Antibody Gene Therapy Mitigates Adverse Immunological Effects of 3,4‐Methylenedioxymethamphetamine (MDMA) in Male BALB/c Mice
Authors: Bolden Chris , Tilley Cameron , Hay Charles E. , Peterson Eric 
Published: April 2020

3,4‐Methylenedioxymethamphetamine (MDMA) is a popular recreational psychostimulant and hallucinogen typically used in “rave” settings. Despite the “positive” feelings sometimes associated with its use, there are toxicities that accompany its use. In the periphery, MDMA causes immunosuppression that can make users more susceptible to infection. Conversely, in the CNS MDMA initiates a proinflammatory response that is linked to glial activation and the subsequent overproduction of cytokines, chemokines, and even cellular adhesion molecules. A treatment that could potentially mitigate these effects would be beneficial.In our laboratory, we are developing an anti‐MDMA/methamphetamine (METH) dual‐acting antibody gene therapy as a treatment for substance use disorders (SUD). Utilizing the adeno‐associated virus AAV8 as our gene therapy vector, we packaged the single chain‐Fc fusion fragment 7F9‐Fc to create AAV‐7F9‐Fc. AAV‐7F9‐Fc expresses anti‐MDMA/METH antibodies systemically that work as pharmacokinetic antagonists to slow and possibly reduce entry of drug into the brain and other organs. AAV‐7F9‐Fc produces effective long‐term serum concentrations of antibodies in mice (>7 months from a single dose) and has been shown to alter METH‐induced locomotor effects in mice. Because of the chemical backbone similarity between METH and MDMA, we hypothesized that AAV‐7F9‐Fc would also be able to bind to MDMA in serum and reduce the immunomodulatory effects induced by MDMA. If proven effective, this treatment could provide some protection against the toxic effects of METH and MDMA during recovery.We hypothesized that an AAV delivered antibody fusion fragment (AAV‐7F9‐Fc) will provide extended protection from MDMA‐induced neuroinflammation and systemic immune suppression. To begin to test this hypothesis, we are evaluating an acute mouse model of MDMA use. Drug administration followed a binge dosing regimen of an ip injection every 2 hr for 4 consecutive doses. After the MDMA dosing regimen, we measured serum cytokine levels by multiplex analysis, and CNS proinflammatory cytokine and glial cell activation markers by qRT‐PCR. BALB/c mice were divided into nine groups (n=5/group); 1) Saline + Saline, 2) Saline + MDMA (10 mg/kg 2hr × 4), 3) Saline + MDMA (3 mg/kg 2hr × 4), 4) Saline + MDMA (1 mg/kg 2hr × 4) 5) LPS, 6) AAV‐7F9‐Fc + Saline, 7) AAV‐7F9‐Fc + MDMA (10 mg/kg 2hr × 4), 8) Empty Vector + saline & 9) Empty Vector + MDMA (10 mg/kg 2hr × 4). Our results indicate significant decreases (p< 0.05) in the serum concentration of proinflammatory cytokine IL‐1β & IFN‐γ and increases in the anti‐inflammatory cytokine IL‐10 (p< 0.05) in response to the 10 mg/kg MDMA dose. In the striatum, 10 mg/kg MDMA elicited a significant increase in expression of IL‐1β and astrocyte activation marker GFAP. AAV‐7F9‐Fc treatment mitigated the increase of IL‐10 in the serum and IL‐1β in the striatum. These results indicate that in addition to its previously reported protection against METH, AAV‐7F9‐Fc can mitigate an immunomodulatory cascade in the periphery and CNS resulting from MDMA exposure.Support or Funding InformationThis research was funded by NIH/NIDA:R01‐DA036600 & R01 DA036600‐03S1, NIH/NIGMS:T32‐GM106999, and R25GM083297.