Nasal endothelial interleukin-10 expression is negatively correlated with nasal symptoms after allergen provocation

Study on the Mechanism of Allergic Rhinitis Based on the Expression of FIB, PCT, hs-CRP, and Th17/Treg-IL10/IL-17 Axis Balance

BACKGROUND

The pathogenesis of allergic rhinitis (AR) is ambiguous, while it is clear that various immune cells and cytokines play crucial roles in its occurrence and development.

AIM

To investigate the effect of exogenous interleukin-10 (IL-10) on the expression of fibrinogen (FIB), procalcitonin (PCT), hypersensitive C-reactive protein (hs-CRP), and Th17/Treg-IL10/IL-17 axis balance in the nasal mucosa of rats with AR.

METHOD

In this study, 48 female-specific pathogen-free Sprague-Dawley rats were randomly divided into 3 groups: blank control group, AR group, and IL-10 intervention group. The AR model was established in the AR group and IL-10 group. The rats in the control group were treated with normal saline; the rats in the AR group were given 20 μL of saline containing 50 μg of ovalbumin (OVA) every day. The rats in the IL-10 intervention group were intraperitoneally injected with 1 mL of 40 pg/kg IL-10 and provided with OVA. The IL-10 intervention group was composed of mice with AR that received IL-10. The behavior of nasal allergic symptoms (such as nasal itching, sneezing, and runny nose) and the hematoxylin and eosin staining of nasal mucosa were observed. The levels of FIB, PCT, hs-CRP, IgE, and OVA sIgE in serum were determined by enzyme-linked immunosorbent assay. The levels of Treg and Th17 cells in serum were detected by flow cytometry. The protein levels of TGF-β, IL-10, and IL-17 in nasal mucosa were detected by the Western-blot method.

RESULTS

The scores of snots, nasal itching, and sneezing in the AR group were significantly higher than those in the control group, while the scores of the above symptoms in the IL-10 intervention group were lower than those in the AR group. The levels of FIB, PCT, hs-CRP, IgE, and OVA sIgE in serum and the protein levels of IL-10 and IL-17 in the nasal mucosa in the AR group were higher than those in the blank control group. Meanwhile, the levels of FIB, PCT, hs-CRP, IgE, and OVA sIgE in serum and IL-10 and IL-17 protein in the nasal mucosa in the IL-10 group were lower than those in the AR group.

CONCLUSION

IL-10 can relieve the allergy of AR rats by affecting the expression of FIB, PCT, and hs-CRP, as well as the balance of the Th17/Treg-IL10/IL-17 axis in the nasal mucosa of AR rats.

IL-10 Has Differential Effects on the Innate and Adaptive Immune Systems of Septic Patients

Sepsis, a disease of divergent pro- and anti-inflammatory-mediated pathways, has a high prevalence of morbidity and mortality, yet an understanding of potential unifying mediators between these pathways that may improve clinical outcomes is largely unclear. IL-10 has classically been designated an immunosuppressive cytokine, although recent data suggest that under certain conditions IL-10 can be immune stimulatory. We sought to further investigate the effect of IL-10 on innate and adaptive immunity in an in vitro human observational cohort study in patients with sepsis via modulation of IL-10 on IFN-γ production by T cells and TNF-α production and HLA-DR expression by monocytes. These results were compared with critically ill nonseptic patients and healthy volunteers. ELISpot analysis was performed using PBMC fraction from patient whole-blood samples. Finally, to provide additional potential clinical relevance, we examined the effect of IL-10 on T cell IFN-γ production in an in vivo cecal ligation and puncture model of sepsis using C57 black/J6 female mice. We found that inhibition of IL-10 significantly increased both production of T cell IFN-γ and monocyte TNF-α, whereas addition of IL-10 increased T cell IFN-γ production but decreased monocyte production of TNF-α and HLA-DR expression. There was no significant effect of IL-10 on control cohorts. IL-10-treated septic mice demonstrated increased IFN-γ production in splenocytes. Thus, IL-10 demonstrates both pro- and anti-inflammatory effects in the septic microenvironment, which is likely cell and context dependent. Further elucidation of relevant signaling pathways may direct future therapeutic targets.

Regulatory effect of TLR3 signaling on staphylococcal enterotoxin-induced IL-5, IL-13, IL-17A and IFN-γ production in chronic rhinosinusitis with nasal polyps

BACKGROUND

Toll-like receptor 3 (TLR3) is expressed in upper airways, however, little is known regarding whether Toll-like receptor 3 (TLR3) signals exert a regulatory effect on the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP), especially on eosinophilic inflammation. We sought to investigate the effect of Poly(IC), the ligand for TLR3, on cytokine production by dispersed nasal polyp cells (DNPCs).

METHODS

DNPCs were pretreated with or without Poly(IC), and were then cultured in the presence or absence of staphylococcal enterotoxin B (SEB), following which the levels of IL-5, IL-10, IL-13, IL-17A and interferon (IFN)-γ in the supernatant were measured. To determine the involvement of IL-10 and cyclooxygenase in Poly(IC)-mediated signaling, DNPCs were treated with anti-IL-10 monoclonal antibody and diclofenac, the cyclooxygenase inhibitor, respectively. Poly(IC)-induced prostaglandin E2 (PGE2) production was also determined.

RESULTS

Exposure to Poly(IC) induced a significant production of IL-10, but not of IL-5, IL-13, IL-17A or IFN-γ by DNPCs. Pretreatment with Poly(IC) dose-dependently inhibited SEB-induced IL-5, IL-13 and IL-17A, but not IFN-γ production. Neutralization of IL-10 significantly abrogated the inhibitory effect of Poly(IC). Treatment with diclofenac also abrogated the inhibitory effect of Poly(IC) on SEB-induced IL-5 and IL-13 production. However, unlike exposure of diclofenac-treated DNPCs to lipopolysaccharide, the ligand for TLR4, exposure of these cells to Poly(IC) did not enhance IL-5 or IL-13 production. Poly(IC) did not significantly increase PGE2 production by DNPCs.

CONCLUSIONS

These results suggest that TLR3 signaling regulates eosinophilia-associated cytokine production in CRSwNP, at least in part, via IL-10 production.

Immunomodulation and Disease Tolerance to Staphylococcus aureus

The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and disease tolerance mechanisms that promote commensalism to S. aureus.

The effectiveness of acupuncture compared to loratadine in patients allergic to house dust mites

Background. The aim of this work was to evaluate the clinical effectiveness of acupuncture and its impact on the immune system in comparison to loratadine in the treatment of persistent allergic rhinitis caused by house dust mites. Methods. In this study, 24 patients suffering from persistent allergic rhinitis induced by house dust mites were treated either with acupuncture (n = 15) or with loratadine (n = 9). The evaluation of the data was based on the subjective and the objective rhinoconjunctivitis symptom scores, specific and total IgE, and interleukins (IL-4, IL-10, and IFN- γ ) as markers for the activity of Th1 or Th2 cells. Results. The treatments with acupuncture as well as with loratadine were considered effective in the patients' subjective assessment, whereby the effect of the acupuncture tended to be assessed as more persistent after the end of treatment. A change in the specific or the total IgE was not detectable in either group. The interleukin profile showed the tendency of an increasing IL-10 value in the acupuncture group. The results of the study show that the effectiveness of acupuncture is comparable to that of loratadine. Conclusion. Acupuncture is a clinically effective form of therapy in the treatment of patients suffering from persistent allergic rhinitis. The results indicate the probability of an immunomodulatory effect.

Exogenous interleukin-10 alleviates allergic inflammation but inhibits local interleukin-10 expression in a mouse allergic rhinitis model

Background

Interleukin-10 (IL-10) has an important anti-inflammatory and immunoregulatory function, and its expression is negatively correlated with the development and severity of allergic rhinitis (AR). However, the in vivo effects of exogenous IL-10 on AR have not been studied and the mechanisms underlying the effects of IL-10 have not been fully understood. Here, we investigated the effects of intranasal administration of recombinant mouse (rm) IL-10 on the expression of Th responses and local IL-10 in a mouse model of AR induced by ovalbumin.

Results

Administration of rmIL-10 during challenge significantly reduced the number of eosinophils and mast cells, as well as Type 2 helper T (Th2) and Th17 cell related cytokine and transcription factor levels in the nasal mucosa and nasal lavage fluid in AR mice. The rmIL-10 treatment significantly inhibited the number of IL-10-positive cells and IL-10 mRNA expression in the nasal mucosa in AR mice.

Conclusion

Our results show that exogenous IL-10 administrated in challenge phase alleviates nasal allergic inflammation in AR mice, most likely by inhibiting Th2 and Th17 responses. It can also inhibit local IL-10 levels in the nasal mucosa. Our findings indicate that IL-10 may have the potential as an inhibitor of AR.

Characterisation of interleukin-10 expression on different vascular structures in allergic nasal mucosa

BACKGROUND

Interleukin-10 (IL-10) is a negative regulator of immune responses and was previously shown to be expressed by human nasal endothelial cells, while the adhesion molecule MECA-79 plays a role in trans-endothelial migration of immune competent cells. In this study we investigate the relationship between endothelial IL-10 and MECA-79 expression to address the question whether immune competent cells could be affected at the mucosal entry site.

METHODS

Nasal turbinate biopsies were taken from house dust mite allergic patients, before and after nasal allergen provocation. Subsequent slides of biopsies were stained for IL10, MECA-79, CD34, and IL10-Receptor. Capillaries, arteries/veins, and sinusoids were evaluated separately.

RESULTS

90% of sinusoids are IL-10 positive and all sinusoids are negative for MECA-79, while 4.8% of capillaries are positive for IL-10, and 2.2% are positive for MECA-79. Although about 47% of arteries/veins are positive for IL-10 and 57.1% are positive for MECA-79, only about 20% are positive for both markers. Furthermore, we showed that the myo-fibroblasts surrounding all sinusoids stain positive for IL10R.

CONCLUSIONS

IL10 expression on vascular structures is not related to MECA expression for sinusoids and capillaries and only partly related on arteries/veins, however sinusoidal endothelial IL10 expression is always seen in combination with IL-10R expression of sinusoidal myo-fibroblasts.

Conjunctival provocation with airborne allergen in patients with atopic keratoconjunctivitis

BACKGROUND

Atopic keratoconjunctivitis (AKC) is a chronic eye disease with periods of exacerbations. Many patients experience no obvious seasonal variation, although a majority of patients are allergic to common airborne allergens.

OBJECTIVE

To investigate the allergic reaction, to conjunctival provocation with airborne allergens, in patients with AKC.

METHODS

Eleven patients with AKC and birch and/or grass pollen allergy participated in the study, which was performed outside the pollen season. Five patients with seasonal allergic conjunctivitis (SAC) and five healthy subjects were included for validation purposes. The challenge was performed in one eye with the allergen, to which the patient was reactive, and with dilution buffer in the other eye. Signs and symptoms from both eyes were graded at baseline and at 10 min, 8 and 48 h after provocation. Tear fluid was collected from both eyes for cytokine analyses at baseline and at 8 and 48 h.

RESULTS

A significant change in clinical symptoms and signs, (redness and chemosis) was evident 10 min after provocation compared with baseline (P = 0.005) and compared with the unprovoked eye (P = 0.005) in AKC subjects. These parameters were normalized after 8 and 48 h. A significant increase for IFN-γ (P = 0.021) and IL-6 (P = 0.015), and a near significant increase for IL-10 (P = 0.066) were seen in the tear fluid of the challenged eye at 48 h after provocation vs. baseline and vs. the control eye for IFN-γ (P = 0.005), IL-6 (P = 0.028) and IL-10 (P = 0.008) in AKC subjects.

CONCLUSION AND CLINICAL RELEVANCE

In this single dose allergen provocation study, AKC patients responded with a typical IgE-mediated allergic reaction. An increase in cytokines at 48 h after the challenge was demonstrated and might, with further studies, give us a better understanding of the nature of inflammation in AKC.