B6.Cg-Ptprc^a Pepc^b Tg(TcraBC10,TcrbBC10)3Chi/J

Stock number: 027509
Product name: Cor93 TCR transgenic line BC10.3
Research areas: Cancer Research, Immunology, Inflammation and Autoimmunity Research, Internal/Organ Research, Research Tools, Virology Research

Description

The Cor93 TCR transgenic line BC10.3 has a CD8⁺ T cell repertoire that is specific for the K^b-restricted COR93 epitope (hepatitis B virus core/nucleocapsid protein residues 93-100 [MGLKFRQL]), as well as the CD45.1 allele. These mice may be useful in studying cellular mechanisms of CD8⁺ T cell immunity, memory and protection from HBV; especially early events in the host-virus relationship that determine the outcome of hepatotropic human-virus infections.

Detailed description

In humans, the hepatitis B virus (HBV) causes acute and chronic hepatitis and hepatocellular carcinoma. Clearance of HBV requires functional virus-specific CD8⁺ T cell responses.
The Cor93 TCR transgenic line BC10.3 is a C57BL/6-congenic (H-2^b) mouse strain carrying T cell receptor α and β transgenes that recognize a K^b-restricted COR93 epitope (residues 93-100 [MGLKFRQL] of the HBV core protein [HBcAg]). These mice have a CD8⁺ T cell repertoire (greater than 98% of the splenic CD8⁺ T cells) that is specific for the COR93 epitope. The COR93-specific CD8⁺ T cells are immunologically naive with respect to their cognate antigen.
Hemizygous mice are viable and fertile. To date (July 2015), it has not been attempted to make this strain homozygous.

Cor93 TCR transgenic line BC10.3 mice are further modified with the CD45.1 allele (Ptprc^a), rather than the alternate allele normally present in C57BL/6 or BALB/c inbred mice. As CD45 is expressed on all adaptive and innate immune cells, the presence of Ptprc^a in this strain can be used to distinguish the TCR transgenic mouse-derived cell populations from syngeneic host and/or other mice with the alternate allele via anti-CD45.1 antibody staining or flow cytometry.

Development

The Cor93 TCR transgenic line BC10.3 was designed by Dr. Francis V. Chisari (The Scripps Research Institute). To generate the T cell clones, CB6F1 hybrid mice (BALB/c [H-2^d] x C57BL/6 [H-2^b]) were immunized by standard DNA-prime/vaccinia boost immunization to induce a hepatitis B virus (HBV) core/nucleocapsid (HBcAg)-specific CD8⁺ T cell response. The resulting K^b-restricted CD8⁺ cytotoxic T lymphocytes (CTL) clone "BC10" was found to recognize an epitope located between residues 93-100 in the HBcAg (COR93; MGLKFRQL). The identity of the T cell receptor (TCR) Vα and Vβ chains on the surface of the "BC10" T cells was found to be Vα13.1 JαNEW06 and Vβ8.1 Jβ1.2. These TCR sequences were cloned into TCR cassette expression vectors (pTα and pTβ), and the resulting constructs (~15.1 kbp Tα COR93 BC10 transgene and ~17.4 kbp Tβ COR93 BC10 transgene) were co-microinjected into fertilized (BALB/cByJ x C57BL/6J)F2 oocytes. Founder mice were bred with C57BL/6J for germline transmission, and mice from line 3 (lineage BC10.3) were found to have a superior allelic exclusion rate. The Cor93 TCR transgenic line BC10.3 colony was backcrossed for six generations to C57BL/6J inbred mice (H-2^b), and then mated 12 generations with C57BL/6 CD45.1 mice (derived from Stock No. 002014; B6.SJL-Ptprc^a Pepc^b/BoyJ). After this, the colony was maintained by crossing transgenic male or female mice with wildtype (non-transgenic) siblings, and concurrently made homozygous for the CD45.1 allele (Ptprc^a). In 2015, black males hemizygous for the transgene and homozygous for CD45.1 were sent to The Jackson Laboratory Repository. Upon arrival, males were used to cryopreserve sperm. To establish the living mouse colony, an aliquot of the frozen sperm is used to fertilize oocytes from B6.CD45.1 females (Stock No. 002014).

Of note, the donating investigator reports that, at least once during backcrossing, a hemizygous female was bred to a C57BL/6J inbred male (thus the Y chromosome of the congenic strain is of C57BL/6J origin).

Allele

Symbol: Pepc^b
Name: b variant
MGI accession ID: MGI:4819861
Generation method: Not Applicable
Marker symbol: Pepc
Marker name: peptidase C
Chromosome: 1
Strain of origin: Not Applicable
Molecular note: The Pepc gene controls electrophoretic variation of peptidase C (PEP-C; EC 3.4.11.-) of red blood cells. The allele Pepc^b determines a faster migrating band and is found in the CBA/J and A/He strains.

Allele

Symbol: Ptprc^a
Name: a variant
MGI accession ID: MGI:4819849
Generation method: Not Applicable
Marker symbol: Ptprc
Marker name: protein tyrosine phosphatase, receptor type, C
Chromosome: 1
Strain of origin: Not Applicable
Site of expression: Widely expressed on all adaptive and innate immune cells.
Molecular note: Ptprc^a is found in strains SJL/J, STS/A, and DA. Ptprc^b is found in strains C57BL/6, C3H/An, DBA/2, AKR, and many others (J:13367, J:12054, J:12077, J:8603). Twelve nucleotide differences between the a and b alleles have been identified. These base substitutions correspond to five amino-acid changes within the extracellular domain of the encoded protein. These amino-acid differences are clustered in a region that also contains the greatest divergence between mouse and rat sequences (J:22485).

Note that the allele designations originally described were reversed in 1987 (J:8603); all publications prior to 1987 show SJL/J, STS/A, and DA as having the b allele and the C57BL/6J group as having the a allele (J:22341).

Allele

Symbol: Tg(TcraBC10,TcrbBC10)3Chi
Name: transgene insertion 3, Francis Chisari
MGI accession ID: MGI:5648061
Generation method: Transgenic
Attributes: Inserted expressed sequence
Marker symbol: Tg(TcraBC10,TcrbBC10)3Chi
Marker name: transgene insertion 3, Francis Chisari
Chromosome: UN
Strain of origin: BALB/cByJ or C57BL/6J
Expressed genes: Tcra,T cell receptor alpha chain,mouse, laboratory; Tcrb,T cell receptor beta chain,mouse, laboratory
Molecular note: Rearranged Valpha13.1 JalphaNEW06 and Vbeta8.1 Jbeta1.2 were obtained from K-restricted CD8<+> cytotoxic T lymphocyte clone BC10 which recognizes an epitope located between residues 93-100 in the hepatitis B virus core/nucleocapsid (COR93). TCR sequences were cloned into TCR cassette expression vectors (pTalpha and pTbeta) and co-injected.
General note: TCR expression cassettes into which the TCRalpha and TCRbeta cDNA sequences had been cloned were co-injected into (BALB/cByJ x C57BL/6J)F2 fertilized oocytes.