scholarly journals Modulation of Immune Cell Reactivity with Cis-Binding Siglec Agonist

2020 ◽  
Author(s):  
Corleone Delaveris ◽  
Shannon Chiu ◽  
Nicholas Riley ◽  
Carolyn Bertozzi
Keyword(s):  
Cell Lines ◽  
Microglial Cell ◽  
Immune Cell ◽  
Mapk Signaling ◽  
Age Related Macular Degeneration ◽  
Cell Reactivity ◽  
Age Related ◽  
Sialic Acid Binding ◽  
Inhibitory Signaling ◽  
In Cis

Primary inflammatory pathologies caused by phagocytes lead to numerous debilitating conditions, including chronic pain and blindness due to age-related macular degeneration. Many members of the sialic acid-binding immunoglobulin-like lectin (Siglec) family are immunoinhibitory receptors whose agonism is an attractive approach to for anti-inflammatory therapy. Here, we show that synthetic lipid-conjugated glycopolypeptides can insert into cell membranes and engage Siglec receptors in cis, leading to inhibitory signaling. Specifically, we construct a cis-binding agonist of Siglec-9 and show that it modulates MAPK signaling in reporter cell lines, immortalized macrophage and microglial cell lines, and primary human macrophages. These cis-binding agonists of Siglecs present a new modality for therapeutic suppression of immune cell reactivity.

scholarly journals Modulation of Immune Cell Reactivity with Cis-Binding Siglec Agonist

2020 ◽  
Author(s):  
Corleone Delaveris ◽  
Shannon Chiu ◽  
Nicholas Riley ◽  
Carolyn Bertozzi
Keyword(s):  
Cell Lines ◽  
Microglial Cell ◽  
Immune Cell ◽  
Mapk Signaling ◽  
Age Related Macular Degeneration ◽  
Cell Reactivity ◽  
Age Related ◽  
Sialic Acid Binding ◽  
Inhibitory Signaling ◽  
In Cis

Primary inflammatory pathologies caused by phagocytes lead to numerous debilitating conditions, including chronic pain and blindness due to age-related macular degeneration. Many members of the sialic acid-binding immunoglobulin-like lectin (Siglec) family are immunoinhibitory receptors whose agonism is an attractive approach to for anti-inflammatory therapy. Here, we show that synthetic lipid-conjugated glycopolypeptides can insert into cell membranes and engage Siglec receptors in cis, leading to inhibitory signaling. Specifically, we construct a cis-binding agonist of Siglec-9 and show that it modulates MAPK signaling in reporter cell lines, immortalized macrophage and microglial cell lines, and primary human macrophages. These cis-binding agonists of Siglecs present a new modality for therapeutic suppression of immune cell reactivity.

scholarly journals Modulation of immune cell reactivity with cis-binding Siglec agonists

2021 ◽  
Vol 118 (3) ◽  
pp. e2012408118
Author(s):  
Corleone S. Delaveris ◽  
Shannon H. Chiu ◽  
Nicholas M. Riley ◽  
Carolyn R. Bertozzi
Keyword(s):  
Cell Lines ◽  
Immune Cell ◽  
Mapk Signaling ◽  
Age Related Macular Degeneration ◽  
Mitogen Activated Protein Kinase ◽  
Cell Reactivity ◽  
Antiinflammatory Therapy ◽  
Age Related ◽  
Mitogen Activated Protein ◽  
Inhibitory Signaling

Inflammatory pathologies caused by phagocytes lead to numerous debilitating conditions, including chronic pain and blindness due to age-related macular degeneration. Many members of the sialic acid-binding immunoglobulin-like lectin (Siglec) family are immunoinhibitory receptors whose agonism is an attractive approach for antiinflammatory therapy. Here, we show that synthetic lipid-conjugated glycopolypeptides can insert into cell membranes and engage Siglec receptors in cis, leading to inhibitory signaling. Specifically, we construct a cis-binding agonist of Siglec-9 and show that it modulates mitogen-activated protein kinase (MAPK) signaling in reporter cell lines, immortalized macrophage and microglial cell lines, and primary human macrophages. Thus, these cis-binding agonists of Siglecs present a method for therapeutic suppression of immune cell reactivity.

scholarly journals A High-Throughput Cell-Based Gaussia Luciferase Reporter Assay for Identifying Modulators of Fibulin-3 Secretion

2012 ◽  
Vol 18 (6) ◽  
pp. 647-658 ◽  
Author(s):  
John D. Hulleman ◽  
Steven J. Brown ◽  
Hugh Rosen ◽  
Jeffery W. Kelly
Keyword(s):  
Small Molecules ◽  
Cell Lines ◽  
High Throughput ◽  
Age Related Macular Degeneration ◽  
Luciferase Reporter ◽  
Macular Dystrophy ◽  
Gaussia Luciferase ◽  
Chemical Screening ◽  
Age Related ◽  
Pharmacologically Active

An R345W mutation in fibulin-3 causes its inefficient secretion, increased intracellular steady-state levels, and the macular dystrophy, Malattia Leventinese (ML), a disease similar to age-related macular degeneration. It is unknown whether R345W causes ML through increased intracellular levels, by the secretion of a potentially aggregation-prone protein, or both. To identify small molecules that alter the secretion of fibulin-3, we developed ARPE19 retinal cell lines that inducibly express wild-type (WT) or R345W fibulin-3 fused to an enhanced Gaussia luciferase (eGLuc2). Screening of the Library of Pharmacologically Active Compounds demonstrated that these cell lines and the GLuc assay are suitable for high-throughput chemical screening. Two estrogen-related compounds enhanced fibulin-3 secretion, whereas a diverse series of small molecules reduced fibulin-3 secretion. A counterscreen identified compounds that did not substantially alter the secretion of unfused eGLuc2, demonstrating at least partial selectivity for fibulin-3. A secondary assay using untagged fibulin-3 confirmed that the top three inhibitory compounds reduced R345W fibulin-3 secretion. Interestingly, in untagged fibulin-3 studies, one compound, phorbol 12-myristate 13-acetate, reduced R345W fibulin-3 secretion while minimally enhancing WT fibulin-3 secretion, the desired activity and selectivity we sought for ML. The identified compounds could serve as tools for probing the etiology of fibulin-3–related diseases.

scholarly journals Activated microglia-induced neuroinflammatory cytokines lead to photoreceptor apoptosis in age-related macular degeneration-like mice model

2020 ◽  
Author(s):  
Jing Wu ◽  
Ge Gao ◽  
Fanjun Shi ◽  
Chaoyang Zhang ◽  
Hai Xie ◽  
...  
Keyword(s):  
Macular Degeneration ◽  
Inflammatory Cytokines ◽  
Critical Role ◽  
Amyloid Β ◽  
Mapk Signaling ◽  
Microglia Activation ◽  
Age Related Macular Degeneration ◽  
Mice Model ◽  
Activated Microglia ◽  
Age Related

Abstract Background Age-related macular degeneration (AMD) is mainly characterized by progressive deposits of drusen and photoreceptor apoptosis. Due to amyloid β (Aβ) is the main component of drusen, there is a great possibility that Aβ-induced activated microglia leads to inflammation, and plays a critical role in the pathogenesis of AMD. However, the relationship between activated microglia-mediated neuroinflammatory cytokines and photoreceptor apoptosis still remains unclarified. Results In this study, we demonstrated that subretinal injection of Aβ1−42 induced the microglia activation and increased inflammatory cytokines, gave rise to photoreceptor apoptosis in mice. Our results were verified in vitro by co-culture of Aβ1−42 activated primary microglia and photoreceptor cell line 661W, and we also performed that p38 MAPK signaling pathway was involved in Aβ1−42 induced microglia activation and inflammatory cytokines release. Conclusions Overall, our findings indicated that activated microglia-mediated neuroinflammatory cytokines contributed to photoreceptor apoptosis under the stimulation of Aβ1−42. Moreover, this study will provide a potential preventive and therapeutic approach for AMD treatment.

Impact of non-thermal plasma treatment on MAPK signaling pathways of human immune cell lines

Immunobiology ◽  
2013 ◽  
Vol 218 (10) ◽  
pp. 1248-1255 ◽  
Author(s):  
Lena Bundscherer ◽  
Kristian Wende ◽  
Katja Ottmüller ◽  
Annemarie Barton ◽  
Anke Schmidt ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Signaling Pathways ◽  
Cell Lines ◽  
Thermal Plasma ◽  
Immune Cell ◽  
Mapk Signaling ◽  
Non Thermal Plasma ◽  
Human Immune ◽  
Mapk Signaling Pathways

scholarly journals First Evidence for a Role of Siglec-8 in Breast Cancer

2021 ◽  
Vol 22 (4) ◽  
pp. 2000
Author(s):  
Anna Trebo ◽  
Nina Ditsch ◽  
Tom Degenhardt ◽  
Christina Kuhn ◽  
Martina Rahmeh ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Lines ◽  
Immune Cell ◽  
Estrogen Receptor Status ◽  
Peroxisome Proliferator ◽  
Mucin 1 ◽  
Mcf7 Cells ◽  
Peroxisome Proliferator Activated Receptor ◽  
Sialic Acid Binding

Sialic acid-binding immunoglobulin-like lectins (Siglecs) are involved in various immune cell-mediated diseases. Their role in cancer is poorly investigated, and research focusses on Siglec-expression on immune cells interacting with tumor cells. This study evaluates the role of Siglec-8 in breast cancer (BC). Siglec-8 expression was analyzed immunohistochemically on 235 primary BC cases and was correlated with clinical and pathological parameters and outcome. Cell culture experiments were performed with various BC cell lines. Siglec-8 was expressed in 215 BC cases and expression was lowest in triple-negative BC. It correlated with estrogen receptor-status, grading and the prognostic factors galectin (Gal)-7 and tumor-associated mucin-1 (TA-MUC1). However, Gal-7 and TA-MUC1 were only prognosticators for clinical outcome in the cohort expressing high (Immunoreactivity score IRS > 3) Siglec-8 levels but not in the low-expressing cohort. Siglec-8 knockdown led to a significantly reduced Gal-7 expression in MCF7 cells. All BC cell lines expressed low Siglec-8-levels, that could be elevated in MCF7 by Peroxisome proliferator-activated receptor (PPARγ)-stimulation. This study demonstrates that Siglec-8 is expressed in BC cells and correlates with known clinical and prognostic parameters. It is probably associated with Gal-7 and TA-MUC1 and might be regulated via PPARγ. Further analyses focusing on functional associations will clarify Siglec-8’s eligibility as a possible therapeutic target.

scholarly journals In vitro modeling of the complex retinal condition age-related macular degeneration

2022 ◽  
Author(s):  
Karolina Plössl ◽  
Emily Webster ◽  
Christina Kiel ◽  
Felix Grassmann ◽  
Caroline Brandl ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Stress Response ◽  
Macular Degeneration ◽  
Cell Lines ◽  
Genetic Risk ◽  
Oxidative Stress Response ◽  
Age Related Macular Degeneration ◽  
Nrf2 Pathway ◽  
Age Related

Aim: To model a complex retinal disease such as age-related macular degeneration (AMD) in vitro, we aimed to combine genetic and environmental risk factors in a retinal pigment epithelium (RPE) cell culture model generated via induced pluripotent stem cells (iPSCs) from subjects with an extremely high and an extremely low genetic disease risk. As an external stimulus, we chose defined oxidative stress conditions. Methods: Patients were genotyped for known AMD-associated genetic variants and their individual genetic risk score (GRS) was calculated defining individual iPSC-RPE cell lines which reflect the extreme ends of the genetic risk for AMD. Sodium iodate (NaIO3, SI) was used to induce oxidative stress and cellular responses were followed by analyzing nuclear factor erythroid 2-related factor 2 (NRF2) pathway activation by mRNA and protein expression. Results: We present a collection of eight iPSC-RPE cell lines, with four each harboring an extreme low or an extreme high GRS for AMD. RPE identity was verified structurally and functionally. We found that 24 and 72 h of SI treatment induced a significant upregulation of NRF2 response genes HMOX1 and NQO1, without showing cytotoxic effects or negatively influencing RPE cell integrity. High- vs. low-risk cell lines revealed similar first line defenses in oxidative stress response mediated through the NRF2 pathway. Conclusion: Delineating the NRF2-mediated oxidative stress response was sought in iPSC-RPE cell lines with maximally divergent genetic AMD risk profiles. Under the specific stress conditions chosen, our data indicate that genetic predisposition to AMD may not exert a major influence on the NRF2 signaling pathway.

scholarly journals Expanding Horizons in Complement Analysis and Quality Control

2021 ◽  
Vol 12 ◽  
Author(s):  
Ashley Frazer-Abel ◽  
Michael Kirschfink ◽  
Zoltán Prohászka
Keyword(s):  
Quality Assessment ◽  
Complement System ◽  
Lupus Erythematosus ◽  
Response To Therapy ◽  
Rapid Expansion ◽  
Age Related Macular Degeneration ◽  
Complex Nature ◽  
Cell Reactivity ◽  
Age Related ◽  
Multiple Drugs

Complement not only plays a key role in host microbial defense but also modulates the adaptive immune response through modification of T- and B-cell reactivity. Moreover, a normally functioning complement system participates in hematopoiesis, reproduction, lipid metabolism, and tissue regeneration. Because of its powerful inflammatory potential, multiple regulatory proteins are needed to prevent potential tissue damage. In clinical practice, dysregulation and overactivation of the complement system are major causes of a variety of inflammatory and autoimmune diseases ranging from nephropathies, age-related macular degeneration (AMD), and systemic lupus erythematosus (SLE) to graft rejection, sepsis, and multi-organ failure. The clinical importance is reflected by the recent development of multiple drugs targeting complement with a broad spectrum of indications. The recognition of the role of complement in diverse diseases and the advent of complement therapeutics has increased the number of laboratories and suppliers entering the field. This has highlighted the need for reliable complement testing. The relatively rapid expansion in complement testing has presented challenges for a previously niche field. This is exemplified by the issue of cross-reactivity of complement-directed antibodies and by the challenges of the poor stability of many of the complement analytes. The complex nature of complement testing and increasing clinical demand has been met in the last decade by efforts to improve the standardization among laboratories. Initiated by the IUIS/ICS Committee for the Standardization and Quality Assessment in Complement Measurements 14 rounds of external quality assessment since 2010 resulted in improvements in the consistency of testing across participating institutions, while extending the global reach of the efforts to more than 200 laboratories in 30 countries. Worldwide trends of assay availability, usage, and analytical performance are summarized based on the past years’ experiences. Progress in complement analysis has been facilitated by the quality assessment and standardization efforts that now allow complement testing to provide a comprehensive insight into deficiencies and the activation state of the system. This in turn enables clinicians to better define disease severity, evolution, and response to therapy.

scholarly journals Biomarkers of Neurodegeneration and Precision Therapy in Retinal Disease

2021 ◽  
Vol 11 ◽  
Author(s):  
Alessandra Micera ◽  
Bijorn Omar Balzamino ◽  
Antonio Di Zazzo ◽  
Lucia Dinice ◽  
Stefano Bonini ◽  
...  
Keyword(s):  
Immune Cell ◽  
Current Knowledge ◽  
Age Related Macular Degeneration ◽  
Public Health Issue ◽  
Amyloid Formation ◽  
Retinal Diseases ◽  
Related Factors ◽  
Disease Evolution ◽  
Age Related ◽  
Tissue Aging

Vision-threatening retinal diseases affect millions of people worldwide, representing an important public health issue (high social cost) for both technologically advanced and new-industrialized countries. Overall RD group comprises the retinitis pigmentosa, the age-related macular degeneration (AMD), the diabetic retinopathy (DR), and idiopathic epiretinal membrane formation. Endocrine, metabolic, and even lifestyles risk factors have been reported for these age-linked conditions that represent a “public priority” also in this COVID-19 emergency. Chronic inflammation and neurodegeneration characterize the disease evolution, with a consistent vitreoretinal interface impairment. As the vitreous chamber is significantly involved, the latest diagnostic technologies of imaging (retina) and biomarker detection (vitreous) have provided a huge input at both medical and surgical levels. Complement activation and immune cell recruitment/infiltration as well as detrimental intra/extracellular deposits occur in association with a reactive gliosis. The cell/tissue aging route shows a specific signal path and biomolecular profile characterized by the increased expression of several glial-derived mediators, including angiogenic/angiostatic, neurogenic, and stress-related factors (oxidative stress metabolites, inflammation, and even amyloid formation). The possibility to access vitreous chamber by collecting vitreous reflux during intravitreal injection or obtaining vitreous biopsy during a vitrectomy represents a step forward for an individualized therapy. As drug response and protein signature appear unique in each single patient, therapies should be individualized. This review addresses the current knowledge about biomarkers and pharmacological targets in these vitreoretinal diseases. As vitreous fluids might reflect the early stages of retinal sufferance and/or late stages of neurodegeneration, the possibility to modulate intravitreal levels of growth factors, in combination to anti-VEGF therapy, would open to a personalized therapy of retinal diseases.

scholarly journals NOD-like Receptors in the Eye: Uncovering Its Role in Diabetic Retinopathy

2020 ◽  
Vol 21 (3) ◽  
pp. 899 ◽  
Author(s):  
Rayne R. Lim ◽  
Margaret E. Wieser ◽  
Rama R. Ganga ◽  
Veluchamy A. Barathi ◽  
Rajamani Lakshminarayanan ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Immune Cell ◽  
Early Stage ◽  
Age Related Macular Degeneration ◽  
Therapeutic Interventions ◽  
Diagnostic Tools ◽  
Ocular Infection ◽  
Inflammatory Pathways ◽  
Age Related ◽  
Show Evidence

Diabetic retinopathy (DR) is an ocular complication of diabetes mellitus (DM). International Diabetic Federations (IDF) estimates up to 629 million people with DM by the year 2045 worldwide. Nearly 50% of DM patients will show evidence of diabetic-related eye problems. Therapeutic interventions for DR are limited and mostly involve surgical intervention at the late-stages of the disease. The lack of early-stage diagnostic tools and therapies, especially in DR, demands a better understanding of the biological processes involved in the etiology of disease progression. The recent surge in literature associated with NOD-like receptors (NLRs) has gained massive attraction due to their involvement in mediating the innate immune response and perpetuating inflammatory pathways, a central phenomenon found in the pathogenesis of ocular diseases including DR. The NLR family of receptors are expressed in different eye tissues during pathological conditions suggesting their potential roles in dry eye, ocular infection, retinal ischemia, cataract, glaucoma, age-related macular degeneration (AMD), diabetic macular edema (DME) and DR. Our group is interested in studying the critical early components involved in the immune cell infiltration and inflammatory pathways involved in the progression of DR. Recently, we reported that NLRP3 inflammasome might play a pivotal role in the pathogenesis of DR. This comprehensive review summarizes the findings of NLRs expression in the ocular tissues with special emphasis on its presence in the retinal microglia and DR pathogenesis.

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