Molecular Hydrogen as a Promising Therapy Could Be Linked With Increased Resting Treg Cells or Decreased Fas+ T Cell Subsets in a IgG4-PF-ILD Patient: A Case Report.

BACKGROUND/AIM: Progressive fibrosing interstitial lung disease (PF-ILD) refers to a group of chronic lung conditions commonly associated with immunoglobulin G4-related disorders. It is characterized by progressive scarring (fibrosis) within the pulmonary interstitium, resulting in respiratory failure and early mortality. Some patients do not respond to standard therapeutic interventions. Numerous studies have confirmed the anti-inflammatory and antioxidant properties of molecular hydrogen in various disease models. CASE REPORT: In this report, we present a case study of an 85-year-old female diagnosed with suspected IgG4-related PF-ILD complicated by hospital-acquired pneumonia. On the fourth day of hydrogen-assisted therapy, a noticeable improvement in lung infiltrations was observed in chest X-rays as the patient gradually progressed towards weaning off mechanical ventilation. To assess treatment responses, we compared immune phenotypes before and after hydrogen treatment. A marked increase was observed in resting regulatory T cell levels after treatment, accompanied by a notable decrease in Fas+ helper T cell and cytotoxic T cell subtypes. CONCLUSION: This case study highlights the effectiveness of hydrogen-assisted therapy in managing PF-ILD complicated by pneumonia, warranting further research in the future.

IVIG as a Promising Therapy for Methotrexate-induced Life-threatening Neutropenic Enterocolitis in an Elderly Patient With Rheumatoid Arthritis: A Case Report and Literature Review.

BACKGROUND/AIM: Rheumatoid arthritis (RA) is a chronic autoimmune disease associated with the functional impairment of multiple joints and the destruction of bone and cartilage. Methotrexate (MTX) is a first-line drug commonly used to treat RA; however, even low doses of MTX can potentially cause rare but severe adverse reactions, such as neutropenic enterocolitis (NE), a life-threatening disease characterized by intestinal mucosal damage and immunodeficiency. CASE REPORT: Here, we report on an 82-year-old RA patient who developed life-threatening NE after ten years of low-dose MTX treatment. The condition of the patient rapidly worsened, requiring emergency electrical cardioversion and intravenous treatment with immunoglobulin (IVIG). Immunophenotypic responses were analyzed before and after treatment to evaluate therapeutic efficacy. CONCLUSION: This case highlights the importance of monitoring elderly patients with RA receiving low-dose MTX treatment for the potential accumulation of MTX toxicity. Our findings also illustrate the importance of providing timely IVIG therapy for MTX-induced NE.

Functional implications of rs9373441 with FOXP3+Treg and Tr1 for the clinical effectiveness of csDMARDs in rheumatoid arthritis.

Rheumatoid arthritis (RA) is characterized by a deficiency in regulatory T cells (Treg), which play a crucial role in immune regulation. While conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) are widely used, there remains a challenge as efficacy varies among patients. In this genome-wide association study (GWAS) involving 410 RA patients, rs9373441 emerged as the most significantly linked single-nucleotide polymorphism (SNP) to csDMARDs response. This non-coding variant functions as a cis-acting regulatory element within the UTRN gene, which is associated with cortical erosion and osteoporosis. Particularly, individuals with the TT allele at rs9373441 exhibited a more favorable response, characterized by a significant increase in FOXP3 + Treg and Type 1 regulatory T cells (Tr1) (p = 0.04, 0.02) and a decrease in Effector T helper cells (Effector Th) (p = 0.03). The GATA3-GCM2-PTH and GATA3-FOXO1-FOXP3 pathways were implicated. RNA-sequencing (RNA-seq) analysis revealed increased expression levels of UTRN, PTH2R, FOXO1, and FOXO3 in good and moderate responders (p = 0.01, 0.03, 0.0005, and 0.02). Notably, the change in FOXP3 + Treg and Tr1 was positively correlated with UTRN expression (both p = 0.03). These findings underscore the critical link between rs9373441 and the response to csDMARDs, empowering clinicians to tailor treatments for enhanced outcomes in patients with RA.

Using Treg, Tr1, and Breg Expression Levels to Predict Clinical Responses to csDMARD Treatment in Drug-naive Patients With Rheumatoid Arthritis.

BACKGROUND/AIM: Regulatory T cells (Treg) play a crucial role in maintaining immune tolerance and preventing autoimmune diseases. Recent data also indicate that type 1 regulatory T (Tr1) and regulatory B (Breg) cells play an inhibitory (i.e., protective) role in autoimmune diseases. Conventional synthetic disease-modifying antirheumatic drugs (csDMARD) are a first-line therapy for rheumatoid arthritis (RA), and our aim was to predict clinical responses of this treatment using immunophenotyping. MATERIALS AND METHODS: We first detected the presence of immune cells in fresh blood from 16 healthy controls (HC) and 26 patients with RA (14 drug-naive and 12 csDMARD-experienced). Then, we recorded immunophenotypic changes in 14 drug-naive RA (naive RA) patients prior to csDMARD treatment (i.e., day 0) and after receiving treatment for 6 months. The observed changes were also compared with other clinical indicators, including the presence of anti-citrullinated peptide antibodies (anti-CCP), rheumatoid factor (RF) levels, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels. RESULTS: Naive RA patients had significantly lower Tregs than HC and csDMARD-experienced patients (both p<0.0001) and the number of Tregs correlated with the diagnosis of RA and therapeutic efficacy of csDMARD treatment. Furthermore, lower baseline levels of Treg, memory Treg, Tr1, and higher PD-1+ Marginal B, Breg cells were significantly associated with decreased development of the 28-joint Disease Activity Score (DAS28) (all p<0.05), revealing better medical response. Multiple regression and principal component analysis identified Treg, Tr1, and Breg as potential predictors of csDMARD responses (Area under curve: 0.9; Accuracy: 92.86%). Furthermore, elevated Treg, Tr1, and Breg cells were associated with decreased DAS28, ESR, and CRP (all p<0.05); changes in Treg and Breg cell expression were also more pronounced among double negative anti-CCP and RF in RA patients with better outcomes (p<0.05). CONCLUSION: Immunophenotyping can be an adjunct clinical tool to identify patients who are poor candidates for csDMARD therapy. Alternative therapeutic interventions in the early stages of disease should be formulated for these patients.

Predicting the clinical efficacy of JAK inhibitor treatment for patients with rheumatoid arthritis based on Fas+ T cell subsets.

Rheumatoid arthritis (RA) is a common autoimmune disease. Janus kinase inhibitors (JAKi) have been approved for the treatment of RA; however, the impact of JAKi on immune cells remains inconclusive. This study investigated the response of immune cells to JAKi treatment to identify biomarkers by which to evaluate and predict clinical outcomes. Blood samples were collected from RA patients before and after JAKi treatment for the analysis of immunophenotypes. Our results revealed that JAKi mainly inhibited Fas+ T cell subsets. The percentage changes of Th Fas+ and Naive Th Fas+ cells were positively correlated with the 28-joint Disease Activity Score with erythrocyte sedimentation rate (DAS28-ESR) values. Following treatment, moderate response (MR) RA patients presented a decrease in the number of Naive Th Fas+ cells (p = 0.0001). Initial percentages of 14 T cell and 20 B cell subsets were correlated with percentage changes in DAS28-ESR. Overall, 16 cell subsets presented significant differences between the non-response (NR) and MR groups. Excluding the multicollinearity of the immune cells, we constructed a JAKi treatment response prediction index (JRPI) using 5 subsets of T/B cells, the results of which were strongly correlated with percentage changes in DAS28-ESR (receiver operating characteristic curve of 1). Note that the NR group was clearly distinguished from the MR group (p = 0.0167). In conclusion, the efficacy of JAKi can be attributed mainly to the suppression of Fas+ T cell subsets. A positive correlation was shown between the therapeutic efficacy of JAKi and the percentage changes in both Th Fas+ cells and Naive Th Fas+ cells. Furthermore, the proposed JRPI could potentially be used as an indicator to predict the efficacy of JAKi prior to treatment in RA patients. These findings may contribute to the development of personalized treatment strategies for RA patients using JAKi.