Surface expression of H-2 transgenes is regulated by genomic elements outside of sequences encoding peptide binding domains.

<p>(A) The mean fluorescence intensity (MFI) for peripheral blood lymphocytes stained with the H-2D^b specific antibody B22.249 from H-2^b haplotype mice (white) and transgenic mice (gray); (* Line 1 v. B10 or FVB D^b, p<0.05, ^a Line 2 v. B10 or FVB D^b, p<0.05). (B) Splenocytes from mice infected with TMEV for 21 days were isolated and tested by flow cytometry for H-2D^b expression levels using B22.249.R1 labeled with FITC. Data are expressed as the MFI of the FITC labeled cells (* p<0.05, Two-way ANOVA). (C) The same splenocytes in (B) were co-stained with AF6-88.5 labeled phycoerythrin to determined expression of the H-2K^b present on the chimeric K^bα1α2D^b molecule. Data are expressed as MFI of PE labeled cells (* p<0.001, Two-way ANOVA). (D) Brain resident cells from FVB, FVB D^b and FVB K^bα1α2D^b mice were isolated from naïve mice and analyzed by flow cytometry. Side-scatter and forward-scatter were analyzed for the presence of mononuclear resident cells using a lymphocyte gate. Resident antigen-presenting cells were further analyzed by a CD45 mid-level staining gate and assessed for expression of MHC class I. FVB (green), FVB D^b (black) and FVB K^bα1α2D^b (blue) brain cells were assessed for H-2D^b expression by FACS (* p<0.001, t-test). (E) Brain cells isolated from 6 day TMEV infected mice were gated as in (D) and assessed for changes in H-2D^b expression by FACS. Data are the MFI for H-2D^b-FITC.