/J; Jax Stock 005493

Fig. 4. Histological analysis of Dox-induced reporter transgene expression in the microvasculature. Tissue samples following X-Gal staining were paraffin embedded, sectioned, and counterstained with Nuclear Fast Red. A: in the heart, reporter transgene expression is uniformly seen in the endocardium in both ventricles and over the tricuspid valves. B–D: small vessels and microvessels express the transgene in the cerebrum (B), lung (C), and within cardiac muscle (D). E: renal expression of the transgene in the afferent arteriole and glomerular capillaries. Note: because of the nuclear localization of the reporter ßGal, only endothelial cells whose nuclei are contained within the section are visualized.

In the presence of tetracycline or a tetracycline analog (such as doxycycline), selective expression of beta-galactosidase is observed in the nuclei of vascular endothelium in a wide variety of tissues (aorta, heart, brain, lung, kidney, liver, spleen, uterus, prostate, stomach, skeletal muscle, large and small intestine). Expression is observed as early as embryonic day 9.5. In the absence of tetracycline, some beta-galactosidase expression occurs in the smaller branches of the aorta.

Physiol Genomics. 2002 Oct 29;11(2):99-107. Inducible and selective transgene expression in murine vascular endothelium.Teng PI, Dichiara MR, Kömüves LG, Abe K, Quertermous T, Topper JN.

No Dox Treatment

DOX Medigel Treatment Heart 20X

Medigel supplemented with doxycycline demonstrates a more uniform expression pattern.

DOX H2O Treatment Heart 20X

No Dox Treatment Heart 20X

No Dox treatment Dox gel kidney Dox H20 kidney