CD18 KO mice contain a neo cassette inserted into the splice-acceptor site of exon 3 of the Itgb2 (integrin beta 2) gene, abolishing gene expression. Homozygotes are viable and fertile, with some perinatal lethality evident. CD18 (β2 integrin) is a β integrin subunit expressed on hematopoietic cells that can hetrodimerize with distinct CD11 subunits to form CD11a/CD18 (LFA-1), CD11b/CD18 (Mac-1), CD11c/CD18 or CD11d/CD18. β2 integrins play critical roles in various functions depending on the distinct β2 integrin member and the cell subset upon which it is expressed. These functions include cell:cell adhesion, cell trafficking, T cell activation and differentiation, and pathogen clearance . Mice exhibit elevated neutrophil counts, small/hypocellular peripheral lymph nodes, splenomegaly and enhanced susceptibility to infection. These mice demonstrate defects similar to individuals with a disease known as leukocyte adhesion deficiency type 1 (LAD-1).
In an attempt to offer alleles on well-characterized or multiple genetic backgrounds, alleles are frequently moved to a genetic background different from that on which an allele was first characterized. It should be noted that the phenotype of these BALB/cJ-congenic mice could vary from that originally described on a B6;129S7 genetic background.
A targeting vector was designed to insert a neomycin resistance (neo) cassette into the splice-acceptor site of exon 3 of the Itgb2 (integrin beta 2) gene. The construct was electroporated into 129S7/SvEvBrd-Hprt+-derived AB1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts and the resulting chimeric males were bred to C57BL/6J females. These mice were bred to C57BL/6J mice for at least 7 generations before being backcrossed for 9 generations to BALB/cJ mice to generate a colony of CD18 KO mice. Upon arrival at The Jackson Laboratory, mice were bred to BALB/cJ (Stock No. 000651) for at least one generation to establish the colony.
|Allele Name||targeted mutation 2, Baylor College of Medicine|
|Allele Type||Targeted (Null/Knockout)|
|Allele Synonym(s)||beta2-; CD18-; CD18 null; Itgb2-|
|Gene Symbol and Name||Itgb2, integrin beta 2|
|Strain of Origin||129S7/SvEvBrd-Hprt+|
|Molecular Note||A neomycin cassette disrupted the 5' boundary of exon 3. No protein was synthesized from this allele.|
|Mutations Made By|| |
Dr. Arthur Beaudet, Baylor College of Medicine
When maintaining a live colony, homozygous mice may be bred together, although some perinatal lethality has been seen in homozygous offspring.
When using the CD18 KO mouse strain in a publication, please cite the originating article(s) and include JAX stock #027003 in your Materials and Methods section.