Marijuana Alone Reduced Inflammation in HIV-Positive Youth, But Adding Tobacco Reversed the Effect | Research

The takeaway

Among virally suppressed youth with HIV, marijuana use alone was linked to elevated anti-inflammatory IL-10 and normalization of inflammatory gene pathways, while tobacco use (alone or with marijuana) drove pro-inflammatory responses.

HIV clinicians, immunology researchers, youth health providers

Marijuana alone normalized pro-inflammatory genes in HIV-positive youth, but adding tobacco reversed the effect

What the researchers found

Marijuana use alone was associated with elevated IL-10 levels and normalization of pro-inflammatory genes, suggesting an immunomodulatory effect. Tobacco use alone or combined with marijuana was linked to increased IL-1-beta and upregulated inflammasome activation genes. The study also identified GPR15 upregulation and potential epigenetic changes associated with marijuana use.

Why it matters

Youth with HIV face lifelong antiretroviral therapy and elevated comorbidity risk. Understanding how common substances like marijuana and tobacco affect their immune system is critical for managing long-term health, especially given marijuana's increasing popularity in this population.

The numbers in context

Marijuana alone: elevated IL-10, normalized pro-inflammatory gene pathways; tobacco alone or with marijuana: increased IL-1-beta, upregulated inflammasome genes; first study to demonstrate GPR15 upregulation with marijuana in HIV-suppressed youth; virally suppressed (50 or fewer RNA copies/mL)

How the study worked

Multi-modal profiling of virally suppressed youth with HIV on ART, including plasma biomarker analysis, peripheral blood cell phenotyping, and transcriptome profiling. Groups compared: marijuana only, tobacco only, marijuana plus tobacco, and no substance use.

What this study cannot tell us

Cross-sectional design cannot prove causation, relatively small sample, self-reported substance use, virally suppressed participants may not represent all youth with HIV, cannot determine dose-response relationships

How to read the evidence

Novel multi-modal profiling study but cross-sectional design with a small sample; first to examine these interactions in virally suppressed youth

When this study was published

Published 2025

The bigger picture

The finding that marijuana alone may have anti-inflammatory effects while tobacco reverses them has practical implications: youth with HIV who use both substances may not get the immune benefits some attribute to marijuana, while those using marijuana alone may see a different immune profile.

Questions still open

Does marijuana's apparent anti-inflammatory effect in HIV-positive youth translate to better long-term health outcomes? Could marijuana use reduce the chronic inflammation associated with HIV, even with viral suppression? Should cessation counseling prioritize tobacco over marijuana in this population?

Common questions

Does marijuana reduce inflammation in people with HIV?

In this study of virally suppressed youth with HIV, marijuana use alone was associated with anti-inflammatory changes including elevated IL-10 and normalized pro-inflammatory gene expression. However, this was a cross-sectional observation, not proof of a treatment effect.

Does using tobacco with marijuana change its immune effects?

Yes. Tobacco use, whether alone or combined with marijuana, was linked to increased pro-inflammatory markers and inflammasome activation, effectively overriding the anti-inflammatory pattern seen with marijuana alone.

Read the original research

Multi-Modal Profiling Reveals Contrasting Immunomodulatory Effects of Recreational Marijuana Used Alone or with Tobacco in Youth with HIV.

Cells, 14(16)

View on PubMed ↗Publisher’s paper ↗

Citation

Borkar, Samiksha A; Venturi, Guglielmo M; Chang, Kai-Fen; Gu, Jingwen; Yin, Li; Shen, Jerry; Fischer, Bernard M; Nepal, Upasana; Raplee, Isaac D; Kim-Chang, Julie J; Murdoch, David M; Nichols, Sharon L; Hightow-Weidman, Lisa B; Somboonwit, Charurut; Sleasman, John W; Goodenow, Maureen M. (2025). Multi-Modal Profiling Reveals Contrasting Immunomodulatory Effects of Recreational Marijuana Used Alone or with Tobacco in Youth with HIV.. Cells, 14(16). https://doi.org/10.3390/cells14161267