scholarly journals Immunogenicity, safety, and efficacy of sequential immunizations with an SIV-based IDLV expressing CH505 Envs

npj Vaccines ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Maria Blasi ◽  
Donatella Negri ◽  
Kevin O. Saunders ◽  
Erich J. Baker ◽  
Hannah Stadtler ◽  
...  
Keyword(s):  
Immune Responses ◽  
Neutralizing Antibodies ◽  
Lentiviral Vector ◽  
Rhesus Macaques ◽  
Infected Individual ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Safety And Efficacy ◽  
Env Protein ◽  
Hiv 1

AbstractA preventative HIV-1 vaccine is an essential intervention needed to halt the HIV-1 pandemic. Neutralizing antibodies protect against HIV-1 infection in animal models, and thus an approach toward a protective HIV-1 vaccine is to induce broadly cross-reactive neutralizing antibodies (bnAbs). One strategy to achieve this goal is to define envelope (Env) evolution that drives bnAb development in infection and to recreate those events by vaccination. In this study, we report the immunogenicity, safety, and efficacy in rhesus macaques of an SIV-based integrase defective lentiviral vector (IDLV) expressing sequential gp140 Env immunogens derived from the CH505 HIV-1-infected individual who made the CH103 and CH235 bnAb lineages. Immunization with IDLV expressing sequential CH505 Envs induced higher magnitude and more durable binding and neutralizing antibody responses compared to protein or DNA +/− protein immunizations using the same sequential envelopes. Compared to monkeys immunized with a vector expressing Envs alone, those immunized with the combination of IDLV expressing Env and CH505 Env protein demonstrated improved durability of antibody responses at six months after the last immunization as well as lower peak viremia and better virus control following autologous SHIV-CH505 challenge. There was no evidence of vector mobilization or recombination in the immunized and challenged monkeys. Although the tested vaccines failed to induce bnAbs and to mediate significant protection following SHIV-challenge, our results show that IDLV proved safe and successful at inducing higher titer and more durable immune responses compared to other vaccine platforms.

scholarly journals Immunogenicity, safety and efficacy of sequential immunizations with an SIV-based IDLV expressing CH505 Envs

2020 ◽  
Author(s):  
Blasi Maria ◽  
Negri Donatella ◽  
Saunders O Kevin ◽  
Baker J Erich ◽  
Stadtler Hannah ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Lentiviral Vector ◽  
Rhesus Macaques ◽  
Infected Individual ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Safety And Efficacy ◽  
Broadly Neutralizing Antibody ◽  
Env Protein ◽  
Hiv 1

AbstractA preventative HIV-1 vaccine is an essential intervention needed to halt the HIV-1 pandemic. Neutralizing antibodies protect against HIV-1 infection in animal models, and thus an approach toward a protective HIV-1 vaccine is to induce broadly cross-reactive neutralizing antibodies (bnAbs). One strategy to achieve this goal is to define envelope (Env) evolution that drives bnAb development in infection and to recreate those events by vaccination. In this study we report the immunogenicity, safety and efficacy in rhesus macaques of an SIV-based integrase defective lentiviral vector (IDLV) expressing sequential gp140 Env immunogens derived from the CH505 HIV-1-infected individual who made the CH103 and CH235 bnAb lineages. Immunization with IDLV expressing sequential CH505 Env induced higher magnitude and more durable binding and neutralizing antibody responses compared to protein or DNA +/- protein immunizations using the same sequential envelopes. Compared to monkeys immunized with vector expressing Envs alone, those immunized with the combination of IDLV expressing Env and CH505 Env protein demonstrated improved durability of antibody responses at six month after the last immunization as well as lower peak viremia and better virus control following autologous SHIV-CH505 challenge. There was no evidence of vector mobilization or recombination in the immunized and challenged monkeys. Our results show that while IDLV proved safe and successful at inducing higher titer and more durable immune responses compared to other vaccine platforms, the use of non-stabilized sequential envelope trimers did not induce broadly neutralizing antibody responses.

scholarly journals Elicitation of potent serum neutralizing antibody responses in rabbits by immunization with an HIV-1 clade C trimeric Env derived from an Indian elite neutralizer

2020 ◽  
Author(s):  
Rajesh Kumar ◽  
Suprit Deshpande ◽  
Leigh M. Sewall ◽  
Gabriel Ozorowski ◽  
Christopher A. Cottrell ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Neutralizing Antibodies ◽  
Natural Infection ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Clade C ◽  
Immunogen Design ◽  
Env Protein ◽  
Immunogenic Properties ◽  
Hiv 1

AbstractEvaluating the structure-function relationship of viral envelope (Env) evolution and the development of broadly cross-neutralizing antibodies (bnAbs) in natural infection can inform rational immunogen design. In the present study, we examined the magnitude and specificity of autologous neutralizing antibodies induced in rabbits by a novel HIV-1 clade C Env protein (1PGE-THIVC) vis-à-vis those developed in an elite neutralizer from whom the env sequence was obtained that was used to prepare the soluble Env protein. The thermostable 1PGE-THIVC Env displayed a native like pre-fusion closed conformation in solution as determined by small angle X-ray scattering (SAXS) and negative stain electron microscopy (EM). This closed spike conformation of 1PGE-THIVC Env trimers was correlated with weak or undetectable binding of non-neutralizing monoclonal antibodies (mAbs) compared to neutralizing mAbs. Furthermore, 1PGE-THIVC SOSIP induced potent neutralizing antibodies in rabbits to autologous virus variants. The autologous neutralizing antibody specificity induced in rabbits by 1PGE-THIVC was mapped to the C3/V4 region (T362/P401) of viral Env. This observation agreed with electron microscopy polyclonal epitope mapping (EMPEM) of the Env trimer complexed with IgG Fab prepared from the immunized rabbit sera. While the specificity of antibodies elicited in rabbits associated with neutralizing autologous viruses were distinct to those developed in the elite neutralizer, EMPEM analysis demonstrated significant changes to Env conformations when incubated with polyclonal antibody sera from the elite neutralizer, suggesting these antibodies lead to the destabilization of Env trimers. Our study not only shows distinct mechanisms associated with potent neutralization of sequence matched and unmatched autologous viruses by antibodies induced in rabbits and in the elite neutralizer, but also highlights how neutralizing antibodies developed during the course of natural infection can impact viral Env conformations.Author SummaryThe interplay between circulating virus variants and broadly cross neutralizing polyclonal antibodies developed in a subset of elite neutralizers is widely believed to provide strategies for rational immunogen design. In the present study, we studied the structural, antigenic and immunogenic properties of a thermostable soluble trimeric protein with near native pre-fusion conformation prepared using the primary sequence of an HIV-1 clade C env isolated from the broadly cross neutralizing plasma of an elite neutralizer. This novel SOSIP Env trimer demonstrated comparable antigenic, structural and immunogenic properties that favoured several ongoing subunit vaccine design efforts. The novel clade C SOSIP induced polyclonal neutralizing antibody response developed in rabbits not only differed in its epitope specificity compared to that elicited in natural infection in presence of pool of viral quasispecies but also showed how they differ in their ability to influence Env structure and conformation. A better understanding of how vaccine-induced polyclonal neutralizing antibody responses compares to responses that developed in natural infection will improve our knowledge in designing better vaccine design strategies.

scholarly journals Biochemical and Immunogenic Characterization of Soluble Human Immunodeficiency Virus Type 1 Envelope Glycoprotein Trimers Expressed by Semliki Forest Virus

2005 ◽  
Vol 79 (17) ◽  
pp. 10902-10914 ◽  
Author(s):  
Mattias N. E. Forsell ◽  
Yuxing Li ◽  
Maria Sundbäck ◽  
Krisha Svehla ◽  
Peter Liljeström ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Immune Responses ◽  
Envelope Glycoprotein ◽  
Neutralizing Antibodies ◽  
Semliki Forest Virus ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The current lack of envelope glycoprotein immunogens that elicit broadly neutralizing antibody responses remains a major challenge for human immunodeficiency virus type 1 (HIV-1) vaccine development. However, the recent design and construction of stable soluble gp140 trimers have shown that some neutralization breadth can be achieved by using immunogens that better mimic the functional viral spike complex. The use of genetic delivery systems to drive the in vivo expression of such immunogens for the stimulation of neutralizing antibodies against HIV-1 may offer advantages by maintaining the quaternary structure of the trimeric envelope glycoproteins. Here, we describe the biochemical and immunogenic properties of soluble HIV-1 envelope glycoprotein trimers expressed by recombinant Semliki Forest virus (rSFV). The results presented here demonstrate that rSFV supports the expression of stable soluble gp140 trimers that retain recognition by conformationally sensitive antibodies. Further, we show that rSFV particle immunizations efficiently primed immune responses as measured after a single boost with purified trimeric gp140 protein, resulting in a Th1-biased antibody response. This differed from the Th2-biased antibody response obtained after repeated immunizations with purified gp140 protein trimers. Despite this difference, both regimens stimulated neutralizing antibody responses of similar potency. This suggests that rSFV may be a useful component of a viral vector prime-protein boost regimen aimed at stimulating both cell-mediated immune responses and neutralizing antibodies against HIV-1.

scholarly journals Antibody Responses Elicited in Macaques Immunized with Human Immunodeficiency Virus Type 1 (HIV-1) SF162-Derived gp140 Envelope Immunogens: Comparison with Those Elicited during Homologous Simian/Human Immunodeficiency Virus SHIVSF162P4 and Heterologous HIV-1 Infection

2006 ◽  
Vol 80 (17) ◽  
pp. 8745-8762 ◽  
Author(s):  
Nina R. Derby ◽  
Zane Kraft ◽  
Elaine Kan ◽  
Emma T. Crooks ◽  
Susan W. Barnett ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Neutralizing Antibodies ◽  
Rhesus Macaques ◽  
Hypervariable Region ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
V3 Loop ◽  
Immunodeficiency Virus ◽  
The Difference ◽  
Hiv 1

ABSTRACT The antibody responses elicited in rhesus macaques immunized with soluble human immunodeficiency virus (HIV) Env gp140 proteins derived from the R5-tropic HIV-1 SF162 virus were analyzed and compared to the broadly reactive neutralizing antibody responses elicited during chronic infection of a macaque with a simian/human immunodeficiency virus (SHIV) expressing the HIV-1 SF162 Env, SHIVSF162P4, and humans infected with heterologous HIV-1 isolates. Four gp140 immunogens were evaluated: SF162gp140, ΔV2gp140 (lacking the crown of the V2 loop), ΔV3gp140 (lacking the crown of the V3 loop), and ΔV2ΔV3gp140 (lacking both the V2 and V3 loop crowns). SF162gp140 and ΔV2gp140 have been previously evaluated by our group in a pilot study, but here, a more comprehensive analysis of their immunogenic properties was performed. All four gp140 immunogens elicited stronger anti-gp120 than anti-gp41 antibodies and potent homologous neutralizing antibodies (NAbs) that primarily targeted the first hypervariable region (V1 loop) of gp120, although SF162gp140 also elicited anti-V3 NAbs. Heterologous NAbs were elicited by SF162gp140 and ΔV2gp140 but were weak in potency and narrow in specificity. No heterologous NAbs were elicited by ΔV3gp140 or ΔV2ΔV3gp140. In contrast, the SHIVSF162P4-infected macaque and HIV-infected humans generated similar titers of anti-gp120 and anti-gp41 antibodies and NAbs of significant breadth against primary HIV-1 isolates, which did not target the V1 loop. The difference in V1 loop immunogenicity between soluble gp140 and virion-associated gp160 Env proteins derived from SF162 may be the basis for the observed difference in the breadth of neutralization in sera from the immunized and infected animals studied here.

scholarly journals Comparison of Immunogenicity in Rhesus Macaques of Transmitted-Founder, HIV-1 Group M Consensus, and Trivalent Mosaic Envelope Vaccines Formulated as a DNA Prime, NYVAC, and Envelope Protein Boost

2015 ◽  
Vol 89 (12) ◽  
pp. 6462-6480 ◽  
Author(s):  
Sandrine L. Hulot ◽  
Bette Korber ◽  
Elena E. Giorgi ◽  
Nathan Vandergrift ◽  
Kevin O. Saunders ◽  
...  
Keyword(s):  
T Cell ◽  
In Silico ◽  
Neutralizing Antibodies ◽  
Rhesus Macaques ◽  
Antibody Responses ◽  
T Cell Epitopes ◽  
Cell Responses ◽  
Protein Boost ◽  
Env Protein ◽  
Hiv 1

ABSTRACTAn effective human immunodeficiency virus type 1 (HIV-1) vaccine must induce protective antibody responses, as well as CD4+and CD8+T cell responses, that can be effective despite extraordinary diversity of HIV-1. The consensus and mosaic immunogens are complete but artificial proteins, computationally designed to elicit immune responses with improved cross-reactive breadth, to attempt to overcome the challenge of global HIV diversity. In this study, we have compared the immunogenicity of a transmitted-founder (T/F) B clade Env (B.1059), a global group M consensus Env (Con-S), and a global trivalent mosaic Env protein in rhesus macaques. These antigens were delivered using a DNA prime-recombinant NYVAC (rNYVAC) vector and Env protein boost vaccination strategy. While Con-S Env was a single sequence, mosaic immunogens were a set of three Envs optimized to include the most common forms of potential T cell epitopes. Both Con-S and mosaic sequences retained common amino acids encompassed by both antibody and T cell epitopes and were central to globally circulating strains. Mosaics and Con-S Envs expressed as full-length proteins bound well to a number of neutralizing antibodies with discontinuous epitopes. Also, both consensus and mosaic immunogens induced significantly higher gamma interferon (IFN-γ) enzyme-linked immunosorbent spot assay (ELISpot) responses than B.1059 immunogen. Immunization with these proteins, particularly Con-S, also induced significantly higher neutralizing antibodies to viruses than B.1059 Env, primarily to tier 1 viruses. Both Con-S and mosaics stimulated more potent CD8-T cell responses against heterologous Envs than did B.1059. Both antibody and cellular data from this study strengthen the concept of usingin silico-designed centralized immunogens for global HIV-1 vaccine development strategies.IMPORTANCEThere is an increasing appreciation for the importance of vaccine-induced anti-Env antibody responses for preventing HIV-1 acquisition. This nonhuman primate study demonstrates thatin silico-designed global HIV-1 immunogens, designed for a human clinical trial, are capable of eliciting not only T lymphocyte responses but also potent anti-Env antibody responses.

scholarly journals Characterization and Implementation of a Diverse Simian Immunodeficiency Virus SIVsm Envelope Panel in the Assessment of Neutralizing Antibody Breadth Elicited in Rhesus Macaques by Multimodal Vaccines Expressing the SIVmac239 Envelope

2015 ◽  
Vol 89 (16) ◽  
pp. 8130-8151 ◽  
Author(s):  
Katie M. Kilgore ◽  
Megan K. Murphy ◽  
Samantha L. Burton ◽  
Katherine S. Wetzel ◽  
S. Abigail Smith ◽  
...  
Keyword(s):  
Simian Immunodeficiency Virus ◽  
Nonhuman Primate ◽  
Neutralizing Antibodies ◽  
Rhesus Macaques ◽  
Neutralizing Antibody ◽  
Cd40 Ligand ◽  
Antibody Activity ◽  
Immunodeficiency Virus ◽  
Antibody Profile ◽  
Hiv 1

ABSTRACTAntibodies that can neutralize diverse viral strains are likely to be an important component of a protective human immunodeficiency virus type 1 (HIV-1) vaccine. To this end, preclinical simian immunodeficiency virus (SIV)-based nonhuman primate immunization regimens have been designed to evaluate and enhance antibody-mediated protection. However, these trials often rely on a limited selection of SIV strains with extreme neutralization phenotypes to assess vaccine-elicited antibody activity. To mirror the viral panels used to assess HIV-1 antibody breadth, we created and characterized a novel panel of 14 genetically and phenotypically diverse SIVsm envelope (Env) glycoproteins. To assess the utility of this panel, we characterized the neutralizing activity elicited by four SIVmac239 envelope-expressing DNA/modified vaccinia virus Ankara vector- and protein-based vaccination regimens that included the immunomodulatory adjuvants granulocyte-macrophage colony-stimulating factor, Toll-like receptor (TLR) ligands, and CD40 ligand. The SIVsm Env panel exhibited a spectrum of neutralization sensitivity to SIV-infected plasma pools and monoclonal antibodies, allowing categorization into three tiers. Pooled sera from 91 rhesus macaques immunized in the four trials consistently neutralized only the highly sensitive tier 1a SIVsm Envs, regardless of the immunization regimen. The inability of vaccine-mediated antibodies to neutralize the moderately resistant tier 1b and tier 2 SIVsm Envs defined here suggests that those antibodies were directed toward epitopes that are not accessible on most SIVsm Envs. To achieve a broader and more effective neutralization profile in preclinical vaccine studies that is relevant to known features of HIV-1 neutralization, more emphasis should be placed on optimizing the Env immunogen, as the neutralization profile achieved by the addition of adjuvants does not appear to supersede the neutralizing antibody profile determined by the immunogen.IMPORTANCEMany in the HIV/AIDS vaccine field believe that the ability to elicit broadly neutralizing antibodies capable of blocking genetically diverse HIV-1 variants is a critical component of a protective vaccine. Various SIV-based nonhuman primate vaccine studies have investigated ways to improve antibody-mediated protection against a heterologous SIV challenge, including administering adjuvants that might stimulate a greater neutralization breadth. Using a novel SIV neutralization panel and samples from four rhesus macaque vaccine trials designed for cross comparison, we show that different regimens expressing the same SIV envelope immunogen consistently elicit antibodies that neutralize only the very sensitive tier 1a SIV variants. The results argue that the neutralizing antibody profile elicited by a vaccine is primarily determined by the envelope immunogen and is not substantially broadened by including adjuvants, resulting in the conclusion that the envelope immunogen itself should be the primary consideration in efforts to elicit antibodies with greater neutralization breadth.

scholarly journals Neutralizing Antibody Responses in Acute Human Immunodeficiency Virus Type 1 Subtype C Infection

2007 ◽  
Vol 81 (12) ◽  
pp. 6187-6196 ◽  
Author(s):  
E. S. Gray ◽  
P. L. Moore ◽  
I. A. Choge ◽  
J. M. Decker ◽  
F. Bibollet-Ruche ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Subtype C ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The study of the evolution and specificities of neutralizing antibodies during the course of human immunodeficiency virus type 1 (HIV-1) infection may be important in the discovery of possible targets for vaccine design. In this study, we assessed the autologous and heterologous neutralization responses of 14 HIV-1 subtype C-infected individuals, using envelope clones obtained within the first 2 months postinfection. Our data show that potent but relatively strain-specific neutralizing antibodies develop within 3 to 12 months of HIV-1 infection. The magnitude of this response was associated with shorter V1-to-V5 envelope lengths and fewer glycosylation sites, particularly in the V1-V2 region. Anti-MPER antibodies were detected in 4 of 14 individuals within a year of infection, while antibodies to CD4-induced (CD4i) epitopes developed to high titers in 12 participants, in most cases before the development of autologous neutralizing antibodies. However, neither anti-MPER nor anti-CD4i antibody specificity conferred neutralization breadth. These data provide insights into the kinetics, potency, breadth, and epitope specificity of neutralizing antibody responses in acute HIV-1 subtype C infection.

scholarly journals Nanoparticle Vaccines for Inducing HIV-1 Neutralizing Antibodies

Vaccines ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 76 ◽  
Author(s):  
Mitch Brinkkemper ◽  
Kwinten Sliepen
Keyword(s):  
Envelope Glycoprotein ◽  
Neutralizing Antibodies ◽  
Critical Role ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Broadly Neutralizing Antibodies ◽  
Viral Membrane ◽  
Immunodeficiency Virus ◽  
Hiv 1

The enormous sequence diversity between human immunodeficiency virus type 1 (HIV-1) strains poses a major roadblock for generating a broadly protective vaccine. Many experimental HIV-1 vaccine efforts are therefore aimed at eliciting broadly neutralizing antibodies (bNAbs) that are capable of neutralizing the majority of circulating HIV-1 strains. The envelope glycoprotein (Env) trimer on the viral membrane is the sole target of bNAbs and the key component of vaccination approaches aimed at eliciting bNAbs. Multimeric presentation of Env on nanoparticles often plays a critical role in these strategies. Here, we will discuss the different aspects of nanoparticles in Env vaccination, including recent insights in immunological processes underlying their perceived advantages, the different nanoparticle platforms and the various immunogenicity studies that employed nanoparticles to improve (neutralizing) antibody responses against Env.

scholarly journals Effect of HIV Envelope Vaccination on the Subsequent Antibody Response to HIV Infection

mSphere ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Zanele Ditse ◽  
Nonhlanhla N. Mkhize ◽  
Michael Yin ◽  
Michael Keefer ◽  
David C. Montefiori ◽  
...  
Keyword(s):  
Immune Responses ◽  
Hiv Infection ◽  
South African ◽  
Phase 1 ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Tier 2 ◽  
Subtype C ◽  
Hiv Envelope ◽  
Hiv 1

ABSTRACT Analysis of breakthrough HIV-1 infections could elucidate whether prior vaccination primes relevant immune responses. Here, we measured HIV-specific antibody responses in 14 South African volunteers who acquired HIV infection after participating in phase 1/2 trials of envelope-containing immunogens. Serum samples were collected annually following HIV-1 infection from participants in trials HVTN 073 (subtype C, DNA/MVA, phase 1 trial, n = 1), HVTN 086 (subtype C, DNA/MVA/gp140 protein, phase 1 trial, n = 2), and HVTN 204 (multisubtype, DNA/adenovirus serotype 5 [Ad5], phase 2 trial, n = 7) and 4 placebo recipients. Binding and neutralizing antibody responses to Env proteins and peptides were determined pre- and post-HIV infection using an enzyme-linked immunosorbent assay and the TZM-bl cell neutralization assay, respectively. HIV-infected South African individuals served as unvaccinated controls. Binding antibodies to gp41, V3, V2, the membrane-proximal external region (MPER), and the CD4 binding site were detected from the first year of HIV-1 subtype C infection, and the levels were similar in vaccinated and placebo recipients. Neutralizing antibody responses against tier 1A viruses were detected in all participants, with the highest titers being to a subtype C virus, MW965.26. No responses were observed just prior to infection, indicating that vaccine-primed HIV-specific antibodies had waned. Sporadic neutralization activity against tier 2 isolates was observed after 2 to 3 years of HIV infection, but these responses were similar in the vaccinated and placebo groups as well as the unvaccinated controls. Our data suggest that prior vaccination with these immunogens did not alter the antibody responses to HIV-1 infection, nor did it accelerate the development of HIV neutralization breadth. IMPORTANCE There is a wealth of information on HIV-specific vaccine-induced immune responses among HIV-uninfected participants; however, data on immune responses among participants who acquire HIV after vaccination are limited. Here we show that HIV-specific binding antibody responses in individuals with breakthrough HIV infections were not affected by prior vaccination with HIV envelope-containing immunogens. We also found that these vectored vaccines did not prime tier 2 virus-neutralizing antibody responses, which are thought to be required for prevention against HIV acquisition, or accelerate the development of neutralization breadth. Although this study is limited, such studies can provide insights into whether vaccine-elicited antibody responses are boosted by HIV infection to acquire broader neutralizing activity, which may help to identify antigens relevant to the design of more effective vaccines.

scholarly journals Rectal Microbiome Composition Correlates with Humoral Immunity to HIV-1 in Vaccinated Rhesus Macaques

mSphere ◽  
2019 ◽  
Vol 4 (6) ◽  
Author(s):  
Sonny R. Elizaldi ◽  
Anil Verma ◽  
Korey A. Walter ◽  
Matthew Rolston ◽  
Ashok R. Dinasarapu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Rhesus Macaques ◽  
Temporal Stability ◽  
Hiv Vaccine ◽  
Antibody Responses ◽  
Critical Determinant ◽  
Dynamic Component ◽  
Microbiome Composition ◽  
Vaccine Immunogenicity ◽  
Hiv 1

ABSTRACT The microbiome is an integral and dynamic component of the host and is emerging as a critical determinant of immune responses; however, its influence on vaccine immunogenicity is largely not well understood. Here, we examined the pivotal relationship between the mucosal microbiome and vaccine-induced immune responses by assessing longitudinal changes in vaginal and rectal microbiome profiles after intradermal immunization with a human immunodeficiency virus type 1 (HIV-1) DNA vaccine in adult rhesus macaques that received two prior DNA primes. We report that both vaginal and rectal microbiomes were dominated by Firmicutes but were composed of distinct genera, denoting microbiome specialization across mucosal tissues. Following immunization, the vaginal microbiome was resilient, except for a transient decrease in Streptococcus. In contrast, the rectal microbiome was far more responsive to vaccination, exhibiting an increase in the ratio of Firmicutes to Bacteroidetes. Within Bacteroidetes, multiple genera were significantly decreased, including Prevotella, Alloprevotella, Bacteroides, Acetobacteroides, Falsiporphyromonas, and Anaerocella. Decreased abundance of Prevotella correlated with induction of gut-homing α4β7+ effector CD4 T cells. Prevotella abundance also negatively correlated with rectal HIV-1 specific IgG levels. While rectal Lactobacillus was unaltered following DNA vaccination, baseline Lactobacillus abundance showed strong associations with higher rectal HIV-1 gp140 IgA induced following a protein boost. Similarly, the abundance of Clostridium in cluster IV was associated with higher rectal HIV-1 gp140 IgG responses. Collectively, these data reveal that the temporal stability of bacterial communities following DNA immunization is site dependent and highlight the importance of host-microbiome interactions in shaping HIV-1 vaccine responses. Our findings have significant implications for microbial manipulation as a strategy to enhance HIV vaccine-induced mucosal immunity. IMPORTANCE There is considerable effort directed toward evaluating HIV-1 vaccine platforms to select the most promising candidates for enhancing mucosal HIV-1 antibody. The most successful thus far, the RV144 trial provided partial protection due to waning HIV-1 antibody titers. In order to develop an effective HIV vaccine, it may therefore be important to understand how biological factors, such as the microbiome, modulate host immune responses. Furthermore, as intestinal microbiota antigens may generate antibodies cross-reactive to the HIV-1 envelope glycoprotein, understanding the relationship between gut microbiota composition and HIV-1 envelope antibody responses after vaccination is important. Here, we demonstrate for the first time in rhesus macaques that the rectal microbiome composition can influence HIV-1 vaccine immunogenicity, and we report temporal changes in the mucosal microbiome profile following HIV-1 vaccination. Our results could inform findings from the HIV Vaccine Trials Network (HVTN) vaccine studies and contribute to an understanding of how the microbiome influences HIV-1 antibody responses.

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