Alum adjuvant is more effective than MF59 at prompting early germinal center formation in response to peptide-protein conjugates and enhancing efficacy of a vaccine against opioid use disorders

Abstract

Opioid use disorders (OUD) and fatal overdoses are a national emergency in the United States. Therapeutic vaccines offer a promising strategy to treat OUD and reduce the incidence of overdose. Immunization with opioid-based haptens conjugated to immunogenic carriers elicits opioid-specific antibodies that block opioid distribution to the brain and reduce opioid-induced behavior and toxicity in pre-clinical models. This study tested whether the efficacy of a lead oxycodone conjugate vaccine was improved by formulation in either aluminum hydroxide or the squalene-based oil-in-water emulsion MF59 adjuvant, which was recently FDA-approved for influenza vaccines in subjects 65 + years old. In adult BALB/c mice, alum formulation was more effective than MF59 at promoting the early expansion of hapten-specific B cells and the production of oxycodone-specific serum IgG antibodies, as well as blocking oxycodone distribution to the brain and oxycodone-induced motor activity. Alum was also more effective than MF59 at promoting early differentiation of peptide-specific MHCII-restricted CD4 + Tfh and GC-Tfh cells in adult C57Bl/6 mice immunized with a model peptide-protein conjugate. In contrast, alum and MF59 were equally effective in promoting hapten-specific B cells and peptide-specific MHCII-restricted CD4 + T cell differentiation in older C57Bl/6 mice. These data suggest that alum is a more effective adjuvant than MF59 for conjugate vaccines targeting synthetic small molecule haptens or peptide antigens in adult, but not aged, mice. ARTICLE HISTORY

Mechanisms of interleukin 4 mediated increase in efficacy of vaccines against opioid use disorders

“…Previous studies have shown that the efficacy of anti-opioid vaccines could be increased by traditional adjuvant platforms, including TLR3, TLR4, TLR5, and TLR9 agonists, oil-in-water emulsions, aluminum salts, and squalene emulsions [31][32][33][34]59 . Using a previously established molecular adjuvant strategy focused on modulating the adaptive immune response 40 , this study demonstrated that αIL-4 increases efficacy of several anti-opioid vaccine formulations, suggesting that immunomodulation of IL-4 may be broadly applicable to other vaccines targeting small molecules, peptides, or purified protein subunits.…”

“…In this context, B and T cell responses to vaccines can be shaped by the incorporation of adjuvants to achieve successful immunization 29,30 . Pre-clinical studies have already shown that the efficacy of vaccines against SUD is enhanced by adjuvants such as aluminum salts (alum) and toll-like receptor 4 (TLR4) or TLR9 agonists [31][32][33][34] . In contrast to more traditional adjuvants, this study focuses on the use of cytokine-targeting immunomodulators as a strategy to enhance GC formation and to increase vaccine efficacy against drugs of abuse.…”

Combining a Candidate Vaccine for Opioid Use Disorders with Extended-Release Naltrexone Increases Protection against Oxycodone-Induced Behavioral Effects and Toxicity

“…Drug-induced motor activity has been previously used as a means of screening vaccination efficacy against opioids and other drugs of abuse (Carrera et al, 2001;Cornish et al, 2011;Li et al, 2011;Wee et al, 2012;Raleigh et al, 2013;Robinson et al, 2019). Fewer studies have characterized oxycodoneinduced motor activity (Leri and Burns, 2005;Niikura et al, 2013) or tested the preclinical efficacy of XR-NTX in preventing oxycodone-induced behaviors (Bartus et al, 2003;Dean et al, 2008).…”

“…Active immunization with opioid-based conjugate vaccines elicits antibodies that selectively bind the target opioid in serum and extracellular fluids and effectively reduce opioid distribution to brain, ultimately blunting opioid-induced behavior and toxicity (Bonese et al, 1974;Anton and Leff, 2006;Stowe et al, 2011;Pravetoni et al, 2012b). Conjugation of an oxycodone (OXY)-based hapten to native or good manufacturing practice-grade subunit keyhole limpet hemocyanin (KLH) carrier protein generated a vaccine (OXY-KLH) that reduced the distribution of oxycodone and hydrocodone to brain and their subsequent behavioral effects in mice and rats, including acquisition of oxycodone self-administration and oxycodone-induced gene expression in the midbrain (Pravetoni et al, 2013(Pravetoni et al, , 2014aRaleigh et al, 2017;Robinson et al, 2019). Similarly, an analogous oxycodone vaccine reduced maintenance of oxycodone intravenous self-administration (Nguyen et al, 2018).…”

Monoclonal Antibodies Counteract Opioid-Induced Behavioral and Toxic Effects in Mice and Rats

“…Table 1), and pooled lymph nodes and spleens were collected 4 days after the second immunization. The antigen-based magnetic enrichment procedure to isolate opioid-specific B cells was performed as described in (Robinson et al, 2019). Briefly, tissues were processed to a single-cell suspension, and cells were pelleted at 1600 rpm for 5 min.…”