Shingai, MasashiDonau, Olivia K.Plishka, Ronald J.Buckler-White, AliciaMascola, John R.Nabel, Gary J.Nason, Martha C.Montefiori, DavidMoldt, BrianPoignard, PascalDiskin, RonBjorkman, Pamela J.Eckhaus, Michael A.Klein, FlorianMouquet, HugoCetrulo Lorenzi, Julio CesarGazumyan, AnnaBurton, Dennis R.Nussenzweig, Michel C.Martin, Malcolm A.Nishimura, Yoshiaki2015-04-012014Shingai, M., O. K. Donau, R. J. Plishka, A. Buckler-White, J. R. Mascola, G. J. Nabel, M. C. Nason, et al. 2014. “Passive transfer of modest titers of potent and broadly neutralizing anti-HIV monoclonal antibodies block SHIV infection in macaques.” The Journal of Experimental Medicine 211 (10): 2061-2074. doi:10.1084/jem.20132494. http://dx.doi.org/10.1084/jem.20132494.0022-1007http://nrs.harvard.edu/urn-3:HUL.InstRepos:14351324It is widely appreciated that effective human vaccines directed against viral pathogens elicit neutralizing antibodies (NAbs). The passive transfer of anti–HIV-1 NAbs conferring sterilizing immunity to macaques has been used to determine the plasma neutralization titers, which must be present at the time of exposure, to prevent acquisition of SIV/HIV chimeric virus (SHIV) infections. We administered five recently isolated potent and broadly acting anti-HIV neutralizing monoclonal antibodies (mAbs) to rhesus macaques and challenged them intrarectally 24 h later with either of two different R5-tropic SHIVs. By combining the results obtained from 60 challenged animals, we determined that the protective neutralization titer in plasma preventing virus infection in 50% of the exposed monkeys was relatively modest (∼1:100) and potentially achievable by vaccination.en-USJournal Article2015-04-0110.1084/jem.20132494