Growth characteristics of SHIV without the vpu gene.

NM-3 is a prototype of chimeric virus between simian and human immunodeficiency viruses (SHIV). It grows in monkey lymphocytic cells in vitro and in vivo as well as in human cells. A mutant designated NM3-E65, which lacks expression of the entire vpu gene, was constructed from NM-3, and monitored for its replication property. Examination of growth properties in simian and human cells of SHIV, HIV, and their vpu mutants revealed that the vpu gene in the genome of the chimeric virus is functional, but non-essential for virus replication.