BACKGROUND Cannabidiol (CBD) is increasingly used for pain management, including in transplant recipients with limited analgesic options. Its immunomodulatory effects in humans are not well defined at a single-cell level at CBD steady state with concomitant tacrolimus treatment.METHODS In a phase I ex vivo study, peripheral blood mononuclear cells from 23 participants who received oral CBD (Epidiolex) up to 5 mg/kg twice daily for 11 days were collected before CBD (pre-CBD) and at steady state (post-CBD). Lymphocytes were isolated and stimulated with anti-CD3/CD28 antibodies, with or without tacrolimus (5 ng/mL). Pharmacodynamic responses were assessed using CellTiter-Glo proliferation, single-cell and single-nucleus RNA sequencing, cytokine assays, and flow cytometry. Steady-state plasma concentrations of CBD were quantified via tandem mass spectrometry.RESULTS We identified an increased proportion of T effector memory (TEM) cells post-CBD (22% increase), which correlated with CBD plasma concentrations (R = 0.77, P = 0.01). CBD reduced proliferation of T (37% decrease) and CD70hi B (17% decrease) lymphocytes with additive immunosuppressive effects to tacrolimus. Single-cell RNA sequencing revealed reduced IL2 and TNF signaling and altered receptor-ligand networks in TEM cells. Post-CBD cytokine assays revealed elevated proinflammatory IL-6 protein levels and antiinflammatory IL-10 levels, with reduced TNF-α, LTA, and IL-2. In flow cytometry, the proportion of TEM and TEMRA cells increased post-CBD with tacrolimus.CONCLUSION CBD exerts mixed immunomodulatory effects in humans, combining antiproliferative and pro- and antiinflammatory responses. Understanding the clinical safety of CBD use is important given the paucity of pain control options available for immunocompromised transplant populations.TRIAL REGISTRATION ClinicalTrials.gov NCT05490511FUNDING NIH/National Center for Complementary and Integrative Health (R01AT011463); NIH/National Institute of General Medical Sciences (NIGMS) (R35GM145383); Intramural Research Program of the NIH; NIH/NIGMS (T32GM008425).
Debora L. Gisch, Sachiko Koyama, Jumar Etkins, Gerald C. So, Daniel J. Fehrenbach, Jessica Bo Li Lu, Ying-Hua Cheng, Ricardo Melo Ferreira, Evan Rajadhyaksha, Kelsey McClara, Mahla Asghari, Asif A. Sharfuddin, Pierre C. Dagher, Laura M. Snell, Meena S. Madhur, Rafael B. Polidoro, Zeruesenay Desta, Michael T. Eadon
Usage data is cumulative from November 2025 through January 2026.
| Usage | JCI | PMC |
|---|---|---|
| Text version | 843 | 0 |
| 359 | 0 | |
| Figure | 179 | 0 |
| Table | 10 | 0 |
| Supplemental data | 183 | 0 |
| Citation downloads | 88 | 0 |
| Totals | 1,662 | 0 |
| Total Views | 1,662 | |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.