Asthma, a prevalent chronic lung condition affecting millions worldwide, remains a significant health concern. However, recent breakthroughs in research conducted at the California National Primate Research Center (CNPRC) offer hope for a deeper understanding of the disease and potential avenues for treatment. 

Insights from CNPRC’s Inhalation Exposure Core 

The CNPRC’s Inhalation Exposure Core provides a unique platform for investigating the environmental influences on asthma development. Due to its location in Northern California, where wildfire smoke and air pollution can occur, this facility is instrumental in studying mechanistic and therapeutic aspects of lung diseases. Collaborating with experts from the CNPRC Cardiorespiratory Diseases Unit, researchers explore asthma’s origins in both children and adults, crucial for developing effective treatment strategies. 

As of now, there isn’t a cure for asthma, but progress continues to be made through research and there are treatments available to help manage and control its symptoms. Lisa Miller, head of CNPRC’s Inhalation Exposure Core, emphasizes the importance of nonhuman primate models in asthma research, offering insights into the disease across different stages of life. 

Understanding Asthma Variability 

Asthma is characterized by airway sensitivity to environmental triggers, which can lead to restricted breathing and potentially fatal consequences if untreated. The disease varies among patients, with some, particularly adult females, experiencing non-allergen induced asthma resistant to standard treatments.  

A recently developed nonhuman primate model of non-atopic asthma mirrors human conditions and could offer significant benefits to approximately 7.5 million Americans. Rhesus macaques can naturally exhibit airway hyperreactivity akin to non-allergen induced asthma, making this model remarkably reproducible and valuable for research purposes. 

Early Behavior, Later Breathing 

A unique longitudinal study conducted at CNPRC, known as the biobehavioral assessment program (BBA), revealed intriguing connections between infant behavior and later asthma development. Behavioral inhibition, a temperament defined by fearful responses to novelty, in infancy correlated with airway hyperreactivity in juveniles and adults, highlighting the interplay between behavior and health outcomes.  

CNPRC researchers discovered a link between behavioral inhibition in infancy and the development of asthma phenotypes. They conducted a study involving 49 rhesus macaque monkeys, tracking their development from infancy to yearling status. Of these monkeys, 24 exhibited behavioral inhibition during infancy and later showed airway hyperresponsivity as juveniles. 

The Right Resources for Research 

CNPRC’s Inhalation Exposure Core, comprising expert scientists and advanced facilities, is pivotal in testing potential asthma treatments and airway hyperreactivity, either naturally in non-atopic asthma or in response to toxic inhalants such as the pollutant ozone (O3).  

Recent studies, including one involving a novel drug derived from flaxseed, showcased promising results in preventing immune changes related to asthma symptoms and help assess whether the non-atopic asthma monkey model would be sensitive to novel antioxidant compounds. 

Results revealed specific immune changes caused by O3 exposure, and the treatment successfully prevented immune changes associated with asthma symptoms. Consequently, the drug tested in the rhesus macaque model of non-atopic asthma is now slated for clinical trials in human asthmatics. 

Further Exploration 

As asthma manifests in various forms and developmental stages, the rhesus monkey model remains crucial for developing and testing new therapies. The CNPRC’s Inhalation Exposure Core stands as a beacon of hope in translational cardiorespiratory disease research, offering invaluable insights with global implications. 

In conclusion, the ongoing research at CNPRC not only unveils a reproducible animal model of human asthma but also underscores the intricate relationship between behavior, personality, and health. These findings pave the way for further exploration into asthma’s complexities and the development of targeted interventions, offering hope for asthma patients worldwide. 

Recent research conducted at the California National Primate Research Center (CNPRC) has uncovered fascinating insights into the perception of touch in nonhuman primates, shedding light on how our brains process pleasurable sensations. Led by Ph.D. Candidate Joey Charbonneau and CNPRC core scientist Eliza Bliss-Moreau, the study investigates the neural responses to gentle, pleasurable touch. Given that the animals were anesthetized, researchers were surprised to find that the brain activity in monkeys mirrored that of humans experiencing pleasant touch. 

Published in the Proceedings of the National Academy of Sciences, the study unveils age-related differences in touch perception, sparking intriguing questions about consciousness and the brain’s processing of tactile stimuli. Understanding these mechanisms not only illuminates fundamental aspects of neuroscience but also has implications for various human conditions, from autism spectrum disorder to neurodegenerative diseases like Alzheimer’s. 

Using functional magnetic resonance imaging (fMRI), researchers examined the brain activity of monkeys who were anesthetized in response to slow, pleasurable touch (also known as affective touch) and faster, discriminative touch (referred to as discriminative touch). Remarkably, they found that the same brain regions activated from pleasurable touch in awake humans and monkeys who were not awake. This suggests that the rewarding aspects of affective suggests that touch transcend species boundaries and do not necessarily require consciousness. 

Moreover, the study identified age-related changes in how touch is represented in the brain, particularly in regions associated with affective processing. Older monkeys exhibited alterations in brain activity patterns to discriminative but not affective touch, highlighting the importance of considering age-related factors in understanding touch perception. 

Nonhuman primates serve as invaluable models for studying touch perception, offering insights that could inform additional research. By leveraging this model, researchers aim to understand the mechanisms underlying touch perception across the lifespan and develop interventions for age-related diseases impacting affective processing. 

This pioneering work, supported by the National Institute of Health and other funding sources, represents a crucial step toward unraveling the mysteries of touch perception and its implications for human health and well-being. 

The human immunodeficiency virus (HIV) remains a formidable challenge for medical researchers worldwide. While antiretroviral therapy (ART) has allowed individuals to manage HIV as a chronic condition and significantly improve their quality of life, certain aspects of the virus’s behavior still elude full comprehension. Among these mysteries lies the infiltration of HIV into the brain, a phenomenon with profound implications for individuals living with the virus. 

A groundbreaking study conducted at the California National Primate Research Center (CNPRC) is shedding new light on this intricate process. Led by Smita Iyer, an Associate Professor in the Division of Experimental and Translational Pathology at the University of Pittsburgh School of Medicine, led the study during her tenure as a CNPRC core scientist. The research offers insights into how HIV spreads within neural tissue and its implications for HIV-associated neurodegenerative disorders (HAND). 

Published in December 2023 in PLoS Pathogens, the study utilized nonhuman primate models to map the immune response to HIV in the brain. By focusing on immune cells known as CD4 T cells, the researchers uncovered the virus’s ability to penetrate neural tissue, thus highlighting its role in HAND. 

The significance of this research extends beyond HIV alone. As many individuals experienced with the cognitive impairments associated with COVID-19 can attest, viral invasion of the brain can have profound and enduring consequences. Nonhuman primate models, like those utilized at CNPRC, are instrumental in unraveling the mechanisms by which viruses breach the blood-brain barrier and persist within the central nervous system. 

Despite the success of ART in suppressing HIV replication in the bloodstream, some patients continue to experience chronic inflammation in the central nervous system. Known as Neuro-HIV, this condition underscores the virus’s unique ability to infiltrate the brain, disrupting neural function and potentially leading to cognitive decline. 

The CNPRC’s pioneering work in HIV and ART research has paved the way for advancements in understanding and combating the virus. From developing the simian immunodeficiency virus (SIV) model to conducting safety testing for crucial antiretroviral drugs, CNPRC’s contributions have been instrumental in the fight against HIV. 

Iyer’s study represents a continuation of CNPRC’s legacy, leveraging state-of-the-art technologies to track the progression of HIV within brain tissue. By elucidating the role of CD4 T cells in facilitating viral entry into the brain, the research provides valuable insights into the pathogenesis of Neuro-HIV. 

The findings of the study challenge conventional wisdom regarding the role of CD4 T cells in the body’s immune response to HIV. Rather than acting as guardians against viral invasion, these cells appear to serve as unwitting accomplices, aiding the virus in spreading throughout the body, including the brain. 

Looking ahead, Iyer and her team are focused on unraveling the complex interplay between different subsets of CD4 T cells during long-term HIV infection.  

By deciphering these intricate mechanisms, researchers aim to gain a deeper understanding of HIV’s impact on the central nervous system and develop targeted interventions to mitigate its effects. As they piece together the puzzle of Neuro-HIV, the quest for effective treatments and ultimately a cure continues unabated. 

Research in nonhuman primates is opening new possibilities for testing treatments for early-stage Alzheimer’s disease and similar conditions before extensive brain cell death and dementia set in. A recent study published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association reveals a six-month window during which disease progression can be tracked and treatments tested in rhesus macaques. 

“This is a very powerful translational model to test interventions that target the tau protein,” said John H. Morrison, professor of neurology at the University of California, Davis, and California National Primate Research Center, and corresponding author on the paper. 

 The Role of Tau Protein in Alzheimer’s Disease 

The tau protein, found in neurons, is implicated in Alzheimer’s disease, frontotemporal dementia, and other dementias. Misfolded tau disrupts essential brain cell functions, spreading through connected regions of the cortex that are crucial for memory and cognition. This leads to an inflammatory response and eventually neuron death. 

Advances in brain imaging, biomarkers in human serum and cerebrospinal fluid, and rodent models have improved our understanding of early-stage Alzheimer’s. However, the relationship between tau, inflammation, and disease progression remains complex. The macaque model bridges the gap between mouse models and human patients, better representing the disease’s progression. 

The Six-Month Window for Disease Progression 

In the study, researchers injected a vector carrying DNA for two mutated tau proteins into the entorhinal cortex of 12 monkeys. This brain region, involved with memory, is where Alzheimer’s typically originates in humans. Over six months, they tracked the spread of tau protein, affected cells, and inflammation using PET and MRI imaging, biomarkers, and microscopy. 

The results indicate a window of at least two to six months where disease progress can be measured, allowing for preclinical testing of interventions targeting the tau protein. “We can look at drugs targeting early-stage Alzheimer’s before dementia develops,” Morrison said. “It’s all about early intervention to arrest progression.” 

This study builds on earlier work at the CNPRC establishing the nonhuman primate model. Future research will combine the tau model with existing systems based on amyloid, further enhancing our understanding and treatment of Alzheimer’s disease. 

In the battle against opioid addiction, a groundbreaking development has emerged: a novel vaccine designed to combat oxycodone addiction. This innovative vaccine has shown promise by generating antibodies in the bloodstream, effectively preventing the drug from reaching the brain and exerting its addictive effects. 

Funded by the California National Primate Research Center’s Pilot Research Program at the University of California, Davis, the study behind this vaccine sheds light on a potential therapeutic option for the millions affected by opioid use disorder (OUD) in the United States. 

Led by Kathryn Frietze, an assistant professor at the University of New Mexico School of Medicine, along with graduate student Isabella Romano, the research evaluated the vaccine’s protective abilities in animal models. Notably, the study also explored the vaccine’s interactions with other OUD treatments, such as Methadone and Buprenorphine. 

The mechanism of action behind this vaccine is intriguing. By stimulating the production of antibodies that recognize and bind to oxycodone, the vaccine hinders the drug’s ability to cross the blood-brain barrier and bind to specific receptors in the brain. This impediment prevents the drug from exerting its addictive effects, offering a novel approach to addiction treatment. 

Results from the study demonstrated the vaccine’s efficacy in elevating antibody levels in both mice and nonhuman primates. Importantly, the vaccine showed no adverse health effects and effectively prevented oxycodone from reaching the brain when challenged with the drug. 

Beyond its efficacy, the vaccine also offers practical advantages for clinical use. It remains effective following temperature fluctuations, making it suitable for real-world clinic settings. Moreover, it exhibits minimal cross-reactivity with other OUD treatments, ensuring compatibility with existing treatment plans. 

Looking ahead, Frietze and her team will continue to investigate the vaccine’s protective capacity, focusing on its effects on respiratory depression and pain perception. They will also explore whether vaccinated animals remain responsive to other OUD treatments. 

As Romano emphasizes, addressing concerns and acceptability issues from both patients and providers is crucial in the development of opioid vaccines. By addressing these obstacles, researchers aim to position vaccines as a viable and accessible treatment option for opioid addiction, offering hope for a brighter future in the fight against this devastating epidemic.

A team of researchers recently delved into lower urinary tract (LUT) dysfunction, a common issue among older adults that brings challenges like incontinence, urinary infections, and reliance on catheters. These struggles often lead to a loss of independence and a need for extended care. But what causes this problem?

Researchers at the California and Wisconsin National Primate Research Centers alongside researchers from the Icahn School of Medicine at Mount Sinai set out to uncover the secrets behind LUT dysfunction, focusing on adult and aged female rhesus monkeys, giving them insights into how the issue develops in humans.

They discovered a connection between detrusor underactivity (DU), which affects bladder muscle tone, and specific metabolic markers. These markers act like clues that help researchers understand the bigger picture.

The bladder’s functioning relies on smooth muscle fibers arranged in a pattern known as the detrusor muscle. This unique structure allows the bladder to stretch and contract effectively.

Researchers also noticed patterns among the aged subjects. These subjects exhibited markers commonly associated with metabolic syndrome, such as changes in weight, triglyceride levels, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), and high-sensitivity C-reactive protein (hsCRP). Interestingly, some markers, like Aspartate aminotransferase (AST), remained unchanged, while the AST/ALT ratio took an unexpected turn.

This means there is a link between detrusor underactivity and metabolic syndrome in older female primates. Factors like prior pregnancies and menopause didn’t sway the results, making this connection even more intriguing.

Dr. Ricki Colman, an associate professor of cell and regenerative biology at the University of Wisconsin–Madison and one of the study’s authors, emphasized the practical significance of their findings: “Our findings provide insights into possible mechanisms for age-associated detrusor underactivity and may guide new strategies to prevent and treat LUT dysfunction in older adults.”

As this chapter in the research unfolds, it’s clear that the relationship between LUT dysfunction and metabolism holds promise for shedding light on a common issue and uncovering new ways to address it.

National Primate Research Centers Prioritize Openness for Scientific Progress

At the forefront of biomedical and behavioral research are the seven National Primate Research Centers (NPRCs). They form a vital network dedicated to conducting and enabling groundbreaking research to improve human and animal health. Studies at the centers include development & aging, genetics & genomics, infectious disease, neuroscience & brain disorders, and reproduction & endocrinology. The NPRCs have been instrumental in driving discoveries crucial for overcoming health challenges and in helping the public understand the significance of research that involves animals.   

A Comprehensive Approach  

A priority of the NPRCs is to share information via local, regional and national outreach. Through a multifaceted approach, the NPRCs foster education and dialogue, ensuring openness about their research and the expert care of animals involved in NPRC research studies.   

From participating in local events to leveraging digital platforms, the NPRCs employ diverse strategies to make connections. NPRC.org provides the latest information for the public, and NPRCresearch.org, which is undergoing updates, ensures the scientific community has comprehensive information about the resources the NPRCs offer NIH-funded researchers. Through timely and engaging content, the NPRCs strive to explain the highly regulated research process and showcase their contributions to scientific progress.   

A Legacy of Excellence  

With a history spanning more than six decades, the NPRCs stand as pillars of scientific expertise and exemplars of public outreach. The U.S. Animal Research Openness initiative (USARO) recently featured information about the NPRCs’ outreach programs on the USARO website. This article provides encouragement for other research centers to follow the NPRC lead.   

A Future Filled with Accurate Information  

As the NPRCs continue to make scientific discoveries, their dedication to openness will continue to expand. The NPRCs believe openness helps empower individuals to make informed decisions, is critical to instilling confidence in scientific research and care of research animals, inspires future generations of scientists and ensures the public has accurate information about how research with animals is improving lives.  

Every day, the seven National Primate Research Centers (NPRCs) conduct and enable collaborative research studies to improve human and animal health. For more than five years now, we’ve been sharing our latest news and scientific advancements with you via NPRC.org and @NPRCnews (X), and there’s more coming your way. 

To ensure the NPRCs provide the topics of most interest to our readers and followers, we looked back at your favorite stories to help us move forward. Your top interests span behavior and psychology, infectious disease and neuroscience and brain disorders research. We will continue to share news that represents what you have most enjoyed, and we will also bring you information that reflects the breadth and depth of research across the NPRC network.   

We appreciate our readers and followers, and encourage you to take another look at your favorite blogs about NPRC research, to share the information with your family, friends and colleagues, and to continue connecting with us via NPRC.org, @NPRCnews and, now, on the new NPRC LinkedIn account. Via these resources, you’ll always be able to access the latest news on NPRC research that is helping people across generations and around the world live longer, healthier lives.   

Behavior and Psychology 

1. The Effects of Wildfire Smoke Exposure in Early Pregnancy 

A study by California NPRC and UC Davis researchers investigated the effects of wildfire smoke exposure on infant monkeys during early pregnancy. The study found that exposure led to increased inflammation, reduced stress response, memory deficits and a more passive temperament in the monkeys. The findings suggest environmental changes during pregnancy can have lasting effects on offspring.  

Infectious Disease 

2. A Deadly Relationship: Stopping the Progression of Tuberculosis in HIV Patients   

Researchers at the Southwest National Primate Research Center have discovered chronic immune activation in the lungs plays a crucial role in the progression of tuberculosis (TB) and HIV co-infection. This dysfunction hampers the body’s ability to fight off infections. The study suggests the need to develop treatments targeting chronic immune activation alongside antiretroviral therapy (ART). TB and HIV are global pandemics that reinforce each other, affecting a significant portion of the world’s population. The findings offer hope for improved treatment strategies in the next decade. 

3. New Possible Correlation Between Lyme Disease and Lewy Body Dementia  

At Tulane National Primate Research Center, researchers discovered intact spirochetes of Borrelia burgdorferi, the bacterium that causes Lyme disease, in the central nervous system of a 69-year-old woman who received multiple rounds of antibiotic treatment. The presence of this bacterium coupled with her persistent neurological decline raises the possibility of a correlation between Lyme disease and Lewy body dementia. This finding highlights the bacterium’s persistence despite targeted therapy and emphasizes the need for further research to comprehend its role in severe neurological conditions. 

4. Are DNA Vaccinations a Perennial Answer to the Flu?  

Researchers at the Washington National Primate Research Center are developing a universal flu vaccine that could protect against all strains of the influenza virus. Using a DNA vaccine administered through the skin, the team has achieved promising results in macaques, providing 100% protection against a previous flu virus. This approach could eliminate the need for annual flu shots and be quickly deployed during pandemics. The researchers believe this technology could also be effective against other viruses and outbreaks. 

Neuroscience & Brain Disorders 

5. Past Social Experiences May Affect Brain’s Response to Oxytocin

A study at the Emory (formerly Yerkes) National Primate Research Center and Emory University showed the response of neurons to oxytocin, a chemical involved in social bonding, can vary based on an individual’s past experiences. Using female prairie voles, the researchers examined the nucleus accumbens, a brain region related to pair bonding. They found that oxytocin reduced neuron firing before bonding and increased it afterward, when triggered. The study also revealed a connection between oxytocin signals and endocannabinoids, affecting defensive interactions. These findings provide insights into how prior experiences influence oxytocin’s impact on brain circuits. 

6. NPRC Study May Have Found Link That Causes Anxiety and Depression  

Researchers at the Wisconsin National Primate Research Center and the University of Wisconsin-Madison have discovered brain pathways in juvenile monkeys that could contribute to anxiety and depression later in life. By studying the connections between specific brain regions, they found a correlation between synchronization and anxious temperament. These findings may lead to better treatment approaches and help identify gene alterations associated with anxiety. 

7. The Drinking Gene: Could Alcoholism Be Inherited?  

Research conducted at Oregon National Primate Research Center has identified a gene, GPR39, as a potential target for developing medication to prevent and treat alcoholism. By modifying protein levels encoded by this gene in mice, the researchers observed a significant reduction in alcohol consumption. They also found a link between alcohol and the activity of this gene. The study draws attention to the importance of cross-species approaches to identify drugs for treating alcohol use disorder. Further investigations are under way to determine if the same mechanism applies to humans. These findings offer potential insights for developing drugs to address chronic alcoholism and mood disorders. 

Oxytocin is a hormone that plays a critical role in social bonding and attachment. In recent years, researchers have been studying the effects of intranasal oxytocin, a non-invasive treatment that reduces social impairment in several neurological and behavioral disorders, such as autism.  

However, the long-term effects and efficacy of the treatment are currently under examination. Studies conducted by Dr. Karen Bales’ lab at the California National Primate Research Center reveal that chronic intranasal oxytocin produces sex-specific biological and behavioral responses in titi monkeys, a monogamous nonhuman primate.  

The researchers found that all OT-treated monkeys engaged more in social interactions but differed in their social behavior by sex. The males exhibited more social interest in unfamiliar animals, while females directed their interest toward their parents.  

The monkeys were divided into two groups: one received a daily dose of intranasal OT, while the other received saline for six months. The treatment group exhibited more prosocial behavior in their home enclosure immediately following their dose than the control group. 

Researchers also examined neural effects and social behavior during adolescence and into adulthood one-year after treatment ended. As adults, males from the treatment group maintained some prosocial effects. They also scored higher on several measures of affiliative behavior than the control group. Females, however, experienced a slight delay in forming a bond with their new mate. 

The researchers observed that chronic treatments during adolescence altered their behavior long-term, and these behavioral changes were different for males and females. These findings emphasize the complexity of the treatment and lay an essential foundation for more research on its use in humans. 

A collaborator on the project, Dr. Suma Jacob from the University of Minnesota Medical School, explained that “there is more research to be done on oxytocin, how it works, its effects, and feedback systems.”

Covid-19 is a highly contagious and quickly spread disease caused by SARS-CoV-2. Since its discovery in 2019, researchers have remained dedicated to creating a vaccination for people of all ages. While many people with Covid-19 have mild symptoms, others can become highly ill as the disease attacks the lungs and respiratory systems.

In late 2022, the CDC expanded the use of vaccines for children ages six months to 5 years old. The CDC states, “The vast majority of children in this age group have not received any doses of a COVID-19 vaccine. CDC is working to increase parent and provider confidence in COVID-19 vaccines and improve uptake among the 95% of children who are not vaccinated or have not completed the COVID-19 vaccine primary series.”1

A new study from the California National Primate Research Center, UNC-Chapel Hill, and Will Cornell Medicine, determined two-dose vaccines protect against lung disease in rhesus macaques one year after they were vaccinated as infants.

Researchers immunized two groups of eight infant rhesus macaques at the CNPRC at two months of age and again four weeks later.

Each animal received one of two vaccine types: a preclinical version of the Moderna mRNA vaccine or a vaccine combining a protein with a potent adjuvant formulation. One year later, the animals received a high-dose challenge with a SARS-CoV-2 variant to test their immune responses. Both proved successful in protecting against lung disease implying the vaccines are safe and highly effective when given to young infant macaques and may reduce the need for frequent boosters in young children.

Young infants are one of the most vulnerable populations regarding Covid-19. “This study emphasizes the need to get human infants immunized against SARS-CoV-2 as much as possible, as the benefits are clear and long-lasting. It also highlights the value of animal models in infectious disease research,” said Koen Van Rompay, co-author of the study.