Generation of an HLA-DQ2.5 Knock-In Mouse

Abstract

The human MHC class II molecule HLA-DQ2.5 is implicated in multiple autoimmune disorders, including celiac disease, type 1 diabetes, and systemic lupus erythematosus. The pathogenic contribution of HLA-DQ2.5 in many of these disorders is not fully understood. There is thus a need for an HLA-DQ2.5 humanized mouse model with physiological expression of this MHC molecule that can be integrated into disease models. In this article, we report the generation of an HLA-DQ2.5 knock-in mouse strain on a C57BL/6 background in which sequences encoding the extracellular moieties of mouse MHC class II H2-IAa and H2-IAb1 have been replaced with those of HLA-DQA1*05:01 and HLA-DQB1*02:01. In heterozygous knock-in mice, the expression of HLA-DQ2.5 is superimposable with the expression of H2-IA. This was not the case in a regular untargeted HLA-DQ2.5 transgenic mouse. HLA-DQ2.5 in the knock-in animals is functional for T cell development and for Ag presentation to HLA-DQ2.5-restricted and glutenspecific T cells. Because C57BL/6 mice do not express H2-IEa, the only functional MHC class II molecule in homozygous HLA-DQ2.5 knock-in mice is the knock-in gene product. This alleviates the need for crossing with MHC class II knockout mice to study the isolated function of the MHC transgene. Our novel mouse strain provides an important tool to study the involvement of HLA-DQ2.5 in models of diseases with association to this HLA allotype. ImmunoHorizons, 2021, 5: 25-32.

Co-factors, Microbes, and Immunogenetics in Celiac Disease to Guide Novel Approaches for Diagnosis and Treatment

“…Therefore, mice lacking MHCII genes that are transgenic for hCD4 and the HLA-DR3-DQ2 haplotype have been created, with or without the NOD background, through either an untargeted approach 135 or a targeted knock-in where mouse class II was replaced by human HLA-DQ2. 136 On parenteral sensitization and subsequent dietary exposure to gluten, a few DQ2 mice developed IgA anti-TG2 antibodies and gluten-specific CD4þ T cells, though in the absence of significant immunopathology, suggesting additional cofactors or mucosal sensitization as necessary preconditions for villous atrophy in this model as well. Future studies are needed to characterize the spontaneous and induced responses to gluten, as well as requirements for additional cofactors, such as mucosal adjuvants or gut microbiota background, in the DQ2 mice.…”

A high-affinity human TCR-like antibody detects celiac disease gluten peptide–MHC complexes and inhibits T cell activation

“…Currently, there is no HLA-DQ2.5 humanized preclinical model that recapitulates the gluten-dependent immune-mediated enteropathy of CeD. As an approximation, we therefore turned to a mouse model relying on adoptive transfer of naïve CD4 + T cells isolated from HLA-DQ2.5 knock-in (KI)/TCR-glia-α2 transgenic (tg) mice ( 35 ) into HLA-DQ2.5 KI recipient mice ( 36 ). This allowed us to study antigen-specific T cell proliferation in the gut-associated lymphoid tissue and draining mesenteric lymph nodes (MLN) upon oral administration of the antigen (Fig.…”

“…5A). The interface between CDR H1 and HLA-DQ2.5:DQ2.5-glia-2 was mediated by interdigitating interactions of the helix backbone, the side chains of Val 30 and Val 36 at either end of the CDR H1 helical turn and Arg 31 , which further formed a salt bridge with HLA-DQ2.5- Asp 66 , and a H-bond with Q64 (Fig. 5A).…”

TG2-gluten complexes as antigens for gluten-specific and transglutaminase-2 specific B cells in celiac disease

“…Tgm2 -/- mice [ 13 ] mice were kindly provided by Prof. G. Melino. HLA-DQ2.5 tg [ 14 ], HLA-DQ2.5 KI [ 15 ], TCR-glia-α2 tg [ 12 ] and TCR-glia-ω2 tg mice [ 16 ] are described previously. HLA-DQ2.5 tg or heterozygous targeted HLA-DQ2.5 KI mice express both HLA-DQ2.5 and H2-IA and are assumed to be functionally similar [ 15 ].…”

“…HLA-DQ2.5 tg [ 14 ], HLA-DQ2.5 KI [ 15 ], TCR-glia-α2 tg [ 12 ] and TCR-glia-ω2 tg mice [ 16 ] are described previously. HLA-DQ2.5 tg or heterozygous targeted HLA-DQ2.5 KI mice express both HLA-DQ2.5 and H2-IA and are assumed to be functionally similar [ 15 ]. HLA-DQ2.5 tg or heterozygous HLA-DQ2.5 KI mice were crossed to 14E06 double KI-mice to obtain DQ2.5.14E06 mice.…”