High temperature SELMA: evolution of DNA-supported oligomannose clusters which are tightly recognized by HIV bnAb 2G12.
SELMA (SELection with Modified Aptamers) is a directed evolution method which can be used to develop DNA-supported clusters of carbohydrates in which the geometry of clustering is optimized for strong recognition by a lectin of interest. Herein, we report a modification of SELMA which results in glycoclusters which achieve dramatically stronger target recognition (100-fold) with dramatically fewer glycans (2-3-fold). Our first applications of SELMA yielded clusters of 5-10 oligomannose glycans which were recognized by broadly neutralizing HIV antibody 2G12 with moderate affinities (150-500 nM Kd's). In the present manuscript, we report glycoclusters containing just 3-4 glycans, which are recognized by 2G12 with Kd's as low as 1.7 nM. These glycoclusters are recognized by 2G12 as tightly as is the HIV envelope protein gp120, and they are the first constructs to achieve this tight recognition with the minimal number of Man9 units (3-4) necessary to occupy the binding sites on 2G12. They are thus of great interest as immunogens which might elicit broadly neutralizing antibodies against HIV.
Department of Chemistry, Brandeis University , Waltham, Massachusetts, 02454-9110, United States.
J Sebastian
JS
Temme
Iain S
IS
MacPherson
John F
JF
DeCourcey
Isaac J
IJ
Krauss
D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology*; D057134:Antibodies, Neutralizing / Q000737:chemistry / Q000276:immunology*; D001483:Base Sequence; D001666:Binding Sites, Antibody; D000080908:Broadly Neutralizing Antibodies; D004247:DNA / Q000737:chemistry*; D015483:HIV Antibodies / Q000737:chemistry / Q000276:immunology*; D015699:HIV Envelope Protein gp120 / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology; D006358:Hot Temperature; D006801:Humans; D008358:Mannose / Q000031:analogs & derivatives* / Q000276:immunology; D018716:Molecular Mimicry; D008969:Molecular Sequence Data
C529157:2G12 monoclonal antibody; D000911:Antibodies, Monoclonal; D057134:Antibodies, Neutralizing; D000080908:Broadly Neutralizing Antibodies; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; D004247:DNA; D008358:Mannose