PTPRC and hydrops fetalis: However, among the HF diet mice, the livers of mice that were injected with HBV plasmids showed aggravated steatosis compared to those with empty-vector, as indicated by larger areas stained with Oil red O. The numbers of infiltrated inflammatory cells, which were stained positively for leukocyte common antigen CD45, were higher in the HBV-injected mice than in the empty-vector-injected mice.