Two items relevant to long COVID

One of the tricky issues in studying in long COVID is: how widely do researchers cast their net? Initial reports acknowledged that people who were hospitalized and in intensive care may take a while to get back on their feet. But the number of people who had SARS-CoV-2 infections and were NOT hospitalized, yet experienced lingering symptoms, may be greater. A recent report from the United Kingdom, published in PLOS Medicine, studied more than Read more

All your environmental chemicals belong in the exposome

Emory team wanted to develop a standard low-volume approach that would avoid multiple processing steps, which can lead to loss of material, variable recovery, and the potential for Read more

Signature of success for an HIV vaccine?

Efforts to produce a vaccine against HIV/AIDS have been sustained for more than a decade by a single, modest success: the RV144 clinical trial in Thailand, whose results were reported in 2009. Now Emory, Harvard and Case Western Reserve scientists have identified a gene activity signature that may explain why the vaccine regimen in the RV144 study was protective in some individuals, while other HIV vaccine studies were not successful. The researchers think that this signature, Read more

Mark Mulligan

Zika immunology from returned travelers

At the American Association for the Advancement of Science meeting in Boston last weekend, Emory Vaccine Center researcher Mark Mulligan presented some limited findings on immune responses in Zika-infected humans, who were returned US travelers or expatriates.

The results were intriguing, despite the small number of study participants: five, two of whom were pregnant. Detailed information has not been available about immune responses against Zika in humans, especially T cell responses.

Highlights from Mulligan’s abstract:

*All five seemed to have a hole in their immune systems – functional antiviral “killer” CD8 T cells were rare, despite activation of CD8 T cells in general and strong responses from other cell types.

*Cross-reactive immune responses, based on previous exposure to dengue and/or yellow fever vaccine, may have blunted Zika’s peak.

*”Even with prolonged maternal viremia, both pregnancies resulted in live births of apparently healthy babies.” Read more

Posted on by Quinn Eastman in Immunology Leave a comment

Mulligan WABE interview on Ebola vaccine research

A recent WABE “Closer Look” interview with Mark Mulligan, executive director of the Emory Vaccine Center’s Hope Clinic, covers a lot of ground. It starts off with a segment — also aired on Marketplace — from reporter Michell Eloy, who visited the Hope Clinic’s lab. We hear a machine processing blood samples from a study testing an experimental Ebola vaccine and a roundup of Ebola vaccine developments.

We also hear from Carl Davis, postdoc in Rafi Ahmed’s lab, who is part of the DARPA-funded team research project studying the utility of antibodies from Ebola survivors. [Other recent news on this topic from The Scientist.]

Then, reporters Rose Scott and Jim Burress discuss several different Ebola vaccines with Mulligan. One is based on chimpanzee adenovirus, was tested at the Hope Clinic and elsewhere in the USA and the UK, and then in Liberia. While this vaccine was safe and it appears to stimulate the immune system appropriately, the outbreak fizzled out (a good thing!) before it was possible to tell if the vaccine protected people from Ebola infection. Read more

Posted on by Quinn Eastman in Immunology Leave a comment

Key to universal flu vaccine: embrace the unfamiliar

Vaccine researchers have developed a strategy aimed at generating broadly cross-reactive antibodies against the influenza virus: embrace the unfamiliar.

In recent years, researchers interested in a “universal flu vaccine” identified a region of the viral hemagglutinin protein called the stem or stalk, which doesn’t mutate and change as much as other regions and could be the basis for a vaccine that is protective against a variety of flu strains.

In an Emory Vaccine Center study, human volunteers immunized against the avian flu virus H5N1 readily developed antibodies against the stem region of the viral hemagglutinin protein. In contrast, those immunized with standard seasonal trivalent vaccines did not, instead developing most of their antibodies against the more variable head region. H5N1, regarded as a potential pandemic strain, is not currently circulating in the United States and the volunteers had not been exposed to it before.

The results were published Monday, August 25 in PNAS.

The key to having volunteers’ bodies produce antibodies against the stem region seemed to be their immune systems’ unfamiliarity with the H5N1 type of virus, says lead author Ali Ellebedy, PhD, postdoctoral fellow in the laboratory of Rafi Ahmed, PhD, director of Emory Vaccine Center and a Georgia Research Alliance Eminent Scholar.

Note: for a counterpoint, check out this 2013 Science Translational Medicine paper on how vaccination that induces anti-stem antibodies contributes to enhanced respiratory disease in pigs.

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Posted on by Quinn Eastman in Immunology Leave a comment