Tag: 2022

Inflammation and autoreactivity define a discrete subset of patients with post-acute sequelae of COVID-19, or long-COVID

Abstract:

While significant attention has been paid to the immunologic determinants of disease states associated with COVID-19, their contributions to post-acute sequelae of COVID-19 (PASC) remain less clear. Due to the wide array of PASC presentations, it is critical to understand if specific features of the disease are associated with discrete immune processes, and whether those processes may be therapeutically targeted. To this end, we performed wide immunologic and serological characterization of patients in the early recovery phase of COVID-19 across a breadth of symptomatic presentations.

Using high-parameter proteomics screening and applied machine learning (ML), we identify clear signatures of immunologic activity between PASC patients and uncomplicated recovery, dominated by inflammatory cytokine signaling, neutrophil activity, and markers of cell death. Consistent with disease complexity, heterogeneity in plasma profiling reveals distinct PASC subsets with striking divergence in these ongoing inflammatory processes, here termed plasma quiescent (plaq) and inflammatory (infl) PASC.

In addition to elevated inflammatory blood proteomics, inflPASC patients display positive clinical tests of acute inflammation including C-reactive protein and fibrinogen, increased B cell activity with extrafollicular involvement coupled with elevated targeting of viral nucleocapsid protein and clinical autoreactivity. Further, the unique plasma signatures of PASC patients allowed for the creation of refined models with high sensitivity and specificity for the positive identification of inflPASC with a streamlined assessment of 12 blood markers. Additionally, refined ML modeling highlights the unexpected significance of several markers of potential diagnostic or therapeutic use for PASC in general, including the peptide hormone, epiregulin.

In all, this work identifies clear biological signatures of PASC with potential diagnostic and therapeutic potential and establishes clear disease subtypes that are both easily identifiable and highly relevant to ongoing efforts in both therapeutic targeting and epidemiological investigation of this highly complex disease.

Source: Matthew Woodruff, Kevin S Bonham, Fabliha A Anam, Tiffany Walker, Yusho Ishii, Candice Y Kaminski, Martin Runnstrom, Alexander Truong, Adviteeya Dixit, Jenny Han, Richard Ramonell, Natalie S. Haddad, Mark Rudoloph, Arezou Khosroshahi, Scott A Jenks, F. Eun-Hyung Lee, Ignacio Sanz. Inflammation and autoreactivity define a discrete subset of patients with post-acute sequelae of COVID-19, or long-COVID. medRxiv 2021.09.21.21263845; doi: https://doi.org/10.1101/2021.09.21.21263845.  (Full text available as PDF file)

Effects of SARS-CoV-2 Infection on Attention, Memory, and Sensorimotor Performance

Abstract:

Background: Recovery after SARS-CoV-2 infection is extremely variable, with some individuals recovering quickly, and others experiencing persistent long-term symptoms or developing new symptoms after the acute phase of infection, including fatigue, poor concentration, impaired attention, or memory deficits. Many existing studies reporting cognitive deficits associated with SARS-CoV-2 infection are limited by the exclusive use of self-reported measures or a lack of adequate comparison groups.

Methods: Forty-five participants, ages 18-70, (11 Long-COVID, 14 COVID, and 20 No-COVID) underwent behavioral testing with the NIH Toolbox Neuro-Quality of Life survey and selected psychometric tests, including a flanker interference task and the d2 Test of Attention.

Results: We found greater self-reported anxiety, apathy, fatigue, emotional dyscontrol, sleep disturbance and cognitive dysfunction in COVID compared No-COVID groups. After categorizing COVID patients according to self-reported concentration problems, we observed declining performance patterns in multiple attention measures across No-COVID controls, COVID and Long-COVID groups. COVID participants, compared to No-COVID controls, exhibited worse performance on NIH Toolbox assessments, including the Eriksen Flanker, Nine-Hole Pegboard and Auditory Verbal Learning tests.

Conclusion: This study provides convergent evidence that previous SARS-CoV-2 infection is associated with impairments in sustained attention, processing speed, self-reported fatigue and concentration. The finding that some patients have cognitive and visuomotor dysfunction in the absence of self-reported problems suggests that SARS-CoV-2 infection can have unexpected and persistent subclinical consequences.

Source: O’Connor EE, Rednam N, O’Brien R, O’Brien S, Rock P, Levine A, Zeffiro TA. Effects of SARS-CoV-2 Infection on Attention, Memory, and Sensorimotor Performance. medRxiv [Preprint]. 2022 Sep 23:2022.09.22.22280222. doi: 10.1101/2022.09.22.22280222. PMID: 36172134; PMCID: PMC9516858. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9516858/ (Full text)

COVID-19 immunopathology: From acute diseases to chronic sequelae

Abstract:

The clinical manifestation of coronavirus disease 2019 (COVID-19) mainly targets the lung as a primary affected organ, which is also a critical site of immune cell activation by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, recent reports also suggest the involvement of extrapulmonary tissues in COVID-19 pathology.

The interplay of both innate and adaptive immune responses is key to COVID-19 management. As a result, a robust innate immune response provides the first line of defense, concomitantly, adaptive immunity neutralizes the infection and builds memory for long-term protection. However, dysregulated immunity, both innate and adaptive, can skew towards immunopathology both in acute and chronic cases.

Here we have summarized some of the recent findings that provide critical insight into the immunopathology caused by SARS-CoV-2, in acute and post-acute cases. Finally, we further discuss some of the immunomodulatory drugs in preclinical and clinical trials for dampening the immunopathology caused by COVID-19.

Source: Arish M, Qian W, Narasimhan H, Sun J. COVID-19 immunopathology: From acute diseases to chronic sequelae. J Med Virol. 2022 Sep 3. doi: 10.1002/jmv.28122. Epub ahead of print. PMID: 36056655. https://onlinelibrary.wiley.com/doi/10.1002/jmv.28122 (Full text)

Proteomics of fibrin amyloid microclots in long COVID/post-acute sequelae of COVID-19 (PASC) shows many entrapped pro-inflammatory molecules that may also contribute to a failed fibrinolytic system

Abstract:

Background: Post-acute sequelae of COVID-19 (PASC), also now known as long COVID, has become a major global health and economic burden. Previously, we provided evidence that there is a significant insoluble fibrin amyloid microclot load in the circulation of individuals with long COVID, and that these microclots entrap a substantial number of inflammatory molecules, including those that might prevent clot breakdown. Scientifically, the most challenging aspect of this debilitating condition is that traditional pathology tests such as a serum CRP (C-reactive protein) may not show any significant abnormal inflammatory markers, albeit these tests measure only the soluble inflammatory molecules. Elevated, or abnormal soluble biomarkers such as IL-6, D-Dimer or fibrinogen indicate an increased risk for thrombosis or a host immune response in COVID-19. The absence of biomarkers in standard pathology tests, result in a significant amount of confusion for patients and clinicians, as patients are extremely sick or even bed-ridden but with no regular identifiable reason for their disease. Biomarkers that are currently available cannot detect the molecules present in the microclots we identified and are therefore unable to confirm their presence or the mechanisms that drive their formation.

Methods: Here we analysed the protein content of double-digested microclots of 99 long COVID patients and 29 healthy controls. The patients suffering from long COVID reported their symptoms through a questionnaire completed by themselves or their attending physician.

Results: Our long COVID cohort’s symptoms were found to be in line with global findings, where the most prevalent symptoms were constant fatigue (74%,) cognitive impairment (71%) and depression and anxiety (30%). Our most noteworthy findings were a reduced level of plasma Kallikrein compared to our controls, an increased level of platelet factor 4 (PF4) von Willebrand factor (VWF), and a marginally increased level of α-2 antiplasmin (α-2-AP). We also found a significant presence of antibodies entrapped inside these microclots.

Conclusion: Our results confirm the presence of pro-inflammatory molecules that may also contribute to a failed fibrinolysis phenomenon, which could possibly explain why individuals with long COVID suffer from chronic fatigue, dyspnoea, or cognitive impairment. In addition, significant platelet hyperactivation was noted. Hyperactivation will result in the granular content of platelets being shed into the circulation, including PF4. Overall, our results provide further evidence of both a failed fibrinolytic system in long COVID/PASC and the entrapment of many proteins whose presence might otherwise go unrecorded. These findings might have significant implications for individuals with pre-existing comorbidities, including cardiovascular disease and type 2 diabetes.

Source: Kruger A, Vlok M, Turner S, Venter C, Laubscher GJ, Kell DB, Pretorius E. Proteomics of fibrin amyloid microclots in long COVID/post-acute sequelae of COVID-19 (PASC) shows many entrapped pro-inflammatory molecules that may also contribute to a failed fibrinolytic system. Cardiovasc Diabetol. 2022 Sep 21;21(1):190. doi: 10.1186/s12933-022-01623-4. PMID: 36131342; PMCID: PMC9491257. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9491257/ (Full text)

Post-COVID-19 syndrome: retinal microcirculation as a potential marker for chronic fatigue

Abstract:

Post-COVID-19 syndrome (PCS) summarizes persisting sequelae after infection with the severe-acute-respiratory-syndrome-Coronavirus-2 (SARS-CoV-2). PCS can affect patients of all covid-19 disease severities. As previous studies revealed impaired blood flow as a provoking factor for triggering PCS, it was the aim of the present study to investigate a potential association of self-reported chronic fatigue and retinal microcirculation in patients with PCS, potentially indicating an objective biomarker.

A prospective study was performed, including 201 subjects: 173 patients with PCS and 28 controls. Retinal microcirculation was visualized by OCT-Angiography (OCT-A) and quantified by the Erlangen-Angio-Tool as macula and peripapillary vessel density (VD). Chronic Fatigue (CF) was assessed with the variables ‘Bell score’, age and gender. The VD in the superficial vascular plexus (SVP), intermediate capillary plexus (ICP) and deep capillary plexus (DCP) were analyzed considering the repetitions (12 times). Taking in account of such repetitions a mixed model was performed to detect possible differences in the least square means between different groups of analysis.

An age effect on VD was observed between patients and controls (p<0.0001). Gender analysis yielded that women with PCS showed lower VD levels in SVP compared to male patients (p=0.0015). The PCS patients showed significantly lower VD of ICP as compared to the controls (p=0.0001, [CI: 0.32; 1]). Moreover, considering PCS patients, the mixed model reveals a significant difference between chronic fatigue (CF) and without CF in VD of SVP (p=0.0033, [CI: -4.5; -0.92]). The model included age, gender and the variable ‘Bell score’, representing a subjective marker for CF. Consequently, the retinal microcirculation might be an objective biomarker in subjective-reported chronic fatigue of patients with PCS.

Source: Sarah Schlick, Marianna Lucio, Alexander Bartsch, Adam Skornia, Jakob Hoffmanns, Charlotte Szewczykowski, Thora Schröder, Franziska Raith, Lennart Rogge, Felix Heltmann, Michael Moritz, Lorenz Beitlich, Julia Schottenhamml, Martin Herrmann, Thomas Harrer, Marion Ganslmayer, Friedrich E. Kruse, Robert Lämmer, Christian Mardin, Bettina Hohberger. Post-COVID-19 syndrome: retinal microcirculation as a potential marker for chronic fatigue. medRxiv 2022.09.23.22280264; doi: https://doi.org/10.1101/2022.09.23.22280264 https://www.medrxiv.org/content/10.1101/2022.09.23.22280264v1.full-text (Full text)

Long Covid and Apheresis – Where are we Standing?

Abstract:

A continual increase in cases of Long Covid constitutes a medical and socioeconomic challenge to health systems around the globe. While the true extent of this problem cannot yet be fully evaluated, recent data suggests that up to 20% of people with confirmed with SARS-CoV-2 suffer from clinically relevant symptoms of Long Covid several weeks to months after the acute phase. The clinical presentation is highly variable with the main symptoms being chronic fatigue, dyspnea and cognitive symptoms. Extracorporeal apheresis has been suggested to alleviate symptoms of Long Covid. Thus, numerous patients are currently treated with apheresis. However, at present there is no data from randomized controlled trials available to confirm the efficacy. Therefore, physicians rely on the experience of practitioners and centers performing this treatment. Here, we summarize clinical experience on extracorporeal apheresis in patients with Long Covid from centers across Germany.

Source: Steenblock C, Walther R, Tselmin S, Jarzebska N, Voit-Bak K, Toepfner N, Siepmann T, Passauer J, Hugo C, Wintermann G, Julius U, Babir M, Khan TZ, Puhan MA, Straube R, Hohenstein B, Bornstein SR, Rodionov R. Long Covid and Apheresis – Where are we Standing? Horm Metab Res. 2022 Sep 16. doi: 10.1055/a-1945-9694. Epub ahead of print. PMID: 36113501.  https://pubmed.ncbi.nlm.nih.gov/36113501/

Differential diagnosis and pathogenesis of the neurological signs and symptoms in COVID-19 and long-COVID syndrome

Abstract:

Neurological features have now been reported very frequently in the ongoing COVID-19 pandemic caused by SARS-CoV-2. The neurological deficits associated features are observed in both acute and chronic stages of COVID-19 and they appear to overlap with wide-ranging symptoms that can be attributed to being of non-neural origins, thus obscuring the definitive diagnosis of neuro-COVID.

The pathogenetic factors acting in concert to cause neuronal injury are now emerging, with SARS-CoV-2 directly affecting the brain coupled with the neuroinflammatory factors have been implicated in the causation of disabilities in acute COVID-19 and patients with Long-COVID syndrome. As the differentiation between a neural origin and other organ-based causation of a particular neurological feature is of prognostic significance, it implores a course of action to this covert, yet important neurological challenge.

Source: Baig AM. Differential diagnosis and pathogenesis of the neurological signs and symptoms in COVID-19 and long-COVID syndrome. CNS Neurosci Ther. 2022 Sep 19. doi: 10.1111/cns.13957. Epub ahead of print. PMID: 36117492. https://onlinelibrary.wiley.com/doi/10.1111/cns.13957 (Full text)

Memory alterations after COVID-19 infection: a systematic review

Abstract:

SARS-CoV-2 infection has a wide range of both acute and long-term symptoms. Memory alterations have been frequently reported in studies that explore cognition. The main objective of the systematic review is to update and further analyze the existing evidence of objective memory impairments in long-COVID-19 considering sample and study design characteristics, as well as to explore associations between memory performance and their epidemiological, clinical, and pathological features.

A total of 13 studies were identified by searching in PubMed, Web of Science, and PsycInfo databases up to May 6, 2022. Most studies evaluated verbal component of memory in the short-term and long-term recall up to 30 min and mainly performed a single assessment completed at 4-6 months after the infection. The samples mainly consisted of middle-aged adults that required hospitalization. Samples were not stratified by sex, age, and severity.

Poor verbal learning was reported in most cases (6-58%), followed by deficits in long-term (4-58%) and short-term (4-37%) verbal memory. Visuospatial component of memory was studied less than verbal component, showing impairment of long-term retention of visual items (10-49%). COVID-19 severity in the acute stage was not systematically associated with poor memory performance. Verbal memory deficits were associated with anxiety and depression.

The existing literature on objective memory assessment in long-COVID suggests further research is warranted to confirm memory dysfunction in association with epidemiological, pathological, and clinical factors, using both verbal and visuospatial tests, and exploring in deep long-term memory deficits.

Source: Llana T, Zorzo C, Mendez-Lopez M, Mendez M. Memory alterations after COVID-19 infection: a systematic review. Appl Neuropsychol Adult. 2022 Sep 15:1-14. doi: 10.1080/23279095.2022.2123739. Epub ahead of print. PMID: 36108666.  https://pubmed.ncbi.nlm.nih.gov/36108666/

Targeting endothelial dysfunction and oxidative stress in Long-COVID

Comment:

We thank Dr. Hsu and Dr. Lai for their interest in our work on COVID-19 and Long-COVID.

We fully agree with them on the fact that several factors need to be pondered in order to evaluate the risk of developing Long-COVID , . However, we respectfully believe that these considerations are not pertinent to our study . Indeed, we designed the LINCOLN (l-Arginine and Vitamin C improves Long-COVID) survey to determine whether a supplementation combining l-Arginine (to improve endothelial function) and Vitamin C (to reduce oxidation) could have favorable effects in patients with Long-COVID . Thus, in our study we did not assess the risk of developing Long-COVID; in fact, as clearly specified in our article, all the enrolled patients had Long-COVID when the survey was administered. Nevertheless, potential differences in health conditions between the group that had received l-Arginine + Vitamin C and the group that had received the alternative treatment were ruled out by their family physicians. When comparing the two groups, we did not observe any significant difference in terms of age, sex, hospitalization due to COVID-19, and time from SARS-Cov-2 negativization. Moreover, bearing in mind the limitations that all surveys have, we had concluded our article stating that further dedicated interventional studies were warranted to endorse our findings.

Of note, we have previously conducted a randomized, double-blind, placebo-controlled, parallel-group, clinical trial testing the effects of l-Arginine oral supplementation in patients hospitalized for COVID-19, demonstrating that this treatment significantly decreases the length of hospitalization and reduces the respiratory support . Additionally, we have identified endothelial exosomes enriched in miR-24 as a reliable biomarker to predict cerebrovascular complications of COVID-19 , corroborating the fundamental role of endothelial dysfunction in the pathobiology of COVID-19 and its clinical sequelae .

Source: Trimarco V, Izzo R, Mone P, Trimarco B, Santulli G. Targeting endothelial dysfunction and oxidative stress in Long-COVID. Pharmacol Res. 2022 Sep 13;184:106451. doi: 10.1016/j.phrs.2022.106451. Epub ahead of print. PMID: 36108875; PMCID: PMC9467917. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9467917/ (Full text)

Low Prevalence of Interferon-α Autoantibodies in People Experiencing Long COVID Symptoms

Abstract:

Interferon (IFN)-specific autoantibodies have been implicated in severe COVID-19 and have been proposed as a potential driver of the persistent symptoms characterizing Long COVID, a type of post-acute sequelae of SARS-CoV-2 infection (PASC). We report than only two of 215 SARS-CoV-2 convalescent participants tested over 394 timepoints, including 121 people experiencing Long COVID symptoms, had detectable IFN-α2 antibodies. Both had been hospitalized during the acute phase of the infection. These data suggest that persistent anti-IFN antibodies, although a potential driver of severe COVID-19, are unlikely to contribute to Long COVID symptoms in the post-acute phase of the infection.

Source: Peluso MJ, Mitchell A, Wang CY, Takahashi S, Hoh R, Tai V, Durstenfeld MS, Hsue PY, Kelly JD, Martin JN, Wilson MR, Greenhouse B, Deeks SG, DeRisi JL, Henrich TJ. Low Prevalence of Interferon-α Autoantibodies in People Experiencing Long COVID Symptoms. J Infect Dis. 2022 Sep 12:jiac372. doi: 10.1093/infdis/jiac372. Epub ahead of print. PMID: 36089700.  https://academic.oup.com/jid/advance-article/doi/10.1093/infdis/jiac372/6696027 (Full text available as PDF file)