The translational repressor T-cell intracellular antigen-1 (TIA-1) is a key modulator of Th2 and Th17 responses driving pulmonary inflammation induced by exposure to house dust mite

Bibliometric Overview on T-Cell Intracellular Antigens and Their Pathological Implications

T-cell intracellular antigen 1 (TIA1) and TIA1-like/related protein (TIAL1/TIAR) are two members of the classical family of RNA binding proteins. Through their selective interactions with distinct RNAs and proteins, these multifunctional regulators are involved in chromatin remodeling, RNA splicing and processing and translation regulation, linking them to a wide range of diseases including neuronal disorders, cancer and other pathologies. From their discovery to the present day, many studies have focused on the behavior of these proteins in order to understand their impact on molecular and cellular processes and to understand their relationship to human pathologies. The volume of research on these proteins in various fields, including molecular biology, biochemistry, cell biology, immunology and cancer, has steadily increased, indicating a growing interest in these gene expression regulators among researchers. This information can be used to know the most productive institutions working in the field, understand the focus of research, identify key areas of involvement, delve deeper into their relationship and impact on different diseases, and to establish the level of study associated with them.

The Multifunctional Faces of T-Cell Intracellular Antigen 1 in Health and Disease

T-cell intracellular antigen 1 (TIA1) is an RNA-binding protein that is expressed in many tissues and in the vast majority of species, although it was first discovered as a component of human cytotoxic T lymphocytes. TIA1 has a dual localization in the nucleus and cytoplasm, where it plays an important role as a regulator of gene-expression flux. As a multifunctional master modulator, TIA1 controls biological processes relevant to the physiological functioning of the organism and the development and/or progression of several human pathologies. This review summarizes our current knowledge of the molecular aspects and cellular processes involving TIA1, with relevance for human pathophysiology.

Lessons from studying the AU-rich elements in chronic inflammation and autoimmunity

AU-rich elements (AREs) comprise one of the most widely studied families of regulatory RNA structures met in RNAs engaged in complex immunological reactions. A multitude of genetic, molecular, holistic and functional studies have been utilized for the analyses of the AREs and their interactions to proteins that bind to them. Data stemming from these studies brought forth a world of RNA-related check-points against infection, chronic inflammation, tumor associated immunity, and autoimmunity; and the interest to capitalize the interactions of AREs for clinical management and therapy. They also provided lessons on the cellular capabilities of post-transcriptional control. Originally thought as transcript-restricted regulators of turnover and translation, ARE-binding proteins do in fact harbor great versatility and interactivity across nuclear and cytoplasmic compartments; and act as functional coordinators of immune-cellular programs. Harnessing these deterministic functions requires extensive knowledge of their synergies or antagonisms at a cell-specific level; but holds great promise since it can provide the efficacy of combinatorial therapies with single agents.

STAT3 inhibition prevents lung inflammation, remodeling, and accumulation of Th2 and Th17 cells in a murine asthma model

BACKGROUND

STAT3 drives development of Th17 cells and cytokine production by Th2 and Th17 cells, which contribute to asthma. Alternative asthma treatments are needed, especially for the Th17 phenotype. We sought to determine whether C188-9, a small-molecule STAT3 inhibitor, can block Th2 and Th17 cell expansion and cytokine production to prevent house dust mite (HDM)-induced airway inflammation and remodeling.

METHODS

Three groups of C57BL/6 mice were treated intranasally (IN) and intraperitoneally (IP) daily for 3 weeks with the following: (i) vehicle 1 IN and vehicle 2 IP, (ii) HDM IN and vehicle 2 IP, or (iii) HDM IN and C188-9 IP. Sections of lung were stained with Alcian Blue/PAS and examined microscopically. Total (t) STAT3, STAT3 phosphorylated on Y705 (pSTAT3), IL-17, IL-13, IL-5, and IL-4 levels were measured in lung protein extracts and serum using Luminex beads. Frequencies of Th2-type and Th17-type lymphocytes were assessed in lungs and bronchoalveolar lavage fluid (BALF) by multiparametric flow cytometry.

RESULTS

HDM inhalation markedly increased airway goblet cell numbers and thickness of the epithelium and subepithelial smooth muscle layer, which was accompanied in the whole lung by increased pSTAT3, IL-4, IL-5, IL-13, and IL-17, and % CD4⁺ T cells that produce IL-5, IL-13, and IL-17. HDM inhalation also increased serum IL-4 and IL-17 levels and increased BALF % CD4⁺ T cells that produce IL-5 and IL-13. Remarkably, treatment with C188-9 normalized each endpoint.

CONCLUSION

HDM-induced airway inflammation, remodeling, and Th2/Th17-type cell accumulation involve STAT3 activation that can be prevented by C188-9 treatment.

T-cell intracellular antigens in health and disease

T-cell intracellular antigen 1 (TIA1) and TIA1-related/like protein (TIAR/TIAL1) are 2 proteins discovered in 1991 as components of cytotoxic T lymphocyte granules. They act in the nucleus as regulators of transcription and pre-mRNA splicing. In the cytoplasm, TIA1 and TIAR regulate and/or modulate the location, stability and/or translation of mRNAs. As knowledge of the different genes regulated by these proteins and the cellular/biological programs in which they are involved increases, it is evident that these antigens are key players in human physiology and pathology. This review will discuss the latest developments in the field, with physiopathological relevance, that point to novel roles for these regulators in the molecular and cell biology of higher eukaryotes.

Post-transcriptional coordination of immunological responses by RNA-binding proteins

Immunological reactions are propelled by ever-changing signals that alter the translational ability of the RNA in the cells involved. Such alterations are considered to be consequential modifications in the transcriptomic decoding of the genetic blueprint. The identification of RNA-binding protein (RBP) assemblies engaged in the coordinative regulation of state-specific RNAs indicates alternative and exclusive means for determining the activation, plasticity and tolerance of cells of the immune system. Here we review current knowledge about RBP-regulated post-transcriptional events involved in the reactivity of cells of the immune system and the importance of their alteration during chronic inflammatory pathology and autoimmunity.

Noncoding RNA and its associated proteins as regulatory elements of the immune system

The rapid changes in gene expression that accompany developmental transitions, stress responses and proliferation are controlled by signal-mediated coordination of transcriptional and post-transcriptional mechanisms. In recent years, understanding of the mechanics of these processes and the contexts in which they are employed during hematopoiesis and immune challenge has increased. An important aspect of this progress is recognition of the importance of RNA-binding proteins and noncoding RNAs. These have roles in the development and function of the immune system and in pathogen life cycles, and they represent an important aspect of intracellular immunity.

The effect of oral tolerance on the allergic airway response in younger and aged mice

BACKGROUND

The effect of increased age on the induction of oral tolerance by low-dose antigen feeding and its effect on the response to antigen airway challenge in aged mice have not been well characterized.

OBJECTIVE

To determine whether oral tolerance can be induced in aged mice and its impact on the development of allergic airway inflammation.

METHODS

Younger (6 weeks old) and aged (18 months old) mice were fed ovalbumin (OVA) prior to sensitization to induce antigen tolerance. Serum antigen-specific immunoglobulins (Igs), bronchoalveolar lavage fluid (BALF), lung histology, enumeration of CD4 + Foxp3+ Treg cells, and airway hyperresponsiveness (AHR) were determined after the final antigen challenge.

RESULTS

Feeding antigen to aged mice prior to sensitization induced oral tolerance as determined by a decrease in antigen-specific IgE and IgG(1); however, the effect was greater in younger mice. Induction of oral tolerance was associated with a greater increase in airway Treg cells in the younger mice. Despite these differences, oral tolerance significantly suppressed features of asthma in aged mice, including BALF total cell and eosinophil numbers, cytokine production, and AHR.

CONCLUSIONS

Aged mice developed oral tolerance to antigen, which suppressed several features of allergic airway inflammation.

Anti-cancer versus cancer-promoting effects of the interleukin-17-producing T helper cells

Research on T helper 17 (Th17) cells with regard to immunoediting has revealed elusive results. Whereas enhanced Th17 response and related molecules such as interleukin (IL)-17, IL-21, IL-22, IL-23 and STAT3 accompanied tumor induction and progression, finding that tumor growth/stage was negatively correlated with increased infiltration of Th17 cells in the tumor mass has prompted elucidation of various antitumor mechanisms elicited by Th17 and their related molecules. The pro-tumor efficacy of Th17 response included promotion of neutrophilia and induction of angiogenic (e.g. VEGF, MMP2 and MMP9) and anti-apoptotic factors (e.g. Bcl-XL), as well as expansion and activation of myeloid-derived suppressor cells, which facilitate generation of tumor-specific regulatory T cells. Other tumor immunogenic settings revealed anti-tumor pathways including induction of cytotoxic activity, expression of MHC antigens, the ability Th17 cells to reside within the tumor, and to convert into IFN-γ producers. Notably, Th17 cell related molecules exert indirect pro- or anti-tumor effects via inducing viral persistence or mediating protective mechanisms against bacterial and viral infection. Herein, the recent literature revealing such immunoediting events mediated by Th17 cells and their associated molecules as delivered by various experimental regimens and observed in cancer patient are revised, with a focus on some proposed anti-cancer therapies.

Key molecules in the differentiation and commitment program of T helper 17 (Th17) cells up-to-date

The mechanisms underlying autoimmunity and cancer remain elusive. However, perpendicular evidence has been evolved in the past decade that T helper (Th)17 cells and their related molecules are implicated in initiation and induction of various disease settings including both diseases. Meanwhile, extensive research on Th17 cells elucidated various molecules including cytokines and transcription factors as well as signaling pathways involved in the differentiation, maturation, survival and ultimate commitment of Th17 cells. In the current review, we revise the mechanistic underpinnings delivered by recent research on these molecules in the Th17 differentiation/commitment concert. We emphasize on those molecules proposed as targets for attaining potential therapies of various autoimmune disorders and cancer, aiming both at dampening the dark-side of Th17 repertoire and simultaneously potentiating its benefits in the roster of the antimicrobial response.