Sex differences in symptomatology and immune profiles of Long COVID

Abstract:

Strong sex differences in the frequencies and manifestations of Long COVID (LC) have been reported with females significantly more likely than males to present with LC after acute SARS-CoV-2 infection1-7. However, whether immunological traits underlying LC differ between sexes, and whether such differences explain the differential manifestations of LC symptomology is currently unknown.

Here, we performed sex-based multi-dimensional immune-endocrine profiling of 165 individuals8 with and without LC in an exploratory, cross-sectional study to identify key immunological traits underlying biological sex differences in LC.

We found that female and male participants with LC experienced different sets of symptoms, and distinct patterns of organ system involvement, with female participants suffering from a higher symptom burden. Machine learning approaches identified differential sets of immune features that characterized LC in females and males. Males with LC had decreased frequencies of monocyte and DC populations, elevated NK cells, and plasma cytokines including IL-8 and TGF-β-family members.

Females with LC had increased frequencies of exhausted T cells, cytokine-secreting T cells, higher antibody reactivity to latent herpes viruses including EBV, HSV-2, and CMV, and lower testosterone levels than their control female counterparts. Testosterone levels were significantly associated with lower symptom burden in LC participants over sex designation.

These findings suggest distinct immunological processes of LC in females and males and illuminate the crucial role of immune-endocrine dysregulation in sex-specific pathology.

Source: Julio Silva, Takehiro Takahashi, Jamie Wood, Peiwen Lu, Sasha Tabachnikova, Jeffrey Gehlhausen, Kerrie Greene, Bornali Bhattacharjee, Valter Silva Monteiro, Carolina Lucas, Rahul Dhodapkar, Laura Tabacof, Mario Pena-Hernandez, Kathy Kamath, Tianyang Mao, Dayna Mccarthy, Ruslan Medzhitov, David van Dijk, Harlan Krumholz, Leying Guan, David Putrino, Akiko Iwasaki. Sex differences in symptomatology and immune profiles of Long COVID. medRxiv 2024.02.29.24303568; doi: https://doi.org/10.1101/2024.02.29.24303568 https://www.medrxiv.org/content/10.1101/2024.02.29.24303568v1 (Full study available as PDF file)

Herpesvirus Infection as a Systemic Pathological Axis in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Understanding the pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is critical for advancing treatment options. This review explores the novel hypothesis that herpesviruses’ infection of endothelial cells (ECs) may underlie ME/CFS symptomatology.
We review evidence linking herpesviruses to persistent EC infection and the implications for endothelial dysfunction, encompassing blood flow regulation, coagulation, and cognitive impairment – symptoms consistent with ME/CFS and Long COVID. The paper provides a synthesis of current research on herpesvirus latency and reactivation, detailing the impact on ECs and subsequent systemic complications, including latent modulation and long-term maladaptation.
We suggest that the chronicity of ME/CFS symptoms and the multisystemic nature of the disease may be partly attributable to herpesvirus-induced endothelial maladaptation. Our conclusions underscore the necessity for further investigation into the prevalence and load of herpesvirus infection within ECs of ME/CFS patients.
This review offers a conceptual advance by proposing an endothelial infection model as a systemic mechanism contributing to ME/CFS, steering future research towards potentially unexplored avenues in understanding and treating this complex syndrome.
Source: Nunes, J.M.; Kell, D.B.; Pretorius, E. Herpesvirus Infection as a Systemic Pathological Axis in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Preprints 2024, 2024011486. https://doi.org/10.20944/preprints202401.1486.v1 https://www.preprints.org/manuscript/202401.1486/v1 (Full text available as PDF file)

Persistent complement dysregulation with signs of thromboinflammation in active Long Covid

Abstract:

Long Covid is a debilitating condition of unknown etiology. We performed multimodal proteomics analyses of blood serum from COVID-19 patients followed up to 12 months after confirmed severe acute respiratory syndrome coronavirus 2 infection. Analysis of >6500 proteins in 268 longitudinal samples revealed dysregulated activation of the complement system, an innate immune protection and homeostasis mechanism, in individuals experiencing Long Covid.

Thus, active Long Covid was characterized by terminal complement system dysregulation and ongoing activation of the alternative and classical complement pathways, the latter associated with increased antibody titers against several herpesviruses possibly stimulating this pathway. Moreover, markers of hemolysis, tissue injury, platelet activation, and monocyte–platelet aggregates were increased in Long Covid. Machine learning confirmed complement and thromboinflammatory proteins as top biomarkers, warranting diagnostic and therapeutic interrogation of these systems.

Source: Carlo Cervia-Hasler et al. Persistent complement dysregulation with signs of thromboinflammation in active Long Covid. Science383,eadg7942(2024). DOI: 10.1126/science.adg7942 https://www.science.org/doi/10.1126/science.adg7942 (Full text)

Heterogenous circulating miRNA changes in ME/CFS converge on a unified cluster of target genes: A computational analysis

Abstract:

Myalgic Encephalomyelitis / Chronic Fatigue Syndrome is a debilitating, multisystem disease of unknown mechanism, with a currently ongoing search for its endocrine mediators. Circulating microRNAs (miRNA) are a promising candidate for such a mediator and have been reported as significantly different in the patient population versus healthy controls by multiple studies. None of these studies, however, agree with each other on which specific miRNA are under- or over-expressed.

This discrepancy is the subject of the computational study presented here, in which a deep dive into the predicted gene targets and their functional interactions is conducted, revealing that the aberrant circulating miRNAs in ME/CFS, although different between patients, seem to mainly target the same specific set of genes (p ≈ 0.0018), which are very functionally related to each other (p ≲ 0.0001).

Further analysis of these functional relations, based on directional pathway information, points to impairments in exercise hyperemia, angiogenic adaptations to hypoxia, antioxidant defenses, and TGF-β signaling, as well as a shift towards mitochondrial fission, corroborating and explaining previous direct observations in ME/CFS. Many transcription factors and epigenetic modulators are implicated as well, with currently uncertain downstream combinatory effects.

As the results show significant similarity to previous research on latent herpesvirus involvement in ME/CFS, the possibility of a herpesvirus origin of these miRNA changes is also explored through further computational analysis and literature review, showing that 8 out of the 10 most central miRNAs analyzed are known to be upregulated by various herpesviruses. In total, the results establish an appreciable and possibly central role for circulating microRNAs in ME/CFS etiology that merits further experimental research.

Source: Kaczmarek MP. Heterogenous circulating miRNA changes in ME/CFS converge on a unified cluster of target genes: A computational analysis. PLoS One. 2023 Dec 29;18(12):e0296060. doi: 10.1371/journal.pone.0296060. PMID: 38157384; PMCID: PMC10756525. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10756525/ (Full text)

Effect of monovalent COVID-19 vaccines on viral interference between SARS-CoV-2 and several DNA viruses in patients with long-COVID syndrome

Abstract:

Epstein-Barr virus (EBV) reactivation may be involved in long-COVID symptoms, but reactivation of other viruses as a factor has received less attention. Here we evaluated the reactivation of parvovirus-B19 and several members of the Herpesviridae family (DNA viruses) in patients with long-COVID syndrome. We hypothesized that monovalent COVID-19 vaccines inhibit viral interference between SARS-CoV-2 and several DNA viruses in patients with long-COVID syndrome, thereby reducing clinical symptoms.

Clinical and laboratory data for 252 consecutive patients with PCR-verified past SARS-CoV-2 infection and long-COVID syndrome (155 vaccinated and 97 non-vaccinated) were recorded during April 2021-May 2022 (median 243 days post-COVID-19 infection). DNA virus-related IgG and IgM titers were compared between vaccinated and non-vaccinated long-COVID patients and with age- and sex-matched non-infected, unvaccinated (pan-negative for spike-antibody) controls.

Vaccination with monovalent COVID-19 vaccines was associated with significantly less frequent fatigue and multiorgan symptoms (p < 0.001), significantly less cumulative DNA virus-related IgM positivity, significantly lower levels of plasma IgG subfractions 2 and 4, and significantly lower quantitative cytomegalovirus IgG and IgM and EBV IgM titers. These results indicate that anti-SARS-CoV-2 vaccination may interrupt viral cross-talk in patients with long-COVID syndrome (ClinicalTrials.gov Identifier: NCT05398952).

Source: Gyöngyösi M, Lukovic D, Mester-Tonczar J, Zlabinger K, Einzinger P, Spannbauer A, Schweiger V, Schefberger K, Samaha E, Bergler-Klein J, Riesenhuber M, Nitsche C, Hengstenberg C, Mucher P, Haslacher H, Breuer M, Strassl R, Puchhammer-Stöckl E, Loewe C, Beitzke D, Hasimbegovic E, Zelniker TA. Effect of monovalent COVID-19 vaccines on viral interference between SARS-CoV-2 and several DNA viruses in patients with long-COVID syndrome. NPJ Vaccines. 2023 Sep 29;8(1):145. doi: 10.1038/s41541-023-00739-2. PMID: 37773184; PMCID: PMC10541897. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10541897/ (Full text)

Association analysis between symptomology and herpesvirus IgG antibody concentrations in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and multiple sclerosis

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and multiple sclerosis (MS) are two complex and multifactorial diseases whose patients experience persistent fatigue, cognitive impairment, among other shared symptoms. The onset of these diseases has also been linked to acute herpesvirus infections or their reactivations.

In this work, we re-analyzed a previously-described dataset related to IgG antibody responses to 6 herpesviruses (CMV – cytomegalovirus; EBV – Epstein-Barr virus; HHV6 – human herpesvirus-6; HSV1 and HSV2 – herpes simplex virus-1 and -2; VZV – varicella-zoster virus) from the United Kingdom ME/CFS biobank. The primary goal was to report the underlying symptomology and its association with herpesvirus IgG antibodies using data from 4 disease-trigger-based subgroups of ME/CFS patients (n = 222) and patients with MS (n = 46). A secondary objective was to assess whether serological data could distinguish ME/CFS and its subgroup from MS using a SuperLearner (SL) algorithm.

There was evidence for a significant negative association between temporary eye insight disturbance and CMV antibody concentrations and for a significant positive association between bladder problems and EBV antibody concentrations in the MS group.

In the ME/CFS or its subgroups, the most significant antibody-symptom association was obtained for increasing HSV1 antibody concentration and brain fog, a finding in line with a negative impact of HSV1 exposure on cognitive outcomes in both healthy and disease conditions. There was also evidence for a higher number of significant antibody-symptom associations in the MS group than in the ME/CFS group.

When we combined all the serological data in an SL algorithm, we could distinguish three ME/CFS subgroups (unknown disease trigger, non-infection trigger, and an infection disease trigger confirmed in the lab at the time of the event) from the MS group. However, we could not find the same for the remaining ME/CFS group (related to an unconfirmed infection disease).

In conclusion, IgG antibody data explains more the symptomology of MS patients than the one of ME/CFS patients. Given the fluctuating nature of symptoms in ME/CFS patients, the clinical implication of these findings remains to be determined with a longitudinal study. This study is likely to ascertain the robustness of the associations during natural disease course.

Source: Tiago Dias Domingues, João Malato, Anna D. Grabowska, Ji-Sook Lee, Jose Ameijeiras-Alonso, Przemyslaw Biecek, Luís Graça, Helena Mouriño, Carmen Scheibenbogen, Francisco Westermeier, Luis Nacul, Jacqueline M. Cliff, Eliana Lacerda, Nuno Sepúlveda,
Association analysis between symptomology and herpesvirus IgG antibody concentrations in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and multiple sclerosis. Heliyon, https://doi.org/10.1016/j.heliyon.2023.e18250 https://www.sciencedirect.com/science/article/pii/S2405844023054580 (Full text)

Increased circulating fibronectin, depletion of natural IgM and heightened EBV, HSV-1 reactivation in ME/CFS and long COVID

Abstract:

Myalgic Encephalomyelitis/ Chronic Fatigue syndrome (ME/CFS) is a complex, debilitating, long-term illness without a diagnostic biomarker. ME/CFS patients share overlapping symptoms with long COVID patients, an observation which has strengthened the infectious origin hypothesis of ME/CFS. However, the exact sequence of events leading to disease development is largely unknown for both clinical conditions.

Here we show antibody response to herpesvirus dUTPases, particularly to that of Epstein-Barr virus (EBV) and HSV-1, increased circulating fibronectin (FN1) levels in serum and depletion of natural IgM against fibronectin ((n)IgM-FN1) are common factors for both severe ME/CFS and long COVID. We provide evidence for herpesvirus dUTPases-mediated alterations in host cell cytoskeleton, mitochondrial dysfunction and OXPHOS.

Our data show altered active immune complexes, immunoglobulin-mediated mitochondrial fragmentation as well as adaptive IgM production in ME/CFS patients. Our findings provide mechanistic insight into both ME/CFS and long COVID development. Finding of increased circulating FN1 and depletion of (n)IgM-FN1 as a biomarker for the severity of both ME/CFS and long COVID has an immediate implication in diagnostics and development of treatment modalities.

Source: Zheng Liu, Claudia Hollmann, Sharada Kalanidhi, Arnhild Grothey, Samuel Keating, Irene Mena-Palomo, Stephanie Lamer, Andreas Schlosser, Agnes Kaiping, Carsten Scheller, Franziska Sotzny, Anna Horn, Carolin Nuernberger, Vladimir Cejka, Boshra Afshar, Thomas Bahmer, Stefan Schreiber, Joerg Janne Vehreschild, Olga Milljukov, Christian Schaefer, Luzie Kretzler, Thomas Keil, Jens-Peter Reese, Felizitas A Eichner, Lena Schmidbauer, Peter U Heuschmann, Stefan Stoerk, Caroline Morbach, Gabriela Riemekasten, Niklas Beyersdorf, Carmen Scheibenbogen, Robert K Naviaux, Marshall Williams, Maria E Ariza, Bhupesh Kumar Prusty. Increased circulating fibronectin, depletion of natural IgM and heightened EBV, HSV-1 reactivation in ME/CFS and long COVID. medRxiv 2023.06.23.23291827; doi: https://doi.org/10.1101/2023.06.23.23291827 https://www.medrxiv.org/content/10.1101/2023.06.23.23291827v1 (Full text available as PDF file)

Sex-Dependent Transcriptional Changes in Response to Stress in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Project

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, multi-symptom illness characterized by debilitating fatigue and post-exertional malaise (PEM). Numerous studies have reported sex differences at the epidemiological, cellular, and molecular levels between male and female ME/CFS patients. To gain further insight into these sex-dependent changes, we evaluated differential gene expression by RNA-sequencing (RNA-Seq) in 33 ME/CFS patients (20 female, 13 male) and 34 matched healthy controls (20 female and 14 male) before, during, and after an exercise challenge intended to provoke PEM.
Our findings revealed that pathways related to immune-cell signaling (including IL-12) and natural killer cell cytotoxicity were activated as a result of exertion in the male ME/CFS cohort, while female ME/CFS patients did not show significant enough changes in gene expression to meet the criteria for the differential expression. Functional analysis during recovery from an exercise challenge showed that male ME/CFS patients had distinct changes in the regulation of specific cytokine signals (including IL-1β). Meanwhile, female ME/CFS patients had significant alterations in gene networks related to cell stress, response to herpes viruses, and NF-κβ signaling. The functional pathways and differentially expressed genes highlighted in this pilot project provide insight into the sex-specific pathophysiology of ME/CFS.
Source: Gamer J, Van Booven DJ, Zarnowski O, Arango S, Elias M, Kurian A, Joseph A, Perez M, Collado F, Klimas N, et al. Sex-Dependent Transcriptional Changes in Response to Stress in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Project. International Journal of Molecular Sciences. 2023; 24(12):10255. https://doi.org/10.3390/ijms241210255 https://www.mdpi.com/1422-0067/24/12/10255 (Full text)

Systematic review with meta-analysis of active herpesvirus infections in patients with COVID-19: Old players on the new field

Abstract:

Objectives: Herpesviruses are ubiquitous and after primary infection they establish lifelong latency. The impairment of maintaining latency with short-term or long-term consequences could be triggered by other infection. Therefore, reactivation of herpesviruses in COVID-19 patients represents an emerging issue.

Design and methods: This study provided the first systematic review with meta-analysis of studies that evaluated active human herpesvirus (HHV) infection (defined as the presence of IgM antibodies or HHV-DNA) in COVID-19 patients and included 36 publications collected by searching through PubMed, SCOPUS, and Web of science until November 2022.

Results: The prevalence of active EBV, HHV6, HSV, CMV, HSV1, and VZV infection in COVID-19 population was 41% (95% CI =27%-57%),3% (95% CI=17%-54%),28% (95% CI=1%-85%),25% (95% CI=1%-63%),22% (95% CI=10%-35%),and 18% (95% CI=4%-34%),respectively. There was a 6 times higher chance for active EBV infection in patients with severe COVID-19 than in non-COVID-19 controls (OR=6.45, 95% CI=1.09-38.13, p=0.040), although there was no difference in the prevalence of all evaluated active herpesvirus infections between COVID-19 patients and non-COVID-19 controls.

Conclusions: Future research of herpesvirus and SARS-CoV-2 coinfections must be prioritized to define: who, when and how to be tested, as well as how to effectively treat HHVs reactivations in acute and long COVID-19 patients.

Source: Banko A, Miljanovic D, Cirkovic A. Systematic review with meta-analysis of active herpesvirus infections in patients with COVID-19: Old players on the new field. Int J Infect Dis. 2023 Jan 31:S1201-9712(23)00037-1. doi: 10.1016/j.ijid.2023.01.036. Epub ahead of print. PMID: 36736577; PMCID: PMC9889115. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9889115/ (Full text)

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Human Herpesviruses Are Back!

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) or Systemic Exertion Intolerance Disease (SEID) is a chronic multisystem illness of unconfirmed etiology. There are currently no biomarkers and/or signatures available to assist in the diagnosis of the syndrome and while numerous mechanisms have been hypothesized to explain the pathology of ME/CFS, the triggers and/or drivers remain unknown.

Initial studies suggested a potential role of the human herpesviruses especially Epstein-Barr virus (EBV) in the disease process but inconsistent and conflicting data led to the erroneous suggestion that these viruses had no role in the syndrome. New studies using more advanced approaches have now demonstrated that specific proteins encoded by EBV could contribute to the immune and neurological abnormalities exhibited by a subgroup of patients with ME/CFS. Elucidating the role of these herpesvirus proteins in ME/CFS may lead to the identification of specific biomarkers and the development of novel therapeutics.

Source: Ariza ME. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Human Herpesviruses Are Back! Biomolecules. 2021 Jan 29;11(2):185. doi: 10.3390/biom11020185. PMID: 33572802; PMCID: PMC7912523. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7912523/ (Full text)