Sustentacular Cells Research Articles

MORPHOLOGYOF OLFACTORIORGAN OFCOMMON PALMCIVET (PARADOXURUS HERMAPHRODITUS)

Common Palm Civet (Paradoxurus hermaphroditus) has a very sharp sense of smell that is a tool for selecting ripe and good quality coffee fruit. This research was aimed to study the morphological characteristics of the olfactory organ of Common palm civet macroscopically and microscopically. In this study, three adult Common palm civet were used. Based on macroscopic observations, Common palm civet had olfactory organs consisting of cavum nasi, nostril, septum nasi, conchae and vomeronasale organs found in the nasale. In the dextra and sinistra cavum nasi, there were conchae (superior, medius and inferior). In the medius and inferior conchae, there a respiratory epithelium in the superior conchae, there was the olfactory epithelium. Hematoxylin-Eosin (HE) staining was used for microscopic observation. Based on microscopic observations, the olfactory epithelium composed of sustentacular cells (supporting cells), receptor cells and basal cells. The respiratory epithelium composed of goblet cells, pseudostratified epithelium and basal cells. The vomeronasale epithelium consists of the sensory and non-sensory epithelium. The sensory epithelium covered the ventral two thirds of the medial side of the vomeronasale, while the non-sensory epithelium covered the lateral side and the dorsal thirded of the medial side of the vomeronasale. The epithelium sensory vomeronasale consisted of three types of cells: supporting, receptors, and basal. Non-sensoryepithelium composed of the pseudostratified epithelium and goblet cells

Molecular and Cellular Characterization of the Glutathione Transferases Involved in the Olfactory Metabolism of the Mammary Pheromone.

Odorant metabolizing enzymes, considered as critical olfactory perireceptor actors, control the odor molecules reaching the olfactory epithelium by biotransforming them. As an odorant, the mammary pheromone, i.e., 2-methylbut-2-enal (2MB2), emitted in the milk of lactating female rabbits triggers typical nipple searching-grasping behavior through orocephalic movements in newborn rabbits but not in weaned rabbits. We previously showed that 2MB2 perception is significantly modified when its glutathione transferase-dependent olfactory metabolism is affected in newborns. Here, enzymatic assays of the recombinant enzymes GSTA1, M1, and P1 revealed the activity of these enzymes toward the mammary pheromone. Histological experiments revealed strong expression of the GSTA class restricted to the Bowman glands and of GSTP1 in the nuclei of sustentacular cells. Moreover, some modulations of GSTs have been demonstrated, including a significant increase in GSTP1 expression (2-fold in mRNA, p value < 0.001; protein, p value: 0.031) after 45 min of mammary pheromone exposure at 10-2 g/mL and an increase in GSTA expression in weaned rabbits compared with newborn rabbits (3-fold in mRNA, p value: 0.011; protein, p value: 0.001). Our results provide new insights into the activity, cellular expression, and modulation of the mammary pheromone GST-metabolizing enzymes and clues about their olfactory function.

Aminocarb Exposure Induces Cytotoxicity and Endoplasmic Reticulum Stress-Mediated Apoptosis in Mouse Sustentacular Sertoli Cells: Implications for Male Infertility and Environmental Health.

Exposure to pesticides, poses a significant threat to male fertility by compromising crucial cells involved in spermatogenesis. Aminocarb, is a widely used carbamate insecticide, although its detrimental effects on the male reproductive system, especially on sustentacular Sertoli cells, pivotal for spermatogenesis, remains poorly understood. In this study, we investigated the effects of escalating concentrations of aminocarb on a mouse Sertoli cell line, TM4. Assessments included cytotoxic analysis, mitochondrial biogenesis and membrane potential, expression of apoptotic proteins, caspase-3 activity, and oxidative stress evaluation. Our findings revealed a dose-dependent reduction in the proliferation and viability of TM4 cells following exposure to increasing concentrations of aminocarb. Notably, exposure to 5 μM of aminocarb induced depolarization of mitochondria membrane potential, and a significant decrease in the ratio of phosphorylated eIF2α to total eIF2α, suggesting heightened endoplasmic reticulum stress via the activation of the eIF2α pathway. Moreover, the same aminocarb concentration was demonstrated to increase both caspase-3 protein levels and activity, indicating an apoptotic induction. Collectively, our results demonstrate that aminocarb serves as an apoptotic inducer for mouse sustentacular Sertoli cells in vitro, suggesting its potential to modulate independent pathways of the apoptotic cascade. These findings underscore the deleterious impact of aminocarb on spermatogenic performance and male fertility, highlighting the urgent need for further investigation into its mechanisms of action and mitigation strategies to safeguard male fertility.

A single-cell transcriptomic census of mammalian olfactory epithelium aging.

Mammalian olfactory epithelium has the capacity of self-renewal throughout life. Aging is one of the major causes leading to the olfactory dysfunction. Here, we performed single-cell RNA sequencing (scRNA-seq) analysis on young and aged murine olfactory epithelium (OE) and identified aging-related differentially expressed genes (DEGs) throughout 21 cell types. Aging led to the presence of activated horizontal basal cells (HBCs) in the OE and promoted cellular interaction between HBCs and neutrophils. Aging enhanced the expression of Egr1 and Fos in sustentacular cell differentiation from multipotent progenitors, whereas Bcl11b was downregulated during the sensory neuronal homeostasis in the aged OE. Egr1 and Cebpb were predictive core regulatory factors of the transcriptional network in the OE. Overexpression of Egr1 in aged OE organoids promoted cell proliferation and neuronal differentiation. Moreover, aging altered expression levels and frequencies of olfactory receptors. These findings provide a cellular and molecular framework of OE aging at the single-cell resolution.

Comprehensive Investigation of Angiogenesis, PASS Score and Immunohistochemical Factors in Risk Assessment of Malignancy for Paraganglioma and Pheochromocytoma.

A challenging task in routine practice is finding the distinction between benign and malignant paragangliomas and pheochromocytomas. The aim of this study is to conduct a comparative analysis of angiogenesis by assessing intratumoral microvascular density (MVD) with immunohistochemical (IHC) markers (CD31, CD34, CD105, ERG), and S100 immunoreactivity, Ki67 proliferative index, succinate dehydrogenase B (SDHB) expressiveness, tumor size with one the most utilized score Pheochromocytoma of Adrenal Gland Scales Score (PASS), using tissue microarray (TMA) with 115 tumor samples, 61 benign (PASS < 4) and 54 potentially malignant (PASS ≥ 4). We found no notable difference between intratumoral MVD and potentially malignant behavior. The group of potentially malignant tumors is significantly larger in size, has lower intratumoral MVD, and a decreased number of S100 labeled sustentacular cells. Both groups have low proliferative activity (mean Ki67 is 1.02 and 1.22, respectively). Most tumors maintain SDHB expression, only 6 cases (5.2%) showed a loss of expression (4 of them in PASS < 4 group and 2 in PASS ≥ 4). PASS score is easily available for assessment and complemented with markers of biological behavior to complete the risk stratification algorithm. Size is directly related to PASS score and malignancy. Intratumoral MVD is extensively developed but it is not crucial in evaluating the malignant potential.

Evolution of nasal and olfactory infection characteristics of SARS-CoV-2 variants.

SARS-CoV-2 infection of the upper airway and the subsequent immune response are early, critical factors in COVID-19 pathogenesis. By studying infection of human biopsies in vitro and in a hamster model in vivo, we demonstrated a transition in nasal tropism from olfactory to respiratory epithelium as the virus evolved. Analyzing each variant revealed that SARS-CoV-2 WA1 or Delta infect a proportion of olfactory neurons in addition to the primary target sustentacular cells. The Delta variant possessed broader cellular invasion capacity into the submucosa, while Omicron displayed enhanced nasal respiratory infection and longer retention in the sinonasal epithelium. The olfactory neuronal infection by WA1 and the subsequent olfactory bulb transport via axon were more pronounced in younger hosts. In addition, the observed viral clearance delay and phagocytic dysfunction in aged olfactory mucosa were accompanied by a decline of phagocytosis-related genes. Further, robust basal stem cell activation contributed to neuroepithelial regeneration and restored ACE2 expression postinfection. Together, our study characterized the nasal tropism of SARS-CoV-2 strains, immune clearance, and regeneration after infection. The shifting characteristics of viral infection at the airway portal provide insight into the variability of COVID-19 clinical features, particularly long COVID, and may suggest differing strategies for early local intervention.

ACKR3 in olfactory glia cells shapes the immune defense of the olfactory mucosa.

Barrier-forming olfactory glia cells, termed sustentacular cells, play important roles for immune defense of the olfactory mucosa, for example as entry sites for SARS-CoV-2 and subsequent development of inflammation-induced smell loss. Here we demonstrate that sustentacular cells express ACKR3, a chemokine receptor that functions both as a scavenger of the chemokine CXCL12 and as an activator of alternative signaling pathways. Differential gene expression analysis of bulk RNA sequencing data obtained from WT and ACKR3 conditional knockout mice revealed upregulation of genes involved in immune defense. To map the regulated genes to the different cell types of the olfactory mucosa, we employed biocomputational methods utilizing a single-cell reference atlas. Transcriptome analysis, PCR and immunofluorescence identified up-regulation of NF-κB-related genes, known to amplify inflammatory signaling and to facilitate leukocyte transmigration, in the gliogenic lineage. Accordingly, we found a marked increase in leukocyte-expressed genes and confirmed leukocyte infiltration into the olfactory mucosa. In addition, lack of ACKR3 led to enhanced expression and secretion of early mediators of immune defense by Bowman's glands. As a result, the number of apoptotic cells in the epithelium was decreased. In conclusion, our research underlines the importance of sustentacular cells in immune defense of the olfactory mucosa. Moreover, it identifies ACKR3, a druggable G protein-coupled receptor, as a promising target for modulation of inflammation-associated anosmia.

Mechanisms of COVID-19-associated olfactory dysfunction.

Olfactory dysfunction is one of the most common symptoms of COVID-19. In the first 2 years of the pandemic, it was frequently reported, although its incidence has significantly decreased with the emergence of the Omicron variant, which has since become the dominant viral strain. Nevertheless, many patients continue to suffer from persistent dysosmia and dysgeusia, making COVID-19-associated olfactory dysfunction an ongoing health concern. The proposed pathogenic mechanisms of COVID-19-associated olfactory dysfunction are complex and likely multifactorial. While evidence suggests that infection of sustentacular cells and associated mucosal inflammation may be the culprit of acute, transient smell loss, alterations in other components of the olfactory system (e.g., olfactory receptor neuron dysfunction, olfactory bulb injury and alterations in the olfactory cortex) may lead to persistent, long-term olfactory dysfunction. This review aims to provide a comprehensive summary of the epidemiology, clinical manifestations and current understanding of the pathogenic mechanisms of COVID-19-associated olfactory dysfunction.

Recurrent Wnt Pathway and ARID1A Alterations in Sinonasal Olfactory Carcinoma

Sinonasal tumors with neuroepithelial differentiation, defined by neuroectodermal elements reminiscent of olfactory neuroblastoma (ONB) and epithelial features such as keratin expression or gland formation, are a diagnostically challenging group that has never been formally included in sinonasal tumor classifications. Recently, we documented that most of these neuroepithelial neoplasms have distinctive histologic and immunohistochemical findings and proposed the term “olfactory carcinoma” to describe these tumors. However, the molecular characteristics of olfactory carcinoma have not yet been evaluated. In this study, we performed targeted molecular profiling of 23 sinonasal olfactory carcinomas to further clarify their pathogenesis and classification. All tumors included in this study were composed of high-grade neuroectodermal cells that were positive for pankeratin and at least 1 specific neuroendocrine marker. A significant subset of cases also displayed rosettes and neurofibrillary matrix, intermixed glands with variable cilia, peripheral p63/p40 expression, and S100 protein-positive sustentacular cells. Recurrent oncogenic molecular alterations were identified in 20 tumors, including Wnt pathway alterations affecting CTNNB1 (n = 8) and PPP2R1A (n = 2), ARID1A inactivation (n = 5), RUNX1 mutations (n = 3), and IDH2 hotspot mutations (n = 2). Overall, these findings do demonstrate the presence of recurrent molecular alterations in olfactory carcinoma, although this group of tumors does not appear to be defined by any single mutation. Minimal overlap with alterations previously reported in ONB also adds to histologic and immunohistochemical separation between ONB and olfactory carcinoma. Conversely, these molecular findings enhance the overlap between olfactory carcinoma and sinonasal neuroendocrine carcinomas. A small subset of neuroepithelial tumors might better fit into the superseding molecular category of IDH2-mutant sinonasal carcinoma. At this point, sinonasal neuroendocrine and neuroepithelial tumors may best be regarded as a histologic and molecular spectrum that includes core groups of ONB, olfactory carcinoma, neuroendocrine carcinoma, and IDH2-mutant sinonasal carcinoma.

Intra-adrenal Paraganglioma and Paraaortic Paraganglioma in 15 Years Old Boys

Intra-adrenal paraganglioma (also called pheochromocytoma) is a chromaffin cell tumor that arises in the adrenal medulla and produces excess catecholamines. Paraganglioma can also be located in the extra-adrenal area. The incidence rate of intra-adrenal and extra-adrenal paraganglioma is about 1 case per 2.500-6.500 population, highest incidence at 40-50 years old, and distribution is the same in males and females. Intra-adrenal paraganglioma in pediatrics is more familial, bilateral, multifocal, and malignant. In children, the incidence rate of these tumors was 8.86%, the ratio of boys to girls was 2:1, and the average age of 11. This article reports a case, of a 15 years old boy with severe headaches, recurrent seizures, and a hypertension crisis (143/103-220/110 mmHg). MSCT scan of abdominal showed solid mass heterogeneous with central necrotic multiple in the supero-anterior of the left and right kidneys and on the right anterolateral aorta as high as CV L2, impressive adrenal gland mass and extra-adrenal, suspect pheochromocytoma. Performed surgery, routine histopathological examination, and Immunohistochemistry. Macroscopic examination showed an oval round shape mass of left and right adrenal tumors as well as the paraaortic, a smooth outer surface of the capsular, with yellowish brown color mass tumor at cut surface, supple consistency. Microscopic examination showing adrenal gland and paraaortic tissue with fibrous capsule contains proliferation of neoplastic cells forming a nested alveolar (Zellballen) pattern with a round oval to polygonal cells, granular eosinophilic cytoplasm, round oval nuclei, surrounded by sustentacular cells. Chromogranin A and S-100 are positive. The case was concluded by clinical findings, histopathological, and immunohistochemistry as intra-adrenal paraganglioma and paraganglioma of paraaortic.

Single-cell transcriptome analysis reveals tumoral microenvironment heterogenicity and hypervascularization in human carotid body tumor.

Carotid body tumor (CBT) is a rare neck tumor located at the adventitia of the common carotid artery bifurcation. The prominent pathological features of CBT are high vascularization and abnormal proliferation. However, single-cell transcriptome analysis of the microenvironment composition and molecular complexity in CBT has yet to be performed. In this study, we performed single-cell RNA sequencing (scRNA-seq) analysis on human CBT to define the cells that contribute to hypervascularization and chronic hyperplasia. Unbiased clustering analysis of transcriptional profiles identified 16 distinct cell populations including endothelial cells (ECs), smooth muscle cells (SMCs), neuron cells, macrophage cells, neutrophil cells, and T cells. Within the ECs population, we defined subsets with angiogenic capacity plus clear signs of later endothelial progenitor cells (EPCs) to normal ECs. Two populations of macrophages were detectable in CBT, macrophage1 showed enrichment in hypoxia-inducible factor-1 (HIF-1) and as well as an early EPCs cell-like population expressing CD14 and vascular endothelial growth factor. In addition to HIF-1-related transcriptional protein expression, macrophages1 also display a neovasculogenesis-promoting phenotype. SMCs included threepopulations showing platelet-derived growth factor receptor betaand vimentinexpression, indicative of a cancer-associated fibroblastphenotype. Finally, we identified three types of neuronal cells, including chief cells and sustentacular cells, and elucidated their distinct roles in the pathogenesis of CBT and abnormal proliferation of tumors. Overall, our study provided the first comprehensive characterization of the transcriptional landscape of CBT at scRNA-seq profiles, providing novel insights into the mechanisms underlying its formation.

ADP-mediated Modulation of Intracellular Calcium Responses in Chromaffin Cells: The Role of Ectonucleoside Triphosphate Diphosphohydrolase 2 on Rat Adrenal Medulla Function.

The present study investigated the localization and the adenosine 5'-triphosphate (ATP)-degrading function of the plasma membrane-bound ecto-nucleotidase, ectonucleoside triphosphate diphosphohydrolase 2 (NTPDase2), in the rat adrenal medulla. The effect of ATP degradation product, adenosine 5'-diphosphate (ADP), on carbachol (CCh)-induced intracellular Ca2+ ([Ca2+]i) responses in adrenal chromaffin cells was examined using calcium imaging. NTPDase2-immunoreactive cells were distributed between chromaffin cells. NTPDase2-immunoreactive cells were immunoreactive for glial fibrillary acidic protein and S100B, suggesting that they were sustentacular cells. NTPDase2-immunoreactive cells surrounded chromaffin cells immunoreactive for vesicular nucleotide transporter and P2Y12 ADP-selective purinoceptors. In ATP bioluminescence assays using adrenal medullary slices, ATP was rapidly degraded and its degradation was attenuated by the NTPDase inhibitors sodium polyoxotungstate (POM-1) and 6-N, N-diethyl-d-β,γ-dibromomethylene ATP (ARL67156). ADP inhibited CCh-induced [Ca2+]i increases of chromaffin cells in adrenal medullary slices. The inhibition of CCh-induced [Ca2+]i increases by ADP was blocked by the P2Y12 purinoceptor antagonist AZD1283. CCh-induced [Ca2+]i increases were also inhibited by the P2Y1, P2Y12, and P2Y13 purinoceptor agonist 2-methylthioadenosine diphosphate trisodium (2MeSADP), in combination with the P2Y1 purinoceptor antagonist MRS2179. These results suggest that sustentacular cells express NTPDase2 to degrade ATP released from adrenal chromaffin cells, and ADP modulates the excitability of chromaffin cells via P2Y12 purinoceptors to regulate catecholamine release during preganglionic sympathetic stimuli. (J Histochem Cytochem 72: 41-60, 2024).

Clinicopathological features of olfactory carcinoma

Objective: To investigate the clinicopathological features and differential diagnosis of olfactory carcinoma (OC). Methods: Twenty-one cases of sinonasal tumors, including those initially diagnosed as olfactory neuroblastoma (ONB) and those with uncertain diagnosis, were collected from the Department of Pathology, the First Affiliated Hospital of University of Science and Technology of China (Anhui Provincial Hospital) from January 2016 to August 2022, among which 3 cases were reclassified as OC. The clinicopathological features were investigated, and the remaining 18 cases were used as control. Results: Of the three OC patients, 2 were male and 1 was female, with an average age of 57 years ranging from 35 to 74 years. Microscopically, the tumor cells were arranged in solid, nested or lobulated patterns with occasional palisading around the solid nests. The stroma was highly vascular with focal neurofibrillary areas. There were prominent rosettes or pseudorosettes formation. The tumor cells were mainly ovoid to spindly with scant to moderate amount of cytoplasm, one or several small nucleoli, and fine chromatin content. Brisk mitotic figures were seen. In all 3 cases of OC, there were scanty atypical glands and some were ciliated. Immunohistochemically, at least one epithelial marker and neuroendocrine marker were diffusely expressed in the tumor. Some of the tumor cells were positive for p40 and p63, and the sustentacular cells showed the expression of S-100 protein. All cases tested were negative for NUT, CD99 and desmin, with intact expression of SMARCA4 (BRG1) and SMARCB1 (INI-1). Ki-67 proliferation index varied from 20% to 80%. Follow-up after 16-18 months showed no mortality with tumor recurrence from 1 patient after 16 months. Conclusion: OC is a rare sinonasal tumor with neuroepithelial differentiation, its histomorphology is diverse, and the combination of immunohistochemical markers is essential for appropriate diagnosis.

Histomorphometric study of seminiferous tubules and epididymis in adult ram

This research set out to examine the epididymis and seminiferous tubules of adult male Rams, use both histological and histomorphometric methods. For this purpose, ten paired of testis of healthy adult local rams were taken from local abattoir in Fallujah. Tissue was removed and cut into tiny pieces from different parts of the testicles before being put in Bouin's solution. The tissue samples were processed by common paraffin technique then stained with routine H &amp; E stain as well as Masson's trichrome stain. According to the results of the present histological analysis, the ram's testis is enclosed by a capsule of thick irregular connective tissue, and its lobules are separated by trabecular and interlobular septa, with seminiferous tubules and interstitial tissue making up each lobule. Spermatogenic cells and Sertoli cells border the seminiferous tubules. Spermatozoa develop from spermatogenic cells. Spermatogonia are the earliest stages of spermatogenic cells; they are tiny, spherical cells with black, spherical nuclei that sit on the basement membrane. Primary spermatocytes, which are bigger cells with often-distinct chromatin, are generated during mitosis in the spermotogonia. Because of their rapid second meiotic division and subsequent formation of haploid spermatids, secondary spermatocytes are seldom seen. Clustered near the seminiferous tubule's lumen, the spermatids are spherical cells with pale nuclei. There are less Sertoli cells (sustentacular cells) than spermatogenic cells. The nucleus is oval or triangular in shape and pale in colour, with a large nucleolus. Leydig cells are found in the connective tissue between neighbouring tubules. Epithelium that is pseudostratified lines the epididymis. The stereocilia are long cytoplasmic structures that extend into the lumen. Circular smooth muscle is present in varying amounts, and the epithelium is supported by a connective tissue lamina propria.In conclusion, the current study concluded that the thickness of the epithelium of epididymis was decrease toward the tail while the thickness of the smooth muscle layer was increase toward the tail.

Glia Cells Control Olfactory Neurogenesis by Fine-Tuning CXCL12.

Olfaction depends on lifelong production of sensory neurons from CXCR4 expressing neurogenic stem cells. Signaling by CXCR4 depends on the concentration of CXCL12, CXCR4's principal ligand. Here, we use several genetic models to investigate how regulation of CXCL12 in the olfactory stem cell niche adjusts neurogenesis. We identify subepithelial tissue and sustentacular cells, the olfactory glia, as main CXCL12 sources. Lamina propria-derived CXCL12 accumulates on quiescent gliogenic stem cells via heparan sulfate. Additionally, CXCL12 is secreted within the olfactory epithelium by sustentacular cells. Both sustentacular-cell-derived and lamina propria-derived CXCL12 are required for CXCR4 activation. ACKR3, a high-affinity CXCL12 scavenger, is expressed by mature glial cells and titrates CXCL12. The accurate adjustment of CXCL12 by ACKR3 is critical for CXCR4-dependent proliferation of neuronal stem cells and for proper lineage progression. Overall, these findings establish precise regulation of CXCL12 by glia cells as a prerequisite for CXCR4-dependent neurogenesis and identify ACKR3 as a scavenger influencing tissue homeostasis beyond embryonic development.

Paraganglioma with high-grade intraepithelial neoplasia in the oesophagus treated by endoscopic submucosal dissection.

A 37-year-old woman was hospitalised with a 4-month history of retrosternal pain. Gastroscopy revealed a protrusion lesion of approximately 0.6 cm in diameter in the left wall of the oesophagus, approximately 27 cm from the incisor (Fig. 1). Consequently, one biopsy specimen was taken from the oesophagus. Based on the pathology and immunohistochemistry findings, the patient was initially diagnosed with paraganglioma with high-grade squamous intraepithelial neoplasia. The patient underwent endoscopic submucosal dissection 12 days after the biopsy. The protrusion lesion was again observed under gastroscopy, with visible scarring on the surface (Fig. 2A). A hypoechoic and heterogeneous mass of about 7.1 mm × 2.0 mm in the muscularis mucosae layer was detected on endoscopic ultrasonography (Fig. 2B). The mass was excised after submucosal injection of adrenaline, melphalan, and glycerol fructose injection (Fig. 2C). The postoperative gross specimen was a mucosal tissue measuring 2 cm × 1.8 cm × 0.2 cm, with a bulging mass underneath (Fig. 2D). The results of immunohistochemical analysis were positive for CD56, Syn, CK8/18, LCK, and S-100 and negative for SSTR2 (Fig. 3D, E). Expression of wild-type P53, focal positivity of CgA, and weak positivity of NSE were noted. The Ki-67 labelling index was 1–2%. The diagnosis of paraganglioma with high-grade squamous intraepithelial neoplasia was confirmed based on the histopathology findings (Fig. 3A, B, C). The patient recovered well during the follow-up. Fig. 2(A) The protrusion lesion was found again under gastroscopy, with visible scarring on the surface. (B) Endoscopic ultrasonography detected a hypoechoic and heterogeneous mass of about 7.1 mm × 2.0 mm in the muscularis mucosae layer. (C) Adrenaline, melphalan and glycerol fructose injection was injected in the submucosa after the lesion was marked with a dual knife. (D) Gross specimen after endoscopic submucosal dissection. View Large Image Figure Viewer Download Hi-res image Fig. 3Microscopic examination. (A) Significant cytological atypia in squamous epithelium with continuous basement membrane, and arrangement of the cells in nests (“Zellballen”) in muscularis mucosae. (HE stain × 4) (B) The tumour was composed of chief cells and sustentacular cells. (HE stain × 10) (C) The chief cell is polygonal with a fine granular cytoplasm of acidophilia as well as basophilia. The nucleus is round to elliptical. The sustentacular cells of spindle-shape are distributed around the tumour cell nests or interdigitated amongst the sustentacular cells. (HE stain × 40) (D) positivity of S-100 protein (× 10). (E) positivity of Syn. (× 10). View Large Image Figure Viewer Download Hi-res image

First report of primary testicular leiomyosarcoma in two dogs

BackgroundTesticular tumours are common in dogs and, among them, interstitial cell tumours, seminomas and sustentacular cell tumours are the most reported. Mesenchymal testicular tumours are rarely reported in humans as in veterinary medicine where only three cases of sarcomas (leiomyomas and leomyosarcomas) have been described in two stallions and in a ram.Case presentationThe present cases regarded a 12-year-old mixed-breed dog and a 10-year-old American Staffordshire Terrier that underwent bilateral orchiectomy. Formalin fixed testes were referred for histopathological diagnosis. At gross examination, in one of the testes of both dogs, a white, firm and variably cystic testicular mass, effacing and replacing the testicular parenchyma was detected. Samples were collected from both neoplastic and contralateral testes, routinely processed for histology and serial sections were also examined immunohistochemically with primary antibodies against cytokeratins, vimentin, Von Willebrand factor, inhibin-α, α-smooth muscle actin, smooth muscle myosin and desmin. Histopathological features as well as the immunohistochemical results, positive for vimentin, actin, myosin and desmin, confirmed the mesenchymal origin and the myoid phenotype of both testicular tumours supporting the diagnoses of leiomyosarcoma.ConclusionsTo the authors knowledge these are the first cases of primary testicular sarcoma reported in the canine species. However, even rare, these tumours deserve to be considered in routine diagnosis when a testicular spindle cell tumour is observed. The immunohistochemical panel applied was useful to distinguish the present tumours from undifferentiated Sertoli cell tumours confirming the diagnosis of leiomyosarcoma.

Adamantinoma-like Ewing Sarcoma (ALES) May Harbor FUS Rearrangements : A Potential Diagnostic Pitfall.

Adamantinoma-like Ewing sarcoma (ALES) is a rare malignancy currently considered a variant of Ewing sarcoma with most known cases harboring EWSR1 rearrangements. Herein we present a series of 6 cases of EWSR1 -negative ALES. The tumors arose in the sinonasal tract (n=3), major salivary glands (submandibular gland=1; parotid=1), and anterior mediastinum (n=1) in patients ranging from 25 to 79 years of age. Most tumors were basaloid in appearance, growing in large nests separated by interlobular fibrosis without overt squamous pearls. However, 1 case closely resembled a well-differentiated neuroendocrine tumor with uniformly round nuclei, eosinophilic cytoplasm, and trabecular architecture. All cases were diffusely positive for pan-cytokeratin, p40 or p63, and CD99. A subset of cases showed diffuse reactivity for synaptophysin, including 1 sinonasal tumor which also demonstrated sustentacular S100 protein expression. Molecular testing showed FUS rearrangements in all cases. Gene partners included known ETS family members FEV (n=2) and FLI1 (n=1). Our results expand the molecular diagnostic considerations for ALES to include FUS rearrangements. We also show that ALES may harbor FUS :: FLI1 fusion, which has not been previously reported in the Ewing family of tumors. Furthermore, ALES may show unusual histologic and immunophenotypic features that can overlap with olfactory carcinoma including S100-positive sustentacular cells. ALES should be considered in the diagnostic differential of small round cell tumors and tumors with neuroendocrine differentiation with immunohistochemical workup to include p40 and CD99/NKX2.2.

The immune mechanism of the nasal epithelium in COVID-19-related olfactory dysfunction.

During the first waves of the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, olfactory dysfunction (OD) was reported as a frequent clinical sign. The nasal epithelium is one of the front-line protections against viral infections, and the immune responses of the nasal mucosa may be associated with OD. Two mechanisms underlying OD occurrence in COVID-19 have been proposed: the infection of sustentacular cells and the inflammatory reaction of the nasal epithelium. The former triggers OD and the latter likely prolongs OD. These two alternative mechanisms may act in parallel; the infection of sustentacular cells is more important for OD occurrence because sustentacular cells are more likely to be the entry point of SARS-CoV-2 than olfactory neurons and more susceptible to early injury. Furthermore, sustentacular cells abundantly express transmembrane protease, serine 2 (TMPRSS2) and play a major role in the olfactory epithelium. OD occurrence in COVID-19 has revealed crucial roles of sustentacular cells. This review aims to elucidate how immune responses of the nasal epithelium contribute to COVID-19-related OD. Understanding the underlying immune mechanisms of the nasal epithelium in OD may aid in the development of improved medical treatments for COVID-19-related OD.

Gallbladder Paraganglioma- A Rare Case Report

A 34-years-old married middle-class housewife without diabetes, hypertension or betel-nut- chewing hailing from Manikganj, Dhaka; came with the outside diagnosis as neuroendocrine tumor of the gallbladder to the Oncology Department of Khwaja Yunus Ali Medical College and Hospital (KYAMCH). She was admitted in the hospital with complaints of upper abdominal pain, abdominal bloating, weakness, anorexia, nausea and heartburn while taking fatty food. According to her Ultrasonography (USG) of the abdomen, a soft tissue mass was found in the gallbladder with unremarkable routine blood examination including tumor markers. She underwent open cholecystectomy with the suspicion of cancer. Grossly, gallbladder was measures 7.0x 5.0 cm with 0.3 cm wall thickness and on opening a polypoid nodule is found. Before treatment on request from the Oncology Department of KYAMCH, all slides were reviewed and a histopathological diagnosis of paraganglioma was made on the basis of organoid, nested or lobules (Zellballen pattern) of tumor cells in the lamina propria surrounded by a prominent fibrovascular stroma. Atypical mitoses, tumor necrosis, lymphovascular or perineural invasion was not found. The IHC reveals diffuse and strong positive reactions to NSE and CD56 for chief cells and strong positive reaction to S-100 protein for sustentacular cells. The epithelial tumor was ruled out by CK negative reaction. Therefore, the diagnosis of paraganglioma of the gallbladder was established. Because of the positive reaction to sustentacular cells, the neuroendocrine tumor has been excluded. To our knowledge, this type of case has not been reported in our country. On clinical follow-up the patient was found healthy. KYAMC Journal Vol. 14, No. 01, April 2023: 57-61