RESUMEN
Single agent immune checkpoint inhibitors have been ineffective for patients with advanced stage and recurrent high grade serous ovarian cancer (HGSOC). Using pre-clinical models of HGSOC, we evaluated the anti-tumor and immune stimulatory effects of an oncolytic adenovirus, MEM-288. This conditionally replicative virus encodes a modified membrane stable CD40L and IFNß. We demonstrated this virus successfully infects HGSOC cell lines and primary human ascites samples in vitro. We evaluated the anti-tumor and immunostimulatory activity in vivo in immune competent mouse models. Intraperitoneal delivery of MEM-288 decreased ascites and solid tumor burden compared to controls, and treatment generated a systemic anti-tumor immune response. The tumor microenvironment had a higher proportion of anti-tumor macrophages and decreased markers of angiogenesis. MEM-288 is a promising immunotherapy agent in HGSOC, with further pre-clinical studies required to understand the mechanism of action in the peritoneal microenvironment and clinical activity in combination with other therapies.
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Adenoviridae , Ligando de CD40 , Cistadenocarcinoma Seroso , Interferón beta , Viroterapia Oncolítica , Virus Oncolíticos , Neoplasias Ováricas , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Femenino , Humanos , Animales , Neoplasias Ováricas/terapia , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/patología , Neoplasias Ováricas/genética , Ratones , Adenoviridae/genética , Virus Oncolíticos/genética , Virus Oncolíticos/inmunología , Interferón beta/genética , Interferón beta/metabolismo , Viroterapia Oncolítica/métodos , Microambiente Tumoral/inmunología , Ligando de CD40/genética , Ligando de CD40/metabolismo , Línea Celular Tumoral , Cistadenocarcinoma Seroso/terapia , Cistadenocarcinoma Seroso/inmunología , Cistadenocarcinoma Seroso/patología , Cistadenocarcinoma Seroso/genética , Vectores Genéticos/genética , Vectores Genéticos/administración & dosificación , Modelos Animales de Enfermedad , Clasificación del Tumor , Inmunoterapia/métodosRESUMEN
Immunoglobulin A (IgA) is the predominant mucosal antibody class with both anti- and pro-inflammatory roles1-3. However, the specific role of the IgA receptor cluster of differentiation (CD)89, expressed by a subset of natural killer (NK) cells, is poorly explored. We found that CD89 protein expression on circulating NK cells is infrequent in humans and rhesus macaques, but transcriptomic analysis showed ubiquitous CD89 expression, suggesting an inducible phenotype. Interestingly, CD89+ NK cells were more frequent in cord blood and mucosae, indicating a putative IgA-mediated NK cell function in the mucosae and infant immune system. CD89+ NK cells signaled through upregulated CD3 zeta chain (CD3ζ), spleen tyrosine kinase (Syk), zeta chain-associated protein kinase 70 (ZAP70), and signaling lymphocytic activation molecule family 1 (SLAMF1), but also showed high expression of inhibitory receptors such as killer cell lectin-like receptor subfamily G (KLRG1) and reduced activating NKp46 and NKp30. CD89-based activation or antibody-mediated cellular cytotoxicity with monomeric IgA1 reduced NK cell functions, while antibody-mediated cellular cytotoxicity with combinations of IgG and IgA2 was enhanced compared to IgG alone. These data suggest that functional CD89+ NK cells survey mucosal sites, but CD89 likely serves as regulatory receptor which can be further modulated depending on IgA and IgG subclass. Although the full functional niche of CD89+ NK cells remains unexplored, these intriguing data suggest the CD89 axis could represent a novel immunotherapeutic target in the mucosae or early life.
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Inmunoglobulina A , Células Asesinas Naturales , Macaca mulatta , Transducción de Señal , Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Animales , Inmunoglobulina A/metabolismo , Inmunoglobulina A/inmunología , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/metabolismo , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/genética , Receptores Fc/metabolismo , Receptores Fc/genética , Membrana Mucosa/inmunología , Membrana Mucosa/metabolismo , Regulación hacia Arriba , Inmunidad Mucosa , Citotoxicidad Inmunológica , Células Cultivadas , Antígenos CDRESUMEN
BACKGROUND: MF59-adjuvanted gB subunit (gB/MF59) vaccine demonstrated approximately 50% efficacy against human cytomegalovirus (HCMV) acquisition in multiple clinical trials, suggesting that efforts to improve this vaccine design might yield a vaccine suitable for licensure. METHODS: A messenger RNA (mRNA)-based vaccine candidate encoding HCMV gB and pentameric complex (PC), mRNA-1647, is currently in late-stage efficacy trials. However, its immunogenicity has not been compared to the partially effective gB/MF59 vaccine. We assessed neutralizing and Fc-mediated immunoglobulin G (IgG) effector antibody responses induced by mRNA-1647 in both HCMV-seropositive and -seronegative vaccinees from a first-in-human clinical trial through 1 year following third vaccination using a systems serology approach. Furthermore, we compared peak anti-gB antibody responses in seronegative mRNA-1647 vaccinees to that of seronegative gB/MF59 vaccine recipients. RESULTS: mRNA-1647 vaccination elicited and boosted HCMV-specific IgG responses in seronegative and seropositive vaccinees, respectively, including neutralizing and Fc-mediated effector antibody responses. gB-specific IgG responses were lower than PC-specific IgG responses. gB-specific IgG and antibody-dependent cellular phagocytosis responses were lower than those elicited by gB/MF59. However, mRNA-1647 elicited higher neutralization and antibody-dependent cellular cytotoxicity (ADCC) responses. CONCLUSIONS: Overall, mRNA-1647 vaccination induced polyfunctional and durable HCMV-specific antibody responses, with lower gB-specific IgG responses but higher neutralization and ADCC responses compared to the gB/MF59 vaccine. CLINICAL TRIALS REGISTRATION: NCT03382405 (mRNA-1647) and NCT00133497 (gB/MF59).
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Adyuvantes Inmunológicos , Infecciones por Citomegalovirus , Vacunas contra Citomegalovirus , Citomegalovirus , Polisorbatos , Escualeno , Vacunas de ARNm , Humanos , Adyuvantes Inmunológicos/administración & dosificación , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos , Citomegalovirus/inmunología , Citomegalovirus/genética , Infecciones por Citomegalovirus/prevención & control , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Vacunas contra Citomegalovirus/administración & dosificación , Vacunas contra Citomegalovirus/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Vacunas de ARNm/administración & dosificación , Vacunas de ARNm/inmunología , Polisorbatos/administración & dosificación , ARN Mensajero/genética , ARN Mensajero/inmunología , Escualeno/administración & dosificación , Escualeno/inmunología , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/genéticaRESUMEN
BACKGROUND: Human cytomegalovirus (HCMV) is the most common infectious complication of organ transplantation and cause of birth defects worldwide. There are limited therapeutic options and no licensed vaccine to prevent HCMV infection or disease. To inform development of HCMV antibody-based interventions, a previous study identified individuals with potent and broad plasma HCMV-neutralizing activity, termed elite neutralizers (ENs), from a cohort of HCMV-seropositive (SP) blood donors. However, the specificities and functions of plasma antibodies associated with EN status remained undefined. METHODS: We sought to determine the plasma antibody specificities, breadth, and Fc-mediated antibody effector functions associated with the most potent HCMV-neutralizing responses in plasma from ENs (n = 25) relative to that from SP donors (n = 19). We measured antibody binding against various HCMV strains and glycoprotein targets and evaluated Fc-mediated effector functions, antibody-dependent cellular cytotoxicity (ADCC), and antibody-dependent cellular phagocytosis (ADCP). RESULTS: We demonstrate that ENs have elevated immunoglobulin G binding responses against multiple viral glycoproteins, relative to SP donors. Our study also revealed potent HCMV-specific antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis activity of plasma from ENs. CONCLUSIONS: We conclude that antibody responses against multiple glycoprotein specificities may be needed to achieve potent plasma neutralization and that potently HCMV elite-neutralizing plasma antibodies can also mediate polyfunctional responses.
Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Humanos , Inmunoglobulina G , Anticuerpos Neutralizantes , Formación de Anticuerpos , Anticuerpos Antivirales , Proteínas del Envoltorio ViralRESUMEN
A better understanding of the impact of early innate immune responses after vaccine priming on vaccine-elicited adaptive immune responses could inform rational design for effective HIV vaccines. The current study compared the whole blood molecular immune signatures of a 3M-052-SE adjuvanted HIV Env protein vaccine to a regimen combining the adjuvanted Env protein with simultaneous administration of a modified Vaccinia Ankara vector expressing HIV Env in infant rhesus macaques at days 0, 1, and 3 post vaccine prime. Both vaccines induced a rapid innate response, evident by elevated inflammatory plasma cytokines and altered gene expression. We identified 25 differentially-expressed genes (DEG) on day 1 compared to day 0 in the HIV protein vaccine group. In contrast, in the group that received both the Env protein and the MVA-Env vaccine only two DEG were identified, implying that the MVA-Env modified the innate response to the adjuvanted protein vaccine. By day 3, only three DEG maintained altered expression, indicative of the transient nature of the innate response. The DEG represented immune pathways associated with complement activation, type I interferon and interleukin signaling, pathogen sensing, and induction of adaptive immunity. DEG expression on day 1 was correlated to Env-specific antibody responses, in particular antibody-dependent cytotoxicity responses at week 34, and Env-specific follicular T helper cells. Results from network analysis supported the interaction of DEG and their proteins in B cell activation. These results emphasize that vaccine-induced HIV-specific antibody responses can be optimized through the modulation of the innate response to the vaccine prime.
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Vacunas contra el SIDA , Anticuerpos Anti-VIH/sangre , Infecciones por VIH , Proteínas del Envoltorio Viral/inmunología , Adyuvantes Inmunológicos/farmacología , Animales , Productos del Gen env , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/prevención & control , Humanos , Macaca mulatta , Vacunación , Virus Vaccinia/genéticaRESUMEN
Background: Subnormothermic machine perfusion (SNMP) of liver grafts is currently less clinically developed than normothermic and hypothermic approaches, but may have logistical advantages. At intermediate temperatures, the oxygen demand of the graft is low enough to be satisfied with an acellular perfusate, obviating the need for oxygen carrying molecules. This intermediate metabolic rate, however, is sufficient to support the production of bile, which is emerging as an important indicator of graft injury and viability. In this study, we hypothesized that the biliary compartment would be more sensitive than perfusate in detecting graft injury during SNMP. Methods: To test this hypothesis in a rat model, we performed liver transplants with DCD and control liver grafts after 1 h of acellular room temperature machine perfusion (acRTMP) or static cold storage (SCS). Point of care liver function tests were measured in biliary and perfusate samples after 1 h of machine perfusion. Following transplantation, rats were sacrificed at 24 h for assessment of post-transplant graft function and histology. Results: All point-of-care liver function tests were significantly more concentrated in the biliary compartment than the perfusate compartment during acRTMP. DCD liver grafts could be distinguished from control liver grafts by significantly higher markers of hepatocyte injury (AST, ALT) in the biliary compartment, but not in the perfusate compartment. Classical markers of cholangiocyte injury, such as gammy-glut amyl transferase (GGT), amylase (AML), and alkaline phosphatase were detectable in the biliary compartment, but not in the perfusate compartment. In comparison to SCS, graft preservation by acRTMP produced a significant survival benefit in DCD liver transplantation (75 vs. 0%, p < 0.0030). Conclusion: Together, these findings demonstrate that during acRTMP, the biliary compartment may be a more sensitive indicator of graft injury than the perfusate compartment. Moreover, acRTMP provides superior graft preservation to SCS in rat DCD liver transplantation.
RESUMEN
Human cytomegalovirus (HCMV) is the most common congenital infection. A glycoprotein B (gB) subunit vaccine (gB/MF59) is the most efficacious clinically tested to date, having achieved 50% protection against primary infection of HCMV-seronegative women. We previously identified that gB/MF59 vaccination primarily elicits non-neutralizing antibody responses, with variable binding to gB genotypes, and protection associated with binding to membrane-associated gB. We hypothesized that gB-specific non-neutralizing antibody binding breadth and function are dependent on epitope and genotype specificity, and ability to interact with membrane-associated gB. We mapped twenty-four gB-specific monoclonal antibodies (mAbs) from naturally HCMV-infected individuals for gB domain specificity, genotype preference, and ability to mediate phagocytosis or NK cell activation. gB-specific mAbs were primarily specific for Domain II and demonstrated variable binding to gB genotypes. Two mAbs facilitated phagocytosis with binding specificities of Domain II and AD2. This investigation provides novel understanding on the relationship between gB domain specificity and antigenic variability on gB-specific antibody effector functions.
Asunto(s)
Anticuerpos Antivirales/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Proteínas del Envoltorio Viral/inmunología , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Especificidad de Anticuerpos , Citomegalovirus/genética , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/virología , Femenino , Humanos , Masculino , Proteínas del Envoltorio Viral/genética , Adulto JovenRESUMEN
A vaccine to prevent maternal acquisition of human cytomegalovirus (HCMV) during pregnancy is a primary strategy to reduce the incidence of congenital disease. The MF59-adjuvanted glycoprotein B (gB) protein subunit vaccine (gB/MF59) is the most efficacious vaccine tested to date for this indication. We previously identified that gB/MF59 vaccination elicited poor neutralizing antibody responses and an immunodominant response against gB antigenic domain 3 (AD-3). Thus, we sought to test novel gB vaccines to improve functional antibody responses and reduce AD-3 immunodominance. Groups of juvenile New Zealand White rabbits were administered 3 sequential doses of the full-length gB protein with an MF59-like squalene-based adjuvant, the gB ectodomain protein (lacking AD-3) with squalene adjuvant, or lipid nanoparticle (LNP)-encapsulated nucleoside-modified mRNA encoding full-length gB. All vaccines were highly immunogenic with similar kinetics and comparable peak gB-binding and functional antibody responses. The AD-3-immunodominant IgG response following human gB/MF59 vaccination was closely mimicked in rabbits. Though gB ectodomain subunit vaccination eliminated targeting of epitopes in AD-3, it did not improve vaccine-elicited neutralizing or nonneutralizing antibody functions. gB nucleoside-modified mRNA-LNP-immunized rabbits exhibited an enhanced durability of vaccine-elicited antibody responses. Furthermore, the gB mRNA-LNP vaccine enhanced the breadth of IgG binding responses against discrete gB peptides. Finally, low-magnitude gB-specific T cell activity was observed in the full-length gB protein and mRNA-LNP groups, though not in ectodomain-vaccinated rabbits. Altogether, these data suggest that the use of gB nucleoside-modified mRNA-LNP vaccines is a viable strategy for improving on the partial efficacy of gB/MF59 vaccination and should be further evaluated in preclinical models.IMPORTANCE Human cytomegalovirus (HCMV) is the most common infectious cause of infant birth defects, resulting in permanent neurological disability for one newborn child every hour in the United States. After more than a half century of research and development, we remain without a clinically licensed vaccine or immunotherapeutic to reduce the burden of HCMV-associated disease. In this study, we sought to improve upon the glycoprotein B protein vaccine (gB/MF59), the most efficacious HCMV vaccine evaluated in a clinical trial, via targeted modifications to either the protein structure or vaccine formulation. Utilization of a novel vaccine platform, nucleoside-modified mRNA formulated in lipid nanoparticles, increased the durability and breadth of vaccine-elicited antibody responses. We propose that an mRNA-based gB vaccine may ultimately prove more efficacious than the gB/MF59 vaccine and should be further evaluated for its ability to elicit antiviral immune factors that can prevent HCMV-associated disease.
Asunto(s)
Vacunas contra Citomegalovirus/inmunología , Citomegalovirus/inmunología , Proteínas del Envoltorio Viral/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Citomegalovirus/genética , Infecciones por Citomegalovirus/inmunología , Polisorbatos , ARN Mensajero/genética , ARN Mensajero/inmunología , Conejos , Escualeno/inmunología , Vacunación/métodos , Vacunas de Subunidad/inmunología , Proteínas del Envoltorio Viral/genéticaRESUMEN
BACKGROUND: Development of a cytomegalovirus (CMV) vaccine is a high priority. However, the ability of antibodies to protect against CMV infection is not well characterized. Studies of maternal antibodies in infants offer the potential to identify humoral correlates of protection against postnatal acquisition. METHODS: This hypothesis-generating study analyzed 29 Ugandan mother-infant pairs that were followed weekly for CMV acquisition. Seventeen mothers and no infants were infected with human immunodeficiency virus (HIV). We evaluated the association between CMV-specific immunoglobulin G (IgG) responses in mothers at the time of delivery and their infants' CMV status at 6 months of age. We also assessed levels of CMV-specific IgG in infants at 6 weeks of age. CMV-specific IgG responses in the mother-infant pairs were then analyzed on the basis of perinatal HIV exposure. RESULTS: We found similar levels of multiple CMV glycoprotein-specific IgG binding specificities and functions in mothers and infants, irrespective of perinatal HIV exposure or infant CMV status at 6 months of age. However, the glycoprotein B-specific IgG titer, measured by 2 distinct assays, was higher in infants without CMV infection and was moderately associated with delayed CMV acquisition. CONCLUSIONS: These data suggest that high levels of glycoprotein B-specific IgG may contribute to the partial protection against postnatal CMV infection afforded by maternal antibodies, and they support the continued inclusion of glycoprotein B antigens in CMV vaccine candidates.
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Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/prevención & control , Vacunas contra Citomegalovirus/inmunología , Citomegalovirus/inmunología , Inmunidad Humoral , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos , Infecciones por VIH/complicaciones , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulinas Intravenosas , Lactante , Madres , Uganda , Proteínas del Envoltorio Viral/inmunologíaRESUMEN
Global elimination of pediatric human immunodeficiency virus (HIV) infections will require the development of novel immune-based approaches, and understanding infant immunity to HIV is critical to guide the rational design of these intervention strategies. Despite their immunological immaturity, chronically HIV-infected children develop broadly neutralizing antibodies (bnAbs) more frequently and earlier than adults do. However, the ontogeny of humoral responses during acute HIV infection is poorly defined in infants and challenging to study in human cohorts due to the presence of maternal antibodies. To further our understanding of age-related differences in the development of HIV-specific immunity during acute infection, we evaluated the generation of virus-specific humoral immune responses in infant (n = 6) and adult (n = 12) rhesus macaques (RMs) infected with a transmitted/founder (T/F) simian-human immunodeficiency virus (SHIV) (SHIV.C.CH505 [CH505]). The plasma HIV envelope-specific IgG antibody kinetics were similar in SHIV-infected infant and adult RMs, with no significant differences in the magnitude or breadth of these responses. Interestingly, autologous tier 2 virus neutralization responses also developed with similar frequencies and kinetics in infant and adult RMs, despite infants exhibiting significantly higher follicular T helper cell (Tfh) and germinal center B cell frequencies than adults. Finally, we show that plasma viral load was the strongest predictor of the development of autologous virus neutralization in both age groups. Our results indicate that the humoral immune response to SHIV infection develops with similar kinetics among infant and adult RMs, suggesting that the early-life immune system is equipped to respond to HIV-1 and promote the production of neutralizing HIV antibodies.IMPORTANCE There is a lack of understanding of how the maturation of the infant immune system influences immunity to HIV infection or how these responses differ from those of adults. Improving our knowledge of infant HIV immunity will help guide antiviral intervention strategies that take advantage of the unique infant immune environment to successfully elicit protective immune responses. We utilized a rhesus macaque model of SHIV infection as a tool to distinguish the differences in HIV humoral immunity in infants versus adults. Here, we demonstrate that the kinetics and quality of the infant humoral immune response to HIV are highly comparable to those of adults during the early phase of infection, despite distinct differences in their Tfh responses, indicating that slightly different mechanisms may drive infant and adult humoral immunity.
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Factores de Edad , Formación de Anticuerpos , Anticuerpos Anti-VIH/sangre , Infecciones por VIH/inmunología , VIH/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Linfocitos B/inmunología , Modelos Animales de Enfermedad , Centro Germinal/inmunología , Inmunoglobulina G/sangre , Macaca mulatta , Plasma/virología , Linfocitos T/inmunología , Carga ViralRESUMEN
The benefits of mucosal vaccines over injected vaccines are difficult to ascertain, since mucosally administered vaccines often induce serum antibody responses of lower magnitude than those induced by injected vaccines. This study aimed to determine if mucosal vaccination using a modified vaccinia virus Ankara expressing human immunodeficiency virus type 1 (HIV-1) gp120 (MVAgp120) prime and a HIV-1 gp120 protein boost could be optimized to induce serum antibody responses similar to those induced by an intramuscularly (i.m.) administered MVAgp120 prime/gp120 boost to allow comparison of an i.m. immunization regimen to a mucosal vaccination regimen for the ability to protect against a low-dose rectal simian-human immunodeficiency virus (SHIV) challenge. A 3-fold higher antigen dose was required for intranasal (i.n.) immunization with gp120 to induce serum anti-gp120 IgG responses not significantly different than those induced by i.m. immunization. gp120 fused to the adenovirus type 2 fiber binding domain (gp120-Ad2F), a mucosal targeting ligand, exhibited enhanced i.n. immunogenicity compared to gp120. MVAgp120 was more immunogenic after i.n. delivery than after gastric or rectal delivery. Using these optimized vaccines, an i.n. MVAgp120 prime/combined i.m. (gp120) and i.n. (gp120-Ad2F) boost regimen (i.n./i.m.-plus-i.n.) induced serum anti-gp120 antibody titers similar to those induced by the intramuscular prime/boost regimen (i.m./i.m.) in rabbits and nonhuman primates. Despite the induction of similar systemic anti-HIV-1 antibody responses, neither the i.m./i.m. nor the i.n./i.m.-plus-i.n. regimen protected against a repeated low-dose rectal SHIV challenge. These results demonstrate that immunization regimens utilizing the i.n. route are able to induce serum antigen-specific antibody responses similar to those induced by systemic immunization.IMPORTANCE Mucosal vaccination is proposed as a method of immunization able to induce protection against mucosal pathogens that is superior to protection provided by parenteral immunization. However, mucosal vaccination often induces serum antigen-specific immune responses of lower magnitude than those induced by parenteral immunization, making the comparison of mucosal and parenteral immunization difficult. We identified vaccine parameters that allowed an immunization regimen consisting of an i.n. prime followed by boosters administered by both i.n. and i.m. routes to induce serum antibody responses similar to those induced by i.m. prime/boost vaccination. Additional studies are needed to determine the potential benefit of mucosal immunization for HIV-1 and other mucosally transmitted pathogens.
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Vacunas contra el SIDA/inmunología , Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Inmunización Secundaria , Vacunación , Virus Vaccinia/inmunología , Vacunas contra el SIDA/genética , Administración Intranasal , Animales , Proteína gp120 de Envoltorio del VIH/genética , VIH-1/genética , Humanos , Inmunidad Mucosa , Ratones , Virus Vaccinia/genéticaRESUMEN
Studies in animal models are essential prerequisites for clinical trials of candidate HIV vaccines. Small animals, such as rabbits, are used to evaluate promising strategies prior to further immunogenicity and efficacy testing in nonhuman primates. Our goal was to determine how HIV-specific vaccine-elicited antibody responses, epitope specificity, and Fc-mediated functions in the rabbit model can predict those in the rhesus macaque (RM) model. Detailed comparisons of the HIV-1-specific IgG response were performed on serum from rabbits and RM given identical modified vaccinia virus Ankara-prime/gp120-boost immunization regimens. We found that vaccine-induced neutralizing antibody, gp120-binding antibody levels and immunodominant specificities, antibody-dependent cellular phagocytosis of HIV-1 virions, and antibody-dependent cellular cytotoxicity (ADCC) responses against gp120-coated target cells were similar in rabbits and RM. However, we also identified characteristics of humoral immunity that differed across species. ADCC against HIV-infected target cells was elicited in rabbits but not in RM, and we observed differences among subdominantly targeted epitopes. Human Fc receptor binding assays and analysis of antibody-cell interactions indicated that rabbit vaccine-induced antibodies effectively recruited and activated human natural killer cells, while vaccine-elicited RM antibodies were unable to activate either human or RM NK cells. Thus, our data demonstrate that both Fc-independent and Fc-dependent functions of rabbit antibodies can be measured with commonly used in vitro assays; however, the ability of immunogenicity studies performed in rabbits to predict responses in RM will vary depending on the particular immune parameter of interest.IMPORTANCE Nonneutralizing antibody functions have been associated with reduced infection risk, or control of virus replication, for HIV-1 and related viruses. It is therefore critical to evaluate development of these responses throughout all stages of preclinical testing. Rabbits are conventionally used to evaluate the ability of vaccine candidates to safely elicit antibodies that bind and neutralize HIV-1. However, it remained unexplored how effectively rabbits model the development of nonneutralizing antibody responses in primates. We administered identical HIV-1 vaccine regimens to rabbits and rhesus macaques and performed detailed comparisons of vaccine-induced antibody responses. We demonstrated that nonneutralizing HIV-specific antibody responses can be studied in the rabbit model and have identified aspects of these responses that are common, and those that are unique, to rabbits and rhesus macaques. Our findings will help determine how to best utilize preclinical rabbit and rhesus macaque models to accelerate HIV vaccine candidate testing in human trials.
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Vacunas contra el SIDA/inmunología , Anticuerpos Neutralizantes/inmunología , VIH-1/inmunología , Animales , Anticuerpos Neutralizantes/metabolismo , Formación de Anticuerpos , Subgrupos de Linfocitos B/metabolismo , Modelos Animales de Enfermedad , Epítopos , Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/virología , Seropositividad para VIH , Humanos , Macaca mulatta , Conejos , Especificidad de la EspecieRESUMEN
The majority of human immunodeficiency virus (HIV) type 1 infections in infants are acquired orally through breastfeeding. Toward development of a pediatric HIV vaccine to prevent breastmilk transmission, we tested the efficacy of a simultaneous oral and intramuscular (IM) vaccination regimen for preventing oral simian immunodeficiency virus (SIV) transmission in infant rhesus macaques. Two groups of neonatal macaques were immunized with DNA encoding SIV virus-like particles (DNA-SIV) on weeks 0 and 3, then boosted with modified vaccinia Ankara (MVA) virus expressing SIV antigens (MVA-SIV) on weeks 6 and 9. One group was prime/boosted by the IM route only. Another group was immunized with DNA by both the IM and topical oral (O) buccal routes, and boosted with MVA-SIV by both the IM and sublingual (SL) routes. A third group of control animals received saline by O + IM routes on weeks 0 and 3, and empty MVA by SL + IM routes on weeks 6 and 9. On week 12, infants were orally challenged once weekly with SIVmac251 until infected. The vaccine regimen that included oral routes resulted in reduced peak viremia. The rate of infection acquisition in vaccinated infants was found to be associated with prechallenge intestinal immunoglobulin G (IgG) responses to SIV gp120 and V1V2. Peak viremia was inversely correlated with postinfection intestinal IgG responses to gp120, gp41, and V1V2. These results suggest that codelivery of a pediatric HIV vaccine by an oral route may be superior to IM-only regimens for generating mucosal antibodies and preventing HIV breastmilk transmission in neonates.
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Glicoproteínas de Membrana/inmunología , Boca/virología , Vacunas contra el SIDAS/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida del Simio/terapia , Virus de la Inmunodeficiencia de los Simios/inmunología , Vacunación/métodos , Virus Vaccinia/genética , Proteínas del Envoltorio Viral/inmunología , Administración Oral , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/inmunología , Modelos Animales de Enfermedad , Infecciones por VIH/terapia , Inmunoglobulina G/metabolismo , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Inyecciones Intramusculares , Macaca mulatta , Boca/efectos de los fármacos , Membrana Mucosa/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Viremia/tratamiento farmacológicoRESUMEN
Human cytomegalovirus (HCMV) is the most common congenital infection worldwide, frequently causing hearing loss and brain damage in afflicted infants. A vaccine to prevent maternal acquisition of HCMV during pregnancy is necessary to reduce the incidence of infant disease. The glycoprotein B (gB) + MF59 adjuvant subunit vaccine platform is the most successful HCMV vaccine tested to date, demonstrating â¼50% efficacy in preventing HCMV acquisition in multiple phase 2 trials. However, the mechanism of vaccine protection remains unknown. Plasma from 33 postpartum women gB/MF59 vaccinees at peak immunogenicity was tested for gB epitope specificity as well as neutralizing and nonneutralizing anti-HCMV effector functions and compared with an HCMV-seropositive cohort. gB/MF59 vaccination elicited IgG responses with gB-binding magnitude and avidity comparable to natural infection. Additionally, IgG subclass distribution was similar with predominant IgG1 and IgG3 responses induced by gB vaccination and HCMV infection. However, vaccine-elicited antibodies exhibited limited neutralization of the autologous virus, negligible neutralization of multiple heterologous strains, and limited binding responses against gB structural motifs targeted by neutralizing antibodies including AD-1, AD-2, and domain I. Vaccinees had high-magnitude IgG responses against AD-3 linear epitopes, demonstrating immunodominance against this nonneutralizing, cytosolic region. Finally, vaccine-elicited IgG robustly bound membrane-associated gB on the surface of transfected or HCMV-infected cells and mediated virion phagocytosis, although were poor mediators of NK cell activation. Altogether, these data suggest that nonneutralizing antibody functions, including virion phagocytosis, likely played a role in the observed 50% vaccine-mediated protection against HCMV acquisition.
Asunto(s)
Anticuerpos Neutralizantes/inmunología , Infecciones por Citomegalovirus/inmunología , Vacunas contra Citomegalovirus/inmunología , Citomegalovirus/inmunología , Vacunas de Subunidad/inmunología , Proteínas del Envoltorio Viral/inmunología , Adulto , Anticuerpos Antivirales/inmunología , Células Cultivadas , Epítopos/inmunología , Femenino , Humanos , Inmunoglobulina G/inmunología , Polisorbatos , Escualeno/inmunología , Adulto JovenRESUMEN
BACKGROUND: The initial envelope (Env)-specific antibody response in acutely HIV-1-infected individuals and simian immunodeficiency virus (SIV)-infected rhesus monkeys (RMs) is dominated by non-neutralizing antibodies targeting Env gp41. In contrast, natural primate SIV hosts, such as African green monkeys (AGMs), develop a predominant Env gp120-specific antibody response to SIV infection. However, the fine-epitope specificity and function of SIV Env-specific plasma IgG, and their potential role on autologous virus co-evolution in SIV-infected AGMs and RMs remain unclear. RESULTS: Unlike the dominant linear gp41-specific IgG responses in RMs, SIV-infected AGMs demonstrated a unique linear variable loop 2 (V2)-specific plasma IgG response that arose concurrently with high gp120-directed antibody-dependent cellular cytotoxicity (ADCC) activity, and SIVsab-infected cell binding responses during acute infection. Moreover, SIV variants isolated from SIV-infected AGMs exhibited high amino acid mutation frequencies within the Env V1V2 loop compared to those of RMs. Notably, the linear V2-specific IgG epitope in AGMs overlaps with an analogous region of the HIV V2 loop containing the K169 mutation epitope identified in breakthrough viruses from RV144 vaccinees. CONCLUSION: Vaccine-elicited Env V2-specific IgG responses have been proposed as an immune correlate of reduced risk in HIV-1/SIV acquisition in humans and RMs. Yet the pathways to elicit these potentially-protective V2-specific IgG responses remain unclear. In this study, we demonstrate that SIV-infected AGMs, which are the natural hosts of SIV, exhibited high plasma linear V2-specific IgG binding responses that arose concurrently with SIV Env gp120-directed ADCC-mediating, and SIV-infected cell plasma IgG binding responses during acute SIV infection, which were not present in acutely SIV-infected RMs. The linear V2-specific antibody response in AGMs targets an overlapping epitope of the proposed site of vaccine-induced immune pressure defined in the moderately protective RV144 HIV-1 vaccine trial. Identifying host factors that control the early elicitation of Env V2-specific IgG and ADCC antibody responses in these natural SIV hosts could inform vaccination strategies aimed at rapidly inducing potentially-protective HIV-1 Env-specific responses in humans.
Asunto(s)
Anticuerpos Antivirales/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos , Epítopos/inmunología , Productos del Gen env/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Enfermedad Aguda , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Chlorocebus aethiops , Productos del Gen env/genética , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Cinética , Mutación , Péptidos/inmunología , Unión Proteica/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genéticaRESUMEN
Human immunodeficiency virus (HIV) type 1 uses the CD4 molecule as its principal receptor to infect T cells. HIV-1 integrates its viral genome into the host cell, leading to persistent infection wherein HIV-1 can remain transcriptionally silent in latently infected CD4+ T cells. On reactivation of replication-competent provirus, HIV-1 envelope glycoproteins (Env) are expressed and accumulate on the cell surface, allowing infected cells to be detected and targeted by endogenous immune responses or immune interventions. HIV-1 Env-specific antibodies have the potential to bind HIV-1 cell surface Env and promote elimination of infected CD4+ T cells by recruiting cytotoxic effector cells, such as natural killer cells, monocytes, and polymorphonuclear cells. Harnessing humoral and innate cellular responses has become one focus of research to develop innovative strategies to recruit and redirect cytotoxic effector cells to eliminate the HIV-1 latently infected CD4+ T-cell reservoir.
Asunto(s)
Inmunidad Adaptativa , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/terapia , VIH-1/inmunología , Inmunidad Celular , Inmunidad Innata , Inmunoterapia/métodos , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/fisiología , Humanos , Latencia del VirusRESUMEN
African green monkeys (AGMs) are natural primate hosts of simian immunodeficiency virus (SIV). Interestingly, features of the envelope-specific antibody responses in SIV-infected AGMs are distinct from that of HIV-infected humans and SIV-infected rhesus monkeys, including gp120-focused responses and rapid development of autologous neutralization. Yet, the lack of genetic tools to evaluate B-cell lineages hinders potential use of this unique non-human primate model for HIV vaccine development. Here we define features of the AGM Ig loci and compare the proportion of Env-specific memory B-cell populations to that of HIV-infected humans and SIV-infected rhesus monkeys. AGMs appear to have a higher proportion of Env-specific memory B cells that are mainly gp120 directed. Furthermore, AGM gp120-specific monoclonal antibodies display robust antibody-dependent cellular cytotoxicity and CD4-dependent virion capture activity. Our results support the use of AGMs to model induction of functional gp120-specific antibodies by HIV vaccine strategies.
Asunto(s)
Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Antivirales/biosíntesis , Linfocitos B/inmunología , Inmunoglobulinas/biosíntesis , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Anticuerpos Neutralizantes/química , Anticuerpos Antivirales/química , Linfocitos B/virología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Chlorocebus aethiops , Enfermedad Crónica , Citotoxicidad Inmunológica , Variación Genética , Proteína gp120 de Envoltorio del VIH/inmunología , Humanos , Inmunidad Celular , Inmunoglobulinas/clasificación , Memoria Inmunológica , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Virión/inmunología , Virión/patogenicidadRESUMEN
An HIV-1 DNA prime vaccine, with a recombinant adenovirus type 5 (rAd5) boost, failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than to gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells responded to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies were non-neutralizing and frequently polyreactive with host and environmental antigens, including intestinal microbiota (IM). Next-generation sequencing of an immunoglobulin heavy chain variable region repertoire before vaccination revealed an Env-IM cross-reactive Ab that was clonally related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy.
Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos Anti-VIH/inmunología , Proteína gp41 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Microbiota/inmunología , Vacunas de ADN/inmunología , Adenoviridae , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Formación de Anticuerpos , Reacciones Cruzadas , Anticuerpos Anti-VIH/genética , Proteína gp120 de Envoltorio del VIH/inmunología , Proteína gp41 de Envoltorio del VIH/genética , Humanos , Inmunidad , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Memoria Inmunológica , Intestinos/microbiologíaRESUMEN
HIV-1 mucosal transmission begins with virus or virus-infected cells moving through mucus across mucosal epithelium to infect CD4+ T cells. Although broadly neutralizing antibodies (bnAbs) are the type of HIV-1 antibodies that are most likely protective, they are not induced with current vaccine candidates. In contrast, antibodies that do not neutralize primary HIV-1 strains in the TZM-bl infection assay are readily induced by current vaccine candidates and have also been implicated as secondary correlates of decreased HIV-1 risk in the RV144 vaccine efficacy trial. Here, we have studied the capacity of anti-Env monoclonal antibodies (mAbs) against either the immunodominant region of gp41 (7B2 IgG1), the first constant region of gp120 (A32 IgG1), or the third variable loop (V3) of gp120 (CH22 IgG1) to modulate in vivo rectal mucosal transmission of a high-dose simian-human immunodeficiency virus (SHIV-BaL) in rhesus macaques. 7B2 IgG1 or A32 IgG1, each containing mutations to enhance Fc function, was administered passively to rhesus macaques but afforded no protection against productive clinical infection while the positive control antibody CH22 IgG1 prevented infection in 4 of 6 animals. Enumeration of transmitted/founder (T/F) viruses revealed that passive infusion of each of the three antibodies significantly reduced the number of T/F genomes. Thus, some antibodies that bind HIV-1 Env but fail to neutralize virus in traditional neutralization assays may limit the number of T/F viruses involved in transmission without leading to enhancement of viral infection. For one of these mAbs, gp41 mAb 7B2, we provide the first co-crystal structure in complex with a common cyclical loop motif demonstrated to be critical for infection by other retroviruses.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Virus de la Inmunodeficiencia de los Simios/inmunología , Proteínas del Envoltorio Viral/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Técnica del Anticuerpo Fluorescente , VIH-1/inmunología , Humanos , Mucosa Intestinal/virología , Macaca mulatta , Conformación Proteica , Recto , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Resonancia por Plasmón de Superficie , Proteínas del Envoltorio Viral/químicaRESUMEN
We previously demonstrated that vaccination of lactating rhesus monkeys with a DNA prime/vector boost strategy induces strong T-cell responses but limited envelope (Env)-specific humoral responses in breast milk. To improve vaccine-elicited antibody responses in milk, hormone-induced lactating rhesus monkeys were vaccinated with a transmitted/founder (T/F) HIV Env immunogen in a prime-boost strategy modeled after the moderately protective RV144 HIV vaccine. Lactating rhesus monkeys were intramuscularly primed with either recombinant DNA (n = 4) or modified vaccinia virus Ankara (MVA) poxvirus vector (n = 4) expressing the T/F HIV Env C.1086 and then boosted twice intramuscularly with C.1086 gp120 and the adjuvant MF59. The vaccines induced Env-binding IgG and IgA as well as neutralizing and antibody-dependent cellular cytotoxicity (ADCC) responses in plasma and milk of most vaccinated animals. Importantly, plasma neutralization titers against clade C HIV variants MW965 (P = 0.03) and CAP45 (P = 0.04) were significantly higher in MVA-primed than in DNA-primed animals. The superior systemic prime-boost regimen was then compared to a mucosal-boost regimen, in which animals were boosted twice intranasally with C.1086 gp120 and the TLR 7/8 agonist R848 following the same systemic prime. While the systemic and mucosal vaccine regimens elicited comparable levels of Env-binding IgG antibodies, mucosal immunization induced significantly stronger Env-binding IgA responses in milk (P = 0.03). However, the mucosal regimen was not as potent at inducing functional IgG responses. This study shows that systemic MVA prime followed by either intranasal or systemic protein boosts can elicit strong humoral responses in breast milk and may be a useful strategy to interrupt postnatal HIV-1 transmission.