New study identifies key mechanism driving HIV-associated immune suppression

The finding offers new insight into why the virus remains difficult to cure even with effective antiretroviral therapy.

2025-11-24

(Press-News.org) Baltimore, MD — Researchers from the Institute of Human Virology (IHV) at the University of Maryland School of Medicine have discovered how a specific type of immune cell may contribute to the persistence of HIV infections. The finding offers new insight into why the virus remains difficult to cure even with effective antiretroviral therapy.

The study was published earlier this month in Science Translational Medicine. It was led by Guangming Li, PhD, and Lishan Su, PhD, Professor of Pharmacology at UMSOM and Director of the Division of Virology, Pathogenesis and Cancer, and Interim Director of the Division of Immunotherapy at IHV.

The researchers focused on plasmacytoid dendritic cells (pDCs)—a rare immune cell type crucial in the body’s early defense against viruses. During chronic HIV infection, these cells become overactivated, driving continuous immune inflammation. This constant activation weakens virus-fighting T cells and allows HIV to persist in hidden reservoirs.

Using humanized mouse models and blood samples from people living with HIV, the team found that reducing overactive pDCs helped restore antiviral T cell function and shrink the viral reservoir. When this approach was combined with an immune checkpoint inhibitor—a therapy that reinvigorates exhausted immune cells—the immune response improved even further.

Why This Research Matters

The findings reveal that while the pDC-interferon pathway is essential for antiviral defense, its overactivation may weaken immune control of HIV. This helps explain why immune inflammation continues in people with HIV despite treatment and why a cure remains elusive.

“This study represents our decade-long effort to understand the complex role of pDCs in HIV-associated diseases,” Dr. Su said. “Our research shows that the immune system’s continued effort to fight infection can sometimes work against itself. By rebalancing this system, we may be able to open new pathways for therapy.”

While most of the study was conducted in laboratory and animal models, key observations were confirmed in blood samples from people living with HIV.

“Future studies will determine whether temporarily adjusting these immune cells can safely improve immune balance and contribute to HIV cure strategies,” said Dr. Li.

This research builds on UMSOM and IHV’s longstanding commitment to advancing HIV biology and developing new therapeutic strategies.

Mr. Yaoxian Lou, PhD candidate of Microbiology & Immunology at UMSOM, Drs. Shyamasundaran Kottilil and Poonam Mathur at IHV/UMSOM are coauthors of the manuscript. Other co-authors on the study include researchers at the University of North Carolina at Chapel Hill and Weill Cornell Medicine. The study was supported by NIH grants (AI136990, CA298839), the National Cancer Institute Cancer Center Support Grant (P30CA134274), and a University of Maryland School of Medicine grant (1UL1TR003098).

END

ELSE PRESS RELEASES FROM THIS DATE:

Connections with nature in protected areas

2025-11-24

Protected areas are often seen as refuges for plants and animals – yet they are also places where people live, work and relax. A new study led by the University of Göttingen in Germany, in collaboration with the Universities of Kassel in Germany, Jyväskylä in Finland, and Stockholm in Sweden, shows how deeply people are connected to these landscapes. The research team analyzed personal stories from residents, land managers, and visitors in protected areas of the district of Göttingen. Their findings reveal that protected areas foster local identity, support learning about nature, and provide spaces for recreation, working ...

Rodriguez and Phadatare selected for SME's 30 Under 30

2025-11-24

Brittany Rodriguez and Akash Phadatare of Oak Ridge National Laboratory’s Manufacturing Science Division (MSD) have been named to SME’s prestigious 30 Under 30 program for 2025. For the past decade, the Society of Manufacturing Engineers has recognized young visionaries in the field — talented individuals with a passion for innovation across manufacturing, research and engineering disciplines. “I am immensely proud of Brittany Rodriguez and Akash Phadatare for their innovative contributions ...

Nontraditional benefits play key role in retaining the under-35 government health worker

2025-11-24

November 20, 2025-- Younger workers in governmental public health place significantly higher value on nontraditional benefits than their older counterparts, according to a new study from Columbia University Mailman School of Public Health. Flexible scheduling and remote-work policies were among the top motivators for younger employees choosing and remaining in public service. The findings are published in the Journal of Public Health Management and Practice. “Public health workers age 35 or younger consistently show lower retention rates ...

UC Irvine-led study finds global embrace of integrative cancer care

2025-11-24

Irvine, Calif., Nov. 24, 2025 — Around the world, doctors, nurses and pharmacists are turning to evidence-based integrative approaches such as acupuncture, yoga, exercise, massage and nutrition counseling to help people with cancer manage the harsh side effects of treatment. New research led by the University of California, Irvine shows just how widespread that shift has become and how much work remains to make these therapies accessible to all. Published this month in BMC Complementary Medicine and Therapies, the study surveyed more than 300 oncology professionals from the Multinational Association of Supportive Care in Cancer and the Society for Integrative ...

From shiloh shepherds to chihuahuas, study finds that the majority of modern dogs have detectable wolf ancestry

2025-11-24

New research led by scientists at the American Museum of Natural History and the Smithsonian’s National Museum of Natural History reveals that the majority of dogs living today have low but detectable levels of post-domestication wolf ancestry that has likely shaped characteristics including body size, sense of smell, and personality traits. The study, published today in Proceedings of the National Academy of Sciences, suggests that this newly uncovered gene flow may help give unique advantages to dogs’ survival in diverse human environments. Among their findings: post-domestication wolf ancestry exists in a wide range of dog breeds, ...

Ancient wolves on remote Baltic Sea island reveal link to prehistoric humans

2025-11-24

Scientists have found wolf remains, thousands of years old, on a small, isolated island in the Baltic Sea – a place where the animals could only have been brought by humans. The study, published in Proceedings of the National Academy of Sciences by researchers at the Francis Crick Institute, Stockholm University, the University of Aberdeen and the University of East Anglia, suggest that grey wolves may have been managed or controlled by prehistoric societies. The discovery of the 3,000–5,000-year-old wolf remains was made in the Stora Förvar cave on the Swedish island of Stora Karlsö, a site known for its intensive use by seal hunters and fishers during the ...

Scientists detect new climate pattern in the tropics

2025-11-24

Tropical cyclones can unleash extensive devastation, as recent storms that swept over Jamaica and the Philippines made unmistakably clear. Accurate weather forecasts that buy more time to prepare are crucial for saving lives and are rooted in a deeper understanding of climate systems. Driving this forward, researchers at the Institute of Science and Technology Austria (ISTA) and others have successfully identified a previously unknown cyclic climate pattern by historical reanalysis of datasets and satellite observations. The findings are published in PNAS. Jiawei Bao still remembers coming home from middle school to ...

‘Mental model’ approach shows promise in reducing susceptibility to misconceptions about mRNA vaccination

2025-11-24

PHILADELPHIA – Correcting misinformation after it has gone viral is a common way of informing the public that what they’ve encountered may be inaccurate, lack context, be unproven, or be demonstrably false. But repeating a misconception when refuting it carries the risk of spreading it to a larger audience, especially because the people who read a fact-checking report may not be the same ones who were originally exposed to the worrisome information. To overcome these challenges, researchers at the Annenberg Public Policy Center (APPC) of the University ...

Want actionable climate knowledge at scale? Consider these three pathways

2025-11-24

There's no one-size-fits-all solution to adapting and building resilience to climate change, but a new study led by the University of Michigan offers three generalized pathways to help climate knowledge achieve its maximum impact. The researchers analyzed available literature and built on their own experiences to distill these separate but complementary pathways for creating new thinking that is not only actionable, but scalable. Published in the journal Proceedings of the National Academy of Sciences, ...

Blood formation: Two systems with different competencies

2025-11-24

It has only recently become known that two parallel systems of blood formation exist in the body, originating from different precursor cells. Researchers at the German Cancer Research Center (DKFZ) have developed a method to examine both systems separately in mice for the first time. Their surprising finding: the majority of immune cells do not originate from classic blood stem cells in the bone marrow, but from precursor cells that are independent of blood stem cells and are already present in the ...