scholarly journals Rational Design of Vaccines to Elicit Broadly Neutralizing Antibodies to HIV-1

2011 ◽  
Vol 1 (1) ◽  
pp. a007278-a007278 ◽  
Author(s):  
P. D. Kwong ◽  
J. R. Mascola ◽  
G. J. Nabel
2021 ◽  
Author(s):  
Colin LaMont ◽  
Jakub Otwinowski ◽  
Kanika Vanshylla ◽  
Henning Gruell ◽  
Florian Klein ◽  
...  

Broadly neutralizing antibodies (bNAbs) are promising targets for vaccination and therapy against HIV. Passive infusions of bNAbs have shown promise in clinical trials as a potential alternative for anti-retroviral therapy. A key challenge for the potential clinical application of bnAbs is the suppression of viral escape, which is more effectively achieved with a combination of bNAbs. However, identifying an optimal bNAb cocktail is combinatorially complex. Here, we propose a computational approach to predict the efficacy of a bNAb therapy trial based on the population genetics of HIV escape, which we parametrize using high-throughput HIV sequence data from a cohort of untreated bNAb-naive patients. By quantifying the mutational target size and the fitness cost of HIV-1 escape from bNAbs, we reliably predict the distribution of rebound times in three clinical trials. Importantly, we show that early rebounds are dominated by the pre-treatment standing variation of HIV-1 populations, rather than spontaneous mutations during treatment. Lastly, we show that a cocktail of three bNAbs is necessary to suppress the chances of viral escape below 1%, and we predict the optimal composition of such a bNAb cocktail. Our results offer a rational design for bNAb therapy against HIV-1, and more generally show how genetic data could be used to predict treatment outcomes and design new approaches to pathogenic control.


2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Lixin Yan ◽  
◽  
Lihong Liu ◽  
Yilin Wang ◽  
Xi Huang ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jean-François Bruxelle ◽  
Tess Kirilenko ◽  
Nino Trattnig ◽  
Yiqiu Yang ◽  
Matteo Cattin ◽  
...  

AbstractThe occurrence of oligomannose-specific broadly neutralizing antibodies (bnAbs) has spurred efforts to develop immunogens that can elicit similar antibodies. Here, we report on the antigenicity and immunogenicity of a CRM197-conjugate of a previously reported oligomannose mimetic. Oligomannose-specific bnAbs that are less dependent on interactions with the HIV envelope protein sequence showed strong binding to the glycoconjugates, with affinities approximating those reported for their cognate epitope. The glycoconjugate is also recognized by inferred germline precursors of oligomannose-specific bnAbs, albeit with the expected low avidity, supporting its potential as an immunogen. Immunization of human-antibody transgenic mice revealed that only a TLR4-stimulating adjuvant formulation resulted in antibodies able to bind a panel of recombinant HIV trimers. These antibodies bound at relatively modest levels, possibly explaining their inability to neutralize HIV infectivity. Nevertheless, these findings contribute further to understanding conditions for eliciting HIV-cross-reactive oligomannose-specific antibodies and inform on next steps for improving on the elicited response.


Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 852
Author(s):  
Ashley Lauren Bennett ◽  
Rory Henderson

The HIV-1 envelope glycoprotein (Env) mediates host cell fusion and is the primary target for HIV-1 vaccine design. The Env undergoes a series of functionally important conformational rearrangements upon engagement of its host cell receptor, CD4. As the sole target for broadly neutralizing antibodies, our understanding of these transitions plays a critical role in vaccine immunogen design. Here, we review available experimental data interrogating the HIV-1 Env conformation and detail computational efforts aimed at delineating the series of conformational changes connecting these rearrangements. These studies have provided a structural mapping of prefusion closed, open, and transition intermediate structures, the allosteric elements controlling rearrangements, and state-to-state transition dynamics. The combination of these investigations and innovations in molecular modeling set the stage for advanced studies examining rearrangements at greater spatial and temporal resolution.


2018 ◽  
Vol 93 (5) ◽  
Author(s):  
Ina Fetzer ◽  
Meredith E. Davis-Gardner ◽  
Matthew R. Gardner ◽  
Barnett Alfant ◽  
Jesse A. Weber ◽  
...  

ABSTRACTBroadly neutralizing antibodies (bNAbs) target five major epitopes on the HIV-1 envelope glycoprotein (Env). The most potent bNAbs have median half-maximal inhibitory concentration (IC50) values in the nanomolar range, and the broadest bNAbs neutralize up to 98% of HIV-1 strains. The engineered HIV-1 entry inhibitor eCD4-Ig has greater breadth than bNAbs and similar potency. eCD4-Ig is markedly more potent than CD4-Ig due to its C-terminal coreceptor-mimetic peptide. Here we investigated whether the coreceptor-mimetic peptide mim6 improved the potency of bNAbs with different epitopes. We observed that when mim6 was appended to the C terminus of the heavy chains of bNAbs, this sulfopeptide improved the potency of all classes of bNAbs against HIV-1 isolates that are sensitive to neutralization by the sulfopeptide alone. However, mim6 did not significantly enhance neutralization of other isolates when appended to most classes of bNAbs, with one exception. Specifically, mim6 improved the potency of bNAbs of the V3-glycan class, including PGT121, PGT122, PGT128, and 10-1074, by an average of 2-fold for all HIV-1 isolates assayed. Despite this difference, 10-1074 does not induce exposure of the coreceptor-binding site, and addition of mim6 to 10-1074 did not promote shedding of the gp120 subunit of Env. Mixtures of 10-1074 and an Fc domain fused to mim6 neutralized less efficiently than a 10-1074/mim6 fusion, indicating that mim6 enhances the avidity of this fusion. Our data show that mim6 can consistently improve the potency of V3-glycan antibodies and suggest that these antibodies bind in an orientation that facilitates mim6 association with Env.IMPORTANCEHIV-1 requires both the cellular receptor CD4 and a tyrosine-sulfated coreceptor to infect its target cells. CD4-Ig is a fusion of the HIV-1-binding domains of CD4 with an antibody Fc domain. Previous studies have demonstrated that the potency of CD4-Ig is markedly increased by appending a coreceptor-mimetic sulfopeptide to its C terminus. We investigated whether this coreceptor-mimetic peptide improves the potency of broadly neutralizing antibodies (bNAbs) targeting five major epitopes on the HIV-1 envelope glycoprotein (Env). We observed that inclusion of the sulfopeptide dramatically improved the potency of all bNAb classes against isolates with more-open Env structures, typically those that utilize the coreceptor CXCR4. In contrast, the sulfopeptide improved only V3-glycan antibodies when neutralizing primary isolates, on average by 2-fold. These studies improve the potency of one class of bNAbs, show that coreceptor-mimetic sulfopeptides enhance neutralization through distinct mechanisms, and provide insight for the design of novel multispecific entry inhibitors.


2021 ◽  
Author(s):  
Yifan Li ◽  
Hongjun Bai ◽  
Eric Sanders-Buell ◽  
Vincent Dussupt ◽  
Samantha Townsley ◽  
...  

Identifying if viral features present in acute HIV-1 infection predetermine the development of neutralization breadth is critical to vaccine design. Incorporating such features in vaccine antigens could initiate cross-reactive antibody responses that could sufficiently protect vaccinees from HIV-1 infection despite the uniqueness of each founder virus. To understand the relationship between Env determinants and the development of neutralization breadth, we focused on 197 individuals enrolled in two cohorts in Thailand and East Africa (RV144 and RV217) and followed since their diagnosis in acute or early HIV-1 infection. We analyzed the distribution of variable loop lengths and glycans as well as the predicted density of the glycan shield and compared these envelope features to the neutralization breadth data obtained three years after infection (n = 121). Our study revealed limited evidence for glycan shield features that associate with the development of neutralization breadth. While the glycan shield tended to be denser in participants who subsequently developed breadth, no significant relationship was found between the size of glycan holes and the development of neutralization breadth. The parallel analysis of 3,000 independent Env sequences showed no evidence of directional evolution of glycan shield features since the beginning of the epidemic. Together, our results highlight that glycan shield features in acute and early HIV-1 infection may not play a role determinant enough to dictate the development of neutralization breadth, and instead suggest that the glycan shield’s reactive properties that are associated with immune evasion may have a greater impact. IMPORTANCE A major goal of HIV-1 vaccine research is to design vaccine candidates that elicit potent broadly neutralizing antibodies (bnAbs). Different viral features have been associated with the development of broadly neutralizing antibodies, including the glycan shield on the surface of the HIV-1 Envelope (Env). Here, we analyzed data from two cohorts of individuals who were followed from early infection to several years after infection spanning multiple HIV-1 subtypes. We compared Env glycan features in HIV-1 sequences obtained in early infection to the potency and breadth of neutralizing antibodies measured one to three years after infection. We found limited evidence of glycan shield properties that associate with the development of neutralization breadth in these cohorts. These results may have important implications for antigen design in future vaccine strategies and emphasize that HIV-1 vaccines will need to rely on a complex set of properties to elicit neutralization breadth.


2018 ◽  
Author(s):  
Alba Torrents de la Peña ◽  
Kimmo Rantalainen ◽  
Christopher A. Cottrell ◽  
Joel D. Allen ◽  
Marit J. van Gils ◽  
...  

AbstractThe HIV-1 envelope glycoprotein (Env) trimer is located on the surface of the virus and is the target of broadly neutralizing antibodies (bNAbs). Recombinant native-like soluble Env trimer mimetics, such as SOSIP trimers, have taken a central role in HIV-1 vaccine research aimed at inducing bNAbs. We therefore performed a direct and thorough comparison of a full-length native Env trimer containing the transmembrane domain and the cytoplasmic tail, with the sequence matched soluble SOSIP trimer, both based on an early Env sequence (AMC011) from an HIV+ individual that developed bNAbs. The structures of the full-length AMC011 trimer bound to either bNAb PGT145 or PGT151 were very similar to the structures of SOSIP trimers. Antigenically, the full-length and SOSIP trimers were comparable, but in contrast to the full-length trimer, the SOSIP trimer did not bind at all to non-neutralizing antibodies, most likely as a consequence of the intrinsic stabilization of the SOSIP trimer. Furthermore, the glycan composition of full-length and SOSIP trimers was similar overall, but the SOSIP trimer possessed slightly less complex and less extensively processed glycans, which may relate to the intrinsic stabilization as well as the absence of the membrane tether. These data provide insights into how to best use and improve membrane-associated full-length and soluble SOSIP HIV-1 Env trimers as immunogens.


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