CD4 and HIV-1 infection: For example, the bi-specific antibody 10E8.4/iMab which targets the MPER epitope of Env and the host CD4 molecule has demonstrated exquisite breadth and potency when tested against large multiclade panels of viruses (100% breadth with mean IC50 values of 0.002 μg/ml) and protection of humanized mice against HIV-1 infection (95).