Josh Obar
obarlab.bsky.social
Josh Obar
@obarlab.bsky.social
Associate Professor, Geisel School of Medicine at Dartmouth College, Department of Microbiology & Immunology; Laboratory of Antifungal & Antiviral Immunity (Aspergillus fumigatus / Influenza A virus)
Pinned
🚨 Updated preprint for our first manuscript with
@aolive.bsky.social looking at why alveolar macrophages drive strong type I IFN responses after TLR2 activation; we uncovered a surprising role for and mitochondria ROS and MAVS signaling - find out more here: www.biorxiv.org/content/10.1...
| bioRxiv
bioRxiv - the preprint server for biology, operated by Cold Spring Harbor Laboratory, a research and educational institution
www.biorxiv.org
Reposted by Josh Obar
Two Harvard economists forecast the impact of the administration’s proposed NIH budget cuts- stunning losses in new therapies, life expectancy, and economic output with a “social cost 16 times greater than the savings the administration is attempting to achieve."

jamanetwork.com/journals/jam...
Cutting the NIH—The $8 Trillion Health Care Catastrophe
This JAMA Forum discusses the recent budget cuts to National Institutes of Health (NIH), the effects of these cuts on scientific research and health of individuals in the US, and the prospects for cha...
jamanetwork.com
May 29, 2025 at 9:20 PM
Reposted by Josh Obar
‘Cell type–specific efferocytosis determines functional plasticity of alveolar macrophages’

www.science.org/doi/10.1126/...
Cell type–specific efferocytosis determines functional plasticity of alveolar macrophages
MPO activates an immunometabolic rheostat to restrict the functional plasticity of macrophages in favor of proresolving properties.
www.science.org
May 5, 2025 at 7:57 AM
Interesting preprint looking at the role of MAVS in maintaining mitochondrial health!
MAVS Orchestrates a Potent IFN-independent Antiviral Immunity by Preserving Mitochondrial Integrity https://www.biorxiv.org/content/10.1101/2025.04.28.651145v1
May 2, 2025 at 10:17 AM
🤖 The middle kid’s FIRST Lego Robotics team had the opportunity to compete at the FIRST Robotics World Championship last week in Houston. He had a blast. Great work making their kids. 🤖
May 2, 2025 at 1:17 AM
🚨 Updated preprint for our first manuscript with
@aolive.bsky.social looking at why alveolar macrophages drive strong type I IFN responses after TLR2 activation; we uncovered a surprising role for and mitochondria ROS and MAVS signaling - find out more here: www.biorxiv.org/content/10.1...
| bioRxiv
bioRxiv - the preprint server for biology, operated by Cold Spring Harbor Laboratory, a research and educational institution
www.biorxiv.org
May 1, 2025 at 4:02 PM
Reposted by Josh Obar
Excited to share our latest study
@cp-immunity.bsky.social. Heartfelt thanks to the editorial and review teams , to my co-first @yeungadventures.bsky.social, our co-authors, and to @khannakm.bsky.social
for his outstanding mentorship throughout! Pls read/share!👇
www.cell.com/immunity/ful...
Nerve- and airway-associated interstitial macrophages mitigate SARS-CoV-2 pathogenesis via type I interferon signaling
The local immunoregulatory mechanisms that safeguard the host from excessive lung infection inflammation remain unclear. Yeung, Yokota et al. uncover the essential role of nerve- and airway-associated...
www.cell.com
April 25, 2025 at 2:38 PM
Reposted by Josh Obar
Excited to share that our story on S. aureus antagonism by Malassezia is live today in Current Biology! The paper has changed a lot since the preprint with the very exciting addition of having identified the antimicrobial effector generated by M. sympodialis.

authors.elsevier.com/c/1kwzj3QW8S...
authors.elsevier.com
April 14, 2025 at 5:33 PM
Last week Alex Rapp successfully defended his PhD thesis on the role of mycoviruses in Aspergillus regulating antifungal immunity.
April 14, 2025 at 6:55 PM
Reposted by Josh Obar
We are thrilled to share our new manuscript @science.org , in which we uncovers a critical role for macrophage peroxisomes in lung repair after viral infection. Could targeting peroxisomes be the key to mitigating long COVID?! www.science.org/doi/10.1126/...
Macrophage peroxisomes guide alveolar regeneration and limit SARS-CoV-2 tissue sequelae
Peroxisomes are vital but often overlooked metabolic organelles. We found that excessive interferon signaling remodeled macrophage peroxisomes. This loss of peroxisomes impaired inflammation resolutio...
www.science.org
March 6, 2025 at 8:35 PM
Reposted by Josh Obar
Just published @science.org
A basis—lung inflammation—for #LongCovid (PASC) in the experimental model, and a potential therapy
[driven by alveolar macrophages and loss of their peroxisomes (Figure)]
www.science.org/doi/10.1126/...
www.science.org/doi/10.1126/...
March 6, 2025 at 7:00 PM
Reposted by Josh Obar
By @katherinejwu.com

"The NIH... supported 99 percent of the drugs approved in the U.S. from 2010 to 2019. The agency has had a hand in “nearly all of our major medical breakthroughs over the past several decades,”

The NIH is in a struggle for its (and our) lives. This is existential to America:
Inside the Collapse at NIH
Administration officials pressured NIH to avoid clear advice from the agency’s own lawyers to restart grant funding now.
www.theatlantic.com
February 27, 2025 at 5:29 PM
Happy to have contributed to this exciting paper from Dr Yina Huang’s laboratory. Congratulations to her lab and everyone involved!
February 28, 2025 at 10:28 AM
Reposted by Josh Obar
NIH funding creates medicines, jobs and economic growth
February 24, 2025 at 12:56 PM
Reposted by Josh Obar
Excited to share our latest preprint! We find that DCs undergo heterogeneous cell death- either pyroptosis or apoptosis upon bacterial blockade of host translation- to restrict Legionella infection. Congrats to my PhD student @vvazquez.bsky.social & co-authors! Check out his bluetorial 🧵 below! 👇
February 21, 2025 at 6:43 PM
Reposted by Josh Obar
Latest from the Watson lab-- mice carrying a mutation in mitochondrial DNA polymerase are susceptible to TB, experiencing high bacterial burdens and extensive necrosis in the lung. Yet another link between mitochondrial health and antimycobacterial immunity.
journals.asm.org/doi/10.1128/...
Necrosis drives susceptibility to Mycobacterium tuberculosis in PolgD257A mutator mice | Infection and Immunity
Defects in mitochondria are associated with a variety of human diseases and metabolic disorders (1). Inherited mitochondrial diseases, caused by mutations harbored in the mitochondrial genome (mtDNA) or in nuclear-encoded mitochondrial genes, lead to devastating neurodegenerative and cardiovascular disorders (2). They are also frequently associated with chronic inflammation and autoimmunity. Type I interferonopathies, for example, are often caused by mutations that result in aberrant release of mitochondrial nucleic acids and chronic engagement of cytosolic nucleic acid sensing (3–5). Consistent with important links between mitochondrial health and immune function, patients with mitochondrial mutations are prone to frequent viral and bacterial infections that are often severe (6, 7). They can also suffer from systemic inflammatory response syndrome caused by hyperinflammation in the absence of infection (8). Furthermore, human single nucleotide polymorphisms (SNPs) in mitochondrial genes have been shown to confer susceptibility to several bacterial pathogens, including Salmonella enterica serovar Typhi (9), Listeria monocytogenes (10), and Mycobacterium leprae (11). Despite clear connections between mitochondria and immunity, the mechanistic contributions of specific mitochondrial-associated mutations in driving susceptibility to infection remain unclear.
journals.asm.org
February 19, 2025 at 8:01 PM
🎉I am excited to say that I was promoted to Professor with Tenure at Geisel School of Medicine at Dartmouth. Thank you to all my current and former trainees that have made the lab a success. Special thanks to Robb Cramer for getting me interested in fungal immunology and his continued support!
February 6, 2025 at 1:34 PM
Reposted by Josh Obar
🚨 Delighted to share our paper defining a new role for IL-6 in TB. 🚨

We used genetic variation to show *reduced* IL-6 signalling is causally associated with *lower* risk of TB.

Lead author @gushamilton.bsky.social

#TBSky #IDSky #ImmunoSky www.thelancet.com/journals/lan...
Thread 👇 (1/8)
Altered IL-6 signalling and risk of tuberculosis: a multi-ancestry mendelian randomisation study
Our findings propose a causal relationship between reduced IL-6 signalling and lower risk of tuberculosis, akin to the effect seen in other IL-6 mediated diseases. This study suggests that IL-6 antago...
www.thelancet.com
November 21, 2024 at 10:30 AM