Our latest study is about an immunocompromised patient with persistent COVID ➡️ treated with remdesivir but developed resistant mutation ➡️ was then cured by monoclonal Ab cocktail. Study by @gandhisk@sneakyvirus1@epidememeology@marioph13 et al. (1/)
This patient received a course of rituximab (B cell depleting Ab) and bendamustine (chemo agent) for the treatment of Stage IV Non-Hodgkin's lymphoma. As a result, patient had extremely low number of T cells and low lymphocyte counts overall. Analysis by @peowenlu (2/)
So when she was infected with SARS-CoV-2, she was unable to clear the virus for over 150 days. She developed persistent fever, anosmia and ground glass opacities in her lungs. Her viral load stayed high until the remdesivir treatment. (3/)
Remdesivir initially brought her viral load down but this did not last for long. Viral load came up during the course of remdesivir treatment (see shaded gray timeline). (4/)
Why did the virus rebound during the remdesivir treatment? To get at this question, genome of the virus was sequenced. We found an intriguing mutation in the nsp12 gene, E802D, that appeared during the drug treatment. (5/)
Nsp12 is a key component of the RNA-dependent RNA polymerase responsible for viral replication and transcription. Fortunately for us, a prior study already found that nsp12 E802D confers resistance to remdesivir in an in vitro selection experiment. (6/) journals.plos.org/plospathogens/…
Since the genome of the patient’s virus contained many other mutations, we needed to know if the nsp12 E802D mutation was sufficient to confer remdesivir resistance. @Marioph13 heroically synthesized E802D mutant and showed that it’s indeed the case. (7/)
We speculate that the nsp12 E802D mutation distorts the active site in a way that either 1) enables it to exclude remdesivir or 2) alleviates the steric clash mediated by S861, bypassing remdesivir-mediated chain termination. Insights from Anna Pyle and Wenshuai Wang 👇🏽 (8/)
How frequent is the nsp12 E802D or any other substitutions at 802? Luckily very rare. Only 122 (0.003%) and 270 (0.007%), respectively, of the 4.1M genome sequences obtained from patient isolates in the @GISAID database have such mutations. (9/)
This is likely because introducing these mutations to the nsp12 make the virus less fit to replicate in the absence of remdesivir. (10/)
Since the patient was unable to control the virus, the doctors gave her a monoclonal antibody cocktail, casirivimab/imdevimab. Remarkably, her viral titers went down, along with anosmia! Interesting correlation btw clearance of persistent virus and gain of sense of smell 🤔 (11/)
With the clearance of the virus, ground glass opacities also disappeared, along with diminished inflammatory signatures. (12/)
This study illustrates that in this immunocompromised person, endogenous immune responses were unable to control the virus, and that remdesivir resistance arose while on treatment. Monoclonal Abs were effective in clearing persistent virus and restoring sense of smell. (13/)
Another point to highlight is that other than fever and anosmia, this patient was able to tolerate high viral burden for months. Perhaps the impaired adaptive immunity contributed to a disease tolerance phenotype? (14/)
As always, this was a heroic effort by many. In addition to the 4 lead authors, many others contributed incl @peowenlu@WilenLab@GreningerLab@wade_schulz and Albert Ko. Special thank you to the members of @NathanGrubaugh for help and advice 🙏🏼 (end)
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Introducing BEACON (Bioactive Enhanced Adjuvant Chemokine Oligonucleotide Nanoparticles) to stimulate mucosal immune responses against genital #HSV infection. Awesome work led by @sachinbhag, who designed and developed BEACON to guide T and B cells (1/) biorxiv.org/content/10.110…
The BEACON nanoparticle is composed of CpG ODN (TLR9 agonist) and CXCL9 (chemokine). When applied to the vaginal mucosa, the recruitment of antiviral T cells is achieved with minimal local inflammation - much more potent than CpG or CXCL9 separately. (2/)
Intramuscular vaccines do not promote mucosal immunity. BEACON can be used as a local adjuvant to boost HSV-2 gD- or gB-specific T and B cells, preventing not only disease/death but also blocking viral load in both vaginal tissue and dorsal root ganglia (🚫latency)(3/)👇🏼
A fascinating new study by Vishnu Shankar et al. @stanfordimmuno shows that oxidative stress is a shared characteristic of ME/CFS and Long COVID in lymphocytes due to inability to clear reactive oxygen species. This happens in sex-specific manner. (1/) pnas.org/doi/abs/10.107…
Females show higher mtROS levels and insufficient antioxidant levels, while males show mitochondrial lipid oxidative damage. While the reason for this is unclear, it may explain the sex differences in lymphocyte dysfunction we see in PAIS in general. (2/) science.org/doi/10.1126/sc…
ROS-targeting therapies were tested. Metformin treatment in vitro showed some impact on CD4 T cell proliferation. I suspect that other therapies to induce autophagy/mitophagy might also benefit restoration of T cell phenotype. #LowDoseRapamycin 👇🏼 (3/) polybio.org/projects/long-…
Published today! Victoria Bastos, @KerrieGreene_ et al found two distinct immunotypes of ME/CFS based on the cerebrospinal fluid analysis. Great collaboration with @MBVanElzakker @microbeminded2 and the Bragée clinic in Sweden. (1/) academic.oup.com/jimmunol/artic…
This is perfect timing as Victoria will present these data at the @polybioRF symposium today. (2/)
Based on cerebrospinal fluid cytokines, we identified two clusters of ME/CFS patients. Cluster 1 had elevated matrix metalloproteinases & many cytokines compared to cluster 2. Other than older age (Cluster 1), clinical presentation of these clusters was similar. (3/)
Published today📣
Our nasal booster in the "Prime & Spike" vaccine works without adjuvants (which are needed to induce adaptive immunity but also cause inflammation). @Kwon_Dongil @tianyangmao @BenIsraelow et al. asked how this is possible. (1/) nature.com/articles/s4159…
Prime & Spike is a vaccine strategy that leverages preexisting immunity primed by conventional vaccines to elicit mucosal IgA and T cell responses that prevent COVID infection and transmission in rodents. The nasal booster is simply the spike protein (2/) science.org/doi/10.1126/sc…
Our new study shows that the nasal spike protein booster converts lymph node memory B cells into IgA-secreting cells in the lung with the help of memory CD4 T cells. Ag-specific CD4 T cells replace all the necessary functions of adjuvants without nonspecific inflammation! (3/)
This prospective observational study led by @connorbgrady @bornali_27 @SilvaJ_C @hmkyale examined the impact of the primary COVID-19 vaccination on the symptoms and immune signatures of 16 people with #longCOVID. Here is what we found 👇🏼 (1/)
This study asked: Does COVID vaccination improve symptoms of long COVID? If so, is the improvement due to robust T and B cell responses leading to the clearance of the viral reservoir? If not, is there an immune feature that predicts worsening of LC? (2/)
The self-reported impact of vaccination was variable. Of the 16 long COVID patients, 10 felt better, 3 had no change, and 3 had worse health (1 hospitalized) 12 weeks after vaccination. Both physical and social effects of symptom burden appeared to decrease after vaccination. (3/)
Our preprint on post-vaccination syndrome is out. We studied immune signatures and examined spike protein in the blood of people who have developed chronic illnesses after COVID-19 vaccination. (1/) medrxiv.org/content/10.110…
Vaccines have saved countless lives and inspired me to become an immunologist. While generally safe, some people experience adverse effects, including Post-Vaccination Syndrome (PVS). Studying PVS is crucial for improving patient care and enhancing vaccine safety & acceptance. (2/) pubmed.ncbi.nlm.nih.gov/37986769/