A Low-Cost Open Source Device for Cell Microencapsulation

Microencapsulation is a widely studied cell therapy and tissue bioengineering technique, since it is capable of creating an immune-privileged site, protecting encapsulated cells from the host immune system. Several polymers have been tested, but sodium alginate is in widespread use for cell encapsulation applications, due to its low toxicity and easy manipulation. Different cell encapsulation methods have been described in the literature using pressure differences or electrostatic changes with high cost commercial devices (about 30,000 US dollars). Herein, a low-cost device (about 100 US dollars) that can be created by commercial syringes or 3D printer devices has been developed. The capsules, whose diameter is around 500 µm and can decrease or increase according to the pressure applied to the system, is able to maintain cells viable and functional. The hydrogel porosity of the capsule indicates that the immune system is not capable of destroying host cells, demonstrating that new studies can be developed for cell therapy at low cost with microencapsulation production. This device may aid pre-clinical and clinical projects in low- and middle-income countries and is lined up with open source equipment devices.

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Leishmania donovani Secretory Mevalonate Kinase Regulates Host Immune Response and Facilitates Phagocytosis

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.641985 ◽

2021 ◽

Vol 11 ◽

Author(s):

Tanvir Bamra ◽

Taj Shafi ◽

Sushmita Das ◽

Manjay Kumar ◽

Manas Ranjan Dikhit ◽

...

Keyword(s):

Immune Response ◽

Immune System ◽

Leishmania Donovani ◽

Indian Subcontinent ◽

Parasite Burden ◽

Host Immune Response ◽

Host Cells ◽

Interleukin 4 ◽

Host Immune System ◽

Mevalonate Kinase

Summary StatementLeishmania secretes over 151 proteins during in vitro cultivation. Cellular functions of one such novel protein: mevalonate kinase is discussed here; signifying its importance in Leishmania infection.Visceral Leishmaniasis is a persistent infection, caused by Leishmania donovani in Indian subcontinent. This persistence is partly due to phagocytosis and evasion of host immune response. The underlying mechanism involves secretory proteins of Leishmania parasite; however, related studies are meagre. We have identified a novel secretory Leishmania donovani glycoprotein, Mevalonate kinase (MVK), and shown its importance in parasite internalization and immuno-modulation. In our studies, MVK was found to be secreted maximum after 1 h temperature stress at 37°C. Its secretion was increased by 6.5-fold in phagolysosome-like condition (pH ~5.5, 37°C) than at pH ~7.4 and 25°C. Treatment with MVK modulated host immune system by inducing interleukin-10 and interleukin-4 secretion, suppressing host’s ability to kill the parasite. Peripheral blood mononuclear cell (PBMC)-derived macrophages infected with mevalonate kinase-overexpressing parasites showed an increase in intracellular parasite burden in comparison to infection with vector control parasites. Mechanism behind the increase in phagocytosis and immunosuppression was found to be phosphorylation of mitogen-activated protein (MAP) kinase pathway protein, Extracellular signal-regulated kinases-1/2, and actin scaffold protein, cortactin. Thus, we conclude that Leishmania donovani Mevalonate kinase aids in parasite engulfment and subvert the immune system by interfering with signal transduction pathways in host cells, which causes suppression of the protective response and facilitates their persistence in the host. Our work elucidates the involvement of Leishmania in the process of phagocytosis which is thought to be dependent largely on macrophages and contributes towards better understanding of host pathogen interactions.

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QTL Mapping of Intestinal Neutrophil Variation in Threespine Stickleback Reveals Possible Gene Targets Connecting Intestinal Inflammation and Systemic Health

G3 Genes|Genome|Genetics ◽

10.1534/g3.119.400685 ◽

2019 ◽

Vol 10 (2) ◽

pp. 613-622

Author(s):

Emily A. Beck ◽

Mark C. Currey ◽

Clayton M. Small ◽

William A. Cresko

Keyword(s):

Immune System ◽

Inflammatory Response ◽

Intestinal Inflammation ◽

Threespine Stickleback ◽

Microbial Interactions ◽

Host Cells ◽

Host Immune System ◽

Complex Genetics ◽

Disease States ◽

Host Genetic

Selection, via host immunity, is often required to foster beneficial microbial symbionts and suppress deleterious pathogens. In animals, the host immune system is at the center of this relationship. Failed host immune system-microbial interactions can result in a persistent inflammatory response in which the immune system indiscriminately attacks resident microbes, and at times the host cells themselves, leading to diseases such as Ulcerative Colitis, Crohn’s Disease, and Psoriasis. Host genetic variation has been linked to both microbiome diversity and to severity of such inflammatory disease states in humans. However, the microbiome and inflammatory states manifest as quantitative traits, which encompass many genes interacting with one another and the environment. The mechanistic relationships among all of these interacting components are still not clear. Developing natural genetic models of host-microbe interactions is therefore fundamental to understanding the complex genetics of these and other diseases. Threespine stickleback (Gasterosteus aculeatus) fish are a tractable model for attacking this problem because of abundant population-level genetic and phenotypic variation in the gut inflammatory response. Previous work in our laboratory identified genetically divergent stickleback populations exhibiting differences in intestinal neutrophil activity. We took advantage of this diversity to genetically map variation in an emblematic element of gut inflammation - intestinal neutrophil recruitment - using an F2-intercross mapping framework. We identified two regions of the genome associated with increased intestinal inflammation containing several promising candidate genes. Within these regions we found candidates in the Coagulation/Complement System, NFkB and MAPK pathways along with several genes associated with intestinal diseases and neurological diseases commonly accompanying intestinal inflammation as a secondary symptom. These findings highlight the utility of using naturally genetically diverse ‘evolutionary mutant models’ such as threespine stickleback to better understand interactions among host genetic diversity and microbiome variation in health and disease states.

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Glycans in Virus-Host Interactions: A Structural Perspective

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.666756 ◽

2021 ◽

Vol 8 ◽

Author(s):

Nathaniel L. Miller ◽

Thomas Clark ◽

Rahul Raman ◽

Ram Sasisekharan

Keyword(s):

Immune System ◽

Host Cells ◽

Host Immune System ◽

Host Interactions ◽

Viral Glycoproteins ◽

Microbe Interactions ◽

Host Microbe Interactions ◽

Anti Hiv ◽

Structural Perspective

Many interactions between microbes and their hosts are driven or influenced by glycans, whose heterogeneous and difficult to characterize structures have led to an underappreciation of their role in these interactions compared to protein-based interactions. Glycans decorate microbe glycoproteins to enhance attachment and fusion to host cells, provide stability, and evade the host immune system. Yet, the host immune system may also target these glycans as glycoepitopes. In this review, we provide a structural perspective on the role of glycans in host-microbe interactions, focusing primarily on viral glycoproteins and their interactions with host adaptive immunity. In particular, we discuss a class of topological glycoepitopes and their interactions with topological mAbs, using the anti-HIV mAb 2G12 as the archetypical example. We further offer our view that structure-based glycan targeting strategies are ready for application to viruses beyond HIV, and present our perspective on future development in this area.

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Low-cost, easy-to-build noninvasive pressure support ventilator for under-resourced regions: open source hardware description, performance and feasibility testing

European Respiratory Journal ◽

10.1183/13993003.00846-2020 ◽

2020 ◽

Vol 55 (6) ◽

pp. 2000846 ◽

Cited By ~ 8

Author(s):

Onintza Garmendia ◽

Miguel A. Rodríguez-Lazaro ◽

Jorge Otero ◽

Phuong Phan ◽

Alexandrina Stoyanova ◽

...

Keyword(s):

Open Source ◽

Low Cost ◽

Bench Test ◽

Mechanical Ventilators ◽

Middle Income ◽

Low Middle Income Countries ◽

Number Of Patients ◽

Hardware Description ◽

Commercial Device ◽

Open Source Hardware

AimCurrent pricing of commercial mechanical ventilators in low-/middle-income countries (LMICs) markedly restricts their availability, and consequently a considerable number of patients with acute/chronic respiratory failure cannot be adequately treated. Our aim was to design and test an affordable and easy-to-build noninvasive bilevel pressure ventilator to allow a reduction in the serious shortage of ventilators in LMICs.MethodsThe ventilator was built using off-the-shelf materials available via e-commerce and was based on a high-pressure blower, two pressure transducers and an Arduino Nano controller with a digital display (total retail cost <75 USD), with construction details provided open source for free replication. The ventilator was evaluated, and compared with a commercially available device (Lumis 150 ventilator; Resmed, San Diego, CA, USA): 1) in the bench setting using an actively breathing patient simulator mimicking a range of obstructive/restrictive diseases; and b) in 12 healthy volunteers wearing high airway resistance and thoracic/abdominal bands to mimic obstructive/restrictive patients.ResultsThe designed ventilator provided inspiratory/expiratory pressures up to 20/10 cmH2O, respectively, with no faulty triggering or cycling; both in the bench test and in volunteers. The breathing difficulty score rated (1–10 scale) by the loaded breathing subjects was significantly (p<0.005) decreased from 5.45±1.68 without support to 2.83±1.66 when using the prototype ventilator, which showed no difference with the commercial device (2.80±1.48; p=1.000).ConclusionThe low-cost, easy-to-build noninvasive ventilator performs similarly to a high-quality commercial device, with its open-source hardware description, which will allow for free replication and use in LMICs, facilitating application of this life-saving therapy to patients who otherwise could not be treated.

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Bases for the Adequate Development of Nutritional Recommendations for Patients with Inflammatory Bowel Disease

Nutrients ◽

10.3390/nu11051062 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1062 ◽

Cited By ~ 4

Author(s):

Esteban Sáez-González ◽

Beatriz Mateos ◽

Pedro López-Muñoz ◽

Marisa Iborra ◽

Inés Moret ◽

...

Keyword(s):

Inflammatory Bowel Disease ◽

Immune System ◽

Environmental Factors ◽

Intestinal Microbiota ◽

Bowel Disease ◽

Nutritional Intervention ◽

Host Cells ◽

Host Immune System ◽

Intestinal Immunity ◽

Inflammatory Bowel

Inflammatory bowel disease (IBD) is a chronic and relapsing inflammatory condition of the gastrointestinal tract; it is a heterogeneous and multifactorial disorder resulting from a complex interplay between genetic variation, intestinal microbiota, the host immune system and environmental factors such as diet, drugs, breastfeeding and smoking. The interactions between dietary nutrients and intestinal immunity are complex. There is a compelling argument for environmental factors such as diet playing a role in the cause and course of IBD, given that three important factors in the pathogenesis of IBD can be modulated and controlled by diet: intestinal microbiota, the immune system and epithelial barrier function. The aim of this review is to summarize the epidemiological findings regarding diet and to focus on the effects that nutrients exert on the intestinal mucosa–microbiota–permeability interaction. The nature of these interactions in IBD is influenced by alterations in the nutritional metabolism of the gut microbiota and host cells that can influence the outcome of nutritional intervention. A better understanding of diet–host–microbiota interactions is essential for unravelling the complex molecular basis of epigenetic, genetic and environmental interactions underlying IBD pathogenesis as well as for offering new therapeutic approaches for the treatment of IBD.

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COVID-19 Vaccines and Dentistry

Dental Update ◽

10.12968/denu.2021.48.1.76 ◽

2021 ◽

Vol 48 (1) ◽

pp. 76-81

Author(s):

Lakshman Samaranayake ◽

Kausar Sadia Fakhruddin

Keyword(s):

Decision Making ◽

Immune System ◽

Antibody Response ◽

Viral Proteins ◽

Host Cells ◽

Bad News ◽

Host Immune System ◽

Dental Practice ◽

The Impact ◽

Gift Wrapping

Transplant pioneer, Peter Medawar, once said that a virus is ‘simply a piece of bad news wrapped in protein’. One could opine then, that the new COVID-19 vaccines are ‘Bits of corona viral proteins in gift wrapping.’ For, most of the COVID-19 vaccines are based on the principle that pre-exposure of the vaccinee's host immune system to the spike proteins of SARS-CoV-2, the first part of the viral anatomy that touches the vulnerable host cells, will elicit an effective antibody response to curb potential future infections. COVID-19 vaccines come in many sizes and shapes, and clearly, a return to normal, post-COVID dental practice entails protecting all members of the dental team with an appropriate vaccine, as and when available. We provide a thumbnail sketch of the COVID-19 vaccines currently in the offing, which we hope will be helpful for decision-making for choice of vaccine. The commentary ends with a discussion of the impact of COVID-19 vaccines on dentistry, in general.

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Guanylate-Binding Protein 1 Inhibits Nuclear Delivery of Kaposi's Sarcoma-Associated Herpesvirus Virions by Disrupting Formation of Actin Filament

Journal of Virology ◽

10.1128/jvi.00632-17 ◽

2017 ◽

Vol 91 (16) ◽

Cited By ~ 11

Author(s):

Zhe Zou ◽

Zhihua Meng ◽

Chao Ma ◽

Deguang Liang ◽

Rui Sun ◽

...

Keyword(s):

Immune System ◽

Actin Filaments ◽

Primary Infection ◽

Rna Viruses ◽

Critical Role ◽

Host Cells ◽

Host Immune System ◽

Kshv Infection ◽

Guanylate Binding Protein

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) is a typical gammaherpesvirus that establishes persistent lifelong infection in host cells. In order to establish successful infection, KSHV has evolved numerous immune evasion strategies to bypass or hijack the host immune system. However, host cells still produce immune cytokines abundantly during primary KSHV infection. Whether the immune effectors produced are able to inhibit viral infection and how KSHV successfully conquers these immune effectors remain largely unknown. The guanylate-binding protein 1 (GBP1) gene is an interferon-stimulated gene and exerts antiviral functions on several RNA viruses; however, its function in DNA virus infection is less well understood. In this study, we found that KSHV infection increases both the transcriptional and protein levels of GBP1 at the early stage of primary infection by activating the NF-κB pathway. The overexpression of GBP1 significantly inhibited KSHV infection, while the knockdown of GBP1 promoted KSHV infection. The GTPase activity and dimerization of GBP1 were demonstrated to be responsible for its anti-KSHV activity. Furthermore, we found that GBP1 inhibited the nuclear delivery of KSHV virions by disrupting the formation of actin filaments. Finally, we demonstrated that replication and transcription activator (RTA) promotes the degradation of GBP1 through a proteasome pathway. Taken together, these results provide a new understanding of the antiviral mechanism of GBP1, which possesses potent anti-KSHV activity, and suggest the critical role of RTA in the evasion of the innate immune response during primary infection by KSHV. IMPORTANCE GBP1 can be induced by various cytokines and exerts antiviral activities against several RNA viruses. Our study demonstrated that GBP1 can exert anti-KSHV function by inhibiting the nuclear delivery of KSHV virions via the disruption of actin filaments. Moreover, we found that KSHV RTA can promote the degradation of GBP1 through a proteasome-mediated pathway. Taken together, our results elucidate a novel mechanism of GBP1 anti-KSHV activity and emphasize the critical role of RTA in KSHV evasion of the host immune system during primary infection.

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Multifaceted Role of the Transforming Growth Factor β on Effector T Cells and the Implication for CAR-T Cell Therapy

Immuno ◽

10.3390/immuno1030010 ◽

2021 ◽

Vol 1 (3) ◽

pp. 160-173

Author(s):

Apolline de Folmont ◽

Jean-Henri Bourhis ◽

Salem Chouaib ◽

Stéphane Terry

Keyword(s):

T Cells ◽

Immune System ◽

T Cell ◽

Cell Therapy ◽

Host Immune System ◽

T Cell Therapy ◽

Car T Cells ◽

Car T Cell ◽

Car T Cell Therapy ◽

Car T

Evading the immune system is one of the hallmarks of cancer. Tumors escape anti-tumor immunity through cell-intrinsic means and the assembly of an immunosuppressive tumor microenvironment. By significantly boosting the host immune system, cancer immunotherapies targeting immune checkpoint receptors (CTLA-4 and PD-1) improved survival in patients even with cancers previously considered rapidly fatal. Nevertheless, an important group of patients is refractory or relapse rapidly. The factors involved in the heterogeneous responses observed are still poorly understood. Other immunotherapeutic approaches are being developed that may widen the options, including adoptive cell therapy using CAR-T cells alone or in combination. Despite impressive results in B cell malignancies, many caveats and unanswered questions remain in other cancers, thus limiting the potential of this approach to treat aggressive diseases. In particular, a complex TME could impair the survival, proliferation, and effector functions of CAR-T cells. Recent reports highlight the potential of targeting TGF-β signaling to improve CAR-T cell therapy. TGF-β is a well-known regulatory cytokine with pleiotropic effects in the TME, including immunosuppression. This review summarizes recent work investigating the potential effects of TGF-β within the TME, with a focus on CAR-T behavior and efficacy. We also discuss several key questions to be addressed to accelerate clinical translation of this approach.

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Investigation of Bartonella quintana Host Immune Evasion

10.26686/wgtn.17131799.v1 ◽

2021 ◽

Author(s):

◽

Callum Lambert

Keyword(s):

Immune System ◽

Actin Cytoskeleton ◽

Host Cell ◽

Immune Evasion ◽

Mammalian Species ◽

Effector Proteins ◽

Host Cells ◽

Sand Fly ◽

Host Immune System ◽

Bartonella Quintana

<p>Bartonella is a genus of gram-negative alphaproteobacteria that infect mammals, causing both acute and chronic disease. Bartonella are re-emerging infectious pathogens that cause a variety of clinical syndromes in humans worldwide, including cat scratch disease, trench fever, bacillary angiomatosis, and endocarditis. Bartonella spp. are spread by biting arthropods such as the sand fly, cat flea, and body louse, and have been isolated from almost all mammalian species tested. Bartonella are a re-emerging concern as the number of confirmed Bartonella diagnoses are increasing, primarily in immunocompromised groups, homeless populations, refugee camps, and in veterinary workers. The three primary human disease-causing Bartonella spp. are B. henselae, B. quintana, and B. bacilliformis. Bartonella are known to subvert the host immune system and persist within the host, often causing bacteraemia which is difficult to effectively diagnose and treat. B. quintana infects humans; after introduction to the skin the bacteria implement numerous immune evasion mechanisms to enter the bloodstream and invade erythrocytes. The mechanisms by which B. quintana modulates and evades the immune system during early infection are almost entirely unknown. Following exposure to B. quintana, the bacteria encounter host immune cells but survive, evading these cells and disseminating into the lymphatic system and eventually bloodstream. This thesis project aimed to dissect the interactions between B. quintana and the human innate immune system to better understand the early stages of infection. A gentamicin protection assay was developed to investigate the ability of THP-1 macrophages, representing human macrophages present in the skin, to internalise B. quintana. These data revealed THP-1 cells were unable to effectively internalise B. quintana, although the mechanism responsible was not determined. Subsequent experiments investigated the role of the B. quintana Type IV secreted effector protein BepA1 in the inhibition of internalisation. Bacterial effector proteins often pathogenically modulate host cell signalling to benefit the bacteria, i.e., altering the actin cytoskeleton to inhibit phagocytosis or supressing immune responses. It was hypothesised BepA1 could play a role in inhibiting phagocytosis; therefore, the host cell target of BepA1 was investigated with a yeast two-hybrid system assay. The human protein Myozap was uncovered as a potential protein that interacts with BepA1. Myozap is expressed in cardiac and lung tissue as well as epithelial and endothelial cells, where it modulates Rho-dependent actin signalling, potentially affecting the actin cytoskeleton and the transcription factor MRTF-A, which influences immune reaction through modulation of NF-κB. To investigate the functional effects of BepA1 activity in host cells, HeLa cells were transfected with BepA1; cell migration and cytokine secretion were assessed, revealing a decrease in pro-inflammatory cytokines in BepA1-transfected cells in response to TNF-a stimulation. These data suggest BepA1 may be deployed by B. quintana during infection to suppress the host immune response and avoid clearance from the site of infection. This research addressed a major gap in our understanding of B. quintana infections. Improving our understanding of the interactions between Bartonella and the host immune system is an essential first step in the development of improved diagnostic techniques and treatments. </p>

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QTL mapping of intestinal neutrophil variation and inflammation between threespine stickleback populations reveals links to neurodegenerative disease

10.1101/757351 ◽

2019 ◽

Author(s):

Emily A. Beck ◽

Mark C. Currey ◽

Clayton M. Small ◽

William A. Cresko

Keyword(s):

Immune System ◽

Inflammatory Response ◽

Intestinal Inflammation ◽

Threespine Stickleback ◽

Microbial Interactions ◽

Host Cells ◽

Host Immune System ◽

Complex Genetics ◽

Disease States ◽

Host Genetic

AbstractHost selection is often required to foster beneficial microbial symbionts and suppress deleterious pathogens. In animals, the host immune system is at the center of this relationship. Failed host immune system-microbial interactions can result in a persistent inflammatory response in which the immune system indiscriminately attacks resident microbes, and at times the host cells themselves, leading to diseases such as Ulcerative Colitis, Crohn’s Disease, and Psoriasis. Host genetic variation has been linked to both microbiome diversity and to severity of such inflammatory disease states in humans. However, the microbiome and inflammatory states manifest as quantitative traits, which encompass many genes interacting with one another and the environment. The mechanistic relationships among all of these interacting components are still not clear. Developing natural genetic models of host-microbe interactions is therefore fundamental to understanding the complex genetics of these and other diseases. Threespine stickleback (Gasterosteus aculeatus) fish are a tractable model for attacking this problem because of abundant population-level genetic and phenotypic variation in the gut inflammatory response. Previous work in our laboratory identified genetically divergent stickleback populations exhibiting differences in intestinal neutrophil activity. We took advantage of this diversity to genetically map variation in an emblematic element of gut inflammation – intestinal neutrophil recruitment – using an F2-intercross mapping framework. We identified three regions of the genome associated with increased intestinal inflammation containing several promising candidate genes. Within these regions we found candidates in the Coagulation/Complement System, NFkB and MAPK pathways along with several genes associated with neurodegenerative diseases commonly accompanying intestinal inflammation as a secondary symptom. These findings highlight the utility of using naturally genetically diverse ‘evolutionary mutant models’ such as threespine stickleback to better understand interactions among host genetic diversity and microbiome variation in health and disease states.

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