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1.
JACC Basic Transl Sci ; 2022 Oct 19.
Article in English | MEDLINE | ID: covidwho-2076294

ABSTRACT

SARS CoV-2 enters host cells via its Spike protein moiety binding to the essential cardiac enzyme angiotensin-converting enzyme (ACE) 2, followed by internalization. COVID-19 mRNA vaccines are RNA sequences that are translated into Spike protein, which follows the same ACE2-binding route as the intact virion. In model systems, isolated Spike protein can produce cell damage and altered gene expression, and myocardial injury or myocarditis can occur during COVID-19 or after mRNA vaccination. We investigated 7 COVID-19 and 6 post-mRNA vaccination patients with myocardial injury and found nearly identical alterations in gene expression that would predispose to inflammation, coagulopathy, and myocardial dysfunction.

2.
Microbiol Spectr ; 10(4): e0109722, 2022 08 31.
Article in English | MEDLINE | ID: covidwho-2029474

ABSTRACT

Human adenovirus type 26 (HAdV26) has been recognized as a promising platform for vaccine vector development, and very recently vaccine against COVID-19 based on HAdV26 was authorized for emergency use. Nevertheless, basic biology of this virus, namely, pathway which HAdV26 uses to enter the cell, is still insufficiently known. We have shown here that HAdV26 infection of human epithelial cells expressing low amount of αvß3 integrin involves clathrin and is caveolin-1-independent, while HAdV26 infection of cells with high amount of αvß3 integrin does not involve clathrin but is caveolin-1-dependent. Thus, this study demonstrates that caveolin-1 is limiting factor in αvß3 integrin-mediated HAdV26 infection. Regardless of αvß3 integrin expression, HAdV26 infection involves dynamin-2. Our data provide for the first-time description of HAdV26 cell entry pathway, hence increase our knowledge of HAdV26 infection. Knowing that functionality of adenovirus vector is influenced by its cell entry pathway and intracellular trafficking, our results will contribute to better understanding of HAdV26 immunogenicity and antigen presentation when used as vaccine vector. IMPORTANCE In order to fulfill its role as a vector, adenovirus needs to successfully deliver its DNA genome to the host nucleus, a process highly influenced by adenovirus intracellular translocation. Thus, cell entry pathway and intracellular trafficking determine functionality of human adenovirus-based vectors. Endocytosis of HAdV26, currently extensively studied as a vaccine vector, has not been described so far. We present here that HAdV26 infection of human epithelial cells with high expression of αvß3 integrin, one of the putative HAdV26 receptors, is caveolin-1- and partially dynamin-2-dependent. Since caveolin containing domains provide a unique environment for specific signaling events and participate in inflammatory signaling one can imagine that directing HAdV26 cell entry toward caveolin-1-mediate pathway might play role in immunogenicity of this virus. Therefore, our results contribute to better understanding of HAdV26 infection pathway, hence, can be helpful in explaining induction of immune response and antigen presentation by HAdV26-based vaccine vector.


Subject(s)
Adenoviruses, Human , COVID-19 , Adenoviruses, Human/genetics , Adenoviruses, Human/metabolism , COVID-19 Vaccines , Caveolin 1/genetics , Caveolin 1/metabolism , Clathrin/metabolism , Dynamin II/metabolism , Humans , Integrins/metabolism , Virus Internalization
3.
Advanced Therapeutics ; 5(8), 2022.
Article in English | EMBASE | ID: covidwho-2007088

ABSTRACT

Cancer gene therapy based on various gene delivery vectors has some potential but also has obvious disadvantages. In this study, a new M13 phage-based oncolytic virus is constructed that carried the RGD peptides to target tumor cells and the 3C gene of Seneca Valley virus (SVV) preceded by a eukaryotic initial transcriptional region (ITR) to transcribe an oncolytic protein to kill tumor cells. Recombinant virus particles of 1200 nm in length are obtained in large quantities by transfecting the recombinant M13 phage plasmid into the host BL2738 and are investigated in vitro in tumor cells and in vivo in tumor-bearing mice to evaluate their antitumor effect. The experiments using Hela cells confirm that the engineered M13 phage can target and enter Hela cells, and express the SVV 3C protein, resulting in apoptosis of target cells by upregulating the expression of caspase 3. Furthermore, the results of experiments in vivo also show that the recombinant phage significantly inhibits the enhanced tumor volume in nude mice compared to the control groups. The M13 phage may be engineered to fuse with a variety of oncolytic proteins to inhibit the growth of tumor cells in the future, providing a promising phage-based targeted oncolytic reagent.

4.
Journal of Hepatology ; 77:S308, 2022.
Article in English | EMBASE | ID: covidwho-1996632

ABSTRACT

Background and aims: Transforming growth factor beta (TGF-beta) signalling is a key driver of liver fibrosis. In primary sclerosing cholangitis (PSC), integrins over-expressed on injured cholangiocytes (alpha-v/beta-6) and myofibroblasts (alpha-v/beta-1) regulate TGFbeta activity. PLN-74809 is an oral, once-daily, dual-selective inhibitor of integrins alpha-v/beta-6 and alpha-v/beta-1 in development for the treatment of PSC and idiopathic pulmonary fibrosis. It has shown favourable tolerability in over 280 healthy participants, reduced TGF-beta signalling and achieved high target engagement in human lungs. Pre-clinical evaluation of antifibrotic activity resulting from dual integrin inhibition was performed to support clinical evaluation. Method: PLN-74809 was administered orally for 6 weeks in BALBc. Mdr2-/- mice with established fibrosis. A tool alpha-v/beta-6 and alpha-v/beta-1 inhibitor compound, PLN-75068, was tested therapeutically in a diet-induced mouse model of biliary fibrosis using 3, 5-diethoxycarbonyl-1, 4-dihydrocollidine (DDC). Hepatic collagen was quantified by hydroxyproline (OHP) and collagen proportionate area (CPA) and TGF-beta signalling by phosphorylated SMAD3 (pSMAD3) levels. An ex vivo study evaluated the effects of 2-day treatment with PLN-74809 on the expression of profibrotic genes, COL1A1 and COL1A2, in precision-cut liver slices (PCLivS) from tissue explants of participants with biliary fibrosis (n = 2 PSC;n = 2 primary biliary cholangitis [PBC]). A review of available blinded safety data from the enrolling Phase 2a study in participants with PSC was performed (NCT04480840). Results: PLN-74809 dose-dependently reduced OHP (up to ∼30%, p < 0.05), CPA (up to ∼50%, p < 0.05) and pSMAD3 (up to ∼40%, p < 0.001) in the BALBc.Mdr2-/- mouse model, as well as COL1A1 and COL1A2 gene expression (up to ∼30%, p = 0.0789) in PCLivS from tissue explants of participants with PSC and PBC. PLN-75068 reduced OHP (up to ∼20%, p < 0.05) in DDC-injured mice in a dose-dependent manner. PLN-74809waswell tolerated in participants with PSC. Most adverse events (AEs)were mild;nonewere severe. The most common AE was mild headache. One participant experienced serious AEs at least 20 days after the last dose of study drug, deemed not related by the investigator. One participant prematurely discontinued due to COVID-19. PLN-74809 pharmacokinetics in participants with PSC were consistent with those of healthy participants. Conclusion: Pharmacological inhibition of integrins alpha-v/beta-6 and alpha-v/beta-1 demonstrated antifibrotic activity in two models of biliary fibrosis and in PCLivS from participants with PSC or PBC. Available safety findings from participants with PSC enrolled in the ongoing Phase 2a INTEGRIS-PSC study, continue to support the favourable tolerability profile of PLN-74809.

5.
Gazzetta Medica Italiana Archivio per le Scienze Mediche ; 181(3):177-182, 2022.
Article in Italian | EMBASE | ID: covidwho-1988845

ABSTRACT

A COVID-19 patient at the limit of hospitalization (SpO2 at 93%), treated at home, found benefit in the use of antiviral medicinal mushrooms. The main agent would be Cordyceps sinensis, used in traditional Chinese medicine from 620 BC. This fungus has been studied by numerous scientists who have demonstrated its antiviral action against HIV-1, the syncytial respiratory virus, the coxsackie B3 virus, the A and “H1N1” influenza viruses, the Epstein Barr Virus. This patient treated at a time when treatments with antiretrovirals, enoxaparin or hydroxychloroquine were not yet permitted at home showed an immediate reversal of symptoms after taking Cordyceps sinensis and beta-glucans extracted from other mushrooms. The antiviral properties of the components of the drug used in this clinical case are described through the literature (mini review). The strong point, which would explain the rapid action (if it is not placebo), is the known affinity of the beta-glucans of the medicinal mushroom wall, towards the integrin-based receptors, usually present on neutrophil leukocytes, but also on the “thorns” of the CoV-2. This strong peculiarity that CoV-2 has become a weak point, if we get to inhibit it before it attacks the cells of the respiratory system.

6.
Gastroenterology ; 162(7):S-592, 2022.
Article in English | EMBASE | ID: covidwho-1967333

ABSTRACT

Background: Waning levels of anti-SARS-CoV-2 Spike (S) antibodies, particularly neutralizing, are associated with the risk of breakthrough infections. The impact of immunosuppression on antibody decay kinetics is unclear. We have previously reported a strong correlation between total anti-S antibodies and neutralization titers. Here, we report the decay kinetics in anti-S IgG antibodies across various immunosuppressive medications used in patients with CID. Methods: We recruited a volunteer sample of adults with confirmed CID eligible for SARS-CoV-2 vaccination in a prospective observational cohort study at two United States CID referral centers. All study participants received two doses of mRNA vaccine to SARSCoV- 2. To assess the durability of immunogenicity, anti-S IgG were measured at 7 (visit 3), 90 (visit 5), and 120 (visit 6) days after the 2nd dose of mRNA vaccine. The impact of various medications was assessed in repeated measures mixed model with the patient as a random effect, adjusting for gender and age, and using the group of patients on sulfasalazine, NSAIDs, or on no medications as a reference, using STATA. The half-life of anti-S IgG for a 50 percent reduction in titers at visit 3 was calculated for each medication class. Results: A total of 316 CID patients were recruited of which 148 (46.8%) had inflammatory bowel disease (IBD). Durability was assessed in 495 samples obtained in 293 patients. The arithmetic mean of anti-S IgG antibodies for each medication class at visits 3, 5, and 6 is shown in Figure 1. Overall, a 2-fold reduction in titers was observed from 7 to 90 days and 90 to 120 days (Table 1). The strongest decline was observed among patients on B cell depleting/ modulating therapies followed by those on combinations of biologics and/or small molecules and antimetabolites (methotrexate, leflunomide, thiopurines, mycophenolate mofetil, and teriflunomide). There was modest decline seen with TNFi (half-life 430.5 days, -2.15, 95% CI - 4.31 to - 1.07, p = 0.03). There was also a modest, but not significant, decline seen with Janus Kinase inhibitor (JAKi). No decline was seen with anti-IL-23 or anti-integrin medication classes. Conclusions: Antibody decay in patients with CID is not observed in patients on anti-integrins or anti-IL-23 while it is seen among patients on TNFi, JAKi, antimetabolites, and combinations of biologics and/or small molecules. Our data and those from other cohorts may be used to prioritize medication classes for boosting immunogenicity with additional doses of vaccination against SARS-CoV-2. Collection of antibody titers after booster doses is currently ongoing.(Table Presented) (Figure Presented) Figure 1: Durability of anti-spike IgG antibodies after vaccination against SARS-CoV-2 in patients with Chronic Inflammatory Disease

7.
Cancers (Basel) ; 13(23)2021 Nov 26.
Article in English | MEDLINE | ID: covidwho-1938700

ABSTRACT

For almost the entire period of the last two decades, translational research in the area of integrin-targeting radiopharmaceuticals was strongly focused on the subtype αvß3, owing to its expression on endothelial cells and its well-established role as a biomarker for, and promoter of, angiogenesis. Despite a large number of translated tracers and clinical studies, a clinical value of αvß3-integrin imaging could not be defined yet. The focus of research has, thus, been moving slowly but steadily towards other integrin subtypes which are involved in a large variety of tumorigenic pathways. Peptidic and non-peptidic radioligands for the integrins α5ß1, αvß6, αvß8, α6ß1, α6ß4, α3ß1, α4ß1, and αMß2 were first synthesized and characterized preclinically. Some of these compounds, targeting the subtypes αvß6, αvß8, and α6ß1/ß4, were subsequently translated into humans during the last few years. αvß6-Integrin has arguably attracted most attention because it is expressed by some of the cancers with the worst prognosis (above all, pancreatic ductal adenocarcinoma), which substantiates a clinical need for the respective theranostic agents. The receptor furthermore represents a biomarker for malignancy and invasiveness of carcinomas, as well as for fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF), and probably even for Sars-CoV-2 (COVID-19) related syndromes. Accordingly, the largest number of recent first-in-human applications has been reported for radiolabeled compounds targeting αvß6-integrin. The results indicate a substantial clinical value, which might lead to a paradigm change and trigger the replacement of αvß3 by αvß6 as the most popular integrin in theranostics.

8.
Kidney Dis (Basel) ; 8(4): 265-274, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1896094

ABSTRACT

Background: Inflammation is a common feature of many kidney diseases. The implicated inflammatory mediators and their underlying molecular mechanisms however are often not clear. Summary: suPAR is the soluble form of urokinase-type plasminogen activator receptor (uPAR), associated with inflammation and immune activation. It has evolved into a unique circulating kidney disease factor over the last 10 years. In particular, suPAR has multiple looks due to enzymatic cleavage and alternative transcriptional splicing of the uPAR gene. Most recently, suPAR has emerged as a systemic mediator for COVID-19 infection, associated with lung as well as kidney dysfunction. Like membrane-bound uPAR, suPAR could interact with integrins (e.g., αvß3 integrin) on podocytes, providing the molecular basis for some glomerular kidney diseases. In addition, there have been numerous studies suggesting that suPAR connects acute kidney injury to chronic kidney disease as a special kidney risk factor. Moreover, the implication of circulating suPAR levels in kidney transplantation and plasmapheresis not only indicates its relevance in monitoring for recurrence but also implies suPAR as a possible therapeutic target. In fact, the therapeutic concept of manipulating suPAR function has been evidenced in several kidney disease experimental models. Key Messages: The last 10 years of research has established suPAR as a unique inflammatory mediator for kidneys. While open questions remain and deserve additional studies, modulating suPAR function may represent a promising novel therapeutic strategy for kidney disease.

9.
Jiangsu Journal of Agricultural Sciences ; 38(2):422-428, 2022.
Article in Chinese | CAB Abstracts | ID: covidwho-1893038

ABSTRACT

In this study, we detected the viral load and protein expression of porcine epidemic diarrhea virus (PEDV) after overexpression and inhibition of integrin avbeta1 on the surface of Vero cells, and then cleared the role of integrin avbeta1 in the PEDV infection process. The results showed that the viral load and protein expression were significantly increased in the Vero cells which overexpressed integrin avbeta1, and the viral load and protein expression were significantly reduced in the Vero cells with silent integrin avbeta1 gene. Integrin avbeta1 promotes PEDV to infect Vero cells.

10.
Topics in Antiviral Medicine ; 30(1 SUPPL):266, 2022.
Article in English | EMBASE | ID: covidwho-1879920

ABSTRACT

Background: Knowledge about SARS-CoV2 infection in pregnancy and exposed newborns is deficient. We performed a longitudinal analysis of innate immune system status and determined soluble cytokines of women infected with SARS-CoV2 during pregnancy and their newborns Methods: Women with confirmed SARS-CoV2 infection (RT-PCR+ or SARS-CoV2 anti-IgM/IgG+) (COVID MOTHER group, CM n=29, median age of 31 years) and their SARS-CoV2 exposed uninfected newborns were recruited from Hospital Gregorio Marañón, Spain. Peripheral blood mononuclear cells (PBMCs), cord cells and plasma were collected at birth and 6 months later (n=15). The immunophenotyping of innate components (natural killer cells [NK] and monocytes) was studied on cryopreserved PBMCs and cord cells by multiparametric flow cytometry. Up to 4 soluble pro/anti-inflammatory cytokines were assessed in plasma and cord plasma by ELISA assay. CM was compared to a healthy non-SARS-CoV2 infected mothers' group matched by age (SARS-CoV2 PCR-and SARS-CoV2 anti-IgM/IgG-)(Uninfected Mothers, UM n=16) and their newborns (n=16) Results: On NK cell assays, CM show at baseline lower percentage of CD16++ subset, higher NKG2D and lower NKG2A expression on CD16++ and CD56++ subsets and reduced CD57 expression compared to UM;proportion of CD16++ subset and percentage of NKG2D reverted after 6 months(A). Regarding monocytes, CM show increased levels of CD62L and decreased CD49d expression on classical subset, elevated intermediate monocytes proportion and decreased CD40 expression on patrolling subset(B). No differences were found 6 months later. No newborn was infected by SARS-CoV2 and the phenotype analyzed on cord cells shows lower frequency of NK subsets compared with unexposed children and increased CD16++ subset after 6 months(C). In monocytes distribution, exposed children present lower frequency of total monocytes and its subsets than unexposed. Classical monocytes show significant changes at follow-up time-point(D). Increased TNFα and IL10 levels were found on CM compared to UM. Strong and direct correlations were observed between the age and IL6(E). No differences were observed in soluble cytokine levels comparing both groups of newborns Conclusion: SARS-CoV2 infection during pregnancy shows differences in activation, maturation and endothelial markers on innate immune system that could lead newborns clinical implications at birth. However, altered cell proportions and phenotypes found at SARS-CoV2 at birth time and on their exposed newborns is later reverted.

11.
Pharmaceuticals (Basel) ; 15(5)2022 May 17.
Article in English | MEDLINE | ID: covidwho-1875730

ABSTRACT

As COVID-19 continues to pose major risk for vulnerable populations, including the elderly, immunocompromised, patients with cancer, and those with contraindications to vaccination, novel treatment strategies are urgently needed. SARS-CoV-2 infects target cells via RGD-binding integrins, either independently or as a co-receptor with surface receptor angiotensin-converting enzyme 2 (ACE2). We used pan-integrin inhibitor GLPG-0187 to demonstrate the blockade of SARS-CoV-2 pseudovirus infection of target cells. Omicron pseudovirus infected normal human small airway epithelial (HSAE) cells significantly less than D614G or Delta variant pseudovirus, and GLPG-0187 effectively blocked SARS-CoV-2 pseudovirus infection in a dose-dependent manner across multiple viral variants. GLPG-0187 inhibited Omicron and Delta pseudovirus infection of HSAE cells more significantly than other variants. Pre-treatment of HSAE cells with MEK inhibitor (MEKi) VS-6766 enhanced the inhibition of pseudovirus infection by GLPG-0187. Because integrins activate transforming growth factor beta (TGF-ß) signaling, we compared the plasma levels of active and total TGF-ß in COVID-19+ patients. The plasma TGF-ß1 levels correlated with age, race, and number of medications upon presentation with COVID-19, but not with sex. Total plasma TGF-ß1 levels correlated with activated TGF-ß1 levels. Moreover, the inhibition of integrin signaling prevents SARS-CoV-2 Delta and Omicron pseudovirus infectivity, and it may mitigate COVID-19 severity through decreased TGF-ß1 activation. This therapeutic strategy may be further explored through clinical testing in vulnerable and unvaccinated populations.

12.
Cells ; 11(10)2022 05 19.
Article in English | MEDLINE | ID: covidwho-1862726

ABSTRACT

Most cells express several integrins. The integrins are able to respond to various cellular functions and needs by modifying their own activation state, but in addition by their ability to regulate each other by activation or inhibition. This crosstalk or transdominant regulation is strictly controlled. The mechanisms resulting in integrin crosstalk are incompletely understood, but they often involve intracellular signalling routes also used by other cell surface receptors. Several studies show that the integrin cytoplasmic tails bind to a number of cytoskeletal and adaptor molecules in a regulated manner. Recent work has shown that phosphorylations of integrins and key intracellular molecules are of pivotal importance in integrin-cytoplasmic interactions, and these in turn affect integrin activity and crosstalk. The integrin ß-chains play a central role in regulating crosstalk. In addition to Integrin-integrin crosstalk, crosstalk may also occur between integrins and related receptors, including other adhesion receptors, growth factor and SARS-CoV-2 receptors.


Subject(s)
COVID-19 , Integrins , Cell Adhesion , Cytoplasm/metabolism , Humans , Integrins/metabolism , SARS-CoV-2
13.
Modern Pathology ; 35(SUPPL 2):16, 2022.
Article in English | EMBASE | ID: covidwho-1857688

ABSTRACT

Background: More than 20% of COVID-19 patients have gastrointestinal (GI) symptoms, among which diarrhea is the most commonly seen symptom. Studies have suggested that patients with severe disease are more likely to have abdominal manifestations. Recent studies have also implicated that coagulopathy and thromboembolic as the major pathophysiological event leading to higher mortality. Besides thrombus in larger vessels, microthrombi appears to occur systemically and plays an important role in multiple organ dysfunction. However, fewer studies have focused on microthrombosis in the GI system. Design: 13 bronchial SARS-CoV-2 PCR proven autopsy cases were included in the study. Small intestinal specimens were obtained, and processed to routine hematoxylin and eosin (H&E) and CD61 immunohistochemistry (IHC). Related clinical and laboratory data were collected from patient chats. H&E and IHC slides were reviewed by two GI pathologists to evaluate histopathology and microthrombi. The degree of microthrombosis was graded as no microthrombi, focal (1- 2 per 10x), scattered (3-5 per 10x), and diffuse (≥6 per 10x). Results: Out of 13 patients (11 males, 1 female, age range 22-89 years old), 6 had diarrhea as the initial GI symptom, while others (7 patients) did not report any GI manifestations. Sections from the small intestine showed no acute inflammation in all cases. CD61 positive microthrombi was seen in all small intestine specimens, mainly located in the microvasculature of mucosa, and occasionally submucosal tissue. Patients who had diarrhea, 4/6 (66.7%) showed diffuse (greater than 6 per 10x field) microthrombi in the small intestine. In contrast, patients without GI symptoms, only 2/7 (28.5%) had diffuse microthrombi. Data from lab tests showed the D-dimer appeared to be higher in patients with diarrhea (median, 4067, range from 867 to 10000 ng/ml) compared to patients without diarrhea (median, 2820, range from 298 to 10000 ng/ml). There was no significant difference between median levels of C-reactive protein, prothrombin time (PT) and partial thromboplastin time (aPTT) between patients with or without diarrhea. Conclusions: Our study highlights that microthrombi frequently occurs in the GI system as reported in other organs. COVID-19 patients with initial GI manifestations, may develop severe microthrombosis and progress to sever disease.

14.
Modern Pathology ; 35(SUPPL 2):969-970, 2022.
Article in English | EMBASE | ID: covidwho-1857373

ABSTRACT

Background: Since the first case of COVID19 infection in 2019, this RNA virus has led an unprecedented pandemic that infected more than 232 million people. Although the disease is studied extensively, much remains poorly understood. Here, we performed the first correlation study on the peripheral blood morphology and immunophenotype of the white blood cells (WBCs) from COVID19 patients. Design: A total of 52 samples from COVID19 patients and 15 blood samples as control group were analyzed. COVID19 patients were divided into two groups based on clinical severity, severe (respiratory failure) or non-severe (hospitalized but stable). The controls were the patients with negative COVID19 results by PCR and antibody tests. The WBC morphology was examined either by blood smear review or via CellaVision DM analyzer captured images. Navios flow cytometer and Beckman Kaluza C software were used for immunophenotype analysis. Two-tailed T-test was performed on the COVID19 groups and the control group Results: Almost all COVID19 patients showed marked neutrophilia and lymphopenia on the CBC tests. Morphologically, the neutrophils showed irregularities like hypogranulation, toxic granules and pseudo Pelger-Huet anomaly (Fig 1A). In severe COIVD19 group, there was an increase in neutrophils with immatures phenotypes, showing CD33 positivity while CD10, CD13 and CD16 negative (Fig 1B). Conversely, the CD10(+) mature neutrophils aberrantly expressed CD56 (Fig 1B). The percentage of CD56(+) neutrophils was significantly higher in both COVID19 groups, suggesting a stronger cellular adhesion and interaction. The monocytes from the COVID19 patients had increased cytoplasm with cytoplasmic protrusion and vacuolization (Fig 2A). Phenotypically they were positive for CD13, CD33, CD38 and HLA-DR. The lymphocytes were also atypical, including increased cytoplasm with large granules and vacuoles. Phenotypically, they are activated, expressing CD38, HLA-DR, and mainly α/β subtype. Giant platelets with cytoplasmic vacuoles and projections were easily seen. Platelet aggregations were observed (Fig 2B). These platelets were CD45(-) and expressed CD61 at lower-than-normal intensity, while expressing increased CD42b intensity when compared to the control group on a log scale. Conclusions: Despite being a small study, we were able to correlate the morphologic and phenotypic alterations of the WBCs in COVID19 patients. As such, this helped to explain some of the clinical hematologic manifestation of the disease. (Figure Presented).

15.
J Biol Chem ; 298(3): 101695, 2022 03.
Article in English | MEDLINE | ID: covidwho-1851422

ABSTRACT

Vascular endothelial cells (ECs) form a critical interface between blood and tissues that maintains whole-body homeostasis. In COVID-19, disruption of the EC barrier results in edema, vascular inflammation, and coagulation, hallmarks of this severe disease. However, the mechanisms by which ECs are dysregulated in COVID-19 are unclear. Here, we show that the spike protein of SARS-CoV-2 alone activates the EC inflammatory phenotype in a manner dependent on integrin ⍺5ß1 signaling. Incubation of human umbilical vein ECs with whole spike protein, its receptor-binding domain, or the integrin-binding tripeptide RGD induced the nuclear translocation of NF-κB and subsequent expression of leukocyte adhesion molecules (VCAM1 and ICAM1), coagulation factors (TF and FVIII), proinflammatory cytokines (TNFα, IL-1ß, and IL-6), and ACE2, as well as the adhesion of peripheral blood leukocytes and hyperpermeability of the EC monolayer. In addition, inhibitors of integrin ⍺5ß1 activation prevented these effects. Furthermore, these vascular effects occur in vivo, as revealed by the intravenous administration of spike, which increased expression of ICAM1, VCAM1, CD45, TNFα, IL-1ß, and IL-6 in the lung, liver, kidney, and eye, and the intravitreal injection of spike, which disrupted the barrier function of retinal capillaries. We suggest that the spike protein, through its RGD motif in the receptor-binding domain, binds to integrin ⍺5ß1 in ECs to activate the NF-κB target gene expression programs responsible for vascular leakage and leukocyte adhesion. These findings uncover a new direct action of SARS-CoV-2 on EC dysfunction and introduce integrin ⍺5ß1 as a promising target for treating vascular inflammation in COVID-19.


Subject(s)
COVID-19 , Inflammation , Integrin alpha5beta1 , NF-kappa B , Spike Glycoprotein, Coronavirus , Tumor Necrosis Factor-alpha , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , Human Umbilical Vein Endothelial Cells , Humans , Inflammation/metabolism , Inflammation/pathology , Inflammation/virology , Integrin alpha5beta1/metabolism , Interleukin-6/metabolism , NF-kappa B/metabolism , Oligopeptides , SARS-CoV-2 , Signal Transduction , Spike Glycoprotein, Coronavirus/metabolism , Tumor Necrosis Factor-alpha/metabolism
16.
American Family Physician ; 105(4):406-411, 2022.
Article in English | EMBASE | ID: covidwho-1848264

ABSTRACT

Ulcerative colitis is a relapsing and remitting inflammatory bowel disease of the large intestine. Risk factors include recent Salmonella or Campylobacter infection and a family history of ulcerative colitis. Diagnosis is suspected based on symptoms of urgency, tenesmus, and hematochezia and is confirmed with endoscopic findings of continuous inflammation from the rectum to more proximal colon, depending on the extent of disease. Fecal calprotectin may be used to assess disease activity and relapse. Medications available to treat the inflammation include 5-aminosalicylic acid, corticosteroids, tumor necrosis factor-alpha antibodies, anti-integrin antibodies, anti-interleukin-12 and -23 antibodies, and Janus kinase inhibitors. Choice of medication and method of delivery depend on the location and severity of mucosal inflammation. Other treatments such as fecal microbiota transplantation are considered experimental, and complementary therapies such as probiotics and curcumin have mixed data. Surgical treatment may be needed for fulminant or refractory disease. Increased risk of colorectal cancer and use of immunosuppressive therapies affect the preventive care needs for these patients.

17.
Front Cardiovasc Med ; 8: 779073, 2021.
Article in English | MEDLINE | ID: covidwho-1809356

ABSTRACT

Background: The fatal consequences of an infection with severe acute respiratory syndrome coronavirus 2 are not only caused by severe pneumonia, but also by thrombosis. Platelets are important regulators of thrombosis, but their involvement in the pathogenesis of COVID-19 is largely unknown. The aim of this study was to determine their functional and biochemical profile in patients with COVID-19 in dependence of mortality within 5-days after hospitalization. Methods: The COVID-19-related platelet phenotype was examined by analyzing their basal activation state via integrin αIIbß3 activation using flow cytometry and the proteome by unbiased two-dimensional differential in-gel fluorescence electrophoresis. In total we monitored 98 surviving and 12 non-surviving COVID-19 patients over 5 days of hospital stay and compared them to healthy controls (n = 12). Results: Over the observation period the level of basal αIIbß3 activation on platelets from non-surviving COVID-19 patients decreased compared to survivors. In line with this finding, proteomic analysis revealed a decrease in the total amount of integrin αIIb (ITGA2B), a subunit of αIIbß3, in COVID-19 patients compared to healthy controls; the decline was even more pronounced for the non-survivors. Consumption of the fibrin-stabilizing factor coagulation factor XIIIA (F13A1) was higher in platelets from COVID-19 patients and tended to be higher in non-survivors; plasma concentrations of the latter also differed significantly. Depending on COVID-19 disease status and mortality, increased amounts of annexin A5 (ANXA5), eukaryotic initiation factor 4A-I (EIF4A1), and transaldolase (TALDO1) were found in the platelet proteome and also correlated with the nasopharyngeal viral load. Dysregulation of these proteins may play a role for virus replication. ANXA5 has also been identified as an autoantigen of the antiphospholipid syndrome, which is common in COVID-19 patients. Finally, the levels of two different protein disulfide isomerases, P4HB and PDIA6, which support thrombosis, were increased in the platelets of COVID-19 patients. Conclusion: Platelets from COVID-19 patients showed significant changes in the activation phenotype, in the processing of the final coagulation factor F13A1 and the phospholipid-binding protein ANXA5 compared to healthy subjects. Additionally, these results demonstrate specific alterations in platelets during COVID-19, which are significantly linked to fatal outcome.

18.
Viruses ; 14(5)2022 04 25.
Article in English | MEDLINE | ID: covidwho-1810326

ABSTRACT

The vascular barrier is heavily injured following SARS-CoV-2 infection and contributes enormously to life-threatening complications in COVID-19. This endothelial dysfunction is associated with the phlogistic phenomenon of cytokine storms, thrombotic complications, abnormal coagulation, hypoxemia, and multiple organ failure. The mechanisms surrounding COVID-19 associated endotheliitis have been widely attributed to ACE2-mediated pathways. However, integrins are emerging as possible receptor candidates for SARS-CoV-2, and their complex intracellular signaling events are essential for maintaining endothelial homeostasis. Here, we showed that the spike protein of SARS-CoV-2 depends on its RGD motif to drive barrier dysregulation by hijacking integrin αVß3, expressed on human endothelial cells. This triggers the redistribution and internalization of major junction protein VE-Cadherin which leads to the barrier disruption phenotype. Both extracellular and intracellular inhibitors of integrin αVß3 prevented these effects, similarly to the RGD-cyclic peptide compound Cilengitide, which suggests that the spike protein-through its RGD motif-binds to αVß3 and elicits vascular leakage events. These findings support integrins as an additional receptor for SARS-CoV-2, particularly as integrin engagement can elucidate many of the adverse endothelial dysfunction events that stem from COVID-19.


Subject(s)
COVID-19 , Spike Glycoprotein, Coronavirus , Cadherins , Endothelial Cells/metabolism , Humans , Integrin alphaVbeta3 , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism
19.
Viruses ; 14(4)2022 03 29.
Article in English | MEDLINE | ID: covidwho-1798881

ABSTRACT

Integrins represent a gateway of entry for many viruses and the Arg-Gly-Asp (RGD) motif is the smallest sequence necessary for proteins to bind integrins. All Severe Acute Respiratory Syndrome Virus type 2 (SARS-CoV-2) lineages own an RGD motif (aa 403-405) in their receptor binding domain (RBD). We recently showed that SARS-CoV-2 gains access into primary human lung microvascular endothelial cells (HL-mECs) lacking Angiotensin-converting enzyme 2 (ACE2) expression through this conserved RGD motif. Following its entry, SARS-CoV-2 remodels cell phenotype and promotes angiogenesis in the absence of productive viral replication. Here, we highlight the αvß3 integrin as the main molecule responsible for SARS-CoV-2 infection of HL-mECs via a clathrin-dependent endocytosis. Indeed, pretreatment of virus with αvß3 integrin or pretreatment of cells with a monoclonal antibody against αvß3 integrin was found to inhibit SARS-CoV-2 entry into HL-mECs. Surprisingly, the anti-Spike antibodies evoked by vaccination were neither able to impair Spike/integrin interaction nor to prevent SARS-CoV-2 entry into HL-mECs. Our data highlight the RGD motif in the Spike protein as a functional constraint aimed to maintain the interaction of the viral envelope with integrins. At the same time, our evidences call for the need of intervention strategies aimed to neutralize the SARS-CoV-2 integrin-mediated infection of ACE2-negative cells in the vaccine era.


Subject(s)
COVID-19 , Vaccines , Angiotensin-Converting Enzyme 2 , Antibodies, Neutralizing , COVID-19/prevention & control , Endocytosis , Endothelial Cells/metabolism , Humans , Integrin alphaV/metabolism , Integrin beta3/metabolism , Oligopeptides , Protein Binding , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics
20.
Stroke ; 53(SUPPL 1), 2022.
Article in English | EMBASE | ID: covidwho-1724002

ABSTRACT

Patients with significant cerebrovascular comorbidities (e.g. brain ischemia, vascular dementia) are more affected and are more likely to have worsened post-acute neurologic sequelae after SARSCoV-2 infection. This may be due to viral invasion and propagation in brain endothelial cells (BECs) and disruption of the blood-brain barrier (BBB). Viral spike protein used to bind and infect host cells encodes an arginine-glycine-aspartic acid (RGD) motif that it may use to bind integrins cell receptors that play an important role in cerebrovascular integrity. Therefore, integrins may represent an acute and post-acute SARS-CoV-2 therapeutic target. However, the interplay between vascular dysregulation, integrin function, and COVID-19 is unclear. As we have previously demonstrated that activation of the integrin α5 plays a key role in BBB breakdown, stroke injury, OGD/R, SARS-CoV-2 infection, and its inhibition with the clinically validated peptide ATN-161 is therapeutic in these conditions, we hypothesize that SARS-CoV-2 alters BEC α5 integrin (and associated tight junction protein) expression as a means of infecting and altering cerebrovascular integrity, and this can be prevented by ATN-161. Methods: Mouse BECs (bEnd3) were inoculated with heat-inactivated SARS-CoV-2 (Isolate USAWA1/2020) or delta variant of SARS-CoV-2 spike protein for 24 h then later exposed to hypoxia for 6h to model the effects of in vivo pulmonary infection. Cells were pretreated with ATN-161 (1, 5, and 10μM) 1h before SARS-CoV-2 challenge and during hypoxia. α5 and claudin-5 proteins were analyzed by immunoblotting. Results: Both SARS-CoV-2 inoculations induced integrin α5 and decreased claudin-5 expression (delta > SARS-CoV-2) in a dose-dependent fashion, although higher doses of SARS-CoV-2 (2.5 and 5 μg) had no effect on these proteins. SARS-CoV-2 spike protein challenge at 0.5 μg followed by hypoxia resulted in increased α5 and decreased claudin-5 expression in either hypoxia or SARSCoV-2+hypoxia combination. ATN-161 (10μM) pretreatment inhibited SARS-CoV-2+hypoxia-induced α5 upregulation and restored claudin-5 loss. In addition to its demonstrated anti-viral effects, ATN161 may be an important therapy for SARS-CoV-2-mediated cerebrovascular injury.

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