Immunotypes of a quaternary site of HIV-1 vulnerability and their recognition by antibodies.

Vaccine Research Center, NIAID, NIH, 40 Convent Drive, Bethesda, MD 20892, USA.
Journal of Virology (Impact Factor: 4.65). 02/2011; 85(9):4578-85. DOI: 10.1128/JVI.02585-10
Source: PubMed

ABSTRACT HIV-1 is neutralized by a class of antibodies that preferentially recognize a site formed on the assembled viral spike. Such quaternary structure-specific antibodies have diverse neutralization breadths, with antibodies PG16 and PG9 able to neutralize 70 to 80% of circulating HIV-1 isolates while antibody 2909 is specific for strain SF162. We show that alteration between a rare lysine and a common N-linked glycan at position 160 of HIV-1 gp120 is primarily responsible for toggling between 2909 and PG16/PG9 neutralization sensitivity. Quaternary structure-specific antibodies appear to target antigenic variants of the same epitope, with neutralization breadth determined by the prevalence of recognized variants among circulating isolates.

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