Tear Cytokines as Biomarkers for Acute Ocular Graft-Versus-Host Disease

Lessons Learned From Ocular Graft versus Host Disease: An Ocular Surface Inflammatory Disease of Known Time of Onset

ABSTRACT

The ocular surface inflammatory disorders (OSIDs) comprise a group of conditions characterized by persistent inflammation of the ocular surface and adnexal tissues. Systemic autoimmune diseases and hypersensitivity reactions cause them, and, if left untreated, can result in severe inflammatory dry eye, corneal damage, and vision loss. Ocular graft-versus-host disease (oGVHD) forms part of the ocular surface inflammatory disease umbrella. It is a condition occurring after allogeneic hematopoietic stem cell or bone marrow transplantation, usually in chronic graft-versus-host disease. oGVHD can virtually affect any ocular adnexal tissue, especially the meibomian glands, and cause persistent inflammation, tissue fibrosis, and subsequent chronic, severe dry eye disease. Among the OSIDs, oGVHD has the particularity that it has a "time zero," meaning we know when the disease started. As such, preclinical models have leveraged this to investigate the molecular mechanisms involved in the damage oGVHD causes to the ocular surface. In oGVHD, establishing a "time zero" allows for predicting the clinical course and establishing adequate treatment. This is also possible because the inflammatory infiltration occurs in ocular surface tissues, which are readily accessible. Using oGVHD, we might be able to understand the immune response mechanisms in other OSIDs better (i.e., Sjögren syndrome, Stevens-Johnson syndrome, among others). This review presents an up-to-date overview of the pathogenesis, clinical presentation, and treatment of oGVHD. In addition, we will discuss the value of the "time zero" concept in the study of oGVHD.

Molecular Biomarkers in Ocular Graft-versus-Host Disease: A Systematic Review

Ocular graft-versus-host disease (oGVHD) affects ~50% of post-stem cell transplant patients and is the only form of GVHD diagnosed without a biopsy. As it must be distinguished from other dry eye diseases, there is a need to identify oGVHD biomarkers to improve diagnosis and treatment. We conducted a systematic review of 19 scholarly articles published from 2018 to 2023 including articles focused on adult patients diagnosed with oGVHD following allogeneic hematopoietic stem cell transplant and used biomarkers as the outcome measure. Articles that were not original investigations or were not published in English were excluded. These clinical investigations explored different molecular oGVHD biomarkers and were identified on 3 October 2023 from the Scopus, PubMed, and Embase databases by using search terms including ocular graft-versus-host disease, biomarkers, cytokines, proteomics, genomics, immune response, imaging techniques, and dry-eye-related key terms. The Newcastle-Ottawa scale for case-control studies was used to assess bias. From the 19 articles included, cytokine, proteomic, lipid, and leukocyte profiles were studied in tear film, as well as ocular surface microbiota and fluorescein staining. Our findings suggest that cytokine profiling is the most studied oGVHD biomarker. Additionally, variations correlating these biomarkers with disease state may lead to a more targeted diagnosis and therapeutic approach. Limitations include language bias, publication bias, and sampling bias, as well as a lack of appropriate controls for included studies.

Proportion and characteristics of lacrimal drainage pathway disease and keratopathy in non-infectious corneal perforation using lacrimal syringing test

Lacrimal drainage pathway disease-associated keratopathy (LDAK) has been associated with corneal perforation, which arises from both infectious and non-infectious corneal disorders. However, patients with corneal perforation are often not routinely tested for LDAK, and the potential risk posed by LDAK in the development of corneal ulcers has not been investigated in detail. This study aimed to assess the proportion and characteristics of LDAK in patients with non-infectious corneal perforation using lacrimal syringing test. This study enrolled 56 patients with corneal perforation treated at Saitama Medical University Hospital between January 2016 and September 2022. The causes of corneal perforation were trauma (n = 17, 30%), infection (n = 19, 34%), non-infection (n = 16, 29%), and unknown (n = 4, 7%). A lacrimal syringing test was performed on 12 patients with non-infectious corneal perforation and 4 with an unknown diagnosis. Among the 16 patients with non-infectious corneal perforation, 13 (81%) had lacrimal drainage disease, but only 3 (19%) patients had lacrimal puncta, as revealed by slit-lamp examinations. The primary bacterial species identified in lacrimal obstructive disease and lacrimal canaliculitis were Staphylococcus spp. and Actinomycetes spp. respectively. Lower temporal and peripheral corneal perforations were common. All patients underwent lacrimal surgery, and 6 (38%) were treated for corneal perforation without corneal surgery. Interestingly, several patients with LDAK who did not exhibit any lacrimal duct obstruction on slit-lamp examination. The study findings demonstrate the significance of the lacrimal syringing test for assessing LDAK in patients with corneal perforation, indicating LDAK as a potential cause of corneal perforation.