Human Anti-HIV-1 gp120 Recombinant Antibody (clone 2.2c) (CAT#: PABL-161)

Figure 1 Representative ADCC curves for MAbs N5-i5 and 2.2c.

ADCC assays were performed using CEM-NKr-CCR5 target cells sensitized with gp120 of the HIV-1BaL isolate.

Acharya, P., Tolbert, W. D., Gohain, N., Wu, X., Yu, L., Liu, T.,... & Luongo, T. S. (2014). Structural definition of an antibody-dependent cellular cytotoxicity (ADCC) response implicated in reduced risk for HIV-1 infection. Journal of virology, JVI-02194.

Figure 2 Exposure of N5-i5 and 2.2c epitopes on a viral trimer.

(A) Colocalization of N5-i5 and 2.2c epitopes within the virion-associated untriggered HIV-1 trimers. The Cα atoms of gp120 residues involved in interaction with N5-i5 (blue balls) and 2.2c (pink balls) are mapped into the trimer structure derived by cryo-electron tomography and are shown as blue and pink balls, respectively. (B) Colocalization of N5-i5 and 2.2c epitopes within HIV-1 trimers triggered with the soluble CD4. N5-i5 and 2.2c epitope footprints were mapped in the structure derived by cryo-electron tomography of the gp120Bal-d1d2CD4 trimer. The mapping of N5-i5 and 2.2c epitope footprints in the tomograms confirms that they stay largely within the interface of d1d2CD4-triggered spike and are not available for antibody recognition, due to steric hindrance. (C) The binding curves of MAb N5-i5 (red line) and 2.2c (green line) to surface-expressed HIV-1BaL trimers in the presence or absence of soluble d1-d4CD4 (sCD4). CD4i antibody 17b (cyan line) was used as a positive control. The enhancement of binding to sCD4-triggered HIV-1BaL trimers was observed only for coreceptor binding site MAb 17b. (D) MAb N5-i5 binding (solid lines) and 2.2c binding (dashed lines) to CEM-Nkr-CCR5+ cells (left) or CEM-Nkr-CCR5− cells (right). The rightmost curves (red) in each histogram overlay represent the binding of N5-i5 or 2.2c to virion-sensitized cells, whereas the leftmost curves (blue) represent the binding of these MAbs on cells not sensitized with virions.

Acharya, P., Tolbert, W. D., Gohain, N., Wu, X., Yu, L., Liu, T.,... & Luongo, T. S. (2014). Structural definition of an antibody-dependent cellular cytotoxicity (ADCC) response implicated in reduced risk for HIV-1 infection. Journal of virology, JVI-02194.

Figure 3 MAb N5-i5 and 2.2c binding to the gp120 antigen.

(A) Superimposition of N5-i5 Fab-gp12093TH057 coree-d1d2CD4 and 2.2c Fab-gp12089.6P coree-d1d2CD4 complexes. Structures were aligned based on the gp120 molecule; a molecular surface is displayed over N5-i5 Fab, and 2.2c Fab is shown in a ribbon diagram. (B) MAb N5-i5 and 2.2c binding kinetics to gp120-sensitized CEM-Nkr-CCR5+ target cells, as measured with an unlabeled MAb competition protocol. CEM-Nkr-CCR5+ target cells were sensitized with gp120, and a saturation curve was developed as described in Materials and Methods. (C) Scatchard plots of N5-i5 and 2.2c binding to CEM-Nkr-CCR5+ target cells were derived from the binding data using the standard equation by nonlinear curve fitting.

Acharya, P., Tolbert, W. D., Gohain, N., Wu, X., Yu, L., Liu, T.,... & Luongo, T. S. (2014). Structural definition of an antibody-dependent cellular cytotoxicity (ADCC) response implicated in reduced risk for HIV-1 infection. Journal of virology, JVI-02194.

Figure 4 Fv-swapped versions of N5-i5 and 2.2c.

(A) Design of Fv-swapped versions of N5-i5 and 2.2c. Swaps were made by moving the variable heavy (VH) domain onto the constant light (CL) domain and the variable light (VL) domain onto the constant heavy 1 (CH1) domain for each MAb to replicate the Fc domain orientations of counterpart. (B) Half-maximal binding of MAbs N5-i5 and 2.2c and their swapped versions to gp120-sensitized CEM-Nkr-CCR5+ target cells. Each binding experiment was repeated independently four to seven times as described in Materials and Methods, and half-maximal-binding and Bmax values were pooled for statistical analysis. (C) Cytotoxicity mediated by MAbs N5-i5 and 2.2c and their swapped versions on gp120-sensitized CEM-Nkr-CCR5+ target cells.

Acharya, P., Tolbert, W. D., Gohain, N., Wu, X., Yu, L., Liu, T.,... & Luongo, T. S. (2014). Structural definition of an antibody-dependent cellular cytotoxicity (ADCC) response implicated in reduced risk for HIV-1 infection. Journal of virology, JVI-02194.