Structure of the human/mouse CD4 transgenes and summary of expression data.

Symbols are as follows: human (black bar) and mouse (open bar) sequences; mouse enhancer (stippled bar), human and mouse promoters (hP, mP); and human and mouse silencer (Si, mSi). Restriction sites: E,EcoRI; Bg, BglII; H, HindIII; X,XbaI; RV, EcoRV; Sc, SacI; Sl,SalI. Expression in different subsets of cells is shown as + for expression, − for no expression, and ± for expression on a low number of cells. Double-positive (DP) CD4⁺CD8⁺ thymocytes; single-positive (SP) peripheral lymphocytes CD4⁺ and CD8⁺; B cells (B); macrophages (MAC); dendritic cells (DC); myeloid (M) and lymphoid (L) DCs; nd, not done.