Tg(HLA-DRB1)31Dmz

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 DRB1*0401 (DR4Dw4) replaced the corresponding alpha1 (aa 1-85) and beta1 (aa 1-96) domains of the H2-Ea and H2-Eb1 genes that make up mouse I-Ed. The native murine promoters were left intact. These transgene constructs were co-injected into fertilized eggs. Flow cytometry analysis indicates that virtually all B-cells and macrophages co-express the chimeric MHC class II molecules. The MHC class II chimeric molecules can be physiologically regulated as there is a 3-4 fold increase in MHC II molecules when splenic B-cells are cultured overnight with IL-4. (J:96129)