Immunoreactivity profile of peripheral blood mononuclear cells from patients with ragweed-induced allergic rhinitis

Reduced CD4+T Cell CXCR3 Expression in Patients With Allergic Rhinitis

While T cells are considered to play a primary role in IgE-mediated atopic diseases, little is known about the systemic variations of T cell subsets from patients with allergic rhinitis (AR). To elucidate the characteristics of peripheral T cells, we analyzed natural killer, B cell, and T cell populations, performed T cell subset construction, and assessed chemokine receptor and associated serum cytokine expression in 25 AR patients and 20 healthy controls. Our results revealed increased levels of CD4⁺T cells, serum interleukin (IL)-10, IL-6, and interferon (IFN)-γ, and reduced Th1 and Th17 subsets, identified by their chemokine receptors, in AR patients. These results suggest a systemic activation of T cell responses in AR. We further demonstrated that AR patients exhibit significantly reduced CD4⁺T cell CXCR3 expression, especially in patients with moderate-severe disease severity, demonstrating that CXCR3 is a potential key molecule that hinders the Th1/Th2 balance in AR pathology. Overall, systemic T cell activation occurred in AR patients and CXCR3 dramatically decreased in CD4⁺T cells, which may ultimately be used as a potential disease and/or therapeutic target.

Relationship between chemokines and T lymphocytes in the context of respiratory allergies (Review)

Allergic diseases have been classified in the last decades using various theories. The main classes of the newest classification in allergic respiratory diseases focus on the characterization of the endotype (which takes into account biomarkers related to determinant pathophysiological mechanisms) and of the phenotype (based on the description of the disease). Th2, Th1 and Th17 lymphocytes and the type of inflammatory response mediated by them represent the basis for Th2 and non-Th2 endotype classification. In addition, new lymphocytes were also used to characterize allergic diseases: Th9 lymphocytes, Th22 lymphocytes, T follicular helper cells (T_FH) lymphocytes and invariant natural killer T (iNKT) lymphocytes. In the last decade, a growing body of evidence focused on chemokines, chemoattractant cytokines, which seems to have an important contribution to the pathogenesis of this pathology. This review presents the interactions between chemokines and Th lymphocytes in the context of Th2/non-Th2 endotype classification of respiratory allergies.

Soluble CD163 modulates cytokine production by peripheral blood mononuclear cells stimulated by Dermatophagoides pteronyssinus allergens in vitro

PURPOSE

The CD163 is a scavenger receptor expressed exclusively on monocytes/macrophages which has been shown to exert anti-inflammatory effects. The aim of this study was to evaluate the effect of exogenous sCD163 on production of selected cytokines by peripheral blood mononuclear cells (PBMC) of house dust mite allergic patients (AAPs) stimulated in vitro with Dermatophagoides pteronyssinus (Dp) allergens.

PATIENTS AND METHODS

The study was performed in 24 AAPs and 12 healthy control subjects (HCs). Peripheral blood mononuclear cells were cultured for up to 144h (T₁₄₄) in the presence of Dp extract with or without sCD163. Concentration of interleukin (IL) - 10, IL-13 and transforming growth factor beta (TGF-β) was evaluated in the cell culture supernatants using ELISA. Expression of the selected cytokines was evaluated in cell culture lysates using Taqman-based real time polymerase chain reaction (RT-PCR).

RESULTS

Dp-stimulated PBMC from AAPs released more IL-10 and IL-13 than those from HCs. The greatest up-regulation of IL-10 expression was seen at T₆, while that of IL-13 was delayed. Soluble CD163 augmented production of IL-10 in response to Dp stimulation. No significant effect of sCD163 on production of IL-13 and IL-10 by PBMC of HCs could be demonstrated.

CONCLUSIONS

In AAPs sCD163 modulates the immune response to Dp allergens potentiating anti-inflammatory, homeostatic mechanisms.

PLD1 activation mediates Amb a 1-induced Th2-associated cytokine expression via the JNK/ATF-2 pathway in BEAS-2B cells

The purpose of this study was to identify the role of phospholipase D1 (PLD1) in Amb a 1-induced IL-5 and IL-13 expression. When BEAS-2B cells were stimulated with Amb a 1, PLD activity increased, and knockdown of PLD1 decreased Amb a 1-induced IL-5 and IL-13 expression. Amb a 1 also activated the PLCγ/p70S6K/JNK pathway. Furthermore, Amb a 1-induced PLD activation was also attenuated by PLCγ inhibition, and knockdown of PLD1 decreased Amb a 1-induced activation of P70S6K and JNK. When ATF-2 activity was blocked with ATF-2 siRNA, Amb a 1-induced IL-5 and IL-13 expression was completely abolished, indicating that ATF-2 is a transcriptional factor required for the expression of IL-5 and IL-13 in response to Amb a 1. Taken together, we suggest that PLD1 acts as an important regulator in Amb a 1-induced expression of IL-5 and IL-13 via a PLCγ/p70S6K/JNK/ATF-2 pathway in BEAS-2B cells.

Cyclooxygenase-2 inhibits T helper cell type 9 differentiation during allergic lung inflammation via down-regulation of IL-17RB

RATIONALE

Helper CD4(+) T cell subsets, including IL-9- and IL-10-producing T helper cell type 9 (Th9) cells, exist under certain inflammatory conditions. Cyclooxygenase (COX)-1 and COX-2 play important roles in allergic lung inflammation and asthma. It is unknown whether COX-derived eicosanoids regulate Th9 cells during allergic lung inflammation.

OBJECTIVES

To determine the role of COX metabolites in regulating Th9 cell differentiation and function during allergic lung inflammation.

METHODS

COX-1(-/-), COX-2(-/-), and wild-type (WT) mice were studied in an in vivo model of ovalbumin-induced allergic inflammation and an in vitro model of Th9 differentiation using flow cytometry, cytokine assays, confocal microscopy, real-time PCR, and immunoblotting. In addition, the role of specific eicosanoids and their receptors was examined using synthetic prostaglandins (PGs), selective inhibitors, and siRNA knockdown.

MEASUREMENTS AND MAIN RESULTS

Experimental endpoints were not different between COX-1(-/-) and WT mice; however, the percentage of IL-9(+) CD4(+) T cells was increased in lung, bronchoalveolar lavage fluid, lymph nodes, and blood of allergic COX-2(-/-) mice relative to WT. Bronchoalveolar lavage fluid IL-9 and IL-10, serum IL-9, and lung IL-17RB levels were significantly increased in allergic COX-2(-/-) mice or in WT mice treated with COX-2 inhibitors. IL-9, IL-10, and IL-17RB expression in vivo was inhibited by PGD2 and PGE2, which also reduced Th9 cell differentiation of murine and human naive CD4(+) T cells in vitro. Inhibition of protein kinase A significantly increased Th9 cell differentiation of naive CD4(+) T cells isolated from WT mice in vitro.

CONCLUSIONS

COX-2-derived PGD2 and PGE2 regulate Th9 cell differentiation by suppressing IL-17RB expression via a protein kinase A-dependent mechanism.

The pathologic and clinical intersection of atopic and autoimmune disease

Hypersensitivity reactions of the immune system have been broadly categorized into the atopic and autoimmune depending on whether the antigen triggering the reaction is endogenous (or self) or exogenous, the types of cellular and humoral components involved, and the clinical symptoms. Research into the pathophysiology of the resultant disease states has focused on a dichotomy between Th1 and Th2 T helper lymphocytes thought to govern autoimmune and atopic disease, respectively. Recent discoveries, however, have served to dispute this paradigm and have provided additional insight into the roles of Th17 cells, B-lymphocytes and T regulatory cells as well as the considerable communication and commonalities between the complex signaling pathways. Furthermore, clinical studies have served to challenge the idea that the presence of atopy and autoimmunity are mutually exclusive states. Finally, application of recent approaches to treatment-biologic targeted therapy in autoimmunity and induction of immune tolerance in atopic disease--to both disease states have shown mixed but promising results.

Regulatory-T, T-helper 1, and T-helper 2 cell differentiation in nasal mucosa of allergic rhinitis with olive pollen sensitivity

BACKGROUND

Allergic rhinitis (AR) is a disease in which T-helper (Th)2 response is predominant and its pathogenic mechanism is still poorly understood.

AIM

To evaluate the possible role of Th1, Th2 and regulatory-T (Treg) cells in the pathogenesis of AR.

METHODS

This case-control study enrolled 41 patients with seasonal AR (10-62 years old), sensitive to olive pollens, and 15 healthy controls (18-60 years old). Nasal biopsy was performed and specimens of nasal lavage fluid were obtained from all participants. The levels of interleukin (IL)-4, IL-10, interferon (IFN)-γ and transforming growth factor-β (TGF-β) were measured in nasal lavage fluid specimens. The expression of FOXP3, GATA-3 and T-bet was measured by immunohistochemical methods in the nasal biopsy specimens.

RESULTS

The levels of IFN-γ in the group with AR were significantly lower than those in the control group (p = 0.008). The levels of IL-4, IL-10 and TGF-β did not differ between the two groups. The expression of FOXP3 and T-bet in patients with AR was significantly lower than that in the control group (both p = 0.001). Expression of GATA-3 in the nasal mucosa was similar between the groups (p = 0.2). The ratios of T-bet/GATA-3 and FOXP3/GATA-3 in the AR group were significantly lower than those in the control group (p = 0.001).

CONCLUSION

Insufficient Treg and Th1 cells may be associated with the allergic inflammation that may be attributed to the Th2 immune response in patients suffering from AR who are sensitive to olive pollen.

A brief history of IL-9

IL-9 was first described in the late 1980s as a member of a growing number of cytokines that had pleiotropic functions in the immune system. Although many biological functions have been attributed to IL-9, it remains an understudied cytokine. A resurgence of interest in IL-9 has been spurred by recent work demonstrating a role for IL-9 in regulating inflammatory immunity and defining the transcription factors that activate the Il9 gene in cells that most efficiently produce IL-9. In this review, we summarize the characterization of IL-9 biological activities, highlight roles for the cytokine that are clearly defined, and outline questions regarding IL-9 functions that still require further exploration.