STOCK Tg(CD207-cre/ERT2)1Dhka/J

Stock number: 028287
Product name: huLangerin-CreER^T2
Research areas: Cancer Research, Dermatology Research, Developmental Biology Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

The huLangerin-CreER^T2 transgenic mice have tamoxifen-inducible Cre recombinase and human Langerin expression directed to Langerhans cells (LCs) by the human CD207 locus promoter/enhancer regions. This allows deletion of floxed sequences in fully-differentiated LCs.

Detailed description

Langerhans cells (LCs), a subset of the dendritic cell population found in the epidermis, are the first antigen-presenting cells encountering pathogens and antigens at the surface of the skin.


The huLangerin-CreER^T2 transgenic mice express tamoxifen-inducible Cre recombinase (CreER^T2) and human CD207 (huLangerin), both under control of the human CD207 locus promoter/enhancer regions. The huLangerin-CreER^T2 mice from this founder line have highly selective expression within Langerhans cells (LCs); resulting in efficient excision of floxed sequences in response to tamoxifen administration, as well as huLangerin expression, in these cells. In detail, transgene expression (huLangerin expression) was specific for LCs (MHC-II⁺ CD45⁺), and all LCs expressed huLangerin. In the dermis, only migratory LCs (muLangerin⁺ but CD103^-) expressed huLangerin. In skin draining lymph nodes, LCs expressing huLangerin were readily detectable. CreER^T2 efficiency was 75% on day 9 post-treatment (1.0 mg tamoxifen i.p. for 5 consecutive days). CD103+ CD11b+ DC in the lamina propria of the intestines and mesenteric lymph node also show huLangerin expression.
Hemizygous mice are viable and fertile. The donating investigator reports hemizygotes exhibit no gross physical or behavioral abnormalities associated with huLangerin overexpression. To date (January 2016), it has not been attempted to make this strain homozygous.

The Cre-ERT2 fusion protein consists of Cre recombinase fused to a triple mutant form of the human estrogen receptor which does not bind its natural ligand (17β-estradiol) at physiological concentrations but will bind the synthetic estrogen receptor ligands 4-hydroxytamoxifen (OHT or tamoxifen) and, with lesser sensitivity, ICI 182780. Restricted to the cytoplasm, Cre-ERT2 can only gain access to the nuclear compartment after exposure to tamoxifen. To counteract the mixed estrogen agonist effects of tamoxifen injections, which can result in late fetal abortions in pregnant mice, progesterone may be coadministered.

Development

The huLangerin-CreER^T2 transgenic mice were created by Dr. Daniel H. Kaplan (at University of Minnesota). First, the human bacterial artificial chromosome (BAC) RP11-504o1 was obtained containing the langerin gene (CD207). Using homologous recombination/BAC recombineering, an IRES-CreER^T2 sequence was inserted into the 3' UTR of the BAC CD207 gene. The CreER^T2 fusion gene (Cre-ER^T2) is Cre recombinase fused to a G400V/M543A/L544A triple mutation of the human estrogen receptor ligand binding domain. A 61 kbp DNA fragment from the modified BAC was isolated and microinjected into the pronuclei of FVB fertilized eggs. Founder mice were bred to C57BL/6 for approximately two generations, and then to the C57BL/6J-congenic Rosa26.STOP^fl.YFP reporter strain (Gt(ROSA)26Sor^tm1(EYFP)Cos ; Stock No. 006148) to evaluate the specificity and efficiency of CreER^T2-mediated excision. This founder line was found to have highly selective expression of CreER^T2 within Langerhans cells. Later, the mice were bred to TGFβR1^CA (Hprt^{tm1(CAG-Tgfbr1*)Lba}) animals on an undisclosed genetic background.

The donating investigator reports that huLangerin-CreER^T2 transgenic mice with black coat color on a predominantly C57BL/6 genetic background (and also harboring the Rosa26.STOP^fl.YFP and TGFβR1^CA alleles) were sent to The Jackson Laboratory in 2015. Upon arrival, some mice were bred with C57BL/6J inbred mice (Stock No. 000664) for at least one generation (and the two Cre-inducible alleles were removed) to establish our living huLangerin-CreER^T2 mouse colony.

Allele

Symbol: Tg(CD207-cre/ERT2)1Dhka
Name: transgene insertion 1, Daniel H Kaplan
MGI accession ID: MGI:5431679
Generation method: Transgenic
Attributes: Recombinase-expressing; Inducible
Marker symbol: Tg(CD207-cre/ERT2)1Dhka
Marker name: transgene insertion 1, Daniel H Kaplan
Chromosome: UN
Strain of origin: FVB
Expressed genes: cre/ERT2,Cre recombinase and estrogen receptor 1 (human) fusion gene,
Site of expression: Driven by human CD207 promoter/enhancer elements following induction by tamoxifen, Cre/ERT2 fusion protein is expressed within Langerhans cells.
Molecular note: A cassette encoding an IRES-cre/ERT2 sequence was inserted in the 3' UTR of the human langerin (CD207) gene in the bacterial artificial chromosome (BAC) RP11-504O1 by homologous recombination. This generated a 61 kb fragment that was used to produce transgenic mice.