Epitope-anchored contrastive transfer learning for paired CD8+ T cell receptor-antigen recognition (preprint)

Understanding the mechanisms of T-cell antigen recognition that underpin adaptive immune responses is critical for the development of vaccines, immunotherapies, and treatments against autoimmune diseases. Despite extensive research efforts, the accurate identification of T cell receptor (TCR)-antigen binding pairs remains a significant challenge due to the vast diversity and cross-reactivity of TCRs. Here, we propose a deep-learning framework termed Epitope-anchored Contrastive Transfer Learning (EPACT) tailored to paired human CD8+ TCRs from single-cell sequencing data. Harnessing the pre-trained representations and the contrastive co-embedding space, EPACT demonstrates state-of-the-art model generalizability in predicting TCR binding specificity for unseen epitopes and distinct TCR repertoires, offering potential values for practical outcomes in real-world scenarios. The contrastive learning paradigm achieves highly precise predictions for immunodominant epitopes and facilitates interpretable analysis of epitope-specific T cells. The TCR binding strength predicted by EPACT aligns well with the surge in spike-specific immune responses targeting SARS-CoV-2 epitopes after vaccination. We further fine-tune EPACT on TCR-epitope structural data to decipher the residue-level interactions involved in T-cell antigen recognition. EPACT not only exhibits superior capabilities in quantifying inter-chain distance matrices and identifying contact residue pairs but also corroborates the presence of molecular mimicry across multiple tumor-associated antigens. Together, EPACT can serve as a useful AI approach with significant potential in practical applications and contribute toward the development of TCR-based diagnostics and immunotherapies.

Genome-wide association study reveals different T cell distributions in peripheral blood of healthy individuals at high genetic risk of type 1 diabetes and long COVID (preprint)

The immune system plays a crucial role in many human diseases. In this context, genome-wide association studies (GWAS) offer valuable insights to elucidate the role of immunity in health and disease. The present multi-omics study aimed to identify genetic determinants of immune cell type distributions in the blood of healthy individuals and to assess whether the distributions of these cells may play a role for autoimmune and COVID-19 disease risk. To this end, the frequencies of different immune cells in 483 healthy individuals from the Berlin Aging Study II were quantified using flow cytometry, and GWAS was performed for 92 immune cell phenotypes. Additionally, we performed linear regression analyses of immune cell distributions using polygenic risk scores (PRS) based on prior GWAS for five autoimmune diseases as well as for COVID-19 infection and post-COVID syndrome ("long COVID"). We validated seven previously described immune loci and identified 13 novel loci showing genome-wide significant (=5.00E-8) association with different immune cell phenotypes. The most significant novel signal was conferred by the SLC52A3 locus, encoding for a riboflavin transporter protein, which was associated with naïve CD57+ CD8+ T cells (p=4.13E-17) and colocalized with SLC52A3 expression. Several novel loci contained immunologically plausible candidate genes, e.g., variants near TBATA and B3GAT1 representing genes associated with T cell phenotypes. The PRS of type 1 diabetes were significantly associated with CD8+ T cells at different differentiation states (p[≤]7.02E-4), and PRS of long COVID were associated with early-differentiated CD4+ T cells (p[≤]1.54E-4). In conclusion, our extensive immune cell GWAS analyses highlight several novel genetic loci of likely relevance for immune system function. Furthermore, our PRS analyses point to a shared genetic basis between immune cell distributions in healthy adults and T1D (CD8+ T cells) as well as long COVID (CD4+ T cells).

Deciphering Abnormal Platelet Subpopulations in Inflammatory Diseases through Machine Learning and Single-Cell Transcriptomics (preprint)

IntroductionThe transcriptional heterogeneity of activated platelets, play a significant role in contributing to negative outcomes in sepsis, COVID-19, and autoimmune diseases such as systemic lupus erythematosus (SLE). Despite this, our understanding of these heterogeneous platelet responses remains limited. In this study, we aim to investigate the diverse transcriptional profiles of activated platelets in these diseases, with the goal of deciphering this platelet heterogeneity for new therapeutic strategies to target abnormal and pathogenic platelet subtypes. Materials and methodsWe obtained the single cell transcriptional profiles of blood platelets from patients with COVID-19, sepsis, and SLE. Utilizing machine learning algorithms, Deep Neural Network (DNN) and eXtreme Gradient Boosting (XGB), we discerned the distinct transcriptomic signatures indicative of fatal versus survival clinical outcomes. Our methodological framework incorporated source data annotations and platelet markers and used SingleR and Seurat for detailed profiling. Additionally, we implemented Uniform Manifold Approximation and Projection (UMAP) for dimensionality reduction and visualization, aiding in the detection of various platelet subtypes and their correlation with disease status and patient outcomes. ResultsOur study identified distinct platelet subpopulations that are associated with disease severity. We demonstrated that alterations in platelet transcription patterns can exacerbate endotheliopathy, potentially heightening the risk of coagulation in fatal patients. Moreover, these changes can also influence lymphocyte function, indicating a more extensive role for platelets in inflammatory and immune responses. ConclusionsEnhanced transcriptional heterogeneity in activated platelets is linked to adverse outcomes in conditions such as sepsis, COVID-19, and autoimmune diseases. The discovery of these unique platelet subpopulations paves the way for innovative therapeutic strategies targeting platelet activation, which could potentially improve patient outcomes. Summary sentenceSingle-Cell RNA Sequencing Analysis of Platelets from COVID-19, Sepsis, and SLE Reveals Disease Signatures and Treatment Options to Prevent Patient Mortality. Graphical AbstractsO_LIThe platelet to T cell ratio proportion in PBMC was identified as the most potent predictor for distinguishing survivors from fatal patients, underscores the potential of this ratio as a prognostic biomarker. C_LIO_LIThe discovery of different platelet subgroups, especially active coagulation, hypoxic, and quiescent clusters, in fatal COVID-19 patients, indicates potential targeted treatment strategies. C_LIO_LIIn patients with severe and fatal conditions, we observed three key phenomena: the aggregation of platelets with monocytes, the amplification of endothelial dysfunction by platelets, and a decrease in lymphocyte activation and differentiation due to platelets. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=197 SRC="FIGDIR/small/572680v1_ufig1.gif" ALT="Figure 1"> View larger version (64K): org.highwire.dtl.DTLVardef@141ca55org.highwire.dtl.DTLVardef@4ad1aborg.highwire.dtl.DTLVardef@b400forg.highwire.dtl.DTLVardef@9ad44e_HPS_FORMAT_FIGEXP M_FIG C_FIG

Deep profiling of antigen-specific B cells from different pathogens identifies novel compartments in the IgG memory B cell and antibody-secreting cell lineages (preprint)

A better understanding of the bifurcation of human B cell differentiation into memory B cells (MBC) and antibody-secreting cells (ASC) and identification of MBC and ASC precursors is crucial to optimize vaccination strategies or block undesired antibody responses. To unravel the dynamics of antigen-induced B cell responses, we compared circulating B cells reactive to SARS-CoV-2 (Spike, RBD and Nucleocapsid) in COVID-19 convalescent individuals to B cells specific to Influenza-HA, RSV-F and TT, induced much longer ago. High-dimensional spectral flow cytometry indicated that the decision point between ASC- and MBC-formation lies in the CD43+CD71+IgG+ Activated B cell compartment, showing properties indicative of recent germinal center activity and recent antigen encounter. Within this Activated B cells compartment, CD86+ B cells exhibited close phenotypical similarity with ASC, while CD86- B cells were closely related to IgG+ MBCs. Additionally, different activation stages of the IgG+ MBC compartment could be further elucidated. The expression of CD73 and CD24, regulators of survival and cellular metabolic quiescence, discerned activated MBCs from resting MBCs. Activated MBCs (CD73-CD24lo) exhibited phenotypical similarities with CD86- IgG+ Activated B cells and were restricted to SARS-CoV-2 specificities, contrasting with the resting MBC compartment (CD73-/CD24hi) that exclusively encompassed antigen-specific B cells established long ago. Overall, these findings identify novel stages for IgG+ MBC and ASC formation and bring us closer in defining the decision point for MBC or ASC differentiation. ImportanceIn this study, researchers aimed to better understand human B cell differentiation and their role in establishing long-lived humoral immunity. Using high-dimensional flow cytometry, they studied B cells reactive to three SARS-CoV-2 antigens in individuals convalescent for COVID-19, and compared their phenotypes to B cells reactive to three distinct protein antigens derived from vaccines or viruses encountered months to decades before. Their findings showed that Activated B cells reflect recent germinal center graduates that may have diverse fates; with some feeding the pool of antibody-secreting cells and others fueling the resting memory B cell compartment. Activated B cells gradually differentiate into resting memory B cells through an activated MBC phase. Increased expression of the cellular metabolic regulators CD73 and CD24 in resting memory B cells distinguishes them from the activated memory B cells phase, and is likely involved in sustaining a durable memory of humoral immunity. These findings are crucial for the development of vaccines that provide lifelong protection and may show potential to define reactive B cells in diseases where the cognate-antigen is still unknown such as in autoimmunity, cancers, or novel viral outbreaks.

Xenosialylation: Role in SARS/CoV-2 Post-infectious and Post-vaccination Complications and Common Cause of Hyperimmune/Autoimmune Diseases (preprint)

The host glycosylation mechanism synthesizes the carbohydrates of glycoproteins of viral envelopes. Due to the loss of the Cytidine Monophospho-N-Acetylneuraminic Acid Hydroxylase gene by some mammalian species, including humans (negative-CMAH), Neu5Gc is no longer synthesized. Uptake of Neu5Gc by negative-CMAH species, through the intake of food products derived from positive-CMAH mammals, leads to incorporating Neu5Gc-glycans in the glycocalyx (xenosialylation). Neu5Gc, being a Mammalian-associated Carbohydrate Antigen (MCA), acts as a non-self-antigen, inducing an inflammatory reaction (Xenosialitis), and triggering the production of circulating antiNeu5Gc antibodies to attack/remove all incorporated Neu5Gc. In the state of Xenosialitis, the virus-neutralizing antibodies produced by a heavily xenosialylated patient following exposure to viral infection (including SarsCoV2) or anti SarsCoV2 vaccination cross-react against all incorporated non-self Neu5Gc-MCA glycans due to their resemblance with viral envelope antigens synthesized by the host glycosylation mechanism. In addition, the circulating anti-XeSias antibodies determine the massive removal of the circulating neutralizing FC-xeno-contaminated antibodies by the serum, living only the hyper-inflammatory agalattosylated antiviral IgG antibodies. Therefore, we hypothesize that the combination of antibody cross-reaction against non-self Neu5Gc-MCA glycans and the massive removal of the xeno-contaminated newly formed neutralizing antibodies in favor of hyper reactive antibodies, could be the cause of the massive inflammatory reaction (cytokine storm, coagulopathies, neuropathies) observed in Covid 19 patients or after anti-SarsCoV2 vaccination. This analysis is an invitation to investigate the post-infectious and/or post-vaccination adverse phenomena in the light of xenosialization as a key to understanding the severe post viral and post vaccine complications, including SARS-CoV2 infection or related vaccination.

IFIH1 loss-of-function predisposes to inflammatory and SARS-CoV-2-related infectious diseases (preprint)

The IFIH1 gene, encoding melanoma differentiation-associated protein 5 (MDA5), is an indispensable innate immune regulator involved in the early detection of viral infections. Previous studies described MDA5 dysregulation linking it to weakened immunological responses, and increased susceptibility to microbial infections and autoimmune disorders. Monoallelic gain-of-function of the IFIH1 gene has been associated with multisystem disorders, namely Aicardi-Goutieres and Singleton-Merten syndromes, while biallelic loss of this gene causes immunodeficiency. In this study, nine patients suffering from different cases of recurrent infections, inflammatory diseases, severe COVID-19, or multisystem inflammatory syndrome in children (MIS-C) were identified with putative loss-of-function IFIH1 variants by whole exome sequencing. All patients revealed signs of lymphopenia and an increase in inflammatory markers, including CRP, amyloid A, ferritin, and IL-6. One patient with a pathogenic homozygous variant c.2807+1G>A was the most severe case showing immunodeficiency and glomerulonephritis. The c.1641+1G>C variant was identified in the heterozygous state in patients suffering from periodic fever, COVID-19, or MIS-C, while the c.2016delA variant was identified in two patients with inflammatory bowel disease or MIS-C. Expression analysis showed that PBMCs of one patient with a c.2016delA variant had a significant decrease in ISG15, IFNA and IFNG transcript levels, compared to normal PBMCs, upon stimulation with poly(I:C), suggesting that MDA5 receptor truncation disrupts the immune response. Our findings accentuate the implication of rare monogenic IFIH1 loss-of-function variants in altering the immune response, and severely predisposing patients to inflammatory and infectious diseases, including SARS-CoV-2 related disorders.

COVID-19 vaccines and autoimmune disorders: A scoping review protocol (preprint)

Background - Two years into the global vaccination program, important questions about the association between COVID-19 vaccines and autoimmune diseases have arisen. A growing number of reports have documented associations between COVID-19 vaccination and autoimmunity, suggesting, for example, a causal link between vaccination and new-onset and/or relapsing autoimmune disorders such as type 1 diabetes mellitus, rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, Graves disease, and Hashimoto s thyroiditis. These autoimmune phenomena have occurred with various COVID-19 vaccines and research is required to elucidate the underlying mechanisms and causal directions, for example, whether persons with no history of autoimmune disorders may experience them upon vaccination or persons with autoimmune disorders may experience exacerbation or new adverse events post-vaccination. Methods and analysis - Specific objectives of this scoping review will address the following questions: Can COVID-19 vaccination trigger and/or exacerbate autoimmune disorders? Are persons with autoimmune disorders at higher risk of experiencing additional autoimmune disorders? What are the mechanisms connecting autoimmune disorders with COVID-19 vaccination? Can COVID-19 vaccination interact with immunosuppressive therapy in persons with autoimmune disorders? Does the risk of autoimmune disorders following COVID-19 vaccination differ by vaccine type, age, gender, or other still unidentified characteristics (e.g., SES)? What is the consensus of care concerning COVID-19 vaccination in persons with autoimmune disorders and what evidence informs it? Our review will follow Arksey and O Malley s (2005) framework, enhanced by Levac et al. s team-based approach (2010), and adhering to the recommendations of the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist. To capture the broadest range of perspectives on the phenomenon of interest, data will be synthesized through numerical summaries describing general characteristics of included studies and thematic analysis. Subgroup analysis of primary outcomes will be performed to compare findings according to 1) the previous existence of autoimmune disorder, 2) the presence of relevant co-morbidities, 3) vaccine type; and other relevant factors that we may encounter as the research proceeds. Significance - COVID-19 has triggered the largest vaccination campaign in history, targeting literally the global human community. Drug safety is a crucial aspect of any medical intervention, critical to a proper assessment of the balance of risks and benefits. Our investigation should yield information useful to improve medical and public health practice in multiple ways, including assisting in clinical decision-making, policy development, and ethical medical practice.

Age- and sex-specific differences in immune responses to BNT162b2 COVID-19 and live-attenuated influenza vaccines in UK adolescents (preprint)

Key to understanding COVID-19 correlates of protection is assessing vaccine-induced immunity in different demographic groups. Sex- and age-specific immune differences have a wide impact on outcomes from infections and immunisations. Typically, adult females make stronger immune responses and have better disease outcomes but suffer more adverse events following vaccination and are more prone to autoimmune disease. To understand better the mechanisms underlying these differences in vaccine responses, we studied immune responses to two doses of BNT162b2 Pfizer COVID-19 vaccine in an adolescent cohort (n=34, ages 12-16), an age group previously shown to make significantly greater immune responses to the same vaccine compared to young adults. At the same time, we were able to evaluate immune responses to the co-administered live attenuated influenza vaccine, which has been shown to induce stronger immune responses in adult females. Blood samples from 34 adolescents taken pre- and post-vaccination with COVID-19 and influenza vaccines were assayed for SARS-CoV-2-specific IgG and neutralising antibodies, and cellular immunity specific for SARS-CoV-2 and endemic betacoronaviruses. IgG targeting influenza lineages contained in the influenza vaccine was also assessed. As previously demonstrated, total IgG responses to SARS-CoV-2 Spike antigens were significantly higher among vaccinated adolescents compared to adults (aged 32-52) who received the BNT162b2 vaccine (comparing infection-naive, 49,696 vs 33,339; p=0.03; comparing SARS-CoV-2 previously-infected, 743,691 vs 269,985; p<0.0001) by MSD v-plex assay. However, unexpectedly, antibody responses to BNT162b2 and the live-attenuated influenza vaccine were not higher among female adolescents compared to males; among infection-naive adolescents, antibody responses to BNT162b2 were higher in males than females (62,270 vs 36,951 p=0.008). No sex difference was identified in vaccinated adults. These unexpected findings may result from the introduction of novel mRNA vaccination platforms, generating patterns of immunity divergent from established trends, and providing new insights into what might be protective following COVID-19 vaccination.

MTHFR and LC, CFS, POTS, MCAS, SIBO, EDS: Methylating the Alphabet (preprint)

Long Covid (LC), Chronic Fatigue Syndrome (CFS), Postural Orthostatic Tachycardia Syndrome (POTS), Mast Cell Activation Syndrome (MCAS), Small Intestine Bacterial Overgrowth (SIBO), and Ehlers-Danlos Syndrome (EDS) are all loosely connected, some poorly defined, some with overlapping symptoms. The female preponderance, the prominence of fatigue and chronic inflammation, and methylenetetrahydrofolate reductase (MTHFR) abnormalities may connect them all. Indeed differential methylation may lie at the root. Two - EDS and MTHFR - are genetic. But epigenetic factors may ultimately determine their phenotypic expression. Oxidative stress, overloaded mitochondria, an antioxidant and nutrient shortfall, and suboptimal gut microbiome appear to be the primary determinants. A deep dive into the folate and methionine cycles is undertaken in an attempt to connect these syndromes. The active forms of vitamin D and vitamins B2,3,6,9,12 are shown to be biochemically integral to optimal methylation and control of the epigenome. Their status largely determines the symptoms of abnormal MTHFR in all its phenotypes. The wider implications for aging, cancer, cardiovascular disease, neurodegenerative disease, and autoimmune disease are briefly explored.

Demography, hygiene and previous disease prevalence as plausible risk factors associated with Covid-19 deaths across Indian states (preprint)

Severity of Covid-19 diseases has been disproportionate with higher case-fatality ratio affecting developed nations. In India, states with higher income have reported more number of deaths compared to lower income states. The global burden of diseases India 2019 and the National Health Profile 2019 data was used to draw correlations with Covid-19 mortality at two different dates of peak Covid-19 cases in India. We explored correlation of mortality in different states of India with prevalence of different diseases, demography, development, sanitation etc. The study found a positive correlation with known demographic parameters such as percentage of elderly population(spearman correlation coefficient(rho) =0.44 and 0.46 with 1st and 2nd peak respectively). Similarly, percentage urbanization was seen to correlate well with mortality(rho=0.71 and 0.57) suggesting Covid-19 to be a predominantly urban disease. Prevalence of Autoimmune diseases, and Cancer show higher correlation with deaths. A surprising positive correlation emerged between improved sanitation parameters, such as closed drainage and indoor toilets, with COVID-19 deaths. Overall the multivariate regression model achieved by combining demography, sanitation, autoimmune diseases and cancer gave us the best prediction for Covid-19 mortality(adjusted R square value of 0.71 with peak 1 and 0.85 with peak 2). Analysis of the Covid-19 related data seems to indicate that as the wealth of a state increases, the state urban landscape changes often leading to better sanitation facilities. The lifestyle and prevalence to autoimmune diseases as well as cancer also increases. However, this may affect the ability of state to fight pandemics due to lower exposure to pathogens and immune training.

COVID-19 Impact in Crohn Disease Patients Underwent Autologous Hematopoietic Stem Cell Transplantation (preprint)

SARS COV 2 is the virus responsible for COVID-19, a disease that has been blamed for inducing or exacerbating symptoms in patients with autoimmune diseases. Crohn's disease (CD) is an inflammatory bowel disease that affects genetically susceptible patients who develop an abnormal mucosal immune response to the intestinal microbiota. Patients who underwent Hematopoietic Stem cell Transplantation are considered at risk for COVID-19. The objective of this report was to describe for the first time the impact of COVID-19 in a group of 50 patients with Crohn's Disease (CD, 28 females, and 22 male) with a mean age of 38 years, previously submitted to Autologous, non-myeloablative, Hematopoietic Stem Cell Transplantation (Auto HSCT) between 2013 and 2021. In this series, 19 patients were diagnosed with positive COVID-19. In two (2) patients there was a report of the occurrence of two infectious episodes. Parameters related to HSCT, such as time elapsed since the procedure, vaccination status, CD status before and after infection, and clinical manifestations resulting from COVID-19, were evaluated. Among the patients with COVID-19, in three, submitted to Auto HSCT less than six (6) months ago, there was a change in the CD status, and one of them, in addition to the CD symptoms, started to present thyroid impairment with positive anti-TPO. Only one of the patients required hospitalization for five days to treat COVID-19 and remained in CD clinical remission. Nine patients reported late symptoms that may be related to COVID-19. There were no deaths, and the statistical evaluation of the series of COVID-19 patients after HSCT and those who did not present an infectious episode did not present significant data regarding the analyzed parameters. Despite the change in CD status in three patients and the presence of nine patients with late symptoms, we can conclude that there was no significant adverse impact concerning COVID-19 in the evaluated patients who underwent HSCT to treat CD. Key Words: Inflammatory bowel disease, Crohn Disease, SARs COV 2, COVID - 19, Autologous Hematopoietic Stem Cell Transplantation, Stem Cell Therapy.

No genetic causal association between systemic lupus erythematosus and COVID-19.

Objective: Emerging evidence suggests an increased prevalence of coronavirus disease 2019 (COVID-19) in patients with systemic lupus erythematosus (SLE), the prototype of autoimmune disease, compared to the general population. However, the conclusions were inconsistent, and the causal relationship between COVID-19 and SLE remains unknown. Methods: In this study, we aimed to evaluate the bidirectional causal relationship between COVID-19 and SLE using bidirectional Mendelian randomization (MR) analysis, including MR-Egger, weighted median, weighted mode, and the inverse variance weighting (IVW) method. Results: The results of IVW showed a negative effect of SLE on severe COVID-19 (OR = 0.962, p = 0.040) and COVID-19 infection (OR = 0.988, p = 0.025), which disappeared after Bonferroni correction. No causal effect of SLE on hospitalized COVID-19 was observed (OR = 0.983, p = 0.148). In the reverse analysis, no causal effects of severe COVID-19 infection (OR = 1.045, p = 0.664), hospitalized COVID-19 (OR = 0.872, p = 0.109), and COVID-19 infection (OR = 0.943, p = 0.811) on SLE were found. Conclusion: The findings of our bidirectional causal inference analysis did not support a genetically predicted causal relationship between SLE and COVID-19; thus, their association observed in previous observational studies may have been caused by confounding factors.

Mapping current status and emerging trends in NETosis: A bibliometric study.

BACKGROUND: NETosis is a critical innate immune mechanism of neutrophils that contributes to the accelerated progression of autoimmune diseases, thrombosis, cancer, and coronavirus disease 2019 (COVID-19). This study qualitatively and quantitatively analyzed the relevant literature by bibliometric methods in order to provide a more comprehensive and objective view of the knowledge dynamics in the field. METHODS: The literature on NETosis was downloaded from the Web of Science Core Collection, analyzed with VOSviewer, CiteSpace, and Microsoft for co-authorship, co-occurrence, and co-citation analysis. RESULTS: In the field of NETosis, the United States was the most influential countries. Harvard University was the most active institutions. Mariana J. Kaplan and Brinkmann V were, respectively, the most prolific and most co-cited authors. Frontiers in Immunology, Journal of Immunology, Plos One, Blood, Science, Journal of Cell Biology, and Nature Medicine were the most influential journals. The top 15 keywords are associated with immunological and NETosis formation mechanisms. The keywords with the strongest burst detection were mainly related to COVID-19 (coronavirus, ACE2, SARS coronavirus, cytokine storm, pneumonia, neutrophil to lymphocyte ratio), and cancer (circulating tumor cell). CONCLUSION: Research on NETosis is currently booming. The mechanism of NETosis and its role in innate immunity, autoimmune diseases, especially systemic lupus erythematosus and rheumatoid arthritis, and thrombosis are the focus of research in the field of NETosis. A future study will concentrate on the function of NETosis in COVID-19 and recurrent metastasis of cancer.

Post-acute COVID-19 in three doses vaccinated autoimmune rheumatic diseases patients: frequency and pattern of this condition.

BACKGROUND: Data on post-acute COVID-19 in autoimmune rheumatic diseases (ARD) are scarce, focusing on a single disease, with variable definitions of this condition and time of vaccination. The aim of this study was to evaluate the frequency and pattern of post-acute COVID-19 in vaccinated patients with ARD using established diagnosis criteria. METHODS: Retrospective evaluation of a prospective cohort of 108 ARD patients and 32 non-ARD controls, diagnosed with SARS-CoV-2 infection (RT-PCR/antigen test) after the third dose of the CoronaVac vaccine. Post-acute COVID-19 (≥ 4 weeks and > 12 weeks of SARS-CoV-2 symptoms) were registered according to the established international criteria. RESULTS: ARD patients and non-ARD controls, balanced for age and sex, had high and comparable frequencies of ≥ 4 weeks post-acute COVID-19 (58.3% vs. 53.1%, p = 0.6854) and > 12 weeks post-acute COVID-19 (39.8% vs. 46.9%, p = 0.5419). Regarding ≥ 4 weeks post-acute COVID-19, frequencies of ≥ 3 symptoms were similar in ARD and non-ARD controls (54% vs. 41.2%, p = 0.7886), and this was also similar in > 12 weeks post-acute COVID-19 (68.3% vs. 88.2%, p = 0.1322). Further analysis of the risk factors for ≥ 4 weeks post-acute COVID-19 in ARD patients revealed that age, sex, clinical severity of COVID-19, reinfection, and autoimmune diseases were not associated with this condition (p > 0.05). The clinical manifestations of post-acute COVID-19 were similar in both groups (p > 0.05), with fatigue and memory loss being the most frequent manifestations. CONCLUSION: We provide novel data demonstrating that immune/inflammatory ARD disturbances after third dose vaccination do not seem to be a major determinant of post-acute COVID-19 since its pattern is very similar to that of the general population. Clinical Trials platform (NCT04754698).

Autoantibodies to Interferons in Infectious Diseases.

Anti-cytokine autoantibodies and, in particular, anti-type I interferons are increasingly described in association with immunodeficient, autoimmune, and immune-dysregulated conditions. Their presence in otherwise healthy individuals may result in a phenotype characterized by a predisposition to infections with several agents. For instance, anti-type I interferon autoantibodies are implicated in Coronavirus Disease 19 (COVID-19) pathogenesis and found preferentially in patients with critical disease. However, autoantibodies were also described in the serum of patients with viral, bacterial, and fungal infections not associated with COVID-19. In this review, we provide an overview of anti-cytokine autoantibodies identified to date and their clinical associations; we also discuss whether they can act as enemies or friends, i.e., are capable of acting in a beneficial or harmful way, and if they may be linked to gender or immunosenescence. Understanding the mechanisms underlying the production of autoantibodies could improve the approach to treating some infections, focusing not only on pathogens, but also on the possibility of a low degree of autoimmunity in patients.

Autoimmune/inflammatory syndrome induced by adjuvants in a woman with Hashimoto thyroiditis and familial autoimmunity-a case report and literature review.

Introduction: Autoimmune/inflammatory syndrome induced by adjuvants (ASIA) consists of a wide spectrum of symptoms and immunological features that are believed to develop in predisposed individuals after exposure to an adjuvant, including a silicone breast implant (SBI). Different autoimmune diseases (AIDs) have been associated with ASIA, but ASIA development after SBI in women with Hashimoto thyroiditis (HT) and familial autoimmunity has rarely been described. Case report: A 37-year-old woman presented in 2019 with arthralgia, sicca symptoms, fatigue, + antinuclear antibody (ANA), + anti SSA, and + anticardiolipin Immunoglobulin G (IgG) antibodies. She was diagnosed with HT and vitamin D deficiency in 2012. The familial autoimmunity was present: the patient's mother had been diagnosed with systemic lupus erythematosus and secondary Sjogren's syndrome and her grandmother with cutaneous lupus and pernicious anemia. In 2017, the patient had a cosmetic SBI procedure that was complicated by repeated right breast capsulitis. After 2 years of irregular visits due to COVID-19, she presented with + ANA, + anticentromere antibodies both in sera and seroma, sicca syndrome, arthralgias, twinkling in extremities, abnormal capillaroscopic findings, and reduced diffusing capacity of the lungs for carbon monoxide. She was diagnosed with ASIA, and antimalarial and corticosteroid therapy were introduced. Conclusion: In patients with HT and familial autoimmunity, SBI should be carefully considered due to the possibility of ASIA development. Hashimoto thyroiditis, familial autoimmunity, and ASIA seem to be interconnected in the complex mosaic of autoimmunity in predisposed individuals.

Mapping interindividual dynamics of innate immune response at single-cell resolution.

Common genetic variants across individuals modulate the cellular response to pathogens and are implicated in diverse immune pathologies, yet how they dynamically alter the response upon infection is not well understood. Here, we triggered antiviral responses in human fibroblasts from 68 healthy donors, and profiled tens of thousands of cells using single-cell RNA-sequencing. We developed GASPACHO (GAuSsian Processes for Association mapping leveraging Cell HeterOgeneity), a statistical approach designed to identify nonlinear dynamic genetic effects across transcriptional trajectories of cells. This approach identified 1,275 expression quantitative trait loci (local false discovery rate 10%) that manifested during the responses, many of which were colocalized with susceptibility loci identified by genome-wide association studies of infectious and autoimmune diseases, including the OAS1 splicing quantitative trait locus in a COVID-19 susceptibility locus. In summary, our analytical approach provides a unique framework for delineation of the genetic variants that shape a wide spectrum of transcriptional responses at single-cell resolution.

NETosis as an oncologic therapeutic target: a mini review.

Neutrophil Extracellular Traps (NETs) are a key form of pro-inflammatory cell death of neutrophils characterized by the extrusion of extracellular webs of DNA containing bactericidal killing enzymes. NETosis is heavily implicated as a key driver of host damage in autoimmune diseases where injurious release of proinflammatory enzymes damage surrounding tissue and releases 70 known autoantigens. Recent evidence shows that both neutrophils and NETosis have a role to play in carcinogenesis, both indirectly through triggering DNA damage through inflammation, and directly contributing to a pro-tumorigenic tumor microenvironment. In this mini-review, we summarize the current knowledge of the various mechanisms of interaction and influence between neutrophils, with particular attention to NETosis, and cancer cells. We will also highlight the potential avenues thus far explored where we can intercept these processes, with the aim of identifying promising prospective targets in cancer treatment to be explored in further studies.

High fatigue scores in patients with idiopathic inflammatory myopathies: a multigroup comparative study from the COVAD e-survey.

Idiopathic inflammatory myopathies (IIMs) confer a significant risk of disability and poor quality of life, though fatigue, an important contributing factor, remains under-reported in these individuals. We aimed to compare and analyze differences in visual analog scale (VAS) scores (0-10 cm) for fatigue (VAS-F) in patients with IIMs, non-IIM systemic autoimmune diseases (SAIDs), and healthy controls (HCs). We performed a cross-sectional analysis of the data from the COVID-19 Vaccination in Autoimmune Diseases (COVAD) international patient self-reported e-survey. The COVAD survey was circulated from December 2020 to August 2021, and details including demographics, COVID-19 history, vaccination details, SAID details, global health, and functional status were collected from adult patients having received at least one COVID-19 vaccine dose. Fatigue experienced 1 week prior to survey completion was assessed using a single-item 10 cm VAS. Determinants of fatigue were analyzed in regression models. Six thousand nine hundred and eighty-eight respondents (mean age 43.8 years, 72% female; 55% White) were included in the analysis. The overall VAS-F score was 3 (IQR 1-6). Patients with IIMs had similar fatigue scores (5, IQR 3-7) to non-IIM SAIDs [5 (IQR 2-7)], but higher compared to HCs (2, IQR 1-5; P < 0.001), regardless of disease activity. In adjusted analysis, higher VAS-F scores were seen in females (reference female; coefficient -0.17; 95%CI -0.21 to -13; P < 0.001) and Caucasians (reference Caucasians; coefficient -0.22; 95%CI -0.30 to -0.14; P < 0.001 for Asians and coefficient -0.08; 95%CI -0.13 to 0.30; P = 0.003 for Hispanics) in our cohort. Our study found that patients with IIMs exhibit considerable fatigue, similar to other SAIDs and higher than healthy individuals. Women and Caucasians experience greater fatigue scores, allowing identification of stratified groups for optimized multidisciplinary care and improve outcomes such as quality of life.