Pioglitazone alleviates lacrimal gland impairments induced by high-fat diet by suppressing M1 polarization.

A high-fat diet (HFD) contributes to the pathogenesis of various inflammatory and metabolic diseases. Previous research confirms that under HFD conditions, the extraorbital lacrimal glands (ELGs) can be impaired, with significant infiltration of pro-inflammatory macrophages (Mps). However, the relationship between HFD and Mps polarization in the ELGs remains unexplored. We first identified and validated the differential expression of PPAR-γ in murine ELGs fed ND and HFD through RNA sequencing. Tear secretion was measured using the Schirmer test. Lipid droplet deposition within the ELGs was observed through Oil Red O staining and transmission electron microscopy. Mps phenotypes were determined through quantitative RT-PCR, immunofluorescence, and flow cytometric analysis. An in vitro high-fat culture system for Mps was established using palmitic acid (PA), with supernatants collected for co-culture with lacrimal gland acinar cells. Gene expression was determined through ELISA, immunofluorescence, immunohistochemistry, quantitative RT-PCR, and Western blot analysis. Pioglitazone reduced M1-predominant infiltration induced by HFD by increasing PPAR-γ levels in ELGs, thereby alleviating lipid deposition and enhancing tear secretion. In vitro tests indicated that PPAR-γ agonist shifted Mps from M1-predominant to M2-predominant phenotype in PA-induced Mps, reducing lipid synthesis in LGACs and promoting lipid catabolism, thus alleviating lipid metabolic disorders within ELGs. Conversely, the PPAR-γ antagonist induced opposite effects. In summary, the lacrimal gland is highly sensitive to high-fat and lipid metabolic disorders. Downregulation of PPAR-γ expression in ELGs induces Mps polarization toward predominantly M1 phenotype, leading to lipid metabolic disorder and inflammatory responses via the NF-κb/ERK/JNK/P38 pathway.

Discovery and Verification of Sjögren's Syndrome Protein Biomarkers in Tears by Targeted LC-MRM.

Sjögren's syndrome (SS) is an autoimmune rheumatic disorder characterized by exocrine gland dysfunction, mainly from the lacrimal and salivary glands. The disease causes severe aqueous dry eye syndrome (DED) and is associated with high rates of complications, including corneal ulceration, scaring, and perforation. Systemic complications may occur as well as a higher risk of developing lymphoma. Diagnosis of SS-DED is often delayed and difficult to establish. With the aim of discovering biomarkers to help discriminate SS-DED patients, a combination of untargeted and targeted LC-MS/MS analyses were performed on tear samples collected on Schirmer strips and subjected to tryptic digestion. Following the analysis of three cohorts and the development of two targeted LC-sMRM methods for the verification of putative biomarkers found in the first cohort of samples, 64 proteins could be linked to Sjögren's syndrome, in the hopes of helping to confirm diagnoses as well as potentially stratifying the severity of disease in these patients. Proteins that were increased in SS-DED showed activation of the immune system and alterations in homeostasis. Several proteases and protease inhibitors were found to be significantly changing in SS-DED, as well as a consistent decrease in specific proteins known to be secreted by the lacrimal gland.

IL-27 promotes pathogenic T cells in a mouse model of Sjögren's disease.

Sjögren's disease (SjD) is a chronic autoimmune disease characterized by focal lymphocytic inflammation in lacrimal and salivary glands. We recently identified IL-27 as a requisite signal for the spontaneous SjD-like manifestations in nonobese diabetic (NOD) mice. Here, we define T cell-intrinsic effects of IL-27 in lacrimal gland disease in NOD mice. IL-27 receptor was required by both CD4 T effector (Te) cells and CD8 T cells to mediate focal inflammation. Intrinsic IL-27 signaling was associated with PD-1 and ICOS expressing T follicular helper (Tfh)-like CD4 Te cells within lacrimal glands, including subsets defined by CD73 or CD39 expression. CD8 T cells capable of IL-27 signaling also expressed PD-1 with subsets expressing ICOS and CD73 demonstrating a T follicular cytotoxic (Tfc)-like cell phenotype and others expressing a CD39hi exhausted-like phenotype. These findings suggest IL-27 is a key early signal driving a follicular-type response in lacrimal gland inflammation in NOD mice.

Neoadjuvant Intra-arterial Cytoreductive Chemotherapy Improves Outcomes in Lacrimal Gland Adenoid Cystic Carcinoma.

BACKGROUND: Lacrimal gland adenoid cystic carcinoma (LGACC) has historically been associated with a poor prognosis even with localized disease, with a survival of 56% at 5 years. In 1988, we treated the first patient with neoadjuvant intra-arterial cytoreductive chemotherapy (IACC). Since then, we have used this protocol as the standard approach. We aim to analyze the outcomes of patients with LGACC treated with the protocol and compare them to a population-based cohort to assess if IACC can improve survival. METHODS: We prospectively assessed all non-metastatic patients with LGACC treated with IACC at a single institution between 1988 and 2021. For a comparison group, we identified all non-metastatic patients with LGACC treated with excision from the Surveillance, Epidemiology, and End Results (SEER) registry. We calculated disease-specific survival using the Kaplan-Meier and Cox proportional-hazards modeling methods. RESULTS: Thirty-five non-metastatic patients with LGACC treated with IACC were identified at a single institution, and 64 patients with non-metastatic LGACC treated with excision were identified in the SEER database. The 5- and 10-year disease-specific survival rates for patients treated with IACC were 84% (95%CI 71-97) and 76% (95%CI 60-92), respectively. While the 5- and 10-year disease-specific survival rates for the population-based cohort were 72% (95%CI 62-82) and 46% (95%CI 32-60). The survival analysis favored IACC, with a 60% lower risk of death (HR: 0.4; 95%CI 0.2-0.9). CONCLUSION: IACC improves disease-specific survival in comparison to a population-based cohort treated with excision. Additional patients treated with IACC at multiple institutions are required to provide further external validity.

ER-1 deficiency induces inflammation and lipid deposition in meibomian gland and lacrimal gland.

PURPOSE: To investigated the role of estrogen receptor-1 (ER-1) in maintaining homeostasis in ocular surface. METHODS: ER-1-knockout (ER-1KO) mice were studied at 4 months of age. The ocular surface was examined using a slit lamp. Histological alterations in the meibomian gland (MG) and lacrimal gland (LG) were observed with H&E staining. Protein levels of P-ERK, peroxisome proliferator-activated receptor gamma (PPAR-γ), p-NFκB-P65, IL-1ß, aquaporin 5 (AQP-5), fatty acid-binding protein 5 (Fabp5) and K10 were determined by immunofluorescence and Western blotting. Gene expressions of APO-F, APO-E, K10, ELOVL4, PPAR-γ, SCD-1, and SREBP1 were quantified by qPCR. Conjunctival (CJ) goblet cell alterations were detected by PAS staining. Lipid metabolism in MG and LG was assessed using LipidTox. Apoptosis in MG and LG was analyzed through the TUNEL assay. RESULTS: Both male and female ER-1KO mice demonstrated increased corneal fluorescence staining scores. MG showed abnormal lipid metabolism and ductal dilation. LG displayed lipid deposition and reduced AQP-5 expression. CJ experienced goblet cell loss. MG, LG exhibited signs of inflammation and apoptosis. CONCLUSION: ER1 is pivotal for ocular surface homeostasis in both genders of mice. ER1 deficiency induces inflammation and lipid deposition to MG and LG, culminating in dry eye-like manifestations on the ocular surface.

Hyperglycemia Induces Tear Reduction and Dry Eye in Diabetic Mice through the Norepinephrine-α1 Adrenergic Receptor-Mitochondrial Impairment Axis of Lacrimal Gland.

Dry eye syndrome is a common complication in diabetic patients with a prevalence of up to 54.3%. However, the pathogenic mechanisms underlying hyperglycemia-induced tear reduction and dry eye remain less understood. The present study indicated that both norepinephrine (NE) and tyrosine hydroxylase levels were elevated in the lacrimal gland of diabetic mice, accompanied by increased Fos proto-oncogene (c-FOS)+ cells in the superior cervical ganglion. However, the elimination of NE accumulation by surgical and chemical sympathectomy significantly ameliorated the reduction in tear production, suppressed abnormal inflammation of the lacrimal gland, and improved the severity of dry eye symptoms in diabetic mice. Among various adrenergic receptors (ARs), the α1 subtype played a predominant role in the regulation of tear production, as treatments of α1AR antagonists improved tear secretion in diabetic mice compared with ßAR antagonist propranolol. Moreover, the α1AR antagonist alfuzosin treatment also alleviated functional impairments of the meibomian gland and goblet cells in diabetic mice. Mechanically, the α1AR antagonist rescued the mitochondrial bioenergetic deficit, increased the mitochondrial DNA copy numbers, and elevated the glutathione levels of the diabetic lacrimal gland. Overall, these results deciphered a previously unrecognized involvement of the NE-α1AR-mitochondrial bioenergetics axis in the regulation of tear production in the lacrimal gland, which may provide a potential strategy to counteract diabetic dry eye by interfering with the α1AR activity.

Precise longitudinal monitoring of corneal change through in vivo confocal microscopy in a rat dry eye disease model.

Purpose: While lacrimal gland removal is commonly used in animal models to replicate dry eye disease, research into systematically monitoring dry eye disease's longitudinal pathological changes is limited. In vivo confocal microscopy (Heidelberg Retina Tomograph 3 with a Rostock Cornea Module, Heidelberg Engineering Inc., Franklin, MA) can non-invasively reveal corneal histopathological structures. To monitor dry-eye-disease-related changes in corneal structures, we developed a precise monitoring method using in vivo confocal microscopy in a rat double lacrimal gland removal model. Methods: Five Sprague-Dawley rats (age 8-9 weeks, male) underwent double lacrimal gland removal. Modified Schirmer's tear test, blink tests, and in vivo confocal microscopy images were acquired pre-surgery and at 1, 2, and 4 weeks post-surgery. Three individual stromal nerves were selected per eye as guide images, and images of the corresponding sub-basal nerve plexus area were acquired via volume acquisition. The same area was re-imaged in subsequent weeks. Results: After double lacrimal gland removal, tear production was reduced by 60%, and the blink rate increased 10 times compared to pre-surgery. Starting from 1 week after surgery, in vivo confocal microscopy showed increased sub-basal nerve plexus nerve fiber density with inflammatory cell infiltration at the sub-basal nerve plexus layer and remained at an elevated level at 2 and 4 weeks post-surgery. Conclusions: We demonstrated that our precise monitoring method revealed detailed changes in the corneal nerves, the epithelium, and the stroma.

Developing a model for aqueous deficient dry eye secondary to periglandular cicatrizing conjunctivitis.

PURPOSE: The current study used various techniques to develop a rabbit animal model of lacrimal gland damage caused by scarring conjunctivitis in the periglandular area. METHODS: Left eyes of New Zealand white rabbits were injected with 0.1 ml of 1M NaOH subconjunctivally around superior and inferior lacrimal gland orifices (Group 1, n = 4), touched with 1M NaOH for 100 s to the superior and inferior fornices with conjunctival denuding (Group 2; n = 4), and electrocauterization to the ductal opening area (Group 3; n = 4). The ocular surface staining, Schirmer I, lacrimal gland, and conjunctival changes were observed at baseline,1, 4, 8, and 12 weeks. The degree of glandular inflammation, conjunctival fibrosis (Masson Trichrome), and goblet cell density (PAS) were also assessed. RESULTS: At 12 weeks, the lacrimal glands of group 1 rabbits with periglandular injection showed severe inflammation with mean four foci/10HPF and a significant mean reduction in the Schirmer values by 7.6 mm (P = 0.007). Lacrimal glands had diffuse acinar atrophy, loss of myoepithelial cells, and ductular dilatation. The overlying conjunctiva showed fibrosis, goblet cell loss, and corneal vascularization in the inferotemporal quadrant. No lacrimal gland or ocular surface changes were observed in groups 2 and 3 at 12 weeks, except for localized subconjunctival fibrosis. CONCLUSION: Periglandular injection of 0.1 ml of 1M NaOH induced extensive lacrimal gland damage with reduced secretion and scarring in the subconjunctival plane compared to direct cauterization or direct NaOH contact to the ductal orifices of the rabbit lacrimal gland.

S100A9-TLR4 axis aggravates dry eye through the blockage of autophagy.

This research focused on how upregulation of S100A9 contributed to the pathogenesis of the dry eye disease (DED) and whether S100A9 served as a promising therapeutic target in DED. Public single-cell RNA sequencing (scRNA-seq) data of a lacrimal gland excision (LGE) murine DED model was analyzed. LGE model was established and expression of protein was measured through immunofluorescence and Western blot. DED-related signs were evaluated through tear secretion and fluorescent staining. TUNEL was performed to detect the level of cell death. Briefly, S100A9 was recognized as a highly variable gene in the DED group. LGE model was successfully established, and S100A9 showed a time-dependent increase in the corneal epithelia. Autophagic blockage was predicted by the scRNA-seq data in DED, and further verified by decrease of LC3B-II/LC3B-I and increase of SQSTM1 and p-mTOR/mTOR, while S100A9 inhibitor paquinimod (PAQ) reversed the changes. PAQ also downregulated TLR4, and inhibition of TLR4 also alleviated autophagic blockage in DED. Finally, signs of DED, chronic corneal inflammation and cell death got a remission after either inhibition of S100A9 or TLR4. In general, we deduced a S100A9-TLR4-Autophagic blockage pathway in the pathogenesis of DED.

AS101 regulates the Teff/Treg balance to alleviate rabbit autoimmune dacryoadenitis through modulating NFATc2.

Sjögren's syndrome (SS) dry eye can cause ocular surface inflammation and lacrimal gland (LG) damage, leading to discomfort and potential vision problems. The existing treatment options for SS dry eye are currently constrained. We investigated the possible therapeutic effect and the underlying mechanism of AS101 in autoimmune dry eye. AS101 was injected subconjunctivally into a rabbit model of autoimmune dacryoadenitis and its therapeutic effects were determined by evaluating clinical and histological scores. The expressions of effector T cells (Teff)/regulatory T cells (Treg)-related transcription factors and cytokines, inflammation mediators, and transcription factor NFATc2 were measured by quantitative real-time PCR and/or Western blot both in vivo and in vitro. Additionally, the role of NFATc2 in the immunomodulatory effects of AS101 on T cells was explored by co-culturing activated peripheral blood lymphocytes (PBLs) transfected with NFATc2 overexpression lentiviral plasmid with AS101. AS101 treatment potently ameliorated the clinical severity and reduced the inflammation of LG. Further investigation revealed that AS101 treatment led to decreased expression of Th1-related genes (T-bet and IFN-γ) and Th17-related genes (RORC, IL-17A, IL-17F, and GM-CSF) and increased expression of Treg-related gene Foxp3 in vivo and in vitro. Meanwhile, AS101 suppressed the expression of TNF-α, IL-1ß, IL-23, IL-6, MMP-2, and MMP-9. Mechanistically, AS101 downregulated the expression of NFATc2 in inflamed LGs. Overexpression of NFATc2 in activated PBLs partially blunted the effect of AS101 on Teff suppression and Treg promotion. In conclusion, AS101 is a potential regulator of Teff/Treg cell balance and could be an effective treatment agent for SS dry eye.

GPC4 truncating variant associated with Keipert syndrome and lacrimal punctal agenesis.

Lacrimal punctal agenesis is an extremely rare condition with an unclear genetic basis. Here, we report a 3-year-old male patient harboring a hemizygous variant in glypican 4 (GPC4), which causes Keipert syndrome, who presented with complete lacrimal punctal agenesis, distinctive craniofacial features, mild developmental delay, mild intellectual disability, and autism. The craniofacial features included a prominent forehead, epicanthus, depressed and broad nasal bridge, hypoplastic columella, midface hypoplasia, tented upper lip, and low-set ears. Proband exome sequencing identified a hemizygous variant in GPC4: NM_001448.3:c.1051C > T (p.Arg351*). The GPC4 variant was inherited from his heterozygous mother; X-inactivation followed a skewed pattern in his mother. This patient demonstrated clinical features consistent with Keipert syndrome including craniofacial features, brachydactyly, broad distal phalanx, broad first toe, and mild developmental delay; however, agenesis of the lacrimal puncta has not been reported previously in Keipert syndrome. Our findings suggest that GPC4, which encodes a heparan-sulfate proteoglycan, may play an important role in lacrimal morphogenesis. Our observations also suggest that Keipert syndrome should be considered in patients with lacrimal punctal agenesis.

Electroacupuncture modulates the TLR4-NF-κB inflammatory signaling pathway to attenuate ocular surface inflammation in dry eyes of type 2 diabetic rats.

Bioinformatics analysis was performed to reveal the underlying pathogenesis of type 2 diabetes (T2DM) dry eye(DE) and to predict the core targets and potential pathways for electroacupuncture (EA) treatment of T2DM DE, in which key targets such as Toll-likereceptor4 (TLR4), NF-κB and Tumor necrosis factor-α (TNF-α) may be involved. Next, streptozotocin and a high-fat diet were used to generate T2DM-DE rats. Randomly picked EA, fluorometholone, model, and sham EA groups were created from successfully modelled T2DM DE rats. Six more rats were chosen as the blank group from among the normal rats. The results of DE index showed that EA improved the ocular surface symptoms.HE staining showed that EA attenuated the pathological changes in the cornea, conjunctiva and lacrimal gland of T2DM DE rats. EA decreased the expression of TLR4, MyD88, P-NF-κB P65, and TNF-α in the cornea, conjunctiva, and lacrimal gland, in accordance with immunofluorescence and Western blot data. Thus, EA reduced ocular surface symptoms and improved pathological changes of cornea, conjunctiva, and lacrimal gland induced by T2DM DE inT2DM DE rats, and the mechanism may be related to the inhibition of overactivation of the TLR4/NF-κB signaling pathway by EA and thus attenuating ocular surface inflammation.

Congenital solitary osseous choristoma of the left lateral canthus: a case report.

BACKGROUND: An ocular osseous choristoma is a growth of mature, compact bone in the ocular or periocular soft tissue, and it is the rarest form of ocular choristoma, accounting for only 1.7% of all epibulbar choristomas. CASE PRESENTATION: Herein we present the case of a 20-month-old girl who was referred to the oculoplasty clinic with a progressively growing mass in the left lateral canthus. It had been present since birth without ocular involvement. Upon examination the mass was firm with a smooth surface, measured 9 × 6 × 3 mm, and exhibited no episcleral attachment or ocular involvement. An excisional biopsy was performed, and the histopathological findings were consistent with osseous choristoma of the left lateral canthus. CONCLUSIONS: This report highlights the importance of considering osseous choristoma in the differential diagnosis of eyelid lesions, particularly those that have been present since birth. It also emphasizes the need for further studies investigating associations between osseous choristomas and ocular canthi.

Repeated Lacrimal Gland Biopsies.

PURPOSE: To examine the indications for repeated lacrimal gland biopsies, and the rate of detection of a new diagnosis. METHODS: A single-center, retrospective review of patients who underwent more than 1 lacrimal gland biopsy, either ipsilateral or contralateral, between 2000 and 2022. RESULTS: One hundred and twenty-three patients (80 female; 65%) had repeated lacrimal gland biopsy. The commonest diagnosis on initial biopsy was chronic nonspecific dacryoadenitis (NSD) (49/123; 40%). Indications for repeated biopsy were uncertainty in making a histopathological diagnosis (16/123; 13%), poorly-responsive or recurrent ipsilateral disease (61/123; 50%), new or continued/worsening contralateral disease (30 patients; 24%), and planned tumor resection after initial biopsy (16/123; 13%). Of the 40 patients (33%) with a different histopathological diagnosis after repeated lacrimal biopsy, 4 (10%) had lymphoma, initially reported as NSD (4/49 with NSD; 8%), and 7/40 (18%) (14% of the 49 NSD patients) were reclassified as having specific inflammations (including 2 with granulomatous polyangiitis); of the 7 having reclassification as a specific dacryoadenitis, 6/7 had ipsilateral disease failing to respond to primary treatment, and 1/7 had new onset or progression of contralateral disease. All histology after the primary biopsy of 16 patients with lacrimal gland malignancies retained the same tissue diagnosis. CONCLUSION: Repeated biopsy for lacrimal gland disease in this study revealed a diagnosis of malignancy in 20%, including lymphoma in 8% of those initially diagnosed with NSD. There was a 14% rate of diagnostic progression from "non-specific" dacryoadenitis to a more specific inflammatory disease.

Bilateral Superior Ophthalmic Vein Involvement in a Case With Orbital Sarcoidosis.

A 71-year-old Japanese man presented with a 2-month history of diplopia. He had been followed up at another hospital for ocular sarcoidosis for 3 years. On initial consultation, the best-corrected decimal visual acuity was 0.3 on OU. Slit-lamp and funduscopic examinations were unremarkable. The left lacrimal gland was easily palpable. The patient had restricted infraduction in the OD. MRI showed thickened superior ophthalmic veins on both sides and an enlarged left lacrimal gland. Blood tests showed elevated soluble interleukin-2 receptors. Biopsy of the enlarged lacrimal gland showed numerous epithelioid granuloma and lymphocytic infiltrates consistent with sarcoidosis. No other systemic sarcoidal lesions were detected. The patient started to take prednisolone of 30 mg/day, and the dose was tapered by 5 mg every 2 weeks. At 1 month after taking prednisolone, imaging showed no thickening of the superior ophthalmic veins. At 5 months follow-up, the left lacrimal gland was not palpable, limitation of infraduction improved, and diplopia resolved.

Long-Term Outcome for Primary Papillomas of the Lacrimal Drainage System.

PURPOSE: To report long-term outcomes after surgery for primary benign papillomas of the lacrimal drainage system. METHODS: Retrospective review of patients with primary lacrimal drainage system papillomas, first seen between 1984 and 2021, but excluding lesions with sino-nasal origin or malignant histology. Patients were categorized by tumor histology (squamous, transitional, and mixed cell) and growth pattern (exophytic, endophytic, or mixed). RESULTS: Thirty patients (18 female; 60%) presented at a mean age of 46.1 years (12-79 years). Over an average follow-up of 10.4 years, 30% of patients experienced recurrence, with rates differing slightly by growth pattern: 25% for exophytic tumors and 40% for endophytic and mixed-pattern tumors ( p = 0.431). The overall 5-year recurrence-free survival was 67% (± 9% standard error), this being slightly higher for exophytic lesions (75% ± 10%) as compared to 48% (± 19%) for tumors with an endophytic component ( p = 0.370). No cases of malignant transformation were observed, and the tumor type at recurrence matched the initial diagnosis. CONCLUSION: Primary benign papillomas of the lacrimal drainage system have a long-term recurrence rate of about one-third, with a higher frequency in those exhibiting an endophytic growth pattern. The study highlights the importance of prolonged surveillance for recurrence, especially for endophytic and mixed growth pattern tumors, and for the potential to undergo malignant transformation. The results support the effectiveness of endoscopic surgical excision or laser thermos-ablation in managing recurrent lacrimal drainage system papillomas after dacryocystorhinostomy.

Presumed Lacrimal Gland Pleomorphic Adenoma With Extensive Ossification and Necrosis.

Calcification within pleomorphic adenomas of the lacrimal gland is well recognized but uncommon, being seen more readily in lacrimal gland carcinomas. Bony formation, ossification, in pleomorphic adenomas of the lacrimal glands is even rarer. Together with extensive sclerosis, or "coagulative necrosis," ossification and necrosis should alert the clinician to the risk of malignant transformation. However, both can mimic carcinomatous change, leading to misinterpretation of malignancy in an otherwise benign lacrimal gland neoplasm. We present 2 case reports of patients with clinically presumed pleomorphic adenomas of the lacrimal gland whose histopathology demonstrated lacrimal gland ossification and necrosis without features of malignancy or invasive disease.

Lacrimal Gland Adenocarcinoma Clinicopathologic Features and Outcomes Compared With Those of Lacrimal Gland Adenoid Cystic Carcinoma.

PURPOSE: Lacrimal gland (LG) adenocarcinomas (ACs) are rare, with limited data. We compared clinicopathologic features and local recurrence, distant metastasis, and survival rates between LG AC and LG adenoid cystic carcinoma (ACC). METHODS: The records of LG AC patients treated from 2008 to 2022 and LG ACC patients treated from 1998 to 2022 at the same center were retrospectively reviewed. RESULTS: The study included 20 patients with AC; 10 de-novo AC, 10 ex-pleomorphic AC; and 51 ACC patients. The median age at diagnosis was 61 years for de-novo AC, 54 years for ex-pleomorphic AC, and 45 years for ACC. All groups had male predominance. The initial T category was T2 in 50% (5/10) of de-novo ACs; 60% (6/10) of ex-pleomorphic ACs; and 59% (30/51) of ACCs. Perineural invasion was present in 33% (5/15) of ACs and 90% (45/50) of ACCs ( p < 0.001). Of the 20 AC patients, 14 had eye-sparing surgery; 4 had orbital exenteration; and 2 had unresectable disease. All AC patients received postoperative radiotherapy and 15 (75%) received concurrent chemotherapy. Fourteen AC patients were tested for human growth factor receptor 2 expression, and 10 (71%) were human growth factor receptor 2 positive; 5 received human growth factor receptor 2-targeted therapy. AC and ACC had similar 5-year recurrence rates (20% and 33%, respectively, p = 0.31) and metastasis rates (20% and 34%, respectively, p = 0.30). de-novo AC, ex-pleomorphic AC, and ACC had similar 5-year disease-specific survival rates (80%, 79%, and 81%, respectively, p > 0.99). CONCLUSIONS: LG AC and ACC have similar baseline clinicopathologic features, except that perineural invasion is more common in ACC, and similar recurrence, metastasis, and survival rates. Human growth factor receptor 2-targeted therapy may be appropriate in some patients with LG AC.

Exploring Immune Cell Diversity in the Lacrimal Glands of Healthy Mice: A Single-Cell RNA-Sequencing Atlas.

The lacrimal gland is responsible for maintaining the health of the ocular surface through the production of tears. However, our understanding of the immune system within the lacrimal gland is currently limited. Therefore, in this study, we utilized single-cell RNA sequencing and bioinformatic analysis to identify and analyze immune cells and molecules present in the lacrimal glands of normal mice. A total of 34,891 cells were obtained from the lacrimal glands of mice and classified into 18 distinct cell clusters using Seurat clustering. Within these cell populations, 26 different immune cell subpopulations were identified, including T cells, innate lymphocytes, macrophages, mast cells, dendritic cells, and B cells. Network analysis revealed complex cell-cell interactions between these immune cells, with particularly significant interactions observed among T cells, macrophages, plasma cells, and dendritic cells. Interestingly, T cells were found to be the main source of ligands for the Thy1 signaling pathway, while M2 macrophages were identified as the primary target of this pathway. Moreover, some of these immune cells were validated using immunohistological techniques. Collectively, these findings highlight the abundance and interactions of immune cells and provide valuable insights into the complexity of the lacrimal gland immune system and its relevance to associated diseases.

Exorbital Lacrimal Gland Ablation and Regrafting Induce Inflammation but Not Regeneration or Dry Eye.

The study evaluated the regenerative responses of the lacrimal functional unit (LFU) after lacrimal gland (LG) ablation. The LG of Wistar rats was submitted to G1) partial LG ablation, G2) partial ablation and transplantation of an allogeneic LG, or G3) total LG ablation, (n = 7-10/group). The eye wipe test, slit lamp image, tear flow, and histology were evaluated. RT-PCR analyzed inflammatory and proliferation mediators. The findings were compared to naïve controls after 1 and 2 months (M1 and M2). G3 presented increased corneal sensitivity, and the 3 groups showed corneal neovascularization. Histology revealed changes in the LG and corneal inflammation. In the LG, there was an increase in MMP-9 mRNA of G1 and G2 at M1 and M2, in RUNX-1 at M1 and M2 in G1, in RUNX-3 mRNA at M1 in G1, and at M2 in G2. TNF-α mRNA rose in the corneas of G1 and G2 at M2. There was an increase in the IL-1ß mRNA in the trigeminal ganglion of G1 at M1. Without changes in tear flow or evidence of LG regeneration, LG ablation and grafting are unreliable models for dry eye or LG repair in rats. The surgical manipulation extended inflammation to the LFU.