Dataset Information

Photoinduced Photosensitizer-Antibody Conjugates Kill HIV Env-Expressing Cells, Also Inactivating HIV.

ABSTRACT: HIV-infected cells persist for decades in patients administered with antiretroviral therapy (ART). Meanwhile, an alarming surge in drug-resistant HIV viruses has been occurring. Addressing these issues, we propose the application of photoimmunotherapy (PIT) against not only HIV Env-expressing cells but also HIV. Previously, we showed that a human anti-gp41 antibody (7B2) conjugated to cationic or anionic photosensitizers (PSs) could specifically target and kill the HIV Env-expressing cells. Here, our photolysis studies revealed that the binding of photoimmunoconjugates (PICs) on the membrane of HIV Env-expressing cells is sufficient to induce necrotic cell death due to physical damage to the membrane by singlet oxygen, which is independent of the type of PSs. This finding persuaded us to study the virus photoinactivation of PICs using two HIV-1 strains, X4 HIV-1 NL4-3 and JR-CSF virus. We observed that the PICs could destroy the viral strains, probably via physical damage on the HIV envelope. In conclusion, we report the application of PIT as a possible dual-tool for HIV immunotherapy and ART by killing HIV-expressing cells and cell-free HIV, respectively.

SUBMITTER: Sadraeian M

PROVIDER: S-EPMC8246456 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Photoinduced Photosensitizer-Antibody Conjugates Kill HIV Env-Expressing Cells, Also Inactivating HIV.

Sadraeian Mohammad M da Cruz Edgar Ferreira EF Boyle Ross W RW Bahou Calise C Chudasama Vijay V Janini Luiz Mário Ramos LMR Diaz Ricardo Sobhie RS Guimarães Francisco E G FEG

ACS omega 20210608 25

HIV-infected cells persist for decades in patients administered with antiretroviral therapy (ART). Meanwhile, an alarming surge in drug-resistant HIV viruses has been occurring. Addressing these issues, we propose the application of photoimmunotherapy (PIT) against not only HIV Env-expressing cells but also HIV. Previously, we showed that a human anti-gp41 antibody (7B2) conjugated to cationic or anionic photosensitizers (PSs) could specifically target and kill the HIV Env-expressing cells. Here ...[more]

PMID: 34235324

Similar Datasets

Project description:A strategy has been established for the synthesis of a family of bifunctional HIV-1 inhibitor covalent conjugates with the potential to bind simultaneously to both the gp120 and gp41 subunits of the HIV-1 envelope glycoprotein trimeric complex (Env). One component of the conjugates is derived from BNM-III-170, a small-molecule CD4 mimic that binds to gp120. The second component, comprised of the peptide DKWASLWNW ("Trp3"), was derived from the N-terminus of the HIV-1 gp41 Membrane Proximal External Region (MPER) and found previously to bind to the gp41 subunit of Env. The resulting bifunctional conjugates were shown to inhibit virus cell infection with low micromolar potency and to induce lysis of the HIV-1 virion. Crucially, virolysis was found to be dependent on the covalent linkage of the BNM-III-170 and Trp3 domains, as coadministration of a mixture of the un-cross-linked components proved to be nonlytic. However, a significant magnitude of lytic activity was observed in Env-negative and other control pseudoviruses, suggesting parallel mechanisms of action of the conjugates involving Env interaction and direct membrane disruption. Computational modeling suggested strong membrane-binding activity of BNM-III-170, which may underly the nonspecific virolytic effects of the conjugates. To investigate the scope of the membrane effect, cell-based cytotoxicity and membrane permeability assays were performed employing flow cytometry. Here, we observed a dose-dependent and specific cytotoxic effect on HIV-1 Env-expressing cells by the small-molecule bifunctional inhibitor. Most importantly, Env-negative cells were not susceptible to the cytotoxic effect upon exposure to this construct at concentrations where cell-killing effects were observed for Env-positive cells. Computational structural modeling supports a mechanism in which the bifunctional inhibitors bind to the gp120 and gp41 subunits in tandem in open-state Env trimers and induce relative motion of the gp120 subunits consistent with models of Env inactivation. This observation supports the idea that the cell-killing effect of the small-molecule bifunctional inhibitor is due to specific Env conformational triggering. This work lays important groundwork to advance a small-molecule bifunctional inhibitor approach for eliminating Env-expressing infected cells and the eradication of HIV-1.

Project description:Rationale: Antiretroviral therapy can effectively suppress HIV-1 replication in the peripheral blood to an undetectable level. However, elimination of the latent virus in reservoirs remains a challenge and is a major obstacle in the treatment of HIV-1-infected patients. Exosomes exhibit huge promise as an endogenous drug delivery nanosystem for delivering drugs to solid tissues given their unique properties, including low immunogenicity, innate stability, high delivery efficiency, and most importantly the ability to penetrate solid tissues due to their lipophilic properties. Methods: We engineered and expressed the scFv of a high affinity HIV-1-specific monoclonal antibody, 10E8, on the exosomal surface (10E8scFv-exos). Subsequently, the 10E8scFv-exos were loaded with curcumin (Cur), a chemical that kills HIV-1-infected cells, or miR-143, an apoptosis-inducing miRNA. We tested the ability of 10E8scFv-exos to deliver cargo to Env+ target cells and tissues, as well as their ability to suppress HIV-1 infection. Results: 10E8scFv-exos efficiently targeted CHO cells expressing a trimeric gp140 on their surface (Env+ cells) in vitro, as demonstrated by confocal imaging and flow cytometry. 10E8scFv-exos loaded with Cur or miR-143 showed specific killing of Env+ cells. In addition, 10E8scFv-exos loaded with Cur or miR-143 could suppress p24 expression in an HIV-1 latency cell line ACH2 and in PBMCs from an ART-treated HIV-1-infected patient. In an NCG mouse model grafted with tumorigenic Env+ CHO cells and which had developed solid tissue tumors, intravenously injected 10E8scFv-exos targeted the Env-expressing tissues and delivered Cur to induce a strong suppression of the Env+ tumor growth with low toxicity. Conclusion: In principle, engineered exosomes can deliver anti-HIV agents to solid tissues by specifically targeting cells expressing viral envelop proteins and inducing cell killing, suggesting that such an approach could be developed for eradicating virus-infected cells in tissue reservoirs.

Project description:Human immunodeficiency virus type 1 (HIV-1) envelope (Env), a heterotrimer of gp120-gp41 subunits, mediates fusion of the viral and host cell membranes after interactions with the host receptor CD4 and a coreceptor. CD4 binding induces rearrangements in Env trimer, resulting in a CD4-induced (CD4i) open Env conformation. Structural studies of antibodies isolated from infected donors have defined antibody-Env interactions, with one class of antibodies specifically recognizing the CD4i open Env conformation. In this study, we characterized a group of monoclonal antibodies isolated from HIV-1 infected donors (V2i MAbs) that displayed characteristics of CD4i antibodies. Binding experiments demonstrated that the V2i MAbs preferentially recognize CD4-bound open Env trimers. Structural characterizations of V2i MAb-Env-CD4 trimer complexes using single-particle cryo-electron microscopy showed recognition by V2i MAbs using different angles of approach to the gp120 V1V2 domain and the β2/β3 strands on a CD4i open conformation Env with no direct interactions of the MAbs with CD4. We also characterized CG10, a CD4i antibody that was raised in mice immunized with a gp120-CD4 complex, bound to an Env trimer plus CD4. CG10 exhibited characteristics similar to those of the V2i antibodies, i.e., recognition of the open Env conformation, but showed direct contacts to both CD4 and gp120. Structural comparisons of these and previously characterized CD4i antibody interactions with Env provide a suggested mechanism for how these antibodies are elicited during HIV-1 infection. IMPORTANCE The RV144 HIV-1 clinical vaccination trial showed modest protection against viral infection. Antibody responses to the V1V2 region of HIV-1 Env gp120 were correlated inversely with the risk of infection, and data from three other clinical vaccine trials suggested a similar signal. In addition, antibodies targeting V1V2 have been correlated with protections from simian immunodeficiency virus (SIV) and simian-human immunodeficiency virus (SHIV) infections in nonhuman primates. We structurally characterized V2i antibodies directed against V1V2 isolated from HIV-1 infected humans in complex with open Env trimers bound to the host receptor CD4. We also characterized a CD4i antibody that interacts with CD4 as well as the gp120 subunit of an open Env trimer. Our study suggests how V2i and CD4i antibodies were elicited during HIV-1 infection.

Dataset Information

Photoinduced Photosensitizer-Antibody Conjugates Kill HIV Env-Expressing Cells, Also Inactivating HIV.

Publications

Photoinduced Photosensitizer-Antibody Conjugates Kill HIV Env-Expressing Cells, Also Inactivating HIV.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets