A hCXCR1 transgenic mouse model containing a conditional color-switching system for imaging of hCXCL8/IL-8 functions in vivo

Abstract

To address the functions of human CXCL8 (hCXCL8)/IL-8 through hCXCR1 in vivo, we have developed a humanized, transgenic mouse for hCXCR1. This mouse line is versatile and allows for a variety of functional analyses using bioimaging, including Cre/loxP-mediated, tissue-specific hCXCR1 expression in a spatiotemporal manner; a color-switching mechanism, which uses spectrum-complementary, genetically encoded green and red fluorescence markers to label the hCXCR1-expressing cells [enhanced GFP (eGFP)] against the background [monomeric red fluorescent protein (mRFP)]; a bioluminescent marker, which is present in the hCXCR1-expressing cells; and an exogenous cell surface marker (eGFP moiety) in the hCXCR1-expressing cells, which facilitates identification, isolation, and targeting of these cells. The established, transgenic founder line RCLG3A (TG(+)) expresses only mRFP and does so ubiquitously. When the RCLG3A mice are crossed with the tamoxifen-inducible, whole-tissue Cre mice (ROSA26-Cre/Esr(+/-)), administration of tamoxifen induces whole-body hCXCR1 expression and color-switching. When RCLG3A mice are crossed with thymocyte-specific Cre mice (Lck-Cre(+/+)), the hCXCR1 expression and color-switching are restricted in a lineage-specific manner. This mouse line can be used to understand the functions of hCXCL-8 in vivo. In addition, our approach and vectors can be used to establish other tissue-specific, transgenic mice in conjunction with multifunctional cell markers, which facilitate cell imaging, tracing, and manipulation in vivo.

BAP31 is involved in T cell activation through TCR signal pathways

“…Therefore, we generated a BAP31 conditional KO mouse. The Lck proximal promoter becomes most effective in thymocytes starting from the DN3 stage or later333435363738. When Lck-cre transgene was introduced, the effective deletion of target genes started from the DN3 stage and the obvious deletions were often observed from the DN4 stage and on ward29.…”

Overexpression of miR-155 in the Liver of Transgenic Mice Alters the Expression Profiling of Hepatic Genes Associated with Lipid Metabolism

“…A 318bp fragment containing the precursor sequence of the mmu-miR-155 was amplified by PCR from pEμ-mmu-miR155 plasmid [ 12 ], and then directionally cloned into the Mlu I and Sac I sites of the pRLG plasmid [ 13 , 14 ], designated as pRm155LG, followed by identification of PCR, enzyme digestion analysis and sequencing (data not shown).…”

Simple and rapid determination of homozygous transgenic mice viain vivofluorescence imaging

“…One powerful approach is the transgene overexpression of any given gene(s) in genetically engineered mice to explore the role(s) of the gene(s) in vivo . Currently, the conditional transgenic mice are becoming increasingly popular for precisely regulate gene expression in a temporal and/or spatial pattern [ 2 – 4 , 14 , 17 , 18 , 21 – 25 , 28 – 32 ]. These general transgenic constructs carrying fluorescence reporter gene ( Supplementary Table S1 ) can be widely used to readily realize both the conditional (including temporal, spatial or spatiotemporal) and the constitutive (including ubiquitous or organ/tissue/cell-specific) transgene over-expression in transgenic mice.…”

“…To make full use of the above-mentioned advantages of the fluorescent imaging in non-invasively and visually characterizing transgenic mice, some general transgenic vectors have been successfully developed ( Supplementary Table S1 ) and applied for developing transgenic animals used in biomedical research [ 14 , 17 , 18 , 21 – 25 ]. These general transgenic vectors harbor the reporter transgene (i.e., EGFP, RFP, etc) under the transcriptional control of a ubiquitous promoter and carry multiple cloning site (MCS), into which target transgene(s) can be inserted ( Supplementary Table S1 ).…”