Connection between γδ T-cell- and Adenosine- Mediated Immune Regulation in the Pathogenesis of Experimental Autoimmune Uveitis

γδ T cells in autoimmune uveitis pathogenesis: A promising therapeutic target

Autoimmune uveitis is a non-infectious, inflammatory intraocular disease that affects the uveal and adjacent tissues. It frequently causes varying degrees of visual loss. Evidence for the strong association between activated γδ T cells and the development of autoimmune uveitis is growing. The innate and adaptive immune response are connected in the early phases by the γδ T cells that contain the γ and δ chains. γδ T cells can identify antigens in a manner that is not constrained by the MHC. When activated by various pathways, γδ T cells can not only secrete pro-inflammatory factors early on (such as IL-17), but they can also promote Th17 cells responses, which ultimately exacerbates autoimmune uveitis. Therefore, we review the mechanisms by which γδ T cells affect autoimmune uveitis in different activation and disease states. Moreover, we also prospect for immunotherapies targeting different γδ T cell-related action pathways, providing a reference for exploring new drug for the treatment of autoimmune uveitis.

Bisphosphonates Related Ocular Side Effects: A Case Series and Review of Literature

OBJECTIVE

To describe the clinical features of patients with bisphosphonate related ocular side effects (BROSE).

METHODS

The medical records of all patients with BROSE between January 2009 and December 2019 were reviewed.

RESULTS

Nine cases with BROSE were identified. All subjects were female. Median age at diagnosis was of 69 years. The leading indication for bisphosphonate treatment was osteoporosis (n=7), Paget's disease of bone (n=1) and breast cancer (n=1). Six (66.67%) patients presented with uveitis, one (11%) episcleritis and two (22%) with orbital inflammation. Five events (55.5%) occurred within 10 days of initiating the bisphosphonate and the rest (44.44%) developed within 2 weeks to 3 years later. Four (44.44%) patients had concurrent thyroid disease. An association was found between underlying thyroid disease or autoimmunity.

CONCLUSION

BROSE is an uncommon complication of bisphosphonate therapy occurring more frequently in patients with an autoimmune predisposition.

Mesenchymal Stem Cell-Derived Secretome: A Potential Therapeutic Option for Autoimmune and Immune-Mediated Inflammatory Diseases

Immune-mediated inflammatory diseases (IMIDs) encompass several entities such as "classic" autoimmune disorders or immune-mediated diseases with autoinflammatory characteristics. Adult stem cells including mesenchymal stem cells (MSCs) are by far the most commonly used type in clinical practice. However, due to the possible side effects of MSC-based treatments, there is an increase in interest in the MSC-secretome (containing large extracellular vesicles, microvesicles, and exosomes) as an alternative therapeutic option in IMIDs. A wide spectrum of MSC-secretome-related biological activities has been proven thus far including anti-inflammatory, anti-apoptotic, and immunomodulatory properties. In comparison with MSCs, the secretome is less immunogenic but exerts similar biological actions, so it can be considered as an ideal cell-free therapeutic alternative. Additionally, since the composition of the MSC-secretome can be engineered, for a future perspective, it could also be viewed as part of a potential delivery system within nanomedicine, allowing us to specifically target dysfunctional cells or tissues. Although many encouraging results from pre-clinical studies have recently been obtained that strongly support the application of the MSC-secretome in IMIDs, human studies with MSC-secretome administration are still in their infancy. This article reviews the immunomodulatory effects of the MSC-secretome in IMIDs and provides insight into the interpretation of its beneficial biological actions.

Adenosine: The common target between cancer immunotherapy and glaucoma in the eye

Adenosine, an endogenous purine nucleoside, is a well-known actor of the immune system and the inflammatory response both in physiologic and pathologic conditions. By acting upon particular, G-protein coupled adenosine receptors, i.e., A1, A2- a & b, and A3 receptors mediate a variety of intracellular and immunomodulatory actions. Several studies have elucidated Adenosine's effect and its up-and downstream molecules and enzymes on the anti-tumor response against several types of cancers. We have also targeted a couple of molecules to manipulate this pathway and get the immune system's desired response in our previous experiences. Besides, the outgrowth of the studies on ocular Adenosine in recent years has significantly enhanced the knowledge about Adenosine and its role in ocular immunology and the inflammatory response of the eye. Glaucoma is the second leading cause of blindness globally, and the recent application of Adenosine and its derivatives has shown the critical role of the adenosine pathway in its pathophysiology. However, despite a very promising background, the phase III clinical trial of Trabodenoson failed to achieve the non-inferiority goals of the study. In this review, we discuss different aspects of the abovementioned pathway in ophthalmology and ocular immunology; following a brief evaluation of the current immunotherapeutic strategies, we try to elucidate the links between cancer immunotherapy and glaucoma in order to introduce novel therapeutic targets for glaucoma.

Immune Effects of γδ T Cells in Colorectal Cancer: A Review

Gamma delta (γδ) T cells can effectively recognize and kill colorectal cancer (CRC) cells, thereby suppressing tumor progression via multiple mechanisms. They also have abilities to exert a protumor effect via secreting interleukin-17 (IL-17). γδ T cells have been selected as potential immunocytes for antitumor treatment because of their significant cytotoxic activity. Immunotherapy is another potential anti-CRC strategy after an operation, chemotherapy, and radiotherapy. γδ T cell-based immunotherapy for CRC shows fewer side effects and better toleration. This review will outline the immune functions and the mechanisms of γδ T cells in the growth and progression of CRC in recent years, and summarize the immunotherapies based on γδ T cells, thus providing a direction for future γδ T cells in CRC research.

Common innate pathways to autoimmune disease

Until recently, autoimmune disease research has primarily been focused on elucidating the role of the adaptive immune system. In the past decade or so, the role of the innate immune system in the pathogenesis of autoimmunity has increasingly been realized. Recent findings have elucidated paradigm-shifting concepts, for example, the implications of "trained immunity" and a dysbiotic microbiome in the susceptibility of predisposed individuals to clinical autoimmunity. In addition, the application of modern technologies such as the quantum dot (Qdot) system and 'Omics' (e.g., genomics, proteomics, and metabolomics) data-processing tools has proven fruitful in revisiting mechanisms underlying autoimmune pathogenesis and in identifying novel therapeutic targets. This review highlights recent findings discussed at the American Autoimmune Related Disease Association (AARDA) 2019 colloquium. The findings covering autoimmune diseases and autoinflammatory diseases illustrate how new developments in common innate immune pathways can contribute to the better understanding and management of these immune-mediated disorders.