A new humanized HLA transgenic mouse model of multiple sclerosis expressing class II on mouse CD4 T cells

Among all the genetic factors associated with susceptibility to multiple sclerosis (MS), the strongest association has been seen with expression of certain major histocompatibility complex (MHC) class II molecules, although analysis of their exact function remains complicated. In general, the expression of class II is restricted to professional antigen-presenting cells; however, human but not mouse CD4+ T cells express class II on their surface. Functional studies of class II+ CD4+ T cells have been hampered due to lack of a proper animal model. Here, we describe development and characterization of a new humanized class II transgenic (tg) mouse expressing HLA-DR3 on mouse endogenous class II-negative background.