Adjuvants for vaccines to drugs of abuse and addiction

Prime-boost-type PspA3 + 2 mucosal vaccine protects cynomolgus macaques from intratracheal challenge with pneumococci

BACKGROUND

Although vaccination is recommended for protection against invasive pneumococcal disease, the frequency of pneumococcal pneumonia is still high worldwide. In fact, no vaccines are effective for all pneumococcal serotypes. Fusion pneumococcal surface protein A (PspA) has been shown to induce a broad range of cross-reactivity with clinical isolates and afford cross-protection against pneumococcal challenge in mice. Furthermore, we developed prime-boost-type mucosal vaccines that induce both antigen-specific IgG in serum and antigen-specific IgA in targeted mucosal organs in previous studies. We investigated whether our prime-boost-type immunization with a fusion PspA was effective against pneumococcal infection in mice and cynomolgus macaques.

METHODS

C57BL/6 mice were intramuscularly injected with fusion PspA combined with CpG oligodeoxynucleotides and/or curdlan. Six weeks later, PspA was administered intranasally. Blood and bronchoalveolar lavage fluid were collected and antigen-specific IgG and IgA titers were measured. Some mice were given intranasal Streptococcus pneumoniae and the severity of infection was analyzed. Macaques were intramuscularly injected with fusion PspA combined with CpG oligodeoxynucleotides and/or curdlan at week 0 and week 4. Then, 13 or 41 weeks later, PspA was administered intratracheally. Blood and bronchoalveolar lavage fluid were collected and antigen-specific IgG and IgA titers were measured. Some macaques were intranasally administered S. pneumoniae and analyzed for the severity of pneumonia.

RESULTS

Serum samples from mice and macaques injected with antigens in combination with CpG oligodeoxynucleotides and/or curdlan contained antigen-specific IgG. Bronchial samples contained antigen-specific IgA after the fusion PspA boosting. This immunization regimen effectively prevented S. pneumoniae infection.

CONCLUSIONS

Prime-boost-type immunization with a fusion PspA prevented S. pneumoniae infection in mice and macaques.

Self-Adjuvanting TLR7/8 Agonist and Fentanyl Hapten Co-Conjugate Achieves Enhanced Protection against Fentanyl Challenge

Currently approved pharmacotherapies for opioid use disorders (OUDs) and overdose reversal agents are insufficient to slow the spread of OUDs due to the proliferation of fentanyl. This is evident in the 31% rise in drug overdose deaths from 2019 to 2022, with rates increasing from 21.6 to 28.3 overdoses per 100,000 deaths. Vaccines are a potential alternative or adjunct therapy for the treatment of several substance use disorders (nicotine, cocaine) but have shown limited clinical success due to suboptimal antibody titers. In this study, we demonstrate that coconjugation of a Toll-like receptor 7/8 (TLR7/8) agonist (UM-3006) alongside a fentanyl-based hapten (F1) on the surface of the carrier protein cross-reactive material 197 (CRM) significantly increased generation of high-affinity fentanyl-specific antibodies. This demonstrated enhanced protection against fentanyl challenges relative to an unconjugated (admix) adjuvant control in mice. Inclusion of aluminum hydroxide (alum) adjuvant further increased titers and enhanced protection, as determined by analysis of fentanyl concentration in serum and brain tissue. Collectively, our findings present a promising approach to enhance the efficacy of antiopioid vaccines, underscoring the need for extensive exploration of TLR7/8 agonist conjugates as a compelling strategy to combat opioid use disorders.

PheSom: a term frequency-based method for measuring human phenotype similarity on the basis of MeSH vocabulary

Background: Phenotype similarity calculation should be used to help improve drug repurposing. In this study, based on the MeSH terms describing the phenotypes deposited in OMIM, we proposed a method, namely, PheSom (Phenotype Similarity On MeSH), to measure the similarity between phenotypes. PheSom counted the number of overlapping MeSH terms between two phenotypes and then took the weight of every MeSH term within each phenotype into account according to the term frequency-inverse document frequency (FIDC). Phenotype-related genes were used for the evaluation of our method. Results: A 7,739 × 7,739 similarity score matrix was finally obtained and the number of phenotype pairs was dramatically decreased with the increase of similarity score. Besides, the overlapping rates of phenotype-related genes were remarkably increased with the increase of similarity score between phenotypes, which supports the reliability of our method. Conclusion: We anticipate our method can be applied to identifying novel therapeutic methods for complex diseases.

Tracing the recent updates on vaccination approaches and significant adjuvants being developed against HIV

INTRODUCTION

Human Immunodeficiency Virus type 1 (HIV1); the causative agent of Acquired Immunodeficiency Syndrome (AIDS), has been a major target of the scientific community to develop an anti-viral therapy. Some successful discoveries have been made during the last two decades in the form of availability of antiviral therapy in endemic regions. Nevertheless, a total cure and safety vaccine has not yet been designed to eradicate HIV from the world.

AREAS COVERED

The purpose of this comprehensive study is to compile recent data regarding therapeutic interventions against HIV and to determine future research needs in this field. A systematic research strategy has been used to gather data from recent, most advanced published electronic sources. Literature based results show that experiments at the invitro level and animal models are continuously in research annals and are providing hope for human trials.

EXPERT OPINION

There is still a gap and more work is needed in the direction of modern drug and vaccination designs. Moreover coordination is necessary among researchers, educationists, public health workers, and the general community to communicate and coordinate the repercussions associated with the deadly disease. It is important for taking timely measures regarding mitigation and adaptation with HIV in future.

In-depth review of delivery carriers associated with vaccine adjuvants: current status and future perspectives

INTRODUCTION

Vaccines are powerful tools for controlling microbial infections and preventing epidemics. To enhance the immune response to antigens, effective subunit vaccines or mRNA vaccines often require the combination of adjuvants or delivery carriers. In recent years, with the rapid development of immune mechanism research and nanotechnology, various studies based on the optimization of traditional adjuvants or various novel carriers have been intensified, and the construction of vaccine adjuvant delivery systems (VADS) with both adjuvant activity and antigen delivery has become more and more important in vaccine research.

AREAS COVERED

This paper reviews the common types of vaccine adjuvant delivery carriers, classifies the VADS according to their basic carrier types, introduces the current research status and future development trend, and emphasizes the important role of VADS in novel vaccine research.

EXPERT OPINION

As the number of vaccine types increases, conventional aluminum adjuvants show limitations in effectively stimulating cellular immune responses, limiting their use in therapeutic vaccines for intracellular infections or tumors. In contrast, the use of conventional adjuvants as VADS to carry immunostimulatory molecules or deliver antigens can greatly enhance the immune boosting effect of classical adjuvants. A comprehensive understanding of the various delivery vehicles will further facilitate the development of vaccine adjuvant research.

Anti-Cocaine IgA Rather Than IgG Mediates Vaccine Protection from Cocaine Use

In developing a vaccine for fentanyl use disorder, we observed that IgA was the best correlate of vaccine-mediated protection from injected drug challenge, rather than IgG or binding affinity. Recent evidence shows that IgA secreting cells line the blood−brain barrier that capture pathogens and could prevent drug antigens from penetrating the brain. We assayed IgA and IgG antibodies from an anti-cocaine vaccine clinical trial and categorized each subject’s antibody levels using half-log cut-points for IgA: <1000, <5000, <10,000 and >10,000; and for IgG: <10,000 to >100,000. We compared these antibody groups on urine toxicology in 130 subjects at week 9 after 3 booster vaccinations. We also provided relevant data on benzoylecgonine (BE, cocaine metabolite) from this study’s placebo patients. BE urine levels were lowest for the highest IgA category; however, levels did not differ across IgG groups. Our findings linking IgA to protection from cocaine and fentanyl in mice, rats and humans are novel and suggest an increasingly recognized role of IgA in vaccine efficacy.

Development of an Effective Monoclonal Antibody against Heroin and Its Metabolites Reveals Therapies Have Mistargeted 6-Monoacetylmorphine and Morphine over Heroin

The opioid epidemic is a global public health crisis that has failed to abate with current pharmaceutical treatments. Moreover, these FDA-approved drugs possess numerous problems such as adverse side effects, short half-lives, abuse potential, and recidivism after discontinued use. An alternative treatment model for opioid use disorders is immunopharmacotherapy, where antibodies are produced to inhibit illicit substances by sequestering the drug in the periphery. Immunopharmacotherapeutics against heroin have engaged both active and passive vaccines targeting heroin's metabolites, 6-monoacetylmorphine (6-AM) and morphine, since decades of research have stated that heroin's psychoactive and lethal effects are mainly attributed to these compounds. However, concerted efforts to develop effective immunopharmacotherapies against heroin abuse have faced little clinical advancement, suggesting a need for reassessing drug target selection. To address this issue, four unique monoclonal antibodies were procured with distinct affinity to either heroin, 6-AM, or morphine. Examination of these antibodies through in vitro and in vivo tests revealed monoclonal antibody 11D12 as the optimal therapeutic and provided crucial insights into the key chemical species to target for blunting heroin's psychoactive and lethal effects. These findings offer clarification into the problematic attempts of therapeutics targeting heroin's metabolites and provide a path forward for future heroin immunopharmacotherapy development.

Immunotherapies for the Treatment of Drug Addiction

Substance use disorders (SUD) are a serious public health concern globally. Existing treatment platforms suffer from a lack of effectiveness. The development of immunotherapies against these substances of abuse for both prophylactic and therapeutic use has gained tremendous importance as an alternative and/or supplementary to existing therapies. Significant development has been made in this area over the last few decades. Herein, we highlight the vaccine and other biologics development strategies, preclinical, clinical updates along with challenges and future directions. Articles were searched in PubMed, ClinicalTrial.gov, and google electronic databases relevant to development, preclinical, clinical trials of nicotine, cocaine, methamphetamine, and opioid vaccines. Various new emerging vaccine development strategies for SUD were also identified through this search and discussed. A good number of vaccine candidates demonstrated promising results in preclinical and clinical phases and support the concept of developing a vaccine for SUD. However, there have been no ultimate success as yet, and there remain some challenges with a massive push to take more candidates to clinical trials for further evaluation to break the bottleneck.

A Clinical Trial of Entolimod a TLR-5 Adjuvant for Vaccines Using Diphtheria or Tetanus as Carrier Proteins

Anti-drug vaccines previously failed clinical trials because they did not provide a sufficient titer or duration of antibodies (AB), but new adjuvants enhance both AB titers and efficacy duration. This clinical trial assessed AB titers after a single booster of commercial tetanus-diphtheria (Td) vaccine in 40 males randomized as 15 to Td alone and 25 to Td combined with the TLR5 adjuvant, Entolimod (Ent). Ent significantly increased ABs against diphtheria (DPT) (0.46 vs. 0.29 IU/mL increase; n = 40, p < 0.05), but against tetanus (TT) only if baseline TT AB was below 3 IU/mL (3.1 vs. 2.1 IU/mL; n = 20; p < 0.05). These 20 participants also showed a two-fold increase in anti-TT AB titer more often when given Ent than non-Ent (33% vs. 82%) (p < 0.03). Anti-Ent AB was low and appeared unlikely to reduce Ent efficacy after repeated Ent administration. Medical safety was excellent, and a TLR5 missense polymorphism reduced anti-DPT AB production, but Ent increased anti-DPT AB titers to levels induced in subjects with genetically “normal” TRL5 functioning. Further clinical testing of TLR5 adjuvants like Ent seems warranted for anti-drug vaccines.

Polyphosphazene: A New Adjuvant Platform for Cocaine Vaccine Development

Cocaine is a highly addictive drug that has seen a steady uptrend causing severe health problems worldwide. Currently, there are no approved therapeutics for treating cocaine use disorder; hence, there is an urgent need to identify new medications. Immunopharmacotherapeutics is a promising approach utilizing endogenous antibodies generated through active vaccination, and if properly programmed, can blunt a drug's psychoactive and addictive effects. However, drug vaccine efficacy has largely been limited by the modest levels of antibodies induced. Herein, we explored an adjuvant system consisting of a polyphosphazene macromolecule, specifically poly[di(carboxylatoethylphenoxy)-phosphazene] (PCEP), a biocompatible synthetic polymer that was solicited for improved cocaine conjugate vaccine delivery performance. Our results demonstrated PCEP's superior assembling efficiency with a cocaine hapten as well as with the combined adjuvant CpG oligodeoxynucleotide (ODN). Importantly, this combination led to a higher titer response, balanced immunity, successful sequestering of cocaine in the blood, and a reduction in the drug in the brain. Moreover, a PCEP-cocaine conjugate vaccine was also found to function well via intranasal administration, where its efficacy was demonstrated through the antibody titer, affinity, mucosal IgA production, and a reduction in cocaine's locomotor activity. Overall, a comprehensive evaluation of PCEP integrated within a cocaine vaccine established an advance in the use of synthetic adjuvants in the drugs of abuse vaccine field.

Evaluating the immunogenicity of gold nanoparticles conjugated RBD with Freund's adjuvant as a potential vaccine against SARS-CoV-2

Background

and Introduction: SARS-CoV-2 is currently considered as the most challenging issue in the field of health and medicine by causing a global pandemic. Vaccines are counted as a promising candidate to terminate this deadly pandemic. Various structural proteins in SARS-CoV-2 have recently drawn attention to be utilized as candidate vaccines to stimulate immune responses against COVID-19.

Materials and methods

In current study, the RBD protein was cloned and expressed in E. coli host. Then, the expressed RBD protein was purified and its characterizations were evaluated through various methods. Gold nanoparticles, which were utilized as a carrier for candidate Nano-vaccine, were synthesized via oxidation-reduction reaction. While Gold NPs-conjugated RBD was injected into the second treatment group, in the first candidate vaccine, RBD was injected into the first treatment group solely. Complete and Incomplete Freud's Adjuvant were also utilized for both treatment groups to enhance the immune responses against RBD antigen. Immunizations were repeated 2 times in 14-day intervals to boost the immune system of BALB/c mice. The humoral and cell-mediated immune responses were examined through immune and cytokine assays.

Results

Our outcomes demonstrate that strong short-term humoral immunity (IgM) was induced in both the first and second treatment group, while long-term humoral responses (IgG) were only observed in the second treatment group. While stronger short- and long-term humoral (IgM and IgG, respectively) were observed in the second treatment group, particular cytokines production (TNF-ɑ and IFN-γ) as a marker of cell-mediated responses were significantly higher in the first treatment group.

Discussion and conclusion

Our study results show the high potentiality of RBD protein as an appropriate stimulating antigen in vaccine synthesis and testifies RBD-based candidate vaccines to control the COVID-19 pandemic. Our outcomes also recommend that Nano-vaccines can be more suitable candidates when stronger long-term immune responses matter.

Chitosan/Calcium-Coated Ginsenoside Rb1 Phosphate Flower-like Microparticles as an Adjuvant to Enhance Immune Responses

Simple Summary

The field-level control over IBD is primarily via vaccination. The development of high effective IBV vaccine has drawing great attentions worldwide. Herein, the GRb1 was encap-sulated into Calcium phosphate and chitosan core-structure nanoparticles microspheres, which con-stitute a novel system for nanoparticle delivery (GRb1/IL-4@CS/Cap). The new nano-adjuvant de-livery system could induce the activation of chicken dendritic cells ( DCs ), with up-regulate the expression of MHC II and CD80, and increase the production of IL-1β and TNF-α. At the same time, it can trigger higher levels of IBDV-specific IgG and higher IgG2a/IgG1 ratio, and promote the production of IFN-γ, TNF-α, IL-4, IL-6, IL-1α, and IL-1βand other cytokines in chicken serum after vaccination, it provides an effective adjuvant system for the development of chicken IBDV attenu-ated vaccine.

Abstract

Infectious bursal disease (IBD) is a highly contagious immunocompromising disorder that caused great economic losses in the poultry industry. The field-level control over IBD is primarily via vaccination. The development of a highly effective IBV vaccine has drawn great attention worldwide. Chitosan/Calcium Phosphate (CS/CaP) nanoparticle was a newly developed effective biological delivery system for drug and antigen. Ginsenoside Rb1 is one of the main bioactive components of ginseng root extract, which has antioxidant, anti-inflammatory and immunological enhancement effects. Until now, the combined effect of CS/CaP and ginsenoside Rb1 on the chicken immune response had remained unknown. In this study, the GRb1 and IL-4 were encapsulated into Calcium phosphate and chitosan core structure nanoparticles microspheres (GRb1/IL-4@CS/CaP), and the effect of a newly developed delivery system on an infectious bursal disease virus (IBDV) attenuated vaccine was further evaluated. The results demonstrated that GRb1/IL-4@CS/CaP treatment could induce the activation of chicken dendritic cells (DCs), with the upregulated expression of MHCII and CD80, and the increased production of IL-1β and TNF-α. Importantly, GRb1/IL-4@CS/CaP could trigger a higher level of IBDV-specific IgG and a higher ratio of IgG2a/IgG1 than the traditional adjuvant groups, promoting the production of cytokine, including IFN-γ, TNF-α, IL-4, IL-6, IL-1α, and IL-1β, in chicken serum after 28 d and 42 d post-vaccine. Taken in all, GRb1/IL-4@CS/CaP could elicit prolonged vigorous immune responses for IBDV attenuated vaccine in chicken, which might provide an effective adjuvant system for avian vaccine development.

Development of low-cost cage-like particles to formulate veterinary vaccines

Low-cost adjuvants are urgently needed for the development of veterinary vaccines able to trigger strong immune responses. In this work, we describe a method to obtain a low-cost cage-like particles (ISCOMATRIX-like) adjuvant useful to formulate veterinary vaccines candidates. The main components to form the particles are lipids and saponins, which were obtained from egg yolk by ethanolic extraction and by dialyzing a non-refined saponins extract, respectively. Lipids were fully characterized by thin layer chromatography (TLC) and gas-chromatography (GC) and enzymatic methods, and saponins were characterized by TLC, HPLC and MALDI-TOF. Cage-like particles were prepared with these components or with commercial inputs. Both particles and the traditional Alum used in veterinary vaccines were compared by immunizing mice with Ovalbumin (OVA) formulated with these adjuvants and assessing IgG1, IgG2a anti OVA antibodies and specific Delayed-type Hypersensitivity (DTH). In the yolk extract, a mixture of phospholipids, cholesterol and minor components of the extract (e.g. lyso-phospholipids) with suitable proportions to generate cage-like particles was obtained. Also, semi-purified saponins with similar features to those of the QuilA® were obtained. Cage-like particles prepared with these components have 40-50 nm and triggers similar levels of Anti-OVA IgG1 and DTH than with commercial inputs but higher specific-IgG2a. Both adjuvants largely increased the levels of IgG1, IgG2a and DTH in relation to the formulation with Alum. The methods described to extract lipids from egg yolk and saponins from non-refined extract allowed us to obtain an inexpensive and highly effective adjuvant.

Vaccines against Drug Abuse—Are We There Yet?

Background: Drug abuse is a worldwide problem that is detrimental to public health. The potential for drug abuse extends to both legal and illicit drugs. Drawbacks associated with current treatments include limited effectiveness, potential side effects and, in some instances, the absence of or concerns with approved therapy options. A significant amount of clinical research has been conducted investigating immunotherapy as a treatment option against drug abuse. Vaccines against drug abuse have been the main area of research, and are the focus of this review. Methods: An extensive search using “EBSCOhost (Multiple database collection)” with all 28 databases enabled (including “Academic Search Ultimate”, “CINAHL Plus with Full Text”, and MEDLINE), interrogation of the ClinicalTrials.gov website, and searches of individual clinical trial registration numbers, was performed in February and March of 2022. This search extended to references within the obtained articles. Results: A total of 23 registered clinical trials for treating drug abuse were identified: 15 for treatment of nicotine abuse (all vaccine-based trials), 6 against cocaine abuse (4 were vaccine-based trials and 2 were metabolic-enzyme-based trials), 1 against methamphetamine abuse (a monoclonal-antibody-based trial), and 1 multivalent opioid treatment (vaccine-based trial). As indicated on the ClinicalTrials.gov website (Home—ClinicalTrials.gov), the status of all but two of these trials was “Completed”. Phase 3 clinical trials were completed for vaccine treatments against nicotine and cocaine abuse only. Conclusion: Evidence in the form of efficacy data indicates that vaccines are not an option for treating nicotine or cocaine abuse. Efficacy data are yet to be obtained through completion of clinical trials for vaccines against opioid abuse. These findings align with the absence of regulatory approval for any of these treatments. This review further highlights the need for novel treatment strategies in instances where patients do not respond to current treatments, and while the search for efficacious vaccine-based treatments continues.

The Effect of Delivery Systems on the Induction of T Helper 1 Cell Response to an ESAT6-Like Protein Rv3619c and Identification of Its Immunodominant Peptides

OBJECTIVE

This study determined the effects of chemical adjuvants, incomplete Freund's adjuvant (IFA) and aluminum hydroxide (Alum), mycobacteria, and a DNA plasmid as delivery systems on the induction of protective Th1 (interferon-gamma (IFN-γ)) and nonprotective Th2 (IL-5) and Treg (IL-10) cytokine responses to Rv3619c and its peptides. Rv3619c is an immunodominant Mycobacterium tuberculosis-specific antigen and belongs to the early-secreted antigenic target of 6 kDa-family of proteins. Delivery systems are needed to deliver such antigens in animal models and induce protective immune responses.

METHODS

The rv3619c gene was amplified from the genomic DNA of M. tuberculosis and cloned into appropriate vectors for expression in Escherichia coli, Mycobacterium smegmatis, and eukaryotic cells. Spleen cells from mice immunized with rv3619c using different delivery systems were stimulated in vitro with synthetic peptides (P1 to P6) of Rv3619c, and secreted cytokines were estimated by ELISA.

RESULTS

The recombinant M. smegmatis and DNA plasmid induced the secretion of the protective cytokine IFN-γ in response to peptide-pool of Rv3619c and all the individual peptides, whereas rv3619c/IFA induced the secretion of IFN-γ in response to the peptide pool, and the peptides P5 and P6. However, the secretions of the nonprotective cytokines IL-5 and IL-10 were induced to none of the peptides with the delivery systems used.

CONCLUSION

Rv3619c is a major antigen of M. tuberculosis with multiple immunogenic epitopes; however, immune responses to individual epitopes can vary based on delivery systems used.

Development of effective therapeutics for polysubstance use disorders

Traditional pharmacotherapies for substance use disorders have focused on mono-substance abuse. However, recent epidemiological studies have found polysubstance use disorders (PUD) are becoming more prevalent and the abuse of adulterated drugs has led to increasing unintentional overdose deaths. Unfortunately, there are no approved pharmacological agents for PUD. Hence, a therapeutic model of interest to address this growing epidemic is immunopharmacotherapy, where individuals are inoculated with conjugate vaccines formulated with haptens that mimic the drug of abuse. These conjugate vaccines have demonstrated significant therapeutic potential against mono-substance abuse, thus recent studies have applied this model to address PUD. This review presents immunopharmacotherapeutic advancements against polysubstance abuse and discusses necessary developments for conjugate vaccines in order to effectively treat this unaddressed epidemic.

Immune to addiction: how immunotherapies can be used to combat methamphetamine addiction

Introduction: The concept of anti-methamphetamine (METH) immunotherapies is a few decades old. A substantial amount of information has been generated on the development of anti-METH immunotherapies, particularly in the preclinical stages of development of vaccines and monoclonal antibody (mAb) treatments. However, the concept of treating METH use addiction with anti-METH immunotherapies is not well understood by many researchers or general readers. A series of questions commonly arise regarding the concept: how does it work? What is the antigen used? How exactly does the vaccine prevent METH addiction?Areas covered: This paper reviews the published articles relating to the mechanisms of METH use disorders, strategies used in the development of anti-METH immunotherapies, and the mechanism of action of these treatments. It provides clear explanations to questions surrounding the basis of anti-METH immunotherapies and contextualizes their development. It also identifies areas for future investigation to speed their translation into clinical use.Expert opinion: While METH immunotherapies, including vaccines and mAbs, have progressed significantly in the last 30 years, there are newer approaches that should be evaluated to improve their translatability. Approaches including nanoparticle vaccines, virus-like particles, and other novel methods should be fully evaluated as means of generating anti-METH immunity.

Fentanyl conjugate vaccine by injected or mucosal delivery with dmLT or LTA1 adjuvants implicates IgA in protection from drug challenge

Fentanyl is a major contributor to the devastating increase in overdose deaths from substance use disorders (SUD). A vaccine targeting fentanyl could be a powerful immunotherapeutic. Here, we evaluated adjuvant and delivery strategies for conjugate antigen vaccination with fentanyl-based haptens. We tested adjuvants derived from the heat-labile toxin of E. coli including dmLT and LTA1 by intramuscular, sublingual or intranasal delivery. Our results show anti-fentanyl serum antibodies and antibody secreting cells in the bone-marrow after vaccination with highest levels observed with an adjuvant (alum, dmLT, or LTA1). Vaccine adjuvanted with LTA1 or dmLT elicited the highest levels of anti-fentanyl antibodies, whereas alum achieved highest levels against the carrier protein. Vaccination with sublingual dmLT or intranasal LTA1 provided the most robust blockade of fentanyl-induced analgesia and CNS penetration correlating strongly to anti-FEN IgA. In conclusion, this study demonstrates dmLT or LTA1 adjuvant as well as mucosal delivery may be attractive strategies for improving the efficacy of vaccines against SUD.

Immunopharmacotherapeutic advancements in addressing methamphetamine abuse

Methamphetamine (METH) is an illicit psychostimulant that is known to account for substance abuse disorders globally, second only to opioids, yet has no approved pharmacotherapies. Traditional therapies employ small molecule agonists or antagonists for substance use disorders or overdose reversal by targeting drug-specific receptors in the brain. However, the comprehensive mechanism of METH on multiple sites within the central nervous system (CNS) implies its receptors lack the high affinity and specificity required for an "ideal" drug target. The alternative to pharmacotherapies is to sequester abused drugs in the periphery, effectively eliminating the effects from CNS receptor occupation through pharmacokinetic antagonism. This review presents updates on immunopharmacotherapeutic advancements in addressing methamphetamine abuse by focusing on the cultivation of research optimization strategies regarding hapten chemistry, carrier proteins, and adjuvants implemented in active immunization. Furthermore, we discuss necessary developments for each component of active immunopharmacotherapies and the future of active vaccines in treating METH use disorder.

Biophysical characterization of polydisperse liposomal adjuvant formulations

Army Liposome Formulations (ALF) are potent adjuvants, of which there are two primary forms, lyophilized ALF (ALFlyo) containing monophosphoryl lipid A (MPLA) and ALF containing MPLA and QS21 (ALFQ). ALFlyo and ALFQ adjuvants are essential constituents of candidate vaccines for bacterial, viral, and parasitic diseases. They have been widely used in preclinical immunogenicity studies in small animals and non-human primates and are progressing to phase I/IIa clinical trials. ALFQ was prepared by adding saponin QS21 to small unilamellar liposome vesicles (SUVs) of ALF55 that contain 55 mol% cholesterol, whereas ALFlyo was created by reconstituting lyophilized SUVs of ALF43, consisting of 43 mol% cholesterol, in aqueous buffer solution. These formulations display heterogenous particle size distribution. Since biophysical characteristics of liposomes may impact their adjuvant potential, we characterized the particle size distribution and lamellarity of the individual liposome particles in ALFlyo and ALFQ formulations using cryo-electron microscopy and a newly developed MANTA technology. ALFlyo and ALFQ exhibited similar particle size distributions with liposomes ranging from 50 nm to several μm. However, fundamental differences were observed in the lamellar structures of the liposomes. ALFlyo displayed a greater number of multilamellar and multivesicular liposome particles, as compared to that in ALFQ, which was predominately unilamellar.

Modulation of immune responses using adjuvants to facilitate therapeutic vaccination

Therapeutic vaccination offers great promise as an intervention for a diversity of infectious and non-infectious conditions. Given that most chronic health conditions are thought to have an immune component, vaccination can at least in principle be proposed as a therapeutic strategy. Understanding the nature of protective immunity is of vital importance, and the progress made in recent years in defining the nature of pathological and protective immunity for a range of diseases has provided an impetus to devise strategies to promote such responses in a targeted manner. However, in many cases, limited progress has been made in clinical adoption of such approaches. This in part results from a lack of safe and effective vaccine adjuvants that can be used to promote protective immunity and/or reduce deleterious immune responses. Although somewhat simplistic, it is possible to divide therapeutic vaccine approaches into those targeting conditions where antibody responses can mediate protection and those where the principal focus is the promotion of effector and memory cellular immunity or the reduction of damaging cellular immune responses as in the case of autoimmune diseases. Clearly, in all cases of antigen-specific immunotherapy, the identification of protective antigens is a vital first step. There are many challenges to developing therapeutic vaccines beyond those associated with prophylactic diseases including the ongoing immune responses in patients, patient heterogeneity, and diversity in the type and stage of disease. If reproducible biomarkers can be defined, these could allow earlier diagnosis and intervention and likely increase therapeutic vaccine efficacy. Current immunomodulatory approaches related to adoptive cell transfers or passive antibody therapy are showing great promise, but these are outside the scope of this review which will focus on the potential for adjuvanted therapeutic active vaccination strategies.

Polymer-mediated delivery of vaccines to treat opioid use disorders and to reduce opioid-induced toxicity

Vaccines offer a potential strategy to treat opioid use disorders (OUD) and to reduce the incidence of opioid-related overdoses. Vaccines induce opioid-specific polyclonal antibodies that selectively and effectively bind the target opioid and prevent its distribution across the blood-brain barrier. Because antibody-mediated reduction of drug distribution to the brain reduces drug-induced behavior and toxicity, vaccine efficacy depends on the quantity and quality of the antibody response. This study tested whether polymer-mediated delivery could improve vaccine efficacy against opioids as well as eliminate the need for booster injections normally required for a successful immunization. A series of novel biodegradable biocompatible thermogelling pentablock co-polymers were used to formulate a candidate vaccine against oxycodone in mice and rats. Polymer-based delivery of the anti-oxycodone vaccine was equally or more effective than administration in aluminum adjuvant in generating oxycodone-specific antibodies and in reducing oxycodone-induced effects and oxycodone distribution to the brain in mice and rats. The composition and release kinetics of the polymer formulations determined vaccine efficacy. Specifically, a formulation consisting of three simultaneous injections of the anti-oxycodone vaccine formulated in three different polymers with slow, intermediate, and fast release kinetics was more effective than an immunization regimen consisting of three sequential injections with the vaccine adsorbed on aluminum. The novel three-phased polymer vaccine formulation was effective in blocking oxycodone-induced antinociception, respiratory depression and bradycardia in rats.

The structural characterization and immune modulation activitives comparison of Codonopsis pilosula polysaccharide (CPPS) and selenizing CPPS (sCPPS) on mouse in vitro and vivo

Codonopsis pilosula polysaccharide (CPPS) and selenizing CPPS (sCPPS) were prepared and identified by a combination of chemical and instrumental analysis. Their immune modulation activities were compared by lymphocyte proliferation and flowcytometry tests in vitro or serum antibody responses and cytokines with immunization against OVA mice in vivo. The results showed that the sCPPS was successfully modified in selenylation. In vitro, the sCPPS were more effective compared with CPPS in promoting lymphocyte proliferation synergistically with PHA or LPS and increasing the ratio of CD4+ to CD8 + T cells. In vivo, sCPPS could significantly raised IgG, IgM, IFN-γ, IL-2 and IL-4 contents in the serum of mouse against OVA in comparison with CPPS. These results indicate that selenylation modification can enhance the immune modulation activitives of CPPS. sCPPS would be as a component drug of new-type immunoenhancer.

Army Liposome Formulation (ALF) family of vaccine adjuvants

Introduction: 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. For protection of personnel against difficult disease threats found in many areas of the world, Army vaccine scientists have created novel liposome-based vaccine adjuvants.Areas covered: ALF consists of liposomes containing saturated phospholipids, cholesterol, and monophosphoryl lipid A (MPLA) as an immunostimulant. ALF exhibited safety and strong potency in many vaccine clinical trials. Improvements based on ALF include: ALF adsorbed to aluminum hydroxide (ALFA); ALF containing QS21 saponin (ALFQ); and ALFQ adsorbed to aluminum hydroxide (ALFQA). Preclinical safety and efficacy studies with ALF, LFA, ALFQ, and ALFQA are discussed in preparation for upcoming vaccine trials targeting malaria, HIV-1, bacterial diarrhea, and opioid addiction.Expert opinion: The introduction of ALF in the 1980s stimulated commercial interest in vaccines to infectious diseases, and therapeutic vaccines to cancer, and Alzheimer's disease. It is likely that ALF, ALFA, and ALFQ, will provide momentum for new types of modern vaccines with improved efficacy and safety.

The effect of adjuvants and delivery systems on Th1, Th2, Th17 and Treg cytokine responses in mice immunized with Mycobacterium tuberculosis-specific proteins

Tuberculosis (TB) is a major health problem of global concern. The control of this disease requires appropriate preventive measures, including vaccines. In TB, T helper (Th)1 cytokines provide protection whereas Th2 and T regulatory (Treg) cytokines contribute to the pathogenesis and Th17 cytokines play a role in both protection and pathogenesis. Previous studies with Mycobacterium tuberculosis-specific proteins have identified seven low molecular weight proteins, PE35, ESXA, ESXB, Rv2346c, Rv2347c, Rv3619c, and Rv3620c, as immunodominant antigens inducing Th1-cell responses in humans following natural infection with M. tuberculosis. The aim of this study was to characterize the cytokine responses induced in mice immunized with these proteins, using various adjuvants and delivery systems, i.e. chemical adjuvants (Alum and IFA), non-pathogenic mycobacteria (M. smegmatis and M. vaccae) and a DNA vaccine plasmid (pUMVC6). The immune responses were monitored by quantifying the marker cytokines secreted by Th1 (IFN-ɣ), Th2 (IL-5), Treg (IL-10), and Th17 (IL-17A) cells. DNA corresponding to pe35, esxa, esxb, rv2346c, rv2347c, rv3619c, and rv3620c genes were cloned into the expression vectors pGES-TH-1, pDE22 and pUMVC6 for expression in Escherichia coli, mycobacteria and eukaryotic cells, respectively. Mice were immunized with the recombinants using different adjuvants and delivery systems, and spleen cells were stimulated in vitro with peptides of immunizing proteins to investigate antigen-specific secretion of Th1 (IFN-ɣ), Th2 (IL-5), Treg (IL-10), and Th17 (IL-17A) cytokines. The results showed that spleen cells, from mice immunized with all antigens, secreted the protective Th1 cytokine IFN-ɣ, except ESXB, with one or more adjuvants and delivery systems. However, only Rv3619c consistently induced Th1-biased responses, without the secretion of significant concentrations of Th2, Th17 and Treg cytokines, with all adjuvants and delivery systems. Rv3619c also induced antigen-specific IgG antibodies in immunized mice.

Personalized neoantigen-pulsed dendritic cell vaccines show superior immunogenicity to neoantigen-adjuvant vaccines in mouse tumor models

Development of personalized cancer vaccines based on neoantigens has become a new direction in cancer immunotherapy. Two forms of cancer vaccines have been widely studied: tumor-associated antigen (including proteins, peptides, or tumor lysates)-pulsed dendritic cell (DC) vaccines and protein- or peptide-adjuvant vaccines. However, different immune modalities may produce different therapeutic effects and immune responses when the same antigen is used. Therefore, it is necessary to choose a more effective neoantigen vaccination method. In this study, we compared the differences in immune and anti-tumor effects between neoantigen-pulsed DC vaccines and neoantigen-adjuvant vaccines using murine lung carcinoma (LL2) candidate neoantigens. The enzyme-linked immunospot (ELISPOT) assay showed that 4/6 of the neoantigen-adjuvant vaccines and 6/6 of the neoantigen-pulsed DC vaccines induced strong T-cell immune responses. Also, 2/6 of the neoantigen-adjuvant vaccines and 5/6 of the neoantigen-pulsed DC vaccines exhibited potent anti-tumor effects. The results indicated that the neoantigen-pulsed DC vaccines were superior to the neoantigen-adjuvant vaccines in both activating immune responses and inhibiting tumor growth. Our fundings provide an experimental basis for the selection of immune modalities for the use of neoantigens in individualized tumor immunotherapies.

Development of vaccines to treat opioid use disorders and reduce incidence of overdose

Vaccines offer a promising therapeutic strategy to treat substance use disorders (SUD). Vaccines have shown extensive preclinical proof of selectivity, safety, and efficacy against opioids, nicotine, cocaine, methamphetamine, and designer drugs. Despite clinical evaluation of vaccines targeting nicotine and cocaine showing proof of concept for this approach, no vaccine for SUD has yet reached the market. This review first discusses how vaccines for treatment of opioid use disorders (OUD) and reduction of opioid-induced fatal overdoses fit within the current medication assisted treatment (MAT) portfolio, and then summarizes ongoing efforts toward translation of vaccines targeting heroin, oxycodone, fentanyl, and other opioids. This article is part of the Special Issue entitled 'New Vistas in Opioid Pharmacology'.

Citrulline as a novel adjuvant candidate for vaccines

For a long time, many types of vaccines have been useful for the prophylaxis of many infectious diseases. Thus far, many adjuvants that enhance the effects of vaccines have been explored. However, very few adjuvants are being used for humans worldwide. In this study, we investigated the adjuvant activity of various substances, and found citrulline to have high potential as an adjuvant. Citrulline is a type of amino acid present in the body of many organisms. A number of biological activities of citrulline have been reported; however, no adjuvant activity has been reported thus far. Aluminum salts, which are commonly used as adjuvants are not water soluble; therefore, some difficulties are encountered while using them as vaccine adjuvants. Citrulline is easy to use because of its water solubility. In this study, we showed for the first time the adjuvant activity of citrulline by using viral antigens and amyloid β peptide. Water-soluble citrulline, which is present in our body, is a potential adjuvant candidate.

Effect of Adjuvant Release Rate on the Immunogenicity of Nanoparticle-Based Vaccines: A Case Study with a Nanoparticle-Based Nicotine Vaccine

Adjuvants are a critical component for vaccines, especially for a poorly immunogenic antigen, such as nicotine. However, the impact of adjuvant release rate from a vaccine formulation on its immunogenicity has not been well illustrated. In this study, we fabricated a series of hybrid-nanoparticle-based nicotine vaccines to study the impact of adjuvant release rate on their immunological efficacy. It was found that the nanovaccine with a medium or slow adjuvant release rate induced a significantly higher anti-nicotine antibody titer than that with a fast release rate. Furthermore, the medium and slow adjuvant release rates resulted in a significantly lower brain nicotine concentration than the fast release rate after nicotine challenge. All findings suggest that adjuvant release rate affects the immunological efficacy of nanoparticle-based nicotine vaccines, providing a potential strategy to rationally designing vaccine formulations against psychoactive drugs or even other antigens. The hybrid-nanoparticle-based nicotine vaccine with an optimized adjuvant release rate can be a promising next-generation immunotherapeutic candidate against nicotine.

Chemical and Immunological Characteristics of Aluminum-Based, Oil-Water Emulsion, and Bacterial-Origin Adjuvants

Adjuvants are a diverse family of substances whose main objective is to increase the strength, quality, and duration of the immune response caused by vaccines. The most commonly used adjuvants are aluminum-based, oil-water emulsion, and bacterial-origin adjuvants. In this paper, we will discuss how the election of adjuvants is important for the adjuvant-mediated induction of immunity for different types of vaccines. Aluminum-based adjuvants are the most commonly used, the safest, and have the best efficacy, due to the triggering of a strong humoral response, albeit generating a weak induction of cell-mediated immune response. Freund's adjuvant is the most widely used oil-water emulsion adjuvant in animal trials; it stimulates inflammation and causes aggregation and precipitation of soluble protein antigens that facilitate the uptake by antigen-presenting cells (APCs). Adjuvants of bacterial origin, such as flagellin, E. coli membranes, and monophosphoryl lipid A (MLA), are known to potentiate immune responses, but their safety and risks are the main concern of their clinical use. This minireview summarizes the mechanisms that classic and novel adjuvants produce to stimulate immune responses.

Identification of Immune Signatures of Novel Adjuvant Formulations Using Machine Learning

Adjuvants have long been critical components of vaccines, but the exact mechanisms of their action and precisely how they alter or enhance vaccine-induced immune responses are often unclear. In this study, we used broad immunoprofiling of antibody, cellular, and cytokine responses, combined with data integration and machine learning to gain insight into the impact of different adjuvant formulations on vaccine-induced immune responses. A Self-Assembling Protein Nanoparticles (SAPN) presenting the malarial circumsporozoite protein (CSP) was used as a model vaccine, adjuvanted with three different liposomal formulations: liposome plus Alum (ALFA), liposome plus QS21 (ALFQ), and both (ALFQA). Using a computational approach to integrate the immunoprofiling data, we identified distinct vaccine-induced immune responses and developed a multivariate model that could predict the adjuvant condition from immune response data alone with 92% accuracy (p = 0.003). The data integration also revealed that commonly used readouts (i.e. serology, frequency of T cells producing IFN-γ, IL2, TNFα) missed important differences between adjuvants. In summary, broad immune-profiling in combination with machine learning methods enabled the reliable and clear definition of immune signatures for different adjuvant formulations, providing a means for quantitatively characterizing the complex roles that adjuvants can play in vaccine-induced immunity. The approach described here provides a powerful tool for identifying potential immune correlates of protection, a prerequisite for the rational pairing of vaccines candidates and adjuvants.

Novel technologies in detection, treatment and prevention of substance use disorders

Substance use disorders are a widely recognized problem, which affects various levels of communities and influenced the world socioeconomically. Its source is deeply embedded in the global population. In order to fight against such an adversary, governments have spared no efforts in implementing substance abuse treatment centers and funding research to develop treatments and prevention procedures. In this review, we will discuss the use of immunological-based treatments and detection kit technologies. We will be detailing the steps followed to produce performant antibodies (antigens, carriers, and adjuvants) focusing on cocaine and methamphetamine as examples. Furthermore, part of this review is dedicated to substance use detection. Owing to novel technologies such as bio-functional polymeric surfaces and biosensors manufacturing, detection has become a more convenient method with the fast and on-site developed devices. Commercially available devices are able to test substance use disorders in urine, saliva, hair, and sweat. This improvement has had a tremendous impact on the prevention of driving under influence and other illicit behaviors. Lastly, substance abuse became a major issue involving the cooperation of experts on all levels to devise better treatment programs and prevent abuse-based accidents, injury and death.

Ethical Implications in Vaccine Pharmacotherapy for Treatment and Prevention of Drug of Abuse Dependence

Different immunotherapeutic approaches are in the pipeline for the treatment of drug dependence. "Drug vaccines" aim to induce the immune system to produce antibodies that bind to drugs and prevent them from inducing rewarding effects in the brain. Drugs of abuse currently being tested using these new approaches are opioids, nicotine, cocaine, and methamphetamine. In human clinical trials, "cocaine and nicotine vaccines" have been shown to induce sufficient antibody levels while producing few side effects. Studies in humans, determining how these vaccines interact in combination with their target drug, are underway. However, although vaccines can become a reasonable treatment option for drugs of abuse, there are several disadvantages that must be considered. These include i) great individual variability in the formation of antibodies, ii) the lack of protection against a structurally dissimilar drug that produces the same effects as the drug of choice, and iii) the lack of an effect on the drug desire that may predispose an addict to relapse. In addition, a comprehensive overview of several crucial ethical issues has not yet been widely discussed in order to have not only a biological approach to immunotherapy of addiction. Overall, immunotherapy offers a range of possible treatment options: the pharmacological treatment of addiction, the treatment of overdoses, the prevention of toxicity to the brain or the heart, and the protection of the fetus during pregnancy. So far, the results obtained from a small-scale experiment using vaccines against cocaine and nicotine suggest that a number of important technical challenges still need to be overcome before such vaccines can be approved for clinical use.

Current status of vaccines in psychiatry-A narrative review

INTRODUCTION

Vaccines are one of the newer therapeutic modalities being researched in psychiatric illnesses with limited role of pharmacological interventions. Preclinical studies on vaccines have shown favorable results in conditions like Substance use Disorders and Alzheimer's Dementia. However, the utility of Mumps Measles Rubella vaccine has been overshadowed by controversy linked to causation of Autism. With this background, the current narrative review aimed to comprehensively and critically evaluate the current status of vaccines in Psychiatric illnesses.

METHODS

Preliminary literature search using the electronic databases of MEDLINE and Google Scholar between May 1967 and May 2017 using the search terms "Vaccines" and "Psychiatry" was carried out and articles were found in the following areas of research: Substance use, Alzheimer Dementia, Autism, Human Immunodeficiency Virus and Human Papilloma Virus Further, the refined search was done using combinations of search terms "Vaccine", "Nicotine", "Cocaine", "Opioid", "Alzheimer Dementia", "Autism", and "Pervasive Developmental Disorders" and peer - reviewed original articles published in English conducted among human subjects and published in English language were included for review.

RESULTS

A total of 31 articles found eligible were organized into appropriate sections synthesizing the literature on role of vaccines in specific disorders such as Substance Use Disorders, Alzheimer Dementia and Pervasive Developmental Disorders.

DISCUSSION

The therapeutic potential of vaccines in Substance Use Disorders and Alzheimer Dementia was found to be limited in comparison to the results from animal studies. Safety profile of the immunogens and the adjuvants in humans is possibly the most important limitation. No causal association between Measles Mumps Rubella vaccine and Autism was found.

A Stable Heroin Analogue That Can Serve as a Vaccine Hapten to Induce Antibodies That Block the Effects of Heroin and Its Metabolites in Rodents and That Cross-React Immunologically with Related Drugs of Abuse

An 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. Using the Boc protectng group in 18 allowed preparation of 1 in an overall yield of 53% from 4 and eliminated the necessity of preparing the diamide 13. Hapten 1 was conjugated to tetanus toxoid and mixed with liposomes containing monophosphoryl lipid A as an adjuvant. The 1 vaccine induced high anti-1 IgG levels that reduced heroin-induced antinociception and locomotive behavioral changes following repeated subcutaneous and intravenous heroin challenges in mice and rats. Vaccinated mice had reduced heroin-induced hyperlocomotion following a 50 mg/kg heroin challenge. The 1 vaccine-induced antibodies bound to heroin and other abused opioids, including hydrocodone, oxycodone, hydromorphone, oxymorphone, and codeine.

Rational incorporation of molecular adjuvants into a hybrid nanoparticle-based nicotine vaccine for immunotherapy against nicotine addiction

Current clinically-tested nicotine vaccines have yet shown enhanced smoking cessation efficacy due to their low immunogenicity. Achieving a sufficiently high immunogenicity is a necessity for establishing a clinically-viable nicotine vaccine. This study aims to facilitate the immunogenicity of a hybrid nanoparticle-based nicotine vaccine by rationally incorporating toll-like receptor (TLR)-based adjuvants, including monophosphoryl lipid A (MPLA), Resiquimod (R848), CpG oligodeoxynucleotide 1826 (CpG ODN 1826), and their combinations. The nanoparticle-delivered model adjuvant was found to be taken up more efficiently by dendritic cells than the free counterpart. Nanovaccine particles were transported to endosomal compartments upon cellular internalization. The incorporation of single or dual TLR adjuvants not only considerably increased total anti-nicotine IgG titers but also significantly affected IgG subtype distribution in mice. Particularly, the nanovaccines carrying MPLA+R848 or MPLA+ODN 1826 generated a much higher anti-nicotine antibody titer than those carrying none or one adjuvant. Meanwhile, the anti-nicotine antibody elicited by the nanovaccine adjuvanted with MPLA+R848 had a significantly higher affinity than that elicited by the nanovaccine carrying MPLA+ODN 1826. Moreover, the incorporation of all the selected TLR adjuvants (except MPLA) reduced the brain nicotine levels in mice after nicotine challenge. Particularly, the nanovaccine with MPLA+R848 exhibited the best ability to reduce the level of nicotine entering the brain. Collectively, rational incorporation of TLR adjuvants could enhance the immunological efficacy of the hybrid nanoparticle-based nicotine vaccine, making it a promising next-generation immunotherapeutic candidate for treating nicotine addiction.

Heroin-HIV-1 (H2) vaccine: induction of dual immunologic effects with a heroin hapten-conjugate and an HIV-1 envelope V2 peptide with liposomal lipid A as an adjuvant

A 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. Upon immunization of mice, palm-cyclic peptide induced anti-cyclic peptide endpoint titers >10⁶ and was considered to be a better immunogen overall than palm-linear V2 peptide for inducing antibodies to gp120 and gp70-V1V2. The antibodies also inhibited the binding of V2 peptide to the HIV-1 α₄β₇ integrin receptor. Antibody titers to MorHap, even with the presence of injected cyclic peptide, were very high, and resulted in inhibition of the hyper-locomotion and antinociception effects of injected heroin. From these initial experiments, we conclude that with a potent adjuvant and mostly synthetic constituents, a vaccine directed to heroin and HIV-1 (H2 vaccine) could be a feasible objective.

A vaccine designed to treat heroin addiction while at the same time preventing HIV infection elicited strong immune responses in mice. Scientists from the US government led by Carl Alving from the Walter Reed Army Institute of Research in Bethesda, Maryland, created a dual vaccine formulated with three main components: a segment of a protein expressed on the surface of HIV; synthetic molecules that resemble heroin and its degradation products; and a potent adjuvant to stimulate the immune system. Mice immunized with this vaccine had high antibody titers against the HIV surface protein as well as heroin and its derivatives. These mice also showed dulled responses to injected heroin. The findings suggest this vaccine strategy could help fight heroin abuse and the high risk of HIV infection among intravenous drug users.

Are therapeutic vaccines an answer to the global problem of drug and alcohol abuse?

Drug Abuse has become a major challenging problem for the society. It effects people of all countries economical strata's and all ages. According. Monetary loss all over the world regarding drug abuse is in million dollars, it not only has an impact on human productivity and healthcare cost but also on cost of crimes conducted by these drugs and alcohol abuse. Therapeutic vaccine has come as new approach to deal with this problem, after failures in search for a pharmaceutical agent to deal with drug of abuse and alcohol. Research in field of nicotine abuse has gone a way ahead with number of vaccines being tried clinically followed by cocaine, opioids, methamphetamine, phencyclidine and alcohol. All of them have a common mechanism of action by antibody production whereas alcohol acts by genetic intervention. None have being approved yet due to poor results in phase II trials, possibly due to not able to trigger an adequate immunological response. But still quest is on for cracking the ice by developing first successful vaccine against drug of abuse, that would follow for other drugs too. It would be great step in field of therapeutic vaccines for drug abuse after similar successful vaccines being approved for other diseases like cancer.

Evaluating the immunogenicity of an intranasal vaccine against nicotine in mice using the Adjuvant Finlay Proteoliposome (AFPL1)

Tobacco smoking is recognized as a global pandemic resulting in 6 million deaths per year. Despite a variety of anti-smoking products available to aid with tobacco cessation, the majority of people who attempt to quit smoking relapse within 6 months due to the addictive nature of nicotine. An immunotherapy approach could offer a promising treatment option by inducing a potent selective antibody response against nicotine in order to block its distribution to the brain and its addictive effects in the central nervous system. Our nicotine vaccine candidate was administered intranasally using the Neisseria meningitidis serogroup B Adjuvant Finlay Proteoliposome 1 (AFPL1) as a part of the delivery system. This system was designed to generate a robust immune response by stimulating IL-1β production through Toll-like receptor 4 (TLR4), a potent mechanism for mucosal immunity. The vaccine induced high antibody titers in mice sera in addition to inducing mucosal antibodies. The efficacy of our vaccine was demonstrated using in vivo challenge experiments with radioactive [³H]-nicotine, followed by an analysis of nicotine distribution in the lung, liver, blood and brain. Our results were encouraging as the nicotine concentration in the brain tissue of mice vaccinated with our candidate vaccine was four times lower than in non-vaccinated controls; suggesting that the anti-nicotine antibodies were able to block nicotine from crossing the blood brain barrier. In summary, we have developed a novel nicotine vaccine for the treatment of tobacco addiction by intranasal administration and also demonstrated that the AFPL1 can be used as a potential adjuvant for this vaccine design.

Role of nanotechnology in HIV/AIDS vaccine development

HIV/AIDS is one of the worst crises affecting global health and influencing economic development and social stability. Preventing and treating HIV infection is a crucial task. However, there is still no effective HIV vaccine for clinical application. Nanotechnology has the potential to solve the problems associated with traditional HIV vaccines. At present, various nano-architectures and nanomaterials can function as potential HIV vaccine carriers or adjuvants, including inorganic nanomaterials, liposomes, micelles and polymer nanomaterials. In this review, we summarize the current progress in the use of nanotechnology for the development of an HIV/AIDS vaccine and discuss its potential to greatly improve the solubility, permeability, stability and pharmacokinetics of HIV vaccines. Although nanotechnology holds great promise for applications in HIV/AIDS vaccines, there are still many inadequacies that result in a variety of risks and challenges. The potential hazards to the human body and environment associated with some nano-carriers, and their underlying mechanisms require in-depth study. Non-toxic or low-toxic nanomaterials with adjuvant activity have been identified. However, studying the confluence of factors that affect the adjuvant activity of nanomaterials may be more important for the optimization of the dosage and immunization strategy and investigations into the exact mechanism of action. Moreover, there are no uniform standards for investigations of nanomaterials as potential vaccine adjuvants. These limitations make it harder to analyze and deduce rules from the existing data. Developing vaccine nano-carriers or adjuvants with high benefit-cost ratios is important to ensure their broad usage. Despite some shortcomings, nanomaterials have great potential and application prospects in the fields of AIDS treatment and prevention.

Biologics to treat substance use disorders: Current status and new directions

Biologics (vaccines, monoclonal antibodies (mAb), and genetically modified enzymes) offer a promising class of therapeutics to treat substance use disorders (SUD) involving abuse of opioids and stimulants such as nicotine, cocaine, and methamphetamine. In contrast to small molecule medications targeting brain receptors, biologics for SUD are larger molecules that do not cross the blood-brain barrier (BBB), but target the drug itself, preventing its distribution to the brain and blunting its effects on the central nervous system (CNS). Active and passive immunization approaches rely on antibodies (Ab) that bind drugs of abuse in serum and block their distribution to the brain, preventing the rewarding effects of drugs and addiction-related behaviors. Alternatives to vaccines and anti-drug mAb are genetically engineered human or bacterial enzymes that metabolize drugs of abuse, lowering the concentration of free active drug. Pre-clinical and clinical data support development of effective biologics for SUD.

Suppression of Cocaine-Evoked Hyperactivity by Self-Adjuvanting and Multivalent Peptide Nanofiber Vaccines

The development of anti-cocaine vaccines that counteract the rewarding effects of the drug are currently being investigated as adjunct therapies for prevention of relapse in abstinent users. However, cocaine is weakly immunogenic and requires conjugation to carrier proteins and coadministration with strong adjuvants, which carry the risk of local reactogenicity and systemic toxicity. Here we report synthetic and multivalent self-assembling peptide nanofibers as adjuvant-free carriers for cocaine vaccines. A novel cocaine hapten modified at the P3 site was conjugated to the N-terminus of an amphipathic self-assembling domain KFE8. In aqueous buffers the cocaine-KFE8 conjugate assembled into β-sheet rich nanofibers, which raised anti-cocaine antibodies without the need for added adjuvants in mice. Vaccinated mice were treated with cocaine and a significant negative correlation was observed between antibody levels and cocaine-evoked hyperactivity. These totally synthetic and multivalent nanofibers with well-defined chemical composition represent the first generation of adjuvant-free cocaine vaccines.

Evaluation of a water-soluble adjuvant for the development of monoclonal antibodies against small-molecule compounds*

A water-soluble adjuvant named QuickAntibody (QA) was introduced into the procedure of mouse immunization for the development of hapten-specific monoclonal antibodies (mAbs), using four kinds of pesticides as model compounds. Compared with conventional Freund’s adjuvants, QA treatments offered relatively low but acceptable antiserum titers after three inoculations, gave little adverse effects to the experimental animals, and were preferable in harvesting splenocytes during the steps of cell fusion. Afterwards, hybridomas from the QA group were prepared and screened by both non-competitive and competitive indirect enzyme-linked immunosorbent assays (ELISAs). The efficiency of gaining immune-positive hybridomas was satisfactory, and the resultant mAbs showed sensitivities (half maximal inhibitory concentration (IC50)) of 0.91, 2.46, 3.72, and 6.22 ng/ml to triazophos, parathion, chlorpyrifos, and fenpropathrin, respectively. Additionally, the performance of QA adjuvant was further confirmed by acquiring a high-affinity mAb against okadaic acid (IC50 of 0.36 ng/ml) after three immunizations. These newly developed mAbs showed similar or even better sensitivities compared with previously reported mAbs specific to the corresponding analytes. This study suggested that the easy-to-use adjuvant could be applicable to the efficient generation of highly sensitive mAbs against small compounds.