Doria-Rose, N. A.,Klein, R. M.,Daniels, M. G.,O'Dell, S.,Nason, M.,Lapedes, A.,Bhattacharya, T.,Migueles, S. A.,Wyatt, R. T.,Korber, B. T.,Mascola, J. R.,Connors, M.

Induction of antibodies that neutralize a broad range of human immunodeficiency virus type 1 (HIV-1) isolates is a major goal of vaccine development. To study natural examples of broad neutralization, we analyzed sera from 103 HIV-1-infected subjects. Among progressor patients, 20% of sera neutralized more than 75% of a panel of 20 diverse viral isolates. Little activity was observed in sera from long-term nonprogressors (elite controllers). Breadth of neutralization was correlated with viral load, but not with CD4 count, history of past antiretroviral use, age, gender, race/ethnicity, or route of exposure. Clustering analysis of sera by a novel method identified a statistically robust subgrouping of sera that demonstrated broad and potent neutralization activity.