Low Expression of IL-10 in Circulating Bregs and Inverted IL-10/TNF-α Ratio in Tears of Patients with Perennial Allergic Conjunctivitis: A Preliminary Study

Vitamin D and tear fluid cytokines in predicting outcomes in viral conjunctivitis - A new outlook

PURPOSE

To determine the association between systemic vitamin D (VD) and immunoglobulin E (IgE) levels with severity and ocular surface inflammatory profile in patients with epidemic keratoconjunctivitis (EKC).

METHODS

210 eyes of 105 patients who were clinically diagnosed with EKC were included in the study. The levels of serum VD and serum IgE were measured. Schirmer's strip-based tear fluid (TF) was used to determine levels of IL-1β, IL-6, IL-10, IL-17A, TNFα, MMP9, sICAM1, and VEGF-A in a subset of patients.

RESULTS

Levels of VD were significantly ( P < 0.05) lower and levels of IgE were significantly higher in patients with severe forms of conjunctivitis compared to those with nonsevere forms. Majority of the patients with severe forms of the disease exhibited VD deficiency and/or abnormally high IgE. A negative correlation (r = -0.682; P < 0.0001) was observed between VD and IgE levels. TF levels of IL-1β, IL-6, TNFα, and sICAM1 were significantly higher in eyes with severe forms of conjunctivitis compared to those with nonsevere forms and controls. These factors showed a positive correlation ( P < 0.05) with IgE levels and a negative correlation ( P < 0.05) with VD levels.

CONCLUSION

Patients with severe forms of EKC exhibited VD deficiency and higher levels of IgE. Increased TF inflammatory factors demonstrated a disease causal relationship with VD and IgE. Hence, restoring the altered levels of VD and IgE to normal range would be pivotal in the prevention and management of severe conjunctivitis.

Consolidating data on the association of IL-6 and IL-10 polymorphisms with the development of glaucoma: a meta-analysis

BACKGROUND

The study aimed to investigate the association of IL-6 and IL-10 polymorphisms with susceptibility to glaucoma by analyzing all relevant individual studies.

MATERIALS AND METHODS

Relevant articles were gathered from PubMed, Web of Science, Embase, WanFang, and CNKI databases up to 15 October 2023. Odds ratios (ORs) were used to evaluate the association strengths, along with 95% confidence intervals (CIs).

RESULTS

Seven case-control studies involving 1408 cases and 1789 controls on the IL-6 -174 G>C polymorphism, and three studies with 675 cases and 1100 controls on the IL-6 -572 G>C were included. Moreover, three separate studies, each comprising 442 cases and 672 controls, investigated the IL-10 -592C>A, -819T>C, and -1082A>G polymorphisms. The combined data indicated a significant association between -592C>A, -819T>C, and -1082A>G at IL-10 gene and IL-6 -572 G>C with glaucoma susceptibility, with no correlation found for IL-6 -174 G>C.

CONCLUSIONS

The study found that IL-10 -592C>A, -819T>C, -1082A>G, and IL-6 -572 G>C polymorphisms were linked to glaucoma risk. However, no significant association was observed for IL-6 -174 G>C. These findings imply a possible connection between genetic variations in these genes and glaucoma risk. Further research is crucial to fully understand the underlying mechanisms and their significance in managing and preventing glaucoma.

TNF is a critical cytokine in age-related dry eye disease

Aging is a complex biological process that is characterized by low-grade inflammation, called inflammaging. Aging affects multiple organs including eye and lacrimal gland. Tumor necrosis factor (TNF) is a pleiotropic cytokine that participates in inflammation, activation of proteases such as cathepsin S, and formation of ectopic lymphoid organs. Using genetic and pharmacological approaches, we investigated the role of TNF in age-related dry eye disease, emphasizing the ocular surface and lacrimal gland inflammation. Our results show the increased protein and mRNA levels of TNF in aged lacrimal glands, accompanied by increased TNF, IL1β, IL-18, CCL5, CXCL1, IL-2, IL-2 receptor alpha (CD25), IFN-γ, IL-12p40, IL-17, and IL-10 proteins in tears of aged mice. Moreover, genetic loss of the Tnf-/- in mice decreased goblet cell loss and the development of ectopic lymphoid structures in the lacrimal gland compared to wild-type mice. This was accompanied by a decrease in cytokine production. Treatment of mice at an early stage of aging (12-14-month-old) with TNF inhibitor tanfanercept eye drops for eight consecutive weeks decreased cytokine levels in tears, improved goblet cell density, and decreased the marginal zone B cell frequency in the lacrimal gland compared to vehicle-treated animals. Our studies indicate that modulation of TNF during aging could be a novel strategy for age-related dry eye disease.

The correlation between tic disorders and allergic conditions in children: A systematic review and meta-analysis of observational studies

Aim

To evaluate the correlation between tic disorders and allergies and to inform strategies for the treatment and prevention of tic disorders.

Methods

We conducted online searches of the MEDLINE, Embase, Cochrane, CNKI, CBM, WanFang, and VIP Information databases. Case-control studies and cohort studies related to tic disorders and allergic conditions were searched. Two researchers screened the literature, extracted data, and evaluated quality in strict accordance with the predetermined retrieval strategy and inclusion criteria. Finally, RevMan 5.4 software was used to conduct a meta-analysis. We used the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach to rating the certainty of evidence about each allergy outcome as high, moderate, low, or very low.

Results

We obtained seven eligible studies involving eight allergic conditions. The following allergic conditions were significantly associated with the presence of a tic disorder: asthma (OR = 1.90, 95% CI = 1.57-2.30, P < 0.001), allergic rhinitis (OR = 2.61, 95% CI = 1.90-3.57, P < 0.001), allergic conjunctivitis (OR = 3.65, 95% CI = 1.53-8,67, P = 0.003), eczema (OR = 3.87, 95% CI = 2.24-6.67, P < 0.001) and food allergy (OR = 2.79, 95% CI = 1.56-4.99, P < 0.001). There was no significant correlation between atopic dermatitis, urticaria, drug allergy, and tic disorder.

Conclusion

The occurrence of tic disorders may be associated with the presence of certain allergic disorders. However, whether allergy is one of the causes of tic disorders remains unclear.

Systematic review registration

The registration number for this systematic review is PROSPERO: CRD42021231658.

Increased Expression of TLR4 in Circulating CD4+T Cells in Patients with Allergic Conjunctivitis and In Vitro Attenuation of Th2 Inflammatory Response by Alpha-MSH

Ocular allergic diseases are frequently seen in ophthalmological clinical practice. Immunological damage is mediated by a local Th2 inflammatory microenvironment, accompanied by changes in circulating cell subsets, with more effector cells and fewer T regulatory cells (Tregs). This study aimed to evaluate the involvement of toll-like receptor 4 (TLR4) and α-melanocyte stimulating hormone (α-MSH) in the immune regulation associated with perennial allergic conjunctivitis (PAC). We performed an Ag-specific stimulation during 72 h of culturing with or without lipopolysaccharide (LPS) or α-MSH in peripheral blood mononuclear cells (PBMC), analyzing the cell subsets and cytokines induced by the stimuli. We also determined α-MSH in tear samples from healthy donors (HD) or PAC patients. Our findings demonstrate an immunological dysregulation characterized by an increased frequency of CD4+TLR4+ in the PBMC of patients with PAC, compared to HD. Most of these CD4+TLR4+ cells were also CD25+, and when α-MSH was added to the culture, the percentage of CD4+CD25+FoxP3+ increased significantly, while the percentage of CD69+ cells and cytokines IL-4 and IL-6 were significantly decreased. In tears, we found an increased concentration of α-MSH in PAC patients, compared with HD. These findings indicate a novel mechanism involved in controlling ocular allergic diseases, in which α-MSH diminishes the concentration of IL-6 and IL-4, restoring the frequency of Tregs and down-regulating CD4 activation. Moreover, we demonstrated the involvement of CD4+TLR4+ cells as an effector cell subset in ocular allergy.

Activation of IL-10+ B cells: A novel immunomodulatory mechanism for therapeutic bacterial suspensions

Objectives:

Bacterial components are used to improve immune responses in patients with respiratory infections. Pharmacological formulations of bacterial components include a mixture of bacterial antigens, some of which are complete inactivated bacteria, that is, named bacterial suspensions; while others are fragments of bacteria, which are presented as bacterial lysates. Although bacterial lysates have been broadly used as immune-stimulators, the biological support for the therapeutic effectiveness of bacterial suspension has not yet been studied. Thus, the aim of our study was to investigate the immunological activity induced by bacterial suspension.

Methods:

This work was an exploratory translational study. Peripheral blood mononuclear cells were obtained from healthy donors and cultured in time–dose dependent assays with a commercial bacterial suspension. Flow cytometry was used for phenotypic analysis and for determining soluble cytokines in culture supernatants.

Results:

We observed that bacterial suspension activates B cells in a dose-dependent manner. Peripheral blood mononuclear cells were able to secrete IL-6 and IL-10 after 24 h of bacterial suspension stimulation. TLR2 expression was observed mainly on CD19+ CD38^Lo B cells after 72 h of culture; remarkably, most of the TLR2+ CD19+ cells were also IL-10+.

Conclusion:

Our findings suggest that bacterial suspension induces the activation of B cell subsets as well as the secretion of IL-6 and IL-10. Expression of TLR2 on CD19+ cells could act as an activation loop of IL-10+ B regulatory cells. The clinical implications of these findings are discussed at the end of this article.