Tag: long covid immunology

Autoantigen profiling reveals a shared post-COVID signature in fully recovered and Long COVID patients

Abstract:

Some individuals do not return to baseline health following SARS-CoV-2 infection, leading to a condition known as Long COVID. The underlying pathophysiology of Long COVID remains unknown. Given that autoantibodies have been found to play a role in severity of COVID infection and certain other post-COVID sequelae, their potential role in Long COVID is important to investigate. Here we apply a well-established, unbiased, proteome-wide autoantibody detection technology (PhIP-Seq) to a robustly phenotyped cohort of 121 individuals with Long COVID, 64 individuals with prior COVID-19 who reported full recovery, and 57 pre-COVID controls.

While a distinct autoreactive signature was detected which separates individuals with prior COVID infection from those never exposed to COVID, we did not detect patterns of autoreactivity that separate individuals with Long COVID relative to individuals fully recovered from SARS-CoV-2 infection. These data suggest that there are robust alterations in autoreactive antibody profiles due to infection; however, no association of autoreactive antibodies and Long COVID was apparent by this assay.

Source: Bodansky A, Wang CY, Saxena A, Mitchell A, Takahashi S, Anglin K, Huang B, Hoh R, Lu S, Goldberg SA, Romero J, Tran B, Kirtikar R, Grebe H, So M, Greenhouse B, Durstenfeld MS, Hsue PY, Hellmuth J, Kelly JD, Martin JN, Anderson MS, Deeks SG, Henrich TJ, DeRisi JL, Peluso MJ. Autoantigen profiling reveals a shared post-COVID signature in fully recovered and Long COVID patients. medRxiv [Preprint]. 2023 Feb 9:2023.02.06.23285532. doi: 10.1101/2023.02.06.23285532. PMID: 36798288; PMCID: PMC9934805. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9934805/ (Full text)

Long COVID manifests with T cell dysregulation, inflammation, and an uncoordinated adaptive immune response to SARS-CoV-2

Abstract:

Long COVID (LC), a type of post-acute sequelae of SARS-CoV-2 infection (PASC), occurs after at least 10% of SARS-CoV-2 infections, yet its etiology remains poorly understood. Here, we used multiple “omics” assays (CyTOF, RNAseq, Olink) and serology to deeply characterize both global and SARS-CoV-2-specific immunity from blood of individuals with clear LC and non-LC clinical trajectories, 8 months following infection and prior to receipt of any SARS-CoV-2 vaccine. Our analysis focused on deep phenotyping of T cells, which play important roles in immunity against SARS-CoV-2 yet may also contribute to COVID-19 pathogenesis.

Our findings demonstrate that individuals with LC exhibit systemic inflammation and immune dysregulation. This is evidenced by global differences in T cell subset distribution in ways that imply ongoing immune responses, as well as by sex-specific perturbations in cytolytic subsets. Individuals with LC harbored increased frequencies of CD4+ T cells poised to migrate to inflamed tissues, and exhausted SARS-CoV-2-specific CD8+ T cells. They also harbored significantly higher levels of SARS-CoV-2 antibodies, and in contrast to non-LC individuals, exhibited a mis-coordination between their SARS-CoV-2-specific T and B cell responses.

Collectively, our data suggest that proper crosstalk between the humoral and cellular arms of adaptive immunity has broken down in LC, and that this, perhaps in the context of persistent virus, leads to the immune dysregulation, inflammation, and clinical symptoms associated with this debilitating condition.

Source: Kailin Yin, Michael J. Peluso, Reuben Thomas, Min Gyoung Shin, Jason Neidleman, Xiaoyu Luo, Rebecca Hoh, Khamal Anglin, Beatrice Huang, Urania Argueta, Monica Lopez, Daisy Valdivieso, Kofi Asare, Rania Ibrahim, Ludger Ständker, Scott Lu, Sarah A. Goldberg, Sulggi A. Lee, Kara L. Lynch, J. Daniel Kelly, Jeffrey N. Martin, Jan Münch, Steven G. Deeks, Timothy J. Henrich, Nadia R. Roan. Long COVID manifests with T cell dysregulation, inflammation, and an uncoordinated adaptive immune response to SARS-CoV-2. bioRxiv 2023.02.09.527892; doi: https://doi.org/10.1101/2023.02.09.527892 https://www.biorxiv.org/content/10.1101/2023.02.09.527892v1.full (Full text)

Vascular Function, Systemic Inflammation, and Coagulation Activation 18 Months after COVID-19 Infection: An Observational Cohort Study

Abstract:

Introduction: Among its effect on virtually all other organs, COVID-19 affects the cardiovascular system, potentially jeopardizing the cardiovascular health of millions. Previous research has shown no indication of macrovascular dysfunction as reflected by carotid artery reactivity, but has shown sustained microvascular dysfunction, systemic inflammation, and coagulation activation at 3 months after acute COVID-19. The long-term effects of COVID-19 on vascular function remain unknown.
Materials and Methods: This cohort study involved 167 patients who participated in the COVAS trial. At 3 months and 18 months after acute COVID-19, macrovascular dysfunction was evaluated by measuring the carotid artery diameter in response to cold pressor testing. Additionally, plasma endothelin-1, von Willebrand factor, Interleukin(IL)-1ra, IL-6, IL-18, and coagulation factor complexes were measured using ELISA techniques.
Results: The prevalence of macrovascular dysfunction did not differ between 3 months (14.5%) and 18 months (11.7%) after COVID-19 infection (p = 0.585). However, there was a significant decrease in absolute carotid artery diameter change, 3.5% ± 4.7 vs. 2.7% ± 2.5, p—0.001, respectively. Additionally, levels of vWF:Ag were persistently high in 80% of COVID-19 survivors, reflecting endothelial cell damage and possibly attenuated endothelial function. Furthermore, while levels of the inflammatory cytokines interleukin(IL)-1RA and IL-18 were normalized and evidence of contact pathway activation was no longer present, the concentrations of IL-6 and thrombin:antithrombin complexes were further increased at 18 months versus 3 months (2.5 pg/mL ± 2.6 vs. 4.0 pg/mL ± 4.6, p = 0.006 and 4.9 μg/L ± 4.4 vs. 18.2 μg/L ± 11.4, p < 0.001, respectively).
Discussion: This study shows that 18 months after COVID-19 infection, the incidence of macrovascular dysfunction as defined by a constrictive response during carotid artery reactivity testing is not increased. Nonetheless, plasma biomarkers indicate sustained endothelial cell activation (vWF), systemic inflammation (IL-6), and extrinsic/common pathway coagulation activation (FVII:AT, TAT) 18 months after COVID-19 infection.
Source: Willems LH, Jacobs LMC, Groh LA, ten Cate H, Spronk HMH, Wilson-Storey B, Hannink G, van Kuijk SMJ, Ghossein-Doha C, Nagy M, Thijssen DHJ, van Petersen AS, Warlé MC. Vascular Function, Systemic Inflammation, and Coagulation Activation 18 Months after COVID-19 Infection: An Observational Cohort Study. Journal of Clinical Medicine. 2023; 12(4):1413. https://doi.org/10.3390/jcm12041413 https://www.mdpi.com/2077-0383/12/4/1413 (Full text)

The direct correlation between microbiota and SARS-CoV-2 infectious disease

Abstract:

The human microbiota is the good part of the human organism and is a collection of symbiotic microorganisms which aid in human physiological functions. Diseases that can be generated by an altered microbiota are continuously being studied, but it is quite evident how a damaged microbiota is involved in chronic inflammatory diseases, psychiatric diseases, and some bacterial or viral infections. However, the role of the microbiota in the host immune response to bacterial and viral infections is still not entirely understood.

Metabolites or components which are produced by the microbiota are useful in mediating microbiota-host interactions, thus influencing the host’s immune capacity. Recent evidence shows that the microbiota is evidently altered in patients with viral infections such as post-acute COVID-19 syndrome (PACS).

In this review, the associations between microbiota and COVID-19 infection are highlighted in terms of biological and clinical significance by emphasizing the mechanisms through which metabolites produced by the microbiota modulate immune responses to COVID-19 infection.

Source: Vitiello A, Ferrara F, Zovi A. The direct correlation between microbiota and SARS-CoV-2 infectious disease. Inflammopharmacology. 2023 Feb 1:1–8. doi: 10.1007/s10787-023-01145-9. Epub ahead of print. PMID: 36725821; PMCID: PMC9891758. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9891758/ (Full text)

Inflammatory and vascular biomarkers in post-COVID-19 syndrome: A systematic review and meta-analysis of over 20 biomarkers

Abstract:

Severe acute respiratory syndrome coronavirus 2 may inflict a post-viral condition known as post-COVID-19 syndrome (PCS) or long-COVID. Studies measuring levels of inflammatory and vascular biomarkers in blood, serum, or plasma of COVID-19 survivors with PCS versus non-PCS controls have produced mixed findings. Our review sought to meta-analyse those studies. A systematic literature search was performed across five databases until 25 June 2022, with an updated search on 1 November 2022.

Data analyses were performed with Review Manager and R Studio statistical software. Twenty-four biomarkers from 23 studies were meta-analysed. Higher levels of C-reactive protein (Standardized mean difference (SMD) = 0.20; 95% CI: 0.02-0.39), D-dimer (SMD = 0.27; 95% CI: 0.09-0.46), lactate dehydrogenase (SMD = 0.30; 95% CI: 0.05-0.54), and leukocytes (SMD = 0.34; 95% CI: 0.02-0.66) were found in COVID-19 survivors with PCS than in those without PCS. After sensitivity analyses, lymphocytes (SMD = 0.30; 95% CI: 0.12-0.48) and interleukin-6 (SMD = 0.30; 95% CI: 0.12-0.49) were also significantly higher in PCS than non-PCS cases. No significant differences were noted in the remaining biomarkers investigated (e.g., ferritin, platelets, troponin, and fibrinogen). Subgroup analyses suggested the biomarker changes were mainly driven by PCS cases diagnosed via manifestation of organ abnormalities rather than symptomatic persistence, as well as PCS cases with duration of <6 than ≥6 months.

In conclusion, our review pinpointed certain inflammatory and vascular biomarkers associated with PCS, which may shed light on potential new approaches to understanding, diagnosing, and treating PCS.

Source: Yong SJ, Halim A, Halim M, Liu S, Aljeldah M, Al Shammari BR, Alwarthan S, Alhajri M, Alawfi A, Alshengeti A, Khamis F, Alsalman J, Alshukairi AN, Abukhamis NA, Almaghrabi FS, Almuthree SA, Alsulaiman AM, Alshehail BM, Alfaraj AH, Alhawaj SA, Mohapatra RK, Rabaan AA. Inflammatory and vascular biomarkers in post-COVID-19 syndrome: A systematic review and meta-analysis of over 20 biomarkers. Rev Med Virol. 2023 Jan 27:e2424. doi: 10.1002/rmv.2424. Epub ahead of print. PMID: 36708022. https://pubmed.ncbi.nlm.nih.gov/36708022/ 

Long-COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): Potential neurophysiological biomarkers for these enigmatic entities

Since early in the pandemic, fatigue has been recognized as one of the most common persistent complaints in individuals infected with SARS-CoV-2, and constitutes one main symptom of the so-called long-COVID syndrome. The term fatigue refers to a sustained feeling of tiredness, which can be present at rest; it is not directly related to physical activity, but can be exacerbated disproportionally by exertion.

Survivors of other recent coronavirus outbreaks, such as severe acute respiratory syndrome (SARS) in 2002 and Middle East respiratory syndrome (MERS) in 2012 also developed chronic fatigue. These ‘post-infectious’ fatigue syndromes, including long-COVID, resemble myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a chronic disorder of unknown physiopathology characterized by fatigue, post-exertional malaise, chronic muscle or skeletal pain, and cognitive impairment (‘brain fog’).

Despite it being an extremely disabling symptom, the results of routine examinations are often normal in patients complaining of lingering fatigue, a phenomenon that has also led the medical-scientific community to view this condition with skepticism.

In physiology, fatigue is defined as a decrease in the maximal force-generating capacity of a muscle during exercise. It may result from peripheral processes distal to the neuromuscular junction and from central processes controlling the discharge rate of motoneurons.

Physical fatigue related to both central and peripheral nervous system dysfunction can be assessed with neurophysiological techniques including transcranial magnetic stimulation (TMS) of the motor cortex, electrical stimulation of nerve trunks or intramuscular nerve fibers, and electromyography (EMG) recordings.

In August 2021, the first study showing myopathic changes in quantitative EMG (qEMG) in long-COVID patients with musculoskeletal symptoms was published (). The same authors demonstrated myopathic qEMG features and histopathological changes in skeletal muscle biopsies in 16 patients with complaints of fatigue, myalgia, and/or weakness persisting for up to 14 months after mild to moderate COVID-19 (). The wide variety of histological changes in this study, including muscle fiber atrophy, mitochondrial changes, subsarcolemmal accumulation, inflammation, capillaries alteration, suggests that skeletal muscle may be a major target of SARS-CoV-2.

On the opposite side of the neuroaxis, dysfunction in the activity of the primary motor cortex and reduced corticomotor output may underlie fatigue.

The first TMS study on motor cortex physiology was conducted on 12 patients with long-term fatigue and ‘brain fog’ after severe COVID-19 (). It showed disruption of the physiological mechanism of post-contraction depression, i.e., the transient decrease in the amplitude of motor evoked potentials and prolongation of the cortical silent period after a fatiguing motor task, which depends on cortical inhibitory mechanisms and has the protective purpose of preventing muscle overload. Impairment of intracortical GABAergic activity, as indicated by disrupted long-interval intracortical inhibition, together with reduced excitability of the primary motor cortex was subsequently demonstrated in 67 patients with fatigue and cognitive difficulties after mild COVID-19 (). These patients also presented selective deficits in executive functions. Based on these findings, the authors proposed that fatigue depends on altered excitability and neurotransmission within the motor cortex at rest, and on abnormal reactivity to muscular exercise. In addition, reduced executive control may contribute to exacerbating poor physical performance and fatigue tolerance ().

These objective neurophysiological and histopathological findings showed for the first time that fatigue may due both to pathological processes in the muscle (the effector of the motor command) and/or at the site of motor command processing. The mechanisms of chronic dysfunction of neural and muscle cells may be sustained by inflammation or dysimmunity, triggered by SARS-COV-2 in predisposed individuals.

Immune-inflammatory and neuroendocrine mechanisms have also been implicated in ME/CFS. In particular, increased production of autoantibodies against CNS and autonomic nervous system targets, such as the ß2 adrenergic receptor (ß2AdR), have been documented (). As ß2AdR are important vasodilators, their functional disturbance may result in vasoconstriction and hypoxemia with chronic muscular and cerebral hypoperfusion.

The COVID-19 pandemic is likely to greatly increase the incidence of ME/CFS, so that the intense research on the pathophysiological mechanisms of fatigue in long-COVID can help to shed light on a poorly understood and underestimated syndrome.

Source: Versace V, Tankisi H. Long-COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): Potential neurophysiological biomarkers for these enigmatic entities. Clin Neurophysiol. 2023 Jan 13;147:58-59. doi: 10.1016/j.clinph.2023.01.001. Epub ahead of print. PMID: 36657309; PMCID: PMC9838078. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9838078/ (Full text)

Can Baseline IL-6 Levels Predict Long COVID in Subjects Hospitalized for SARS-CoV-2 Disease?

Abstract:

The immune response to infection plays a crucial role in the pathogenesis of COVID-19, but several patients develop a wide range of persistent symptoms, which is becoming a major global health and economic burden. However, reliable indicators are not yet available to predict the persistence of symptoms typical of the so-called long COVID. Our study aims to explore an eventual role of IL-6 levels as a marker of long COVID. Altogether, 184 patients admitted to the COVID Medicine Unit of the University Hospital in Palermo, Italy, from the 1st of September 2020, were analyzed.

Patients were divided into two groups according to the IL-6 serum levels (normal or elevated), considering the serum IL-6 levels measured during the first four days of hospitalization. In our study, higher serum IL-6 levels were associated with a doubled higher risk of long COVID (OR = 2.05; 95% CI: 1.04-4.50) and, in particular, they were associated with a higher incidence of mobility decline (OR = 2.55; 95% CI: 1.08-9.40) and PTSD (OR = 2.38; 95% CI: 1.06-8.61). The analysis of our case series confirmed the prominent role of IL-6 levels in response to SARS-CoV-2 infection, as predictors not only of COVID-19 disease severity and unfavorable outcomes, but also long COVID development trends.

Source: Giannitrapani L, Mirarchi L, Amodeo S, Licata A, Soresi M, Cavaleri F, Casalicchio S, Ciulla G, Ciuppa ME, Cervello M, Barbagallo M, Veronese N, The Comepa Group. Can Baseline IL-6 Levels Predict Long COVID in Subjects Hospitalized for SARS-CoV-2 Disease? Int J Mol Sci. 2023 Jan 15;24(2):1731. doi: 10.3390/ijms24021731. PMID: 36675242. https://www.mdpi.com/1422-0067/24/2/1731 (Full text)

Long COVID: Is There a Role for Antidepressants?

Abstract:

Two years into this historic pandemic, the scientific and healthcare communities continue to learn a great deal regarding COVID-19. The most urgent and immediate focus has been on vaccine development for disease prevention/mitigation and on identification of effective therapeutic interventions for acute phase of illness. However, attention is increasingly being placed on formulating treatment strategies for individuals who are post-COVID-19 and experiencing a syndrome of persistent symptoms that is being referred to as long COVID.

One strategy is to repurpose drugs which have been approved for other conditions and subsequently assess their safety and efficacy when applied to COVID-19. In this light, antidepressant medications have garnered attention amidst evidence supporting anti-inflammatory and anti-viral properties.

In this article, we present purported anti-inflammatory mechanisms of antidepressants, review studies appearing in the literature to date regarding antidepressants and acute COVID-19, and discuss the utility of antidepressants as a potential therapeutic resource for long COVID.

Source: Rivas-Vázquez R, Carrazana EJ, Blais MA, Rey GJ, RivasVázquez E, Quintana AA. Long COVID: Is There a Role for Antidepressants? Neurol Curr Res. 2022;2(3):1019. https://www.medtextpublications.com/open-access/long-covid-is-there-a-role-for-antidepressants-1249.pdf (Full text)

Novel clinical and immunological features associated with persistent post-acute sequelae of COVID-19 after six months of follow-up: a pilot study

Abstract:

Background: Currently, there is scant information regarding the features associated to the persistence of post-COVID-19 syndrome, which is the main aim of the present study.

Methods: A cohort study of 102 COVID-19 patients was conducted. The post-COVID-19 symptoms were assessed by a standardised questionnaire. Lymphocyte immunophenotyping was performed by flow cytometry and chemokines/cytokines, neutrophil extracellular traps, the tripartite motif 63, anti-cellular, and anti-SARS-CoV-2 IgG antibodies were addressed in serum. The primary outcome was the persistence of post-COVID-19 syndrome after six months follow-up.

Results: Thirteen patients (12.7%) developed the primary outcome and had a more frequent history of post-COVID-19 syndrome 3 months after infection onset (p = .044), increased levels of IL-1α (p = .011) and IP-10 (p = .037) and increased CD57 expression in CD8+ T cells (p = .003). There was a trend towards higher levels of IFN-γ (p = .051), IL-1β (p = .062) and IL-6 (p = .087). The history of post COVID-19 in the previous 3 months, obesity, baseline serum MIP-1α and IP-10, and CD57 expression in CD8+ T cells were independently associated with the persistence of post-COVID-19 syndrome.

Conclusion: Our data suggest an important relationship between a pro-inflammatory state mediated through metabolic pathways related to obesity and increased cellular senescence as a key element in the persistence of post-COVID-19 syndrome at six months of follow-up.

Source: Torres-Ruiz J, Lomelín-Gascón J, Lira Luna J, Vargas-Castro AS, Pérez-Fragoso A, Nuñez-Aguirre M, Alcalá-Carmona B, Absalón-Aguilar A, Balderas-Miranda JT, Maravillas-Montero JL, Mejía-Domínguez NR, Núñez-Álvarez C, Llorente L, Romero-Ramírez S, Sosa-Hernández VA, Cervantes-Díaz R, Juárez-Vega G, Meza-Sánchez D, Rull-Gabayet M, Martínez-Juárez LA, Morales L, López-López LN, Negrete-Trujillo JA, Falcón-Lezama JA, Valdez-Vázquez RR, Gallardo-Rincón H, Tapia-Conyer R, Gómez-Martín D. Novel clinical and immunological features associated with persistent post-acute sequelae of COVID-19 after six months of follow-up: a pilot study. Infect Dis (Lond). 2023 Jan 13:1-12. doi: 10.1080/23744235.2022.2158217. Epub ahead of print. PMID: 36637466. https://www.tandfonline.com/doi/full/10.1080/23744235.2022.2158217 (Full text)

SARS-CoV-2 escape from cytotoxic T cells during long-term COVID-19

Abstract:

Evolution of SARS-CoV-2 in immunocompromised hosts may result in novel variants with changed properties. While escape from humoral immunity certainly contributes to intra-host evolution, escape from cellular immunity is poorly understood. Here, we report a case of long-term COVID-19 in an immunocompromised patient with non-Hodgkin’s lymphoma who received treatment with rituximab and lacked neutralizing antibodies.

Over the 318 days of the disease, the SARS-CoV-2 genome gained a total of 40 changes, 34 of which were present by the end of the study period. Among the acquired mutations, 12 reduced or prevented the binding of known immunogenic SARS-CoV-2 HLA class I antigens. By experimentally assessing the effect of a subset of the escape mutations, we show that they resulted in a loss of as much as ~1% of effector CD8 T cell response. Our results indicate that CD8 T cell escape represents a major underappreciated contributor to SARS-CoV-2 evolution in humans.

Source: Stanevich OV, Alekseeva EI, Sergeeva M, Fadeev AV, Komissarova KS, Ivanova AA, Simakova TS, Vasilyev KA, Shurygina AP, Stukova MA, Safina KR, Nabieva ER, Garushyants SK, Klink GV, Bakin EA, Zabutova JV, Kholodnaia AN, Lukina OV, Skorokhod IA, Ryabchikova VV, Medvedeva NV, Lioznov DA, Danilenko DM, Chudakov DM, Komissarov AB, Bazykin GA. SARS-CoV-2 escape from cytotoxic T cells during long-term COVID-19. Nat Commun. 2023 Jan 10;14(1):149. doi: 10.1038/s41467-022-34033-x. PMID: 36627290; PMCID: PMC9831376. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9831376/ (Full text)