HIV, human immunodeficiency virus, destroys CD4 cells, also known as helper T cells, in the immune system. Without these cells, bodies have a hard time fighting off various diseases. While there is currently no cure for HIV, people now live long and fulfilling lives with it when treated medically.

Long-term medical treatment isn’t ideal, however, making the fight far from over. Researchers are constantly looking for ways to develop new treatments. One reason HIV is hard to eliminate is its ability to escape drug treatment by hiding in the body, including in the lymph nodes and spleen.

Infected cells hole up in an area of the lymph tissue called the B cell follicles. Immune cells, including T cells and natural killer (NK) cells, whose job is to kill virally infected cells, are generally unable to reach the B cell follicles, making them a safe space for the virus.

Using findings from a previous study published in the Proceedings of the National Academy of Sciences in 2017 focused on B cells, a research team at Emory National Primate Research Center (EPC) studied rhesus macaques with chronic SIV infection.  

“Infiltration of these highly cytotoxic NK cells in the B cell follicles has never been shown before during chronic HIV/SIV,” says senior author Vijayakumar Velu, Ph.D., an assistant professor in the Division of Microbiology and Immunology at the EPC. “This study has implications for developing new cure strategies for HIV, as these cells traffic to B cell follicles during controlled infection,” says co-author Rama Amara, Ph.D.

While more research is needed before introducing new treatments to humans, it’s a huge step in ultimately finding a cure for those living with HIV.

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. 

The immune system has long been touted as the body’s primary defense against invading viruses, with the understanding that a strong immune response swiftly knocks out an infection while a weak one allows it to linger, leading to prolonged disease or even death.

Now, researchers at Tulane University are looking at an entirely different system—the body’s ability to use nutrients at a cellular level — to predict disease response and severity.

Tulane immunologist Clovis Palmer, PhD, studies metabolic changes resulting from viral infections. In a literature review published in Nature Metabolism, Palmer analyzed a body of evidence that looked at the metabolic changes that occur in cells when viral invaders, such as HIV, hepatitis B, or SARS-CoV-2, pose a threat.

Palmer concluded that the way in which cells, even non-immune cells, use nutrients in the presence of a viral pathogen can determine disease outcome and severity in the earliest stages of infection, or even long after the pathogen leaves the body.

Certain molecules on the surface of a cell determine how nutrients are used. These allow nutrients like glucose and fat to facilitate energy production or, if necessary, mount an offense against invading pathogens. Under these conditions, nutrients strengthen and bolster the cell. But viral pathogens can also hijack these surface molecules to gain entry into the cell and then use the nutrients to replicate.

“Whether nutrients are used to strengthen and defend the cell or are hijacked by the virus depends on conditions in the host like older age, nutritional status and obesity,” Palmer said. “We saw that these were all significant risk factors for the worst outcomes of COVID but didn’t really know what was driving it.”

Understanding how cells use nutrients in the presence of viral pathogens at the earliest states of infection is key to the development of treatments that can strengthen the cell, not the virus. While most antiviral medications take aim at the virus, Palmer seeks to prevent or lessen disease by keeping the nutrients on the cell’s side.

Palmer is working with Jay Rappaport, PhD, director of the Tulane National Primate Research Center and professor of microbiology and immunology at the Tulane University School of Medicine, on rewiring metabolic response in nonhuman primate models of COVID and HIV to prevent and treat long-term symptoms.

“We know that when metabolism is impaired, there is increased susceptibility to infection,” said Rappaport. “Modulating the metabolic response has vast implications for all infectious diseases, from optimizing immunity to mitigating the effects of aging, autoimmunity, and other drivers of disease.”

Coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus. While the disease is relatively new, researchers are now studying its long-term effects. Some people with COVID-19 experience little to no symptoms, while others continue to experience fatigue, respiratory and neurological symptoms.

According to a recent report, eighty percent of individuals hospitalized for COVID-19 reported neurological symptoms. Because of this, researchers from the California National Primate Research Center at the University of California, Davis, decided to explore this complex issue further. The findings reveal significant neuron damage and inflammation in rhesus macaque monkeys within a week of infection.

In addition, the study unveiled an exacerbated effect in older rhesus macaques and those with Type 2 diabetes. The virus spread further in the brain, by traveling through the nose along the olfactory nerve, in aged animals and affected their memory and cognition causing particular concerns about potential spikes in neurodegenerative diseases in humans.

John Morrison, professor of neurology at UC Davis and director of the CNPRC, states, “In the aged monkeys, in particular, the virus is infecting neurons in regions known to be highly vulnerable to Alzheimer’s disease.” 

The researchers plan to continue to study the brain post-infection to examine the extent and nature of brain damage underlying the long-term neurological complications of COVID-19 to help doctors better understand how to help humans affected by the disease.

Giving birth is one of the most exciting times in parents’ lives. And doctors do everything in their power to help deliver healthy babies. This often includes providing antibiotics to protect infants from contracting an infection during vaginal or cesarean deliveries.

Currently, antibiotics directed at a wide range of bacteria are prescribed to 4-10% of all newborns.* However, new research conducted by the Cincinnati Children’s Hospital Medical Center (CCHMC) and the California National Primate Research Center (CNPRC) reveals that antibiotic treatments in newborns can change the immune system’s response to lung infections like pneumonia. 

 Researchers studied a group of rhesus macaque infants and their reactions to antibiotics vs. a group that did not receive the medication. The result? The animals that received antibiotics showed a more severe reaction to pneumonia than the control group. 

 “Early life antibiotic use has been linked to chronic health conditions in children but we don’t understand the underlying biology of these effects. This important study is the first to provide experimental evidence of a potential negative effect of antibiotic treatment in infancy in a relevant animal model of childhood development,” said Dr. Lisa Miller, co-author on the study.

The researchers will continue their studies in other animals, including mice, to eventually test and screen human babies as part of preparing to help those more at risk of contracting pneumonia after receiving antibiotics during birth.

Researchers also have a clear message for parents: infants who need antibiotics should still get them. Antibiotics transform lethal infections into minor diseases and have saved countless lives. 

“The next step is to learn how to balance the benefits of antibiotic treatment with the impact on the immune system to avoid potential health risks in susceptible infants,” says Miller.

Approximately 30,000 cases of Lyme disease are reported to CDC every year. Lyme disease transmits the Lyme disease-causing bacteria to humans through the bite of infected ticks with symptoms including fever, headaches, tiredness, and a skin rash. If Lyme is left undetected, the infection can infect the body’s joints, heart, and even nervous system. These patients can suffer from severe neurological issues, significantly diminishing their quality of life.

While antibiotics can effectively treat most cases that are detected early,, undetected infections become harder to eradicate and can cause more prolonged-term effects on people. Research about these neuroinflammation symptoms associated with Lyme disease is limited and evolving. 

 Recently, researchers at the Tulane National Primate Research Center discovered remnants of B. burgdorferi, the bacteria causing Lyme disease, may contribute to inflammation in the nervous system. In fact, these remnants can be more inflammatory (and can also cause cell death) than live bacteria, according to the trials using nonhuman primates. 

While antibiotics kill most intact bacteria in organs, some individuals cannot completely rid themselves of the remnants. Geetha Parthasarathy, Ph.D., assistant professor of microbiology and immunology at the Tulane National Primate Research Center, explains, “As neuroinflammation is the basis of many neurological disorders, lingering inflammation in the brain due to these unresolved fragments could cause long-term health consequences.”

According to the CDC, there are currently 83,949,036 cases of Covid-19 reported in the United States. We all know someone who has been through Covid-19. Headaches, runny nose, congestion, and losing the ability to taste food are common symptoms. But, until now, there have remained many questions surrounding how COVID-19 affects the central nervous system—especially in patients who haven’t experienced a lot of respiratory symptoms. 

While damage to the central nervous system is increasingly evident, the origin remains unclear. Understanding the effects will ultimately help discover and implement future treatments.

Recently, researchers at Tulane University evaluated the neuropathology damage associated with SARS-CoV-2 infection in a nonhuman primate. As it turns out, severe brain inflammation and injury consistent with reduced blood flow or oxygen to the brain, including neuron damage, death, and more, are consistent markers, especially with primates who had little to no respiratory issues. These findings are also compatible with ones reported on autopsied human brains who died from a SARS-CoV-2 infection.

Dr. Tracy Fischer, lead investigator and associate professor of microbiology and immunology at the Tulane National Primate Research Center, states, “Because the subjects didn’t experience significant respiratory symptoms, no one expected them to have the severity of disease that we found in the brain. But the findings were distinct and profound, and undeniably a result of the infection.”

HIV (human immunodeficiency virus) attacks the body’s immune system and, if not treated, can lead to AIDS (acquired immunodeficiency syndrome).

Because of medical advancements, including antiretroviral therapy (ART), many people now live long lives with HIV, but researchers believe long-term viral control in the absence of ART (i.e. remission) might be possible. 

In pursuit of an HIV remission, researchers at the Emory National Primate Research Center (EPC) are working to lower HIV persistence. They recently discovered the anti-inflammatory protein, interleukin-10, may be responsible for helping sustain cellular reservoirs, which enable the virus to hide. This breakthrough may lead to treatments that can block the effects of interleukin-10 and, therefore, reduce viral persistence, which is critical to finding alternative therapies to control HIV. 

The team worked with rhesus macaques infected with simian immunodeficiency virus (SIV), the animal form of HIV, to determine how interleukin-10 regulates the survival of cells known to harbor HIV. The team also studied the effects of blocking this protein to determine if doing so would reduce the persistence of the virus when used in combination with ART.

Mirko Paiardini, PhD, senior author of the study, said when his research team looked at lymph node tissues, they found the vast majority of cells infected with SIV were within close proximity to cells expressing interleukin-10. This was the case in both chronically infected animals and in those treated with ART.

The team found in the monkeys treated with ART and an antibody against interleukin-10 a significant reduction in the frequency of immune cells harboring SIV in the macaques’ lymph nodes. The discovery confirms Interleukin-10 signaling is critically involved in promoting the survival of the cells harboring the virus and warrants further research in nonhuman primates.

Many previous studies explain how exposure to certain environmental substances during pregnancy may affect your baby’s health. Toxic substances increase the risk for congenital disabilities, low birth weight, prematurity, and miscarriage.

Studying the long-term effects of various environmental changes during pregnancy has occurred for decades¾from exposure to metals, cigarette smoke, stress, radiation, and more. But, recently, a new study at the California National Primate Research Center at the University of California, Davis, was published exploring the effects of wildfire smoke exposure during early pregnancy on a group of infant monkeys.

It’s typically challenging to study exposure to environmental variations during early pregnancy in women because they often aren’t aware of their pregnancies until weeks after conception. But a fire beginning on November 8, 2018, in Davis, California, provided a natural experiment in wildfire smoke exposure for a group of rhesus macaques housed close by in outdoor corrals at the California National Primate Research Center during mating season. Just under 90 monkeys were born six months later.

After months, studies proved the baby monkeys exposed to smoke had increased inflammation, reduced cortisol response to stress, memory deficits, and a more passive temperament than other animals.

Because of this study’s findings, Bill Lasley, professor emeritus of population health and reproduction at the UC Davis School of Veterinary Medicine and Center for Health and Environment, plans to study women who became pregnant through IVF. This allows him and his team to look at more prolonged-term effects of wildfire exposure with the added benefit of knowing the exact time of conception.

Human immunodeficiency virus (HIV) attacks the body’s immune system, resulting in rashes, fevers, fatigue, swollen lymph nodes, and other symptoms. It affects over 37 million people globally. When left untreated, HIV infections can progress to acquired immunodeficiency syndrome (AIDS), leading to a damaged immune system, severe opportunistic infections, and death.

Most replicating HIV – and its monkey version, simian immunodeficiency virus (SIV) – is found in follicles of the lymphoid tissues. However, most cytotoxic T-lymphocytes, the cells clearing HIV from the body, cannot reach the follicles. This explains the need for lifelong use of antiretroviral therapy’s current standard treatment. However, only 57% of those living with HIV are undergoing antiretroviral therapy, which leaves the rest able to infect others with the virus. Therefore, there is an urgent need for new treatment options, especially for those who do not have lifelong access to healthcare.

A group of AIDS researchers working with immunology and animal care experts on rhesus monkeys at the Wisconsin National Primate Center investigated the possibility of a new therapy targeting virus-specific T-cells to the follicles. They did so by engineering therapeutic T-cells to enter and concentrate in the lymphoid follicles to reduce viral replication. Led by Pamela Skinner, professor of veterinary and biomedical sciences at the University of Minnesota, the team used T-cells to express a chimeric antigen receptor (CAR) targeting the SIV virus. They added a follicular homing receptor called CXCR5 so the CAR/CXCR5 T-lymphocytes could kill the infected cells in the lymphoid follicles. The homing receptor allowed the T-cells to migrate into the follicles, which previously limited the effectiveness of the body’s response to infection.

In six SIV-infected rhesus monkeys, the CAR/CXCR5 T-cells were able to migrate to the follicles within two days and directly interact with the virally infected cells. Fluorescent imaging allowed the researchers to discover these T-cells could replicate and increase within the follicles. Even though levels of the specialized T-cells declined within four weeks after administration, the treated primates were able to maintain lower concentrations of SIV in their blood and follicles than those not given the CAR/CXCR5 T-cell immunotherapy. The researchers and veterinarians also looked at possible side effects of this treatment and found none of the primates had a poor reaction to T-cell administration.

The study, published in Public Library of Science Pathogens, provided preliminary evidence for effective and safe treatment of engineered T-cells for HIV infection. Data from these researchers set the stage for future preclinical studies involving larger populations of non-human primates to confirm the effectiveness of this treatment, along with studies looking at combining this treatment with other therapies.