Humanized DRAGA Mice Generation

DRAGA mice express HLA-A2.1 and HLA-DR0401 molecules on a Rag1KO.IL2RγcKO.NOD (NRG) background and they have been previously described [14 (link)]. HLA-A2.1.HLA-DR0401 positive umbilical cord bloods were obtained from the NY Blood Center, Long Island City. Four to six-week old DRAGA mice were irradiated (350 rads) and injected intravenously with CD3 T cell-depleted cord blood cells (EasySep Human CD3 Positive Selection Kit, Stem Cell Technologies, #18051) containing approximately 10⁵ human HSC (CD34⁺) as measured by FACS using human CD34 antibodies (clone#563, BDbiosciences). The procedures for assessing human T and B cell and erythrocyte reconstitution in peripheral blood by FACS have been previously described [8 (link)–10 (link), 14 (link)]. Human albumin plasma levels were measured by ELISA (Human albumin ELISA kit, Bethyl Labs). DRAGA mice were used at 4 months post-infusion of human HSC. As previously reported [14 (link)] most (> 90%) DRAGA mice reconstitute human cells. The human reconstitution status in blood of DRAGA mice used in this study is shown in Additional file 1: Table S1.