BackgroundNeuroinflammation and systemic immune dysregulation are increasingly recognized as key contributors to secondary brain injury after aneurysmal subarachnoid hemorrhage (aSAH). However, the temporal relationship between circulating cytokine responses and innate-like lymphocyte populations, particularly mucosal-associated invariant T (MAIT) cells, remains poorly characterized.MethodsIn this prospective observational study, peripheral blood cytokine profiles were longitudinally analyzed in 48 patients with aSAH on days 1, 5, and 9 after ictus and compared with healthy controls. Serum concentrations of IL-6, IL-7, IL-12p40, IL-12p70, IL-15, IL-17A, IL-18, IL-22, IP-10, and CXCL-9 were measured using multiplex immunoassay. Flow cytometric immunophenotyping was performed in a subgroup of 16 patients to evaluate MAIT cells, NK cells, γδ T cells, iNKT cells, and NKT-like cells. Associations between immune parameters and 3-month functional outcome were also assessed.ResultsPatients with aSAH demonstrated persistently elevated IL-6, IL-18, and IL-15 levels across all examined time points, while IL-7, IL-12p40, IP-10, and CXCL-9 showed delayed increases during the subacute phase. IL-6 and IL-15 concentrations were significantly higher in patients with unfavorable outcome, whereas IL-22 levels were increased in patients with favorable recovery. However, these associations were not independent of disease severity after adjustment for WFNS score and age. Flow cytometry revealed a persistent reduction in circulating MAIT-cell frequencies following aSAH, while other innate-like lymphocyte populations remained largely unchanged. DN MAIT-cell frequencies demonstrated significant negative correlations with circulating IL-18 levels across all examined time points.ConclusionaSAH is associated with sustained systemic inflammatory activation and selective alterations of MAIT-cell populations. Although several cytokines were associated with functional outcome in univariate analyses, these associations were attenuated after adjustment for WFNS score and age, suggesting that they primarily reflect disease severity rather than independent prognostic effects. The observed relationship between MAIT-cell dysregulation and IL-18–associated inflammation provides further evidence of altered innate-like immune responses following aSAH.

Background: Serum C–C motif chemokine ligand 18 (seCCL18) in systemic sclerosis (SSc) has been primarily associated with progressive interstitial lung disease (SSc-ILD) and mortality. However, its relationship with non-pulmonary organ involvement, disease activity, and long-term outcome has not been comprehensively evaluated. We therefore examined the clinical relevance of seCCL18 in a single-center SSc cohort. Methods: A total of 151 patients with SSc (83 diffuse cutaneous (dcSSc), 68 limited cutaneous SSc (lcSSc); median (IQR) disease duration: 9 (4;16) years) and 47 age- and sex-matched healthy controls (HCs) were enrolled. Serum CCL18 concentrations were measured by enzyme-linked immunosorbent assay. Elevated seCCL18 was defined as >130 ng/mL (mean + 2 SD of the healthy control group). Organ involvement and disease activity (EUSTAR Activity Index, EUSTAR-AI) were assessed at baseline, while survival was analysed longitudinally. Results: Patients with SSc had significantly higher seCCL18 levels than HCs (mean ± SD: 99.9 ± 43.2 vs. 75.0 ± 27.5 ng/mL, p < 0.01). Elevated seCCL18 was associated with SSc-ILD (81.1% vs. 60.5%, p = 0.022), reduced forced vital capacity (FVC < 70%: 16.2% vs. 3.5%, p = 0.006), and reduced diffusing capacity for carbon monoxide (DLCO < 70%: 80.6% vs. 54.4%, p = 0.005). Higher seCCL18 levels were observed in patients with myocardial disease (104.8 ± 41.8 vs. 83.8 ± 44.2 ng/mL, p = 0.008), left ventricular diastolic dysfunction (107.1 ± 40.5 vs. 84.5 ± 45.0 ng/mL, p < 0.001), and oesophageal involvement (110.7 ± 38.3 vs. 93.3 ± 43.1 ng/mL, p = 0.009). SeCCL18 levels above the cut-off were more frequently associated with tendon friction rubs (51.4% vs. 27.4%, p = 0.007), active disease (EUSTAR-AI ≥ 2.5: 73% vs. 44%, p = 0.002), and elevated inflammatory markers (CRP > 5 mg/L: 51.4% vs. 19.3%, p < 0.001; ESR > 28 mm/h: 37.8% vs. 18.4%, p = 0.015). During a median follow-up of 87 months, 22 patients (15%) died. Elevated baseline seCCL18 predicted poorer survival in univariate analysis (log-rank p = 0.013) and remained an independent predictor of mortality in multivariable Cox regression (HR 1.789; 95% CI 1.133–2.824; p = 0.013), together with declining DLCO and reduced six-minute walk test performance. Conclusions: Elevated seCCL18 may identify patients with systemic sclerosis who exhibit a more severe multisystem phenotype, including cardiopulmonary, gastrointestinal, and musculoskeletal involvement, increased inflammatory activity, and reduced long-term survival. These findings suggest that seCCL18 may have some clinical utility as a prognostic biomarker reflecting widespread disease involvement beyond the lungs, even in patients with long-standing disease; however, the lack of an established cut-off value requires further validation in prospective, multicentre studies.

IntroductionPsycho-neuro-immunological research examines the relationship between mental disorders and immune abnormalities. Chronic, low-grade inflammation was found to be associated with depression and suicidal behavior; however findings are inconsistent due to methodological differences. This study aims to identify peripheral immunological parameters that may characterize patients with recent suicide attempt.Method100 psychiatric in-patients treated with depressive disorders with or without recent suicide attempt were investigated. Demographic data, severity of depression, suicide risk and peripheral immunological parameters were recorded. Descriptive statistics and logistic regression analyses were carried out to assess differences between the recent suicide attempter and the non-suicidal groups.ResultsThere were no significant differences between recent and non-recent suicide attempters in age, gender, or depression severity. However, recent suicide attempters exhibited higher levels of leukocytes, neutrophils, eosinophils, monocytes, Neutrophil-to-Lymphocyte Ratio (NLR) and Monocyte-to-Lymphocyte Ratio (MLR). NLR and MLR remained elevated in the recent suicide attempter group after adjusting for confounders. Significant positive correlations were observed between NLR, MLR, Platelet-to-Lymphocyte Ratio (PLR), and platelet values, but not with CRP, while depression scores correlated negatively with PLR, NLR, and MLR.ConclusionAlthough elevated low-grade inflammatory parameters, particularly NLR and MLR, were observed in depressed patients with a recent suicide attempt, this study does not provide conclusive evidence for a direct association between suicide attempts and the investigated immune markers. Further research is needed to clarify this relationship between low-grade immune parameters and acute suicide attempts, to elucidate potential causal mechanisms, and to determine their relevance and clinical applicability as biomarkers of suicidal behavior.

IntroductionNatural autoantibodies (nAAbs) contribute to immune homeostasis and may be altered in patients with autoimmune diseases. While anti-heat shock protein (Hsp) antibodies have been previously described in juvenile idiopathic arthritis (JIA), their relationship with disease severity and treatment effects during remission remains unclear. This study aimed to measure the serum levels of IgM and IgG nAbs against heat shock protein (Hsp) 60 and Hsp70 in children with JIA in remission (mean age: 7.41 years, range:1.27-14.54 years) and to explore their associations with disease subtype, severity, and treatment.MethodsSerum samples from 47 children with JIA in remission and 22 apparently healthy controls (HC) were analyzed. Patient groups were stratified according to the treatment regimen (methotrexate monotherapy versus methotrexate plus adalimumab) and disease subtype and severity. Anti-Hsp60 and anti-Hsp70 IgM and IgG antibodies were measured using an in-house indirect ELISA.ResultsNo significant differences in anti-Hsp60 or anti-Hsp70 nAAb levels were observed between patients with JIA and apparently healthy controls or between treatment groups. However, severity-based analyses revealed significantly lower anti-Hsp60 and anti-Hsp70 IgM levels in patients with polyarticular JIA than in those with milder oligoarticular forms and in apparently healthy controls. No significant differences were observed in the anti-Hsp60 or anti-Hsp70 IgG levels.ConclusionReduced levels of natural IgM autoantibodies against Hsp60 and Hsp70 are associated with more severe JIA phenotypes during remission, supporting the potential immunoregulatory and protective roles of natural IgM autoantibodies in JIA.

Natural autoantibodies (nAAbs) recognize self-antigens and are an important component of the immune system, having evolved from invertebrates to vertebrates, and are viewed as stable byproducts of immune function and essential players in health and disease. Initially characterized by their conserved nature and multi-reactivity, primarily as IgM isotypes, nAAbs are now recognized for their adaptability in response to infections and vaccinations, bridging innate and adaptive immunity. The nAAbs and the cellular elements, such as γδ T, iNKT, and MAIT cells, of the natural immune system perform a primary defense network with moderate antigen-specificity. This comprehensive literature review was conducted to analyze the role of natural autoantibodies (nAAbs) in health and disease. The review focused on research published over the past 40 years, emphasizing studies related to infectious diseases, vaccinations, and autoimmune disorders. Recent studies suggest that nAAbs engage in complex interactions in autoimmune diseases, including systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, and type 1 diabetes. Their roles in immunological processes, such as maternal tolerance during pregnancy, further underscore their complexity. Emerging evidence indicates that nAAbs and the cellular elements of the natural immune system may contribute to both disease pathogenesis and protective mechanisms, highlighting their dual nature. Continued research on nAAbs is vital for improving our understanding of immune responses and developing therapeutic strategies for autoimmune disorders and infectious diseases.

BACKGROUND:Annual flu vaccination is recommended for children with rheumatic diseases. We investigated the cellular and humoral immune response and safety in pediatric patients that received inactivated influenza vaccines. METHODS:This is a comparative study of in 41 children with juvenile idiopathic arthritis (JIA) receiving influenza vaccination while being treated with methotrexate (MTX) or biological therapy. The influenza vaccination was administered as a single dose of trivalent influenza vaccine (TIV). Serological tests to monitor seroconversion and seroprotection were performed at baseline and at 4 as well as 12 weeks after vaccination. RESULTS:In all of the 41 children with JIA and the 22 healthy children seroconversion and seroprotection were observed for Influenza A. For Influenza B, no adequate seroconversion rates were not detected in any of the groups studied. No significant differences were observed in lymphocyte subpopulations when analysing time points and groups simultaneously. There were no relapses or cases of influenza infection after the vaccination. Our findings do not suggest non-specific immune activation following vaccination based on the distribution and quantity of the lymphocyte subsets that were investigated. CONCLUSION:The present study demonstrates adequate seroprotection rates against influenza A in immunosuppressed children with JIA. The trivalent vaccine had good immunogenicity and was safe to use in both JIA treatment groups.

Suicide is an unresolved issue in psychiatry to this day. Suicide risk (SR) is particularly high for psychiatric patients with bipolar I disorder (BD). Recent studies suggest an immunological dysregulation in the background. In our retrospective study, we investigated laboratory parameters of BD in-patients (n = 116) between January 2020 and June 2024. Data was collected regarding the following parameters: white blood cell, neutrophil, lymphocyte, monocyte and platelet count, monocyte-to-lymphocyte (MLR), neutrophil-to-lymphocyte (NLR) and platelet-to-lymphocyte ratio (PLR), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), red blood cell distribution width (RDW) and mean platelet volume (MPV). Individuals with recent (≤ 48 hours prior) suicide attempt (SA) (n = 21) and with past (> 48 hours prior) SA (n = 16) represented the high SR group (n = 37). BD patients with no history of SA composed the intermediate SR group (n = 79). We found a significant increase in MLR, monocyte count, CRP and ESR in patients with recent SA compared to those with no history of SA. Comparing high and intermediate SR patients, MLR, monocyte count, CRP and ESR remained elevated in the former group. As implied by previous research, immunological mechanisms may contribute to the emergence of suicidality. Investigating BD patients as the subgroup at significant risk, changes in certain inflammatory markers further strengthen the assumption of immunological processes in the background of suicidality, and these parameters may serve as potential future biomarkers of SR.

Purpose:Despite the worldwide decrease in the incidence of serious pneumococcal infections following the introduction of the 13-valent pneumococcal conjugate vaccines (PCV13), invasive infections still occur. This study aimed to investigate the immunological function of children with severe parapneumonic effusion (PPE) both during their hospitalization and after full recovery. Methods:This was a prospective, single-center study. Children with PPE were admitted to our clinic between 1 January 2011 and 30 June 2023, and participated in the study. Due to the severity of the effusion, all PPE cases required thoracic drainage and some children also underwent fibrinolysis and/or video-assisted thoracoscopic surgery. Demographic and clinical data and laboratory results were collected at admission. Extended immunological testing was performed at the time of clinical admission and again 6-8 weeks after discharge. Results:A total of 66 episodes of PPE were identified. During hospitalization, one patient was diagnosed with human immunodeficiency virus infection and another with immunoglobulin A deficiency. Extended immunological evaluation was performed during follow-up in 49 patients. Within this cohort, seven patients were diagnosed with mannose-binding lectin deficiency and three with specific antibody deficiency. In total, immune dysfunction was confirmed in 12 patients. When comparing the immunocompromised and non-immunocompromised groups, the duration of hospitalization was longer in the immunocompromised group, with no other differences observed. Conclusion:Although the incidence of severe PPE has declined since the introduction of PCV13, immunological evaluation remains essential for identifying underlying immunodeficiencies. Despite vaccination, screening patients with PPE for immune dysfunction is crucial. Early diagnosis and timely treatment can help prevent organ damage and reduce long-term morbidity.

Aneurysmal subarachnoid hemorrhage (aSAH) is a serious condition complicated by delayed cerebral ischemia (DCI), where inflammation plays a key role. Although altered gut permeability is noted in other conditions, its significance in aSAH remains unclear. Fatty acid-binding protein (FABP-I), lipopolysaccharide-binding protein (LBP), and soluble CD-14 (sCD-14) are established markers of barrier dysfunction. This study investigates gut permeability marker changes in early and late aSAH phases. The study included 177 aSAH patients and 100 controls. Serum samples were collected on days 1 (D1) and 9 (D9) after ictus. FABP-I, LBP, and sCD-14 levels were measured via ELISA, and clinical data were recorded. Outcomes were assessed using the 90-day modified Rankin scale (mRS 0-3 = favorable outcome). Serum FABP-I was significantly lower in aSAH patients (p < 0.05), while LBP and sCD-14 were higher (p < 0.001) compared to controls. FABP-I did not differ between outcome groups, but LBP and sCD-14 were significantly elevated in unfavorable outcomes (p < 0.001). These markers differed in patients without in-hospital infection, with higher levels noted in DCI patients during the later phase (p < 0.05). In aSAH patients without infection, differences in LBP and sCD-14 levels between outcome groups suggest potential endotoxin release from microbial systems, contributing to neuroinflammation and influencing outcomes.

Suicide is the most severe complication of major depressive disorder (MDD). Novel research assumes the role of immunological dysregulation in the background – several studies have reported alterations in the number of inflammatory cells related to both MDD and suicidality. There are currently no objective, routinely measured parameters to indicate suicidal vulnerability. However, altered inflammatory cell numbers and ratios have been proposed as potential biomarkers of suicide risk (SR). The present research aims to examine changes of these values related to increased SR in MDD as an assumed inflammatory state. We investigated laboratory parameters of psychiatric in-patients diagnosed with MDD (n = 101) retrospectively. Individuals with recent suicide attempt (SA) (n = 22) and with past SA (n = 19) represented the high SR group. MDD patients with no history of SA (n = 60) composed the intermediate SR group. We compared the number of neutrophil granulocytes, monocytes, lymphocytes, platelets, white blood cell count (WBC), neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte (MLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume (MPV), red blood cell distribution width (RDW) and erythrocyte sedimentation rate (ESR). Furthermore, we evaluated alterations of these parameters related to antidepressant (AD) and antipsychotic (AP) treatment, which have been proved to have anti-inflammatory effects. We found a significant increase in neutrophil granulocyte count, NLR, monocyte count, MLR, WBC and ESR in patients with recent SA compared to patients with no history of SA. Moreover, there was a significant elevation in monocyte count, MLR, ESR and RDW in patients with high SR compared to patients with intermediate SR. AD treatment resulted in a significant decrease in neutrophil granulocyte count and NLR, however, it did not affect monocyte count and MLR. Assuming immunological mechanisms in the background of MDD and suicidality, our findings support the role of NLR as a biomarker of acute SR, though its alterations may be masked by possible anti-inflammatory effects of AD treatment in the long term. However, MLR, a marker exhibiting changes which are not attenuated by pharmacotherapy, may be a possible indicator of both acute and long-term suicidal vulnerability.

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has introduced the medical community to the phenomenon of long COVID, a condition characterized by persistent symptoms following the resolution of the acute phase of infection. Among the myriad of symptoms reported by long COVID sufferers, chronic fatigue, cognitive disturbances, and exercise intolerance are predominant, suggesting systemic alterations beyond the initial viral pathology. Emerging evidence has pointed to mitochondrial dysfunction as a potential underpinning mechanism contributing to the persistence and diversity of long COVID symptoms. This review aims to synthesize current findings related to mitochondrial dysfunction in long COVID, exploring its implications for cellular energy deficits, oxidative stress, immune dysregulation, metabolic disturbances, and endothelial dysfunction. Through a comprehensive analysis of the literature, we highlight the significance of mitochondrial health in the pathophysiology of long COVID, drawing parallels with similar clinical syndromes linked to post-infectious states in other diseases where mitochondrial impairment has been implicated. We discuss potential therapeutic strategies targeting mitochondrial function, including pharmacological interventions, lifestyle modifications, exercise, and dietary approaches, and emphasize the need for further research and collaborative efforts to advance our understanding and management of long COVID. This review underscores the critical role of mitochondrial dysfunction in long COVID and calls for a multidisciplinary approach to address the gaps in our knowledge and treatment options for those affected by this condition.

The function of natural autoantibodies (nAAbs) in maintaining immunological tolerance has been comprehensively explained; however, their function in pregnant patients dealing with autoimmune diseases has not been thoroughly investigated. As Hashimoto’s thyroiditis (HT) is the predominant organ-specific autoimmune condition of women of childbearing age, this study’s objective was to evaluate IgM and IgG nAAbs targeting mitochondrial citrate synthase (CS) and heat shock proteins (Hsp60 and Hsp70) in women diagnosed with HT who were pregnant (HTP). Serum samples collected from HTP and healthy pregnant (HP) women in the first and third trimesters were tested using in-house-developed enzyme-linked immunosorbent assays (ELISAs). Our findings indicate the stability of nAAbs against CS and Hsps throughout the pregnancies of both healthy women and those with HT. However, during both trimesters, HTP patients displayed elevated levels of IgM isotype nAAbs against Hsp60 and Hsp70 compared to HP women, suggesting a regulatory role of IgM nAAbs during the pregnancies of patients with HT. Nonetheless, levels of IgG isotype nAAbs against Hsps were lower solely in the third trimester among HTP patients, resulting in a higher IgM/IgG ratio, which indicates their importance in alterations of the nAAb network during pregnancy in patients with HT.

We aimed to investigate the characteristics of serum metabolomics in aneurysmal subarachnoid hemorrhage patients (aSAH) with different 3-month outcomes (good = modified Rankin score: 0–3 vs. poor = mRS 4–6). We collected serum samples from 46 aSAH patients at 24 (D1) and 168 (D7) hours after injury for analysis by liquid chromatography-mass spectrometry. Ninety-six different metabolites were identified. Groups were compared using multivariate (orthogonal partial least squares discriminant analysis), univariate, and receiving operator characteristic (ROC) methods. We observed a marked decrease in serum homocysteine levels at the late phase (D7) compared to the early phase (D1). At both D1 and D7, mannose and sorbose levels were notably higher, alongside elevated levels of kynurenine (D1) and increased 2-hydroxybutyrate, methyl-galactoside, creatine, xanthosine, p-hydroxyphenylacetate, N-acetylalanine, and N-acetylmethionine (all D7) in the poor outcome group. Conversely, levels of guanidinoacetate (D7) and several amino acids (both D1 and D7) were significantly lower in patients with poor outcomes. Our results indicate significant changes in energy metabolism, shifting towards ketosis and alternative energy sources, both in the early and late phases, even with adequate enteral nutrition, particularly in patients with poor outcomes. The early activation of the kynurenine pathway may also play a role in this process.

During pregnancy, the maternal immune system must allow and support the growth of the developing placenta while maintaining the integrity of the mother’s body. The trophoblast’s unique HLA signature is a key factor in this physiological process. This study focuses on decidual γδT cell populations and examines their expression of receptors that bind to non-classical HLA molecules, HLA-E and HLA-G. We demonstrate that decidual γδT cell subsets, including Vδ1, Vδ2, and double-negative (DN) Vδ1-/Vδ2- cells express HLA-specific regulatory receptors, such as NKG2C, NKG2A, ILT2, and KIR2DL4, each with varying dominance. Furthermore, decidual γδT cells produce cytokines (G-CSF, FGF2) and cytotoxic mediators (Granulysin, IFN-γ), suggesting functions in placental growth and pathogen defense. However, these processes seem to be controlled by factors other than trophoblast-derived non-classical HLA molecules. These findings indicate that decidual γδT cells have the potential to actively contribute to the maintenance of healthy human pregnancy.

Type I interferon (IFN-I) signaling has been shown to be upregulated in systemic sclerosis (SSc). Dysregulated B-cell functions, including antigen presentation, as well as antibody and cytokine production, all of which may be affected by IFN-I signaling, play an important role in the pathogenesis of the disease. We investigated the IFN-I signature in 71 patients with the more severe form of the disease, diffuse cutaneous SSc (dcSSc), and 33 healthy controls (HCs). Activation via Toll-like receptors (TLRs) can influence the IFN-I signaling cascade; thus, we analyzed the effects of the TLR homologue CD180 ligation on the IFN-I signature in B cells. CD180 stimulation augmented the phosphorylation of signal transducer and activator of transcription 1 (STAT1) in dcSSc B cells (p = 0.0123). The expression of IFN-I receptor (IFNAR1) in non-switched memory B cells producing natural autoantibodies was elevated in dcSSc (p = 0.0109), which was enhanced following anti-CD180 antibody treatment (p = 0.0125). Autoantibodies to IFN-Is (IFN-alpha and omega) correlated (dcSSc p = 0.0003, HC p = 0.0192) and were present at similar levels in B cells from dcSSc and HC, suggesting their regulatory role as natural autoantibodies. It can be concluded that factors other than IFN-alpha may contribute to the elevated IFN-I signature of dcSSc B cells, and one possible candidate is B-cell activation via CD180.

Autoantibody production is a hallmark of systemic sclerosis (SSc) and the most extensively studied role of B cells in the pathogenesis of the disease. However, the potential involvement of innate immune molecules in B-cell dysfunction in SSc is less understood. B-cell activation is an early event in the pathogenesis of SSc and is influenced by complement receptors (CRs) and Toll-like receptors (TLRs), shaping antibody responses. CR2 and CR1 modulate B-cell activation, and the roles of CR3 and CR4 are associated with autoimmune conditions. We investigated the expression of CRs in B cells from patients with the more severe form of the disease, diffuse cutaneous SSc (dcSSc), and the effect of TLR CD180 ligation on their expression. We found no significant difference in the basal expression of CD21 and CD11c in B cells between dcSSc and healthy controls (HCs). However, reduced basal CD11b expression in B cells in dcSSc compared to HCs, accompanied by a decrease in CD35 and an increase in CD11c expression following CD180 ligation may promote plasma cell formation and autoantibody production. Additionally, we searched for correlations between dcSSc-associated anti-DNA topoisomerase I (Scl-70) autoantibody, anti-citrate synthase (CS) natural autoantibody and complement component 3 (C3) levels and found a negative correlation between C3 and anti-CS autoantibody in dcSSc but not in HCs, supporting the hypothesis that natural autoantibodies could activate the complement system contributing to tissue injury in SSc.

Cardiovascular (CV) morbidity and mortality have been associated with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Natural autoantibodies (nAAb) are involved in innate immunity, as well as autoimmunity, inflammation, and atherosclerosis. There have not been any studies assessing the effects of biologics on nAAbs in RA and AS, also in relation to vascular pathophysiology. Fifty-three anti-TNF-treated RA and AS patients were included in a 12-month follow-up study. Anti-citrate synthase (CS) and anti-topoisomerase I fragment 4 (TOPO-F4) IgM and IgG levels were determined by ELISA. Ultrasonography was performed to assess brachial artery flow-mediated vasodilation (FMD), common carotid intima-media thickness (ccIMT), and arterial pulse-wave velocity (PWV). Other variables were also evaluated at baseline and 6 and 12 months after treatment initiation. Anti-TNF therapy improved FMD in RA and PWV in AS and stabilized ccIMT. TNF inhibition increased anti-CS IgM and IgG, and possibly also anti-TOPO-F4 IgG levels. Various correlation analyses revealed that nAAbs might be independently involved in autoimmunity as well as changes in inflammation and vascular pathology over time in biologic-treated patients (p < 0.05). We also found associations between anti-TOPO-F4 IgG and anti-Hsp60 IgG (p < 0.05). Baseline nAAb levels or nAAb level changes might determine changes in CRP, disease activity, FMD, PWV, and ccIMT over time (p < 0.05). The interplay between arthritis and inflammatory atherosclerosis, as well as the effects of anti-TNF biologics on these pathologies, might independently involve nAAbs.

INTRODUCTION:This study investigates the significance of glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCHL-1) in cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS) and peripheral neuropathy (PN). METHODS:We included 41 MS patients, 35 PN patients, and 36 controls across 5 sites. MS patient data included lesion counts, disease activity, albumin quotient, and Expanded Disability Status Scale (EDSS) scores. PN patients included those with acute and chronic inflammatory demyelinating polyneuropathy and sensorimotor neuropathy based on nerve conduction studies. CSF concentrations of GFAP and UCHL-1 were measured using the MILLIPLEX Map Human Neuroscience Magnetic Bead Panel 1. RESULTS:Both GFAP and UCHL-1 levels were significantly higher in the two patient groups compared to controls. In the MS group, GFAP showed a strong correlation with disease duration, EDSS score, non-enhancing lesions, and the CSF/blood albumin quotient. UCHL-1 levels were significantly higher in patients with active disease (gadolinium-enhancing lesions). The combination of UCHL-1 and GFAP improved diagnostic accuracy (AUC 0.895, 95% CI 0.780-1.000) compared to the independent measurement of either marker for indicating Gd-negative lesions. In the PN group, CSF GFAP levels were significantly lower in patients with purely demyelinating neuropathy compared to those with axonal or mixed neuropathy. CONCLUSION:GFAP serves as a sensitive marker for axonal damage in PN, while UCHL-1 closely correlates with disease activity in MS patients.

Despite the abundance of data on the COVID-19 vaccine-induced immune activation, the impact of natural autoantibodies (nAAbs) on these processes is less well defined. Therefore, we investigated potential connections between vaccine efficacy and nAAb levels. We were also interested in the impact of immunomodulatory therapies on vaccine efficacy. Clinical residual samples were used for the assessment of the COVID-19 vaccine-elicited immune response (IR) (n=255), as well as for the investigation of the immunization-associated expansion of the nAAb pool (n=185). In order to study the potential interaction between immunomodulatory therapies and the vaccine-induced IR, untreated, healthy individuals and patients receiving anti-TNFα or anti-IL-17 therapies were compared (n total =45). In-house ELISAs (anticitrate synthase, anti-HSP60 and-70) and commercial ELISAs (anti-SARS-CoV-2 ELISAs IgG, IgA, NeutraLISA and IFN-γ release assay ‘IGRA’) were applied. We found significant differences in the IR given to different vaccines. Moreover, nAAb levels showed plasticity in response to anti-COVID-19 immunization. We conclude that our findings may support the theorem about the non-specific beneficial ‘side effects’ of vaccination, including the broadening of the nAAb repertoire. Considering immunomodulation, we suggest that anti-TNFα and anti-IL17 treatments may interfere negatively with MALT-associated IR, manifested as decreased IgA titers; however, the modest sample numbers of the herein presented model might be a limiting factor of reaching a more comprehensive conclusion.