B6.Cg-Cd244a^tm1Kmle/SwgnrJ

Stock number: 040348
Product name: 2B4^-
Research areas: Cancer Research, Immunology, Inflammation and Autoimmunity Research, Neurobiology Research

Description

The 2B4^- allele has a neo cassette replacing all of exon 2 and part of exon 3 of the Cd244a gene, abolishing expression of any 2B4 transcript. These mice may be useful for studying lymphocytic activation receptors and the development of immune responses.

Detailed description

The 2B4^- allele has a neo cassette replacing all of exon 2 and part of exon 3 of the CD244 molecule A (Cd244a) gene, abolishing expression of any 2B4 transcript. 2B4 encodes a cell surface receptor expressed on natural killer (NK) cells, T cell, and dendritic cells that mediate non-major histocompatibility complex (MHC) restricted killing. Natural killer (NK) cells are critical in the immune response to tumor cells, virally infected cells, and bone marrow allografts. 2B4 can be either activating or inhibitory depending on surface density of 2B4, level of 2B4 ligation, and binding competition between Signaling lymphocytic activation molecule (SLAM)-associated protein molecules and phosphatases.

2B4^-/- mice are phenotypically normal as are the lymphocyte populations, including NK cell numbers and the NK receptor repertoire. Thymocytes from female 2B4^-/- mice, but not male 2B4^-/- mice, have an increase in the immature CD4^-/CD8^- population.

Development

The 2B4^- targeting vector was designed by Dr. Vinay Kumar (University of Chicago) and Dr. Porunelloor A. Mathew (University of North Texas Health Science Center) to replace all of exon 2 and part of exon 3 of the CD244 molecule A (Cd244a) gene with a neomycin resistance (neo) cassette. The construct was electroporated into B6.Cg-Thy1^a-derived Bruce-4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts and the resulting chimeric mice were bred to B6(Cg)-Tyr^c-2J/J albino mice. 2B4^- mice were intercrossed to produce homozygous 2B4^-/-mice which were backcrossed C57BL/6J mice (Stock No. 000664) for at least 10 generations and the Tyr^c-2J allele was bred out of the colony. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes.

Allele

Symbol: Cd244a^tm1Kmle
Name: targeted mutation 1, Kyung-Mi Lee
MGI accession ID: MGI:3055564
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: 2B4^-
Marker symbol: Cd244a
Marker name: CD244 molecule A
Marker synonyms: 2B4; C9.1; Cd244; F730046O15Rik; NAIL; NKR2B4; Nmrk; SLAMF4
Chromosome: 1
Strain of origin: B6.Cg-Thy1^a
Molecular note: A targeting vector was used to replace the extracellular region, exon 2 and part of exon 3 with a PGK-neo. Flow cytometry indicated that mutant mice did not express the protein.