Particulate aluminum salts have long occupied a central place worldwide as inexpensive immunostimulatory adjuvants that enable induction of protective immunity for vaccines. Despite their huge benefits and safety, the particulate structures of aluminum salts require transportation and storage at temperatures between 2 °C and 8 °C, and they all have exquisite sensitivity to damage caused by freezing. Here, we propose to solve the critical freezing vulnerability of particulate aluminum salt adjuvants by introducing soluble aluminum salts as adjuvants.
View Article and Find Full Text PDFAn unconjugated composite peptide vaccine targeting multiple conserved influenza epitopes from hemagglutinin, neuraminidase, and matrix protein and formulated with a safe and highly potent adjuvant, Army Liposome formulation (ALFQ), generated broad and durable immune responses in outbred mice. The antibodies recognized specific epitopes in influenza peptides and several human, avian, and swine influenza viruses. Comparable antibody responses to influenza viruses were observed with intramuscular and intradermal routes of vaccine administration.
View Article and Find Full Text PDFArmy Liposome Formulation with QS21 (ALFQ), a vaccine adjuvant preparation, comprises liposomes containing saturated phospholipids, with 55 mol% cholesterol relative to the phospholipids, and two adjuvants, monophosphoryl lipid A (MPLA) and QS21 saponin. A unique feature of ALFQ is the formation of giant unilamellar vesicles (GUVs) having diameters >1.0 µm, due to a remarkable fusion event initiated during the addition of QS21 to nanoliposomes containing MPLA and 55 mol% cholesterol relative to the total phospholipids.
View Article and Find Full Text PDFA vaccine adjuvant known as Adjuvant System 01 (AS01) consists of liposomes containing a mixture of natural congeners of monophosphoryl lipid A (MPL) obtained from bacterial lipopolysaccharide, and a tree saponin known as QS21. Two vaccines containing AS01 as the adjuvant have been licensed, including a malaria vaccine (Mosquirix) approved by World Health. Organization and European Medicines Agency for use in sub-Saharan Africa, and a shingles vaccine (Shingrix) approved by the U.
View Article and Find Full Text PDFMonocyte-derived macrophages (MDM) are highly permissive to HIV-1 infection potentially due to the downregulation of innate factors during the differentiation process. The environmental milieu and innate anti-viral factors which are modulated during macrophage differentiation, have been associated with their increased permissiveness to HIV-1 infection. Here, we demonstrate that the Army Liposome Formulation containing MPLA, and QS-21 (ALFQ) activated MDM that are normally permissive to HIV-1 infection to generate a proinflammatory environment and upregulated anti-viral factors notably APOBEC3A.
View Article and Find Full Text PDFMalaria transmission-blocking vaccines candidates based on Pfs25 and Pfs230 have advanced to clinical studies. Exoprotein A (EPA) conjugate of Pfs25 in Alhydrogel developed functional immunity in humans, with limited durability. Pfs230 conjugated to EPA (Pfs230D1-EPA) with liposomal adjuvant AS01 is currently in clinical trials in Mali.
View Article and Find Full Text PDFOpioid use disorder (OUD) is a serious health problem that has dramatically increased over the last decade. Although current therapies for the management of OUD can be effective, they have limitations. The complementary strategy to combat the opioid crisis is the development of a conjugate vaccine to generate high affinity antibodies in order to neutralize opioids in circulation before reaching the brain.
View Article and Find Full Text PDFA universal influenza candidate vaccine that targets multiple conserved influenza virus epitopes from hemagglutinin (HA), neuraminidase (NA) and matrix (M2e) proteins was combined with the potent Army liposomal adjuvant (ALFQ) to promote induction of broad immunity to seasonal and pandemic influenza strains. The unconjugated and CRM-conjugated composite peptides formulated with ALFQ were highly immunogenic and induced both humoral and cellular immune responses in mice. Broadly reactive serum antibodies were induced across various IgG isotypes.
View Article and Find Full Text PDFThe most advanced malaria vaccine, RTS,S, includes the central repeat and C-terminal domains of the circumsporozoite protein (PfCSP). We have recently isolated human antibodies that target the junctional region between the N-terminal and repeat domains that are not included in RTS,S. Due to the fact that these antibodies protect against malaria challenge in mice, their epitopes could be effective vaccine targets.
View Article and Find Full Text PDFThirty-four historical achievements since 1970 that emanated from scientific research at the Walter Army Institute of Research are identified and documented. Impact areas include vaccines, drug development, and clinical assays to prevent or treat infectious diseases; neuropsychiatric management of warrior performance and combat casualty; blood delivery management; and radiation protection.
View Article and Find Full Text PDFDevelopment of liposome-based formulations as vaccine adjuvants has been intimately associated with, and dependent on, and informed by, a fundamental understanding of biochemical and biophysical properties of liposomes themselves. The Walter Reed Army Institute of Research (WRAIR) has a fifty-year history of experience of basic research on liposomes; and development of liposomes as drug carriers; and development of liposomes as adjuvant formulations for vaccines. Uptake of liposomes by phagocytic cells in vitro has served as an excellent model for studying the intracellular trafficking patterns of liposomal antigen.
View Article and Find Full Text PDFTo augment HIV-1 pox-protein vaccine immunogenicity using a next generation adjuvant, a prime-boost strategy of recombinant modified vaccinia virus Ankara and multimeric Env gp145 was evaluated in macaques with either aluminum (alum) or a novel liposomal monophosphoryl lipid A (MPLA) formulation adsorbed to alum, ALFA. Binding antibody responses were robust and comparable between arms, while antibody-dependent neutrophil and monocyte phagocytotic responses were greatly enhanced by ALFA. Per-exposure vaccine efficacy against heterologous tier 2 SHIV mucosal challenge was 90% in ALFA-adjuvanted males (P = 0.
View Article and Find Full Text PDF: From its earliest days, the US. military has embraced the use of vaccines to fight infectious diseases. The Army Liposome Formulation (ALF) has been a pivotal innovation as a vaccine adjuvant that provides excellent safety and potency and could lead to dual-use military and civilian benefits.
View Article and Find Full Text PDFAntibodies to Circumsporozoite protein (CSP) confer protection against controlled human malaria infection (CHMI) caused by the parasite Plasmodium falciparum. Although CSP is highly immunogenic, it does not induce long lasting protection and efforts to improve CSP-specific immunological memory and duration of protection are underway. We have previously reported that the clinical grade CSP vaccine FMP013 was immunogenic and protective against malaria challenge in mice when combined with the Army Liposomal Formulation adjuvant containing immune modulators 3D-PHAD™ and QS21 (ALFQ).
View Article and Find Full Text PDFis among the most common causes of diarrheal disease worldwide and efforts to develop protective measures against the pathogen are ongoing. One of the few defined virulence factors targeted for vaccine development is the capsule polysaccharide (CPS). We have developed a capsule conjugate vaccine against strain 81-176 (CPS-CRM) that is immunogenic in mice and nonhuman primates (NHPs) but only moderately immunogenic in humans when delivered alone or with aluminum hydroxide.
View Article and Find Full Text PDFLeishmaniasis is an expanding health threat worldwide complicated by the absence of an effective vaccine. We investigated transcutaneous immunization (TCI) as a needle-free immunization route which exploits the abundance of antigen presenting cells in the skin to induce both mucosal and systemic immunity. Leishmania (L.
View Article and Find Full Text PDFLiposomes containing cholesterol and monophosphoryl lipid A (such as ALFQ and AS01B) are vaccine adjuvants. During construction of the formulations, addition of QS21 to nano-size (50-100 nm) liposomes resulted in extremely large (up to ∼30 µm) liposomes in ALFQ, but AS01B liposomes remained small nano-vesicles. Here, we show that saturation of phospholipid chains is essential for production of large liposomes by QS21.
View Article and Find Full Text PDFBackground: In the RV144 trial, human immunodeficiency virus (HIV)-1 gp120 V1V2 antibodies correlated inversely with risk of HIV-1 infection; however, the titers waned quickly. We hypothesized that a more potent adjuvant might enhance the magnitude and durability of V1V2 antibodies.
Methods: We examined archived sera from a phase I randomized, double-blind placebo-controlled trial, conducted in HIV-1-uninfected individuals, vaccinated with HIV-1SF-2 rgp120 either adsorbed to aluminum hydroxide (aluminum hydroxide arm) or encapsulated in liposomes containing monophosphoryl lipid A (MPL®) and then adsorbed to aluminum hydroxide (liposomal arm).
We describe for the first time a method that utilizes microscale thermophoresis (MST) technology to determine polyclonal antibody affinities to small molecules. Using a novel type of heterologous MST, we have accurately measured a solution-based binding affinity of serum antibodies to heroin which was previously impossible with other currently available methods. Moreover, this mismatch approach (i.
View Article and Find Full Text PDFAluminum salts have been used as vaccine adjuvants for >50 years, and they are currently present in at least 146 licensed vaccines worldwide. In this study we examined whether adsorption of Army Liposome Formulation (ALF) to an aluminum salt that already has an antigen adsorbed to it might result in improved immune potency of the aluminum-adsorbed antigen. ALF is composed of a family of anionic liposome-based adjuvants, in which the liposomes contain synthetic phospholipids having dimyristoyl fatty acyl groups, cholesterol and monophosphoryl lipid A (MPLA).
View Article and Find Full Text PDFA synthetic heroin analog (MorHap) and a synthetic 42 amino acid V2 loop peptide from A/E strain of HIV-1 gp120 envelope protein that was previously used in a successful phase III vaccine trial were constructed as antigens together with liposomes containing monophosphoryl lipid A as an adjuvant, to explore the feasibility of producing a dual use vaccine both for treatment of heroin addiction and prevention of HIV-1 infection among injection drug users. The V2 peptide was tethered by a palmitoyl fatty acyl tail embedded in the liposomal lipid bilayer, and the heroin analog was conjugated to tetanus toxoid as a carrier protein that was mixed with the adjuvant. Upon comparison of a linear V2 peptide with a cyclic peptide, differences were found in the secondary configurations by circular dichroism, with the tethered cyclic peptide (palm-cyclic peptide) entirely in a random coil, and the tethered linear V2 peptide (palm-linear V2 peptide) entirely in a beta-sheet.
View Article and Find Full Text PDFAn improved synthesis of a haptenic heroin surrogate 1 (6-AmHap) is reported. The intermediate needed for the preparation of 1 was described in the route in the synthesis of 2 (DiAmHap). A scalable procedure was developed to install the C-3 amido group.
View Article and Find Full Text PDFMacrophages are a major target for human immunodeficiency virus type 1 (HIV-1) infection. However, macrophages are largely heterogeneous and may exhibit differences in permissiveness to HIV-1 infection. This study highlights the interplay of macrophage heterogeneity in HIV-1 pathogenesis.
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