Functional Human CD141+ Dendritic Cells in Human Immune System Mice

Background. For the purpose of studying functional human dendritic cells (DCs) in a humanized mouse model that mimics the human immune system (HIS), a model referred to as HIS mice was established. Methods. Human immune system mice were made by engrafting NOD/SCID/IL2Rgamme(null) (NSG) mice with human hematopoietic stem cells (I ISCs) following the transduction of genes encoding human cytokines and human leukocyte antigen (HLA)-A2.1 by adeno-associated virus serotype 9 (AAV9) vectors. Results. Our results indicate that human DC subsets, such as CD141(+)CD11c(+) and CD1c(+)CD11c(+). myeloid DCs, distribute throughout several organs in HIS mice including blood, bone marrow, spleen, and draining lymph nodes. The CD141(+)CD11c(+) and CD1c(+)CD11c(+). human DCs isolated from IIIS mice immunized with adenoviruses expressing malaria/human immunodeficiency virus (HIV) epitopes were able to induce the proliferation of malaria/HIV epitopes-specific human CD8(+)T cells in vitro. Upregulation of CD1c was also observed in human CD141(+) DCs 1 day after immunization with the adenovirus-based vaccines. Conclusions. Establishment of such a humanized mouse model that mounts functional human DCs enables preclinical assessment of the immunogenicity of human vaccines in vivo.