STOCK Tg(HLA-DRA*0101,HLA-DRB1*0101)1Dmz Tg(TcraTcrb)1Lkm/J

Stock number: 026566
Product name: DR1-TCR Tg
Strain synonyms: (DR1-TCR) Tg
Research areas: Immunology, Inflammation and Autoimmunity Research

Description

This double transgenic mouse strain carries both an HLA-DR1 transgene and an HLA-DR1-restricted collagen-specific TCR. It was developed to obtain large numbers of antigen-specific T cells that can be used for immunological studies of rheumatoid arthritis.

Detailed description

Autoreactive T cells escaping thymic selection orchestrate joint inflammation in rheumatoid arthritis (RA). They are difficult to study due to the small numbers of antigen-specific cells that are produced. This double transgenic mouse containing both the HLA-DR1 transgene and an HLA-DR1-restricted collagen-specific TCR was developed to obtain large numbers of antigen-specific T cells that can be used for immunological studies.

In vitro, type II collagen (CII)-specific T cells from this mouse proliferate vigorously in response to the CII immunodominant peptide A2 and the cells alter their phenotype to become predominately CD62L^low and CD44^high “activated” T cells. The response is accompanied by the production of Th1, Th2, and Th17-type cytokines.

Following immunization with bovine CII/CFA, these mice develop an accelerated arthritis compared to single transgenic HLA-DR1 mice. They develop a strong T cell-dependent antibody response to the autoantigen, murine CII (mCII), greater than that elicited in control mice bearing only the HLA-DR1 transgene. The increases are pronounced in both immunoglobulin IgG2 and IgG1 subsets. Moreover, offspring from the double transgenic founders develop a more severe form of disease as compared with the HLA-DR1 littermates, as measured by both severity scores and the number of arthritic limbs. Although both groups of mice develop arthritis around 20 days after immunization and continue to progress in severity until the end of published experiments (day 55), severity scores are markedly different. Histology confirms that the double transgenic mice have greater pannus formation and cartilage destruction when compared to arthritic HLA-DR1 mice. Spontaneous arthritis has not been observed in the double transgenic mice up to 24 months of age, despite large numbers of CII-specific T cells.

When the mice are treated orally with the analog peptide A12 (a suppressive analog of collagen), arthritis is significantly suppressed, despite the fact that greater than 90% of the CD4⁺ T cells express the TCR transgene. In gut-associated lymphoid tissues (GALT) taken from A12-treated mice, IL-2, IFN-γ, and IL-17 production to the autoimmune collagen determinant drops while high levels of IL-10 and IL-4 are produced.

This humanized model will be useful for the study of T cell-directed therapies, as well as T cell-mediated mechanisms of autoimmune diseases.

This strain may be segregating for H2^f and H2^b alleles. H2^f has not been found to have any effect on collagen-induced arthritis.

Development

To create the TCR transgene, rearranged Vα2/Jα27 and Vβ8.1/D/Jβ2.4 fragments were obtained from an HLA-DRB1*0101 (DR1)-restricted A2-specific mouse T cell hybridoma (E168) by rt-PCR. The PCR fragments were subcloned into TCR cassette vectors pTαcass and pTβcass. Linearized DNA fragments (pTαcass-Vα2 and pTβcass-Vβ8.1) were simultaneously injected into fertilized eggs of FVB/N mice.

The HLA-DRA*0101,HLA-DRB1*0101 transgene was created as follows: A transgenic construct containing the mouse MHC Class II H2-Ea and H2-Eb1 genes engineered to encode proteins in which the alpha1 domain (amino acids 1-85) and the beta1 domain (amino acids 1-96) were replaced by the corresponding amino acids of the human MHC Class II protein encoded by HLA-DRA1*0101 and HLA-DRB1*0101. Mice were generated by injecting the construct into fertilized (C57BL/6XSJL/J)F2 oocytes. Founder mice were backcrossed for three generations to B10.M-H2^f and then intercrossed to fix the H2^f locus. Cryorecovery at The Jackson Lab may involve C57BL/6J. This strain may be segregating for H2^f and H2^b alleles.

TCR transgenic mice were intercrossed with the HLA-DR1-transgenic mice for six generations to establish a mouse line from which experimental animals hemizygous for the TCR transgene and homozygous for the HLA-DR1 transgene were derived.

Allele

Symbol: Tg(HLA-DRA*0101,HLA-DRB1*0101)1Dmz
Name: transgene insertion 1, Dennis M Zaller
MGI accession ID: MGI:3809457
Generation method: Transgenic
Attributes: Inserted expressed sequence; Humanized sequence
Marker symbol: Tg(HLA-DRA*0101,HLA-DRB1*0101)1Dmz
Marker name: transgene insertion 1, Dennis M Zaller
Chromosome: 5
Strain of origin: (C57BL/6 x SJL/J)F2
Expressed genes: HLA-DRA,major histocompatibility complex, class II, DR alpha,human; HLA-DRB1,major histocompatibility complex, class II, DR beta 1,human
Site of expression: virtually all cells in peripheral blood that express MHC Class II

Molecular note: A chimeric MHC class II complex was created by fusing the human peptide binding domains of class II alpha and beta chains to the CD4 binding domains of murine class II alpha or beta chains. The was done by the construction of two separate transgene constructs. The alpha1 and beta1 domains isolated from human DRA1*0101 and DRB1*0101 replaced the corresponding alpha1 and beta1 domains of the H2-Ea and H2-Eb1 genes that make up mouse I-E^d. The native murine promoters were left intact. These transgene constructs were co-injected into fertilized oocytes and the founder mice with the highest expression of the chimeric MHC was chosen for further propagation. Flow cytometry analysis indicates that virtually all cells in peripheral blood that express endogenous MHC-II also express the chimeric MHC-II. The transgene construct was later shown (in J:126700) to have inserted into chromosome 5.

Allele

Symbol: Tg(TcraTcrb)1Lkm
Name: transgene insertion 1, Linda Myers
MGI accession ID: MGI:5648047
Generation method: Transgenic
Attributes: Inserted expressed sequence
Marker symbol: Tg(TcraTcrb)1Lkm
Marker name: transgene insertion 1, Linda Myers
Chromosome: UN
Strain of origin: FVB/N
Expressed genes: Tcra,T cell receptor alpha chain,mouse, laboratory; Tcrb,T cell receptor beta chain,mouse, laboratory
Molecular note: Rearranged Valpha2-Jalpha27 and Vbeta8.1 Jbeta2.4 fragments were obtained from an HLA-DRB1*0101 (DR1)-restricted A2-specific mouse T cell hybridoma (E168) by RT-PCR. The PCR fragments were subcloned into TCR cassette vectors pTalphacass and pTbetacass and co-injected.