Increased susceptibility to pneumonia due to tumour necrosis factor inhibition and prospective immune system rescue via immunotherapy

Pediatric infections in the first year of life following maternal biologic exposure for autoimmune disorder treatment: A systematic review

Pregnancy induces immunologic and physiologic changes that can alter disease activity for women with autoimmune disorders (AD), and if exacerbated, may necessitate treatment. Biologics are increasingly prescribed due to their targeted effects, but transplacental transfer to the fetus may increase potential risks to the infant. This review examines the risk of infection and respiratory distress in the first year of life among infants born to women with AD using biologics during pregnancy versus infants exposed to standard therapies. We systematically searched five databases from January 2012 to June 2023. Inclusion was restricted to cohort and case-control studies including infants born to women with rheumatoid arthritis, multiple sclerosis, or systemic lupus erythematosus prescribed a biologic or standard therapy during pregnancy. Quality assessment was performed using the ROBINS-I tool for observational studies. Due to between-study heterogeneity in effect estimates and outcomes, studies were not pooled. Of 2975 identified citations, 10 studies were included. In three studies examining the risk of infant infection, findings were inconsistent largely due to lack of precision (OR range: 0.6-1.4, 95% CI range: 0.2-2.8). For respiratory distress, two studies reported an increased risk among infants exposed to biologics (HR 1.30, 95% CI 1.03,1.74 and RR 1.52, 95% CI 1.06, 2.18) while one did not. Most studies (80%) had a moderate risk of bias. The findings suggest conflicting results for the risk of infant infection and possible associations with respiratory distress. Given the limited number of studies, additional studies are needed to inform treatment decisions for AD during pregnancy.

Role of Tumor Necrosis Factor in Tuberculosis

Tumor necrosis factor (TNF) is a key immunoregulatory cytokine with a dual role in the host response to Mycobacterium tuberculosis. While essential for granuloma formation, macrophage activation, and containment of latent infection, TNF can also contribute to tissue damage and immune pathology. This review systematically analyzes over 300 peer-reviewed studies published between 1980 and 2024, highlighting the molecular and cellular mechanisms of TNF action in tuberculosis (TB). Particular attention is given to TNF receptor signaling pathways, the balance between protective and pathological immune responses, and the modulation of TNF activity during anti-TNF therapy in patients with autoimmune diseases. We discuss how different TNF inhibitors vary in their capacity to interfere with host defense mechanisms, with monoclonal antibodies carrying a higher reactivation risk than receptor-based agents. To enhance conceptual clarity, we provide newly developed schematic representations that integrate current knowledge on TNF-driven immune dynamics, including its interaction with other cytokines, effects on granuloma stability, and role in intracellular bacterial control. Understanding the pleiotropic functions of TNF in tuberculosis pathogenesis is crucial for developing safe immunomodulatory strategies and optimizing the clinical management of patients at risk of latent TB reactivation.

Can pyridoxine function as an anti-pyroptosis agent? A narrative review

BACKGROUND

Pyroptosis, a highly inflammatory form of programmed cell death, plays a key role in diseases such as sepsis, rheumatoid arthritis, Alzheimer's disease, and COPD. It is driven by inflammasome activation, leading to the release of pro-inflammatory cytokines. Pyridoxine (Vitamin B6), an essential micronutrient with known anti-inflammatory effects, has been suggested as a potential regulator of inflammasome activation and pyroptosis. This review examines current evidence on pyridoxine's role in modulating pyroptosis.

METHODS

A literature search was conducted in PubMed, Scopus, and Web of Science for studies published between 2014 and 2024. The search focused on pyridoxine's relationship with inflammation, inflammasomes, and pyroptosis pathways using keywords such as "pyridoxine," "Vitamin B6," "pyroptosis," "inflammasome," "caspase-1," and "gasdermin D." Both preclinical and human studies were reviewed, with emphasis on molecular mechanisms underlying pyridoxine's anti-inflammatory effects.

RESULTS

Studies consistently showed that pyridoxine reduced inflammasome activation, decreased pro-inflammatory cytokine production, and inhibited caspase-1 (CASP-1) activity, thereby suppressing pyroptosis. Human studies, though indirect, linked higher pyridoxine levels to reduced systemic inflammation, suggesting a possible anti-pyroptotic effect.

CONCLUSIONS

Pyridoxine shows potential as an anti-pyroptotic agent due to its anti-inflammatory and immunomodulatory properties. However, further well-designed clinical trials are needed to confirm its role in controlling pyroptosis, especially in diseases associated with excessive inflammasome activation.

Nonlinear Dynamics of TNFR1 and TNFR2 Expression on Immune Cells: Genetic and Age-Related Aspects of Inflamm-Aging Mechanisms

Introduction: Immunosenescence alters TNF receptor expression (TNFR1 and TNFR2), contributing to chronic inflammation (inflamm-aging) and age-related diseases. Polymorphisms in TNFRSF1A and TNFRSF1B may influence receptor expression; however, their role in age-dependent modulation remains unclear. This study examines TNFR1/TNFR2 expression dynamics on T cells, B cells, and monocytes across different ages and evaluates the impact of genetic polymorphisms. Methods: PBMCs from 150 donors (18-60 years) were isolated via density-gradient centrifugation and cultured under spontaneous and LPS-stimulated conditions. TNFR1 and TNFR2 expression on immune cell subsets was quantified using flow cytometry with BD QuantiBRITE PE beads. SNP genotyping in TNFRSF1A and TNFRSF1B was performed via PCR with restriction analysis. Nonlinear age-related trends were assessed using polynomial approximation and inflection point analysis (Tukey's method). Results: Among the 23 analyzed TNF system parameters, the proportion of TNFR2+CD3+ T cells increased with age, whereas TNFR1+ and TNFR2+ monocyte populations showed significant negative correlations (p < 0.05). Inflection points (~27, 34-36, and 44-45 years) indicated nonlinear dynamics in TNFRs expression during aging. TNFR2 expression on T cells gradually increased and stabilized at later ages, whereas TNFR1 and TNFR2 expression on monocytes followed distinct declining trajectories. Genetic polymorphisms influenced correlation strength, but did not alter direction, demonstrating a conserved pattern of age-related receptor expression shifts. Conclusions: TNFR expression exhibits nonlinear, age-dependent alterations across immune cells, shaped by immunosenescence and genetic variability. The identified critical age intervals represent key phases of immune remodeling, where assessing TNFR expression may provide insights into inflamm-aging mechanisms and potential targets for immune modulation.

Vascular inflammaging: Endothelial CEACAM1 expression is upregulated by TNF-α via independent activation of NF-κB and β-catenin signaling

Chronic inflammation with progressive age, called inflammaging, contributes to the pathogenesis of cardiovascular diseases. Previously, we have shown increased vascular expression of the Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) in aged mice and humans, presumably via mutual upregulation with the pro-inflammatory cytokine TNF-α. CEACAM1 is critical for aging-associated vascular alterations like endothelial dysfunction, fibrosis, oxidative stress, and sustained inflammation and can be regarded as a main contributor to vascular inflammaging. This study was conducted to elucidate the mechanisms underlying endothelial CEACAM1 upregulation by TNF-α in detail. Using wildtype (WT) and TNF-α knockout (Tnf-/-) mice, we confirmed that the aging-related upregulation of endothelial CEACAM1 critically depends on TNF-α. The underlying mechanisms were analyzed in an endothelial cell culture model. TNF-α time-dependently upregulated CEACAM1 in vitro. In pharmacological experiments, we identified an early NF-κB- and a delayed β-catenin-mediated response. Involvement of β-catenin was further substantiated by siRNA-mediated knockdown of the β-catenin-targeted transcription factor TCF4. Both signaling pathways acted independent from each other. Elucidating the delayed response, co-immunoprecipitation analysis revealed release of β-catenin from adherens junctions by TNF-α. Finally, TNF-α activated Akt kinase by increasing its Ser473 phosphorylation. Consequently, Akt kinase facilitated β-catenin signaling by inhibiting its degradation via phosphorylation of GSK3β at Ser9 and by increased phosphorylation of β-catenin at Ser552 that augments its transcriptional activity. Taken together, our study provides novel mechanistic insights into the aging-related, inflammation-mediated endothelial upregulation of CEACAM1. Beyond the pathogenesis of cardiovascular diseases, these findings may be significant to all fields of inflammaging.

Decoy peptides that inhibit TNF signaling by disrupting the TNF homotrimeric oligomer

Tumor necrosis factor (TNF) is a pro-inflammatory cytokine and its functional homotrimeric form interacts with the TNF receptor (TNFR) to activate downstream apoptotic, necroptotic, and inflammatory signaling pathways. Excessive activation of these pathways leads to various inflammatory diseases, which makes TNF a promising therapeutic target. Here, 12-mer peptides were selected from the interface of TNF-TNFR based upon their relative binding energies and were named 'TNF-inhibiting decoys' (TIDs). These decoy peptides inhibited TNF-mediated secretion of cytokines and cell death, as well as activation of downstream signaling effectors. Effective TIDs inhibited TNF signaling by disrupting the formation of TNF's functional homotrimeric form. Among derivatives of TIDs, TID3c showed slightly better efficacy in cell-based assays by disrupting TNF trimer formation. Moreover, TID3c oligomerized TNF to a high molecular weight configuration. In silico modeling and simulations revealed that TID3c and its parent peptide, TID3, form a stable complex with TNF through hydrogen bonds and electrostatic interactions, which makes them the promising lead to develop peptide-based anti-TNF therapeutics.

The relationship between neighborhood economic deprivation and community-acquired pneumonia related admissions in Maryland

Introduction

Community-acquired pneumonia (CAP) is a major health concern in the United States (US), with its incidence, severity, and outcomes influenced by social determinants of health, including socioeconomic status. The impact of neighborhood socioeconomic status, as measured by the Distressed Communities Index (DCI), on CAP-related admissions remains understudied in the literature.

Objective

To determine the independent association between DCI and CAP-related admissions in Maryland.

Methods

We conducted a retrospective study using the Maryland State Inpatient Database (SID) to collate data on CAP-related admissions from January 2018 to December 2020. The study included adults aged 18-85 years. We explored the independent association between community-level economic deprivation based on DCI quintiles and CAP-related admissions, adjusting for significant covariates.

Results

In the study period, 61,467 cases of CAP-related admissions were identified. The patients were predominantly White (49.7%) and female (52.4%), with 48.6% being over 65 years old. A substantive association was found between the DCI and CAP-related admissions. Compared to prosperous neighborhoods, patients living in economically deprived communities had 43% increased odds of CAP-related admissions.

Conclusion

Residents of the poorest neighborhoods in Maryland have the highest risk of CAP-related admissions, emphasizing the need to develop effective public health strategies beneficial to the at-risk patient population.

The Role of Chlamydia pneumoniae in the Aetiology of Autoimmune Diseases

Introduction The most prevalent chronic human autoimmune disorder worldwide is rheumatoid arthritis. Synovial samples from acute-phase patients are polymerase chain reaction-positive for Chlamydia pneumoniae (C. pneumoniae) DNA and express chlamydial hsp60. Furthermore, anti-cyclic citrullinated peptide (anti-CCP) antibodies promote apoptosis of mature human Saos-2 osteoblasts via cell surface binding to citrullinated heat shock protein 60 (HSP60). Hence, we hypothesised that C. pneumoniae infection is associated with anti-CCP antibodies. Methods C. pneumoniae IgA and anti-CCP antibody levels were determined in 26 healthy subjects in this cross-sectional study. Serum C. pneumoniae IgA antibody levels were assessed using an enzyme-linked immunosorbent assay. Serum anti-CCP antibody levels were assessed using fluoroenzymeimmunoassay. Results There was a highly significant positive correlation between the two sets of antibodies (rs = 0.621; P = 0.0007). Linear regression analysis showed that this correlation was not the result of age or sex. Discussion A biologically plausible mechanism is put forward for these results, involving HSP60 acting as an endogenous ligand for toll-like receptor 4 (TLR4) and the interaction of TLR4 with lipopolysaccharides, which occur in the outer membrane of the C. pneumoniae elementary body. Pronounced pro-inflammatory mediator secretion then takes place. The release of Ca2+ ions may then activate local peptidylarginine deiminases, leading to the formation of CCPs and thus the reported finding. Confirmation of these results may have potential clinical implications in terms of diagnosis, including pre-symptomatic diagnosis, and treatment.

Can Biologics Be Discontinued in Patients with Psoriatic Arthritis in Stable Remission? A Prospective Single‐CenterClinical and Ultrasound Study

Biologic disease‐modifying antirheumatic drugs (bDMARDs) and particularly tumor necrosis factor inhibitors (TNFi) have dramatically changed the natural history of psoriatic arthritis (PsA), making complete clinical remission possible in most patients. However, TNFi drugs are not without potential adverse effects such as increased infectious risk. In addition, their extensive use is associated with a significant economic burden. This prospective longitudinal cohort study involving 45 PsA patients treated with TNFi in stable remission aimed to evaluate by both clinical examination and ultrasound timing and predictive factors of disease relapse after discontinuation of TNFi treatment. Thirty‐nine (86.6%) of 45 enrolled patients experienced disease relapse during the follow‐up period, while six patients (13.4%) maintained remission beyond the scheduled 104 weeks. The median survival time of drug‐free remission after TNFi discontinuation was 24 weeks (95% confidence interval (CI): 22.6–25.4). Disease relapse was characterized by marked clinical and ultrasound worsening of dermatologic and rheumatologic conditions. However, resuming previously discontinued treatment allowed all patients to quickly regain clinical remission. Interestingly, axial involvement was a key feature of the symptomatological pattern of disease relapse, being the main reason for treatment restart in 26% of our cohort. Based on a multivariate Cox model, three variables (VAS pain, tender joint count, and swollen joint count) of the clinical assessment performed at the time point of TNFi treatment onset negatively influenced the time to disease relapse. In conclusion, temporary discontinuation of TNFi drugs is feasible and relatively safe. However, as few predictors of the risk and timing of disease relapse have been identified, patients should be closely monitored when therapy is discontinued.