CMTM6: Increased Circulating Level and Up-regulated Expression in Labial Salivary Glands in Patients with Primary Sjogren’s Syndrome

Chemokine-like factor (CKLF)-like MARVEL transmembrane domain containing family member 6 (CMTM6), which is a key regulator of programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) signaling in patients with primary Sjögren’s syndrome (pSS). In the present paper, we analysed the serum levels of CMTM6, PD-1 and PD-L1 in 50 patients with pSS, 42 patients with non-pSS (simply dry mouth and/or eyes symptoms) and 50 healthy controls (HC). The expression of CMTM6, PD-1 and PD-L1 in labial glands of the same 50 pSS patients and 42 non-pSS patients were assessed by immunohistochemistry (IHC). The clinical significance of CMTM6, PD-1 and PD-L1 were analyzed. We found that levels of CMTM6, PD-L1 as well as PD-1 in sera were all increased significantly in patients with pSS compared with non-pSS controls and HC. Serum CMTM6 level showed significantly correlation with PD-L1, PD-1, as well as clinical laboratory indicators and disease activity of pSS patients. CMTM6, PD-1 and PD-L1 expression in labial glands was also higher significantly in pSS patients than non-pSS controls. pSS patients with higher CM grade or ESSDAI score have higher CMTM6, PD-L1 and PD-1expression in labial glands. These results suggests that CMTM6 may affect peripheral tolerance and lymphocytes activation by PD-1/PD-L1 pathway in sera and target tissue in pSS.

The Transcriptome of Paired Major and Minor Salivary Gland Tissue in Patients With Primary Sjögren’s Syndrome

BackgroundWhile all salivary glands (SGs) can be involved in primary Sjögren’s syndrome (pSS), their respective role in pathogenesis remains unclear. Our objective was to assess immunopathway activation in paired parotid and labial gland tissue from biopsy-positive and biopsy-negative pSS and non-SS sicca patients.MethodsParaffin-embedded, paired parotid and labial salivary gland tissue and peripheral blood mononuclear cells were obtained from 39 pSS and 20 non-SS sicca patients. RNA was extracted, complementary DNA libraries were prepared and sequenced. For analysis of differentially expressed genes (DEGs), patients were subdivided based on fulfillment of ACR-EULAR criteria and histopathology.ResultsWith principal component analysis, only biopsy-positive pSS could be separated from non-SS sicca patients based on SG gene expression. When comparing the transcriptome of biopsy-positive pSS and biopsy-negative non-SS sicca patients, 1235 and 624 DEGs (FDR<0.05, log2FC<-1 or >1) were identified for parotid and labial glands, respectively. The number of DEGs between biopsy-negative pSS and non-SS sicca patients was scarce. Overall, transcript expression levels correlated strongly between parotid and labial glands (R2 = 0.86, p-value<0.0001). Gene signatures present in both glands of biopsy-positive pSS patients included IFN-α signaling, IL-12/IL-18 signaling, CD3/CD28 T-cell activation, CD40 signaling in B-cells, DN2 B-cells, and FcRL4+ B-cells. Signature scores varied considerably amongst pSS patients.ConclusionTranscriptomes of paired major and minor SGs in pSS were overall comparable, although significant inter-individual heterogeneity in immunopathway activation existed. The SG transcriptome of biopsy-negative pSS was indistinguishable from non-SS sicca patients. Different patterns of SG immunopathway activation in pSS argue for personalized treatment approaches.

High frequency ultrasound assessment of labial glands simulating small nodules or granulomas after lip augmentation

Aim of the study: The aim of this study is to evaluate the utility of high-frequency ultrasound in the assessment of the nature and differentiation of lumps occurring in the labial mucosa after lip filling procedures. Material and methods: The study sample included 5 women aged from 28 to 43 years (mean age: 37.4 years) who previously underwent a lip augmentation or rejuvenation procedure. Photographic documentation was taken and high-frequency ultrasound assessment was performed in all the patients. The presence of deposits, foreign body granulomas, fibrosis and labial glands was mainly investigated taking into account the shape of the abnormalities, their margins, surface area, location and echogenicity. In order to confirm the diagnosis, histopathological examination was performed. Results: The examinations performed made it possible to differentiate between granulomas and persistent deposit nodules and to demonstrate the presence of massive fibrosis and of labial glands pushed out by these abnormalities with the glands presenting as hypoechoic oval areas. Histopathological examination confirmed the morphology of labial glands reported by the patients as uncomfortable lumps felt from the side of the mucosa, which clinically simulate persistent deposit nodules or granulomas. Conclusions: High-frequency ultrasound is a method that is essential for the correct differentiation between complications of tissue filler procedures. This, in turn, makes it possible to apply the right treatment. In this study, it was demonstrated for the first time that the lumps reported by patients who have had a lip filling procedure may be the result of labial glands being pushed out by deposits, granulomas or massive fibrosis, which are complications of such procedures.

Labial Stem Cell Extract Mitigates Injury to Irradiated Salivary Glands

Stem cell–based therapies could provide a permanent treatment for salivary gland (SG) hypofunction caused by ionizing radiation (IR) injury. However, current challenges for SG stem cells to reach the clinic include surgical invasiveness, amount of tissue needed, cell delivery, and storage methods. The objective of this study was to develop a clinically less invasive method to isolate and expand human SG stem cells and then to obtain a cell-free extract to be used as a therapy for IR-injured SGs. Human labial glands were biopsied, and labial stem cells (LSCs) were expanded by explant culture. The LSC extract (LSCE) was obtained by releasing the cellular components after 3 freeze-thaw cycles and 17,000 g force centrifugation. LSCE was injected intravenously into mice that had their SGs injured with 13-Gy IR. Positive (non-IR) and negative (IR) control mice received injections of saline (vehicle control). Three pieces of labial glands (0.1 g weight) could expand 1 to 2 million cells. LSCs had a doubling time of 18.8 h; could differentiate into osteocytes, adipocytes, and chondrocytes; and were positive for mesenchymal stem cell markers. Both angiogenic (FGF-1, FGF-2, KGF, angiopoietin, uPA, VEGF) and antiangiogenic factors (PAI-1, TIMP-1, TSP-1, CD26) were detected in LSCE. In addition, some angiogenic factors (PEDF, PTX3, VEGF) possessed neurotrophic functions. Mice treated with LSCE had 50% to 60% higher salivary flow rate than saline-treated mice at 8 and 12 wk post-IR. Saliva lag time measurements also confirmed that LSCE restored SG function. Histologic analyses of parotids and submandibular glands reported comparable numbers of acinar cells, blood vessels, and parasympathetic nerves and cell proliferation rates in sham IR and LSCE-treated mice, though significantly lower in saline-treated mice. An explant culture method can harvest a large number of LSCs from small pieces of labial glands. LSCE showed clinical potential to mitigate IR-injured SGs.

From Spinning Silk to Spreading Saliva: Mouthpart Remodeling in Manduca sexta (Lepidoptera: Sphingidae)

As a model organism, the tobacco hornworm Manduca sexta (Linnaeus 1763) has contributed much to our knowledge of developmental processes in insects, and major developmental changes between different larval instars are generally well understood. Second and later instars of M. sexta do not produce silk, and their spinneret and accessory labial glands (=Lyonet’s glands), structures thought to be key players in silk production in other lepidopterans, are highly reduced. To our knowledge, mouthparts and labial gland morphology of the silk-producing first instar have never been described. In this study, we compared the mouthpart morphology and transcriptome profile of first and later instars of M. sexta to determine whether the loss of silk production correlates with changes in the structure of the spinneret and the labial glands, and with changes in expression of silk-related genes. We found that the first instar, unlike later instars, has a typical, silk-producing spinneret with a tube-like spigot and well developed Lyonet’s glands. Moreover, three known silk protein genes are highly expressed in the first instar but exhibit little to no expression in the embryo or later instars. Thus, the changes in morphology and gene expression presented here, coinciding with changes in larval behavior from silk production to saliva spreading, further our understanding of the developmental processes underlying this transition in this model organism.

Immunolocalization of Surfactant Proteins SP-A, SP-B, SP-C, and SP-D in Infantile Labial Glands and Mucosa

Surfactant proteins in different glandular structures of the oral cavity display antimicrobial activity for protection of invading microorganisms. Moreover, they are involved in lowering liquid tension in fluids and facilitate secretion flows. Numerous investigations for studying the occurrence of surfactant proteins in glandular tissues were performed using different methods. In the oral cavity, minor salivary glands secrete saliva continuously for the maintenance of a healthy oral environment. For the first time, we could show that infantile labial glands show expression of the surfactant proteins (SP) SP-A, SP-B, SP-C, and SP-D in acinar cells and the duct system in different intensities. The stratified squamous epithelium of the oral mucosa revealed positive staining for SPs in various cell layers.