How Cannabinoids Control the Immune System: Opportunities and Challenges | Research

The takeaway

The endocannabinoid system is widely expressed in immune cells and deeply influences inflammation, autoimmunity, anti-tumor responses, and pathogen defense, creating both therapeutic opportunities and safety concerns.

Read this if you want to understand how cannabis affects the immune system and what that means for conditions involving inflammation or immune dysfunction.

Cannabinoids affect nearly every type of immune cell with generally immunosuppressive effects

What the researchers found

This review summarized how the endocannabinoid system influences the immune system at multiple levels.

Cannabinoids affect nearly every type of immune cell: T-cells, B-cells, macrophages, dendritic cells, mast cells, and others. The general tendency is immunosuppressive, reducing inflammation and modulating immune responses. This makes cannabinoids potentially useful for inflammatory and autoimmune conditions like multiple sclerosis.

However, the immunosuppressive effects also raise concerns. Dampened anti-pathogen immunity could increase infection susceptibility, and altered anti-tumor immunity could theoretically affect cancer surveillance.

The review examined both in vitro and in vivo evidence, noting that the effects are complex and context-dependent. Cannabinoid signaling can both promote and suppress different immune responses depending on the cell type, receptor, and physiological context.

The therapeutic potential extends to organ transplantation (preventing rejection) and inflammation-related diseases, but the dual nature of immunomodulation means careful targeting is needed.

Why it matters

Understanding how cannabinoids interact with the immune system is essential for both medical cannabis patients (who need to know the implications) and drug developers (who need to harness the beneficial effects while minimizing immune compromise).

The numbers in context

The review covers both CB1 and CB2 receptors, endocannabinoids (AEA, 2-AG), and multiple phytocannabinoids across T-cells, B-cells, macrophages, dendritic cells, and other immune cell types.

How the study worked

Review of recent findings on cannabinoid signaling in innate and adaptive immunity, covering in vitro experiments, animal models, and clinical observations. Summarized therapeutic potential and identified open questions and challenges.

What this study cannot tell us

Comprehensive review but much evidence is from in vitro and animal studies. The complexity of the endocannabinoid-immune interaction makes simple predictions about clinical outcomes difficult. The review does not provide meta-analytic quantification of effects.

How to read the evidence

Comprehensive review integrating in vitro, animal, and clinical evidence. Moderate because the evidence base is substantial but complex and not always consistent.

When this study was published

Published in 2017.

The bigger picture

The widespread expression of the endocannabinoid system in immune cells suggests it evolved as a fundamental immune regulatory mechanism. Harnessing this system therapeutically requires understanding both its immunosuppressive benefits (for autoimmune diseases) and its potential costs (for infection defense and cancer surveillance).

Questions still open

Could immune-targeted cannabinoid compounds be developed that do not enter the brain? Would long-term cannabis use measurably increase infection or cancer risk through immunosuppression? Can the endocannabinoid system be targeted to improve organ transplant outcomes?

Common questions

Does cannabis affect the immune system?

Yes. The endocannabinoid system is expressed in nearly all immune cell types. Cannabinoids generally suppress immune responses, which could be beneficial for autoimmune conditions but potentially harmful for fighting infections.

Could cannabis help autoimmune diseases?

The immunosuppressive properties of cannabinoids make them candidates for autoimmune conditions. MS is the most studied example, but the same immune suppression raises concerns about reduced ability to fight infections and potentially altered cancer surveillance.

Read the original research

Targeting Cannabinoid Signaling in the Immune System: "High"-ly Exciting Questions, Possibilities, and Challenges.

Frontiers in immunology, 8, 1487

View on PubMed ↗Publisher’s paper ↗

Citation

Oláh, Attila; Szekanecz, Zoltán; Bíró, Tamás. (2017). Targeting Cannabinoid Signaling in the Immune System: "High"-ly Exciting Questions, Possibilities, and Challenges.. Frontiers in immunology, 8, 1487. https://doi.org/10.3389/fimmu.2017.01487