Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia. Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw Read more

Reddit as window into opioid withdrawal strategies

Drug abuse researchers are using the social media site Reddit as a window into the experiences of people living with opioid addiction. Abeed Sarker in Emory's Department of Biomedical Informatics has a paper in Clinical Toxicology focusing on the phenomenon of “precipitated withdrawal,” in collaboration with emergency medicine specialists from Penn, Rutgers and Mt Sinai. Precipitated withdrawal is a more intense form of withdrawal that can occur when someone who was using opioids starts medication-assisted treatment Read more

CROI: HIV cure report and ongoing research

The big news out of CROI (Conference on Retroviruses and Opportunistic Infections) was a report of a third person being cured of HIV infection, this time using umbilical cord blood for a hematopoetic stem cell transplant. Emory’s Carlos del Rio gave a nice overview of the achievement for NPR this morning. As del Rio explains, the field of HIV cure research took off over the last decade after Timothy Brown, known as “the Berlin patient,” Read more

natural killer cells

Natural killer cells can help control virus in primate model of HIV/AIDS

A combination immunotherapy of IL-21 and IFN-alpha, when added to antiviral therapy, is effective in generating highly functional natural killer cells that can help control and reduce SIV (simian immunodeficiency virus) in animal models. This finding, from Yerkes National Primate Research Center scientists in collaboration with Institut Pasteur, could be key for developing additional treatment options to control HIV/AIDS.

The results were published in Nature Communications.

Antiviral therapy (ART) is the current leading treatment for HIV/AIDS, and is capable of reducing the virus to undetectable levels, but is not a cure and is hampered by issues such as cost, adherence to medication treatment plan and social stigma.

To reduce reliance on ART, the Yerkes, Emory and Institut Pasteur research team worked with 16 SIV-positive, ART-treated rhesus macaques. In most nonhuman primates (NHPs), including rhesus macaques, untreated SIV infection progresses to AIDS-like disease and generates natural killer (NK) cells with impaired functionality. In contrast, natural primate hosts of SIV do not progress to AIDS-like disease. Determining why natural hosts do not progress or how to stop the progression is a critical step in halting HIV in humans.

The researchers compared ART-only treated animals with animals that received ART, IL-21 and IFN-alpha to evaluate how the ART plus combination immunotherapy affected the amount of virus in the animals’ tissues.  

“Our results indicate ART plus combo-treated rhesus monkeys showed enhanced antiviral NK cell responses,” says first author Justin Harper, PhD, a senior research specialist and manager of the Paiardini research lab. “These robust NK cell responses helped clear cells in the lymph nodes, which are known for harboring the virus and enabling its replication and, therefore, the virus’ persistence. Targeting areas where the virus seeks refuge and knowing how to limit replication facilitate controlling HIV.”

HIV treatment has historically focused on the role of T cells in immunity, so harnessing NK cells opens up different avenues.

Mirko Paiardini, PhD

“This proof-of-concept study in rhesus monkeys, which progress to AIDS-like disease in the absence of ART, demonstrates how certain NK cell activities can contribute to controlling the virus,” says Mirko Paiardini, PhD, an associate professor of pathology and laboratory Medicine at Emory University and a researcher at Yerkes. “This opens the door to designing additional treatment strategies to induce SIV and HIV remission in the absence of ART, and, ultimately, reducing the burden HIV is to individuals, families and the world.”

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Posted on by Quinn Eastman in Immunology Leave a comment