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  1. FMRP – the protein behind immunotherapy resistance By Jim Cornall https://www.labiotech.eu/trends-news/fmrp-protein-behind-immunotherapy-resistance/ Immunotherapy is a cutting-edge approach to treating cancer by turning the patient’s own immune system against their tumor. Despite success rates, immunotherapy has time and again met with a stubborn obstacle: tumor cells often evade the “radar” of immune cells seeking to destroy them. This in turn leads to treatment resistance, which in many cases would benefit from a deeper understanding of mechanisms that can help circumvent it. A new study led by scientists at Swiss university EPFL has now uncovered a protein that plays a key role in helping tumors evade immune destruction. The protein, fragile X mental retardation protein (FMRP), regulates a network of genes and cells in the tumor microenvironment that contribute to its ability to “hide” from immune cells. Normally, FMRP is involved in regulating protein translation and the stability of mRNA in neurons. But the researchers found it is up-regulated in multiple forms of cancer. The study, published in Science, was led by researchers in the group of Douglas Hanahan at the Swiss Institute for Experimental Cancer Research (ISREC) and the Lausanne Branch of the Ludwig Institute for Cancer Research, along with colleagues from the University Hospital of Lausanne (CHUV) and other Swiss institutions. The discovery has also led to an EPFL spin-off, Opna Bio, whose staff were also involved in the research. FMRP But why FMRP? The idea came from previous studies showing that cancer cells that naturally overexpress FMRP are invasive and metastatic. Other studies show that if, in contrast, FMRP fails to be expressed in developing neurons it can lead to cognitive defects (hence the “mental retardation” part of the protein’s name). With this evidence in mind, the researchers investigated the expression of FMRP in human tumors. They then assessed its tumor-promoting functions in mouse models of cancer, and finally studied its association with prognosis for human cancer patients. The study involved several data-gathering steps. First, the scientists performed immunostaining for FMRP on tissue from human tumors. The majority of the tumors tested positive, while corresponding normal tissue did not. This showed FMRP is specifically and highly expressed in cancer cells. The team then moved onto the main part of their research, which was to determine the functional significance of FMRP in those tumors –they express the protein, but what does it do? FMRP and the immune system To explore this, the scientists developed lines of “knockout” cancer cells. Knockout cells or organisms are genetically engineered to lose – “knock out” – a specific gene in order to find clues about its function. Essentially, whatever change occurs in knockout cells compared to cells that still have the gene – called “wild-type”– can generally be traced back to the missing gene. In this case, the scientists used CRISPR-Cas9 gene-editing to knock out the gene FMR1, which produces FMRP in mouse cancer cells arising from pancreas, colon, breast, and skin melanocytes. They then compared the FMRP-knockout cancer cells to cancer cells that still had the FMR1 gene and thus expressed the FMRP protein. The researchers evaluated survival rates between mice with tumors containing FMRP-knockout cancer cells and those with FMRP-wild-type cells, first in mice whose immune systems had been compromised. The comparison revealed similar survival rates. In contrast, when they compared the knockout tumors to wild-type tumors growing in mice with properly functioning immune systems, they found that tumors without FMRP were growing more slowly, and the animals survived longer. This showed FMRP is not involved in stimulating tumor growth per se, and rather implicated the adaptive immune system (the part of the immune system that is “trained” with vaccines). This was further confirmed by the observation that wild-type tumors had very few infiltrating T lymphocytes, whereas knockout tumors were highly inflamed. Depleting T cells from the FMRP-knockout tumors caused them to start growing more rapidly and reduced the survival rates of the mice, meaning that FMRP is somehow involved in tumors evading the immune system. How tumors with FMRP defend against immune cells The team continued with molecular genetic profiling of both knockout and wild-type tumors. This revealed significant differences in gene transcription across the entire genome, suggesting that FMRP interacts with multiple genes. In addition, the tumors showed marked differences in the abundance of cancer cells, macrophages, and T cells, further implicating the role of FMRP in modulating components of the immune system. The next phase of the study looked at the production of specific factors associated with the distinctive immune responses – evasion versus attack. The tumors expressing FMRP were found to produce interleukin-33, a protein that induces the production of regulatory T cells, a specialized subpopulation of T cells that inhibit immune responses. They also produce protein S, a glycoprotein known to promote tumor growth. Finally, the tumors produce exosomes – cell organelles that triggered the production of a type of macrophage cell that normally helps with wound healing and tissue repair. All three factors are immunosuppressive and contribute to the tumor’s barrier against attacks from T lymphocytes. In contrast, the FMRP knockout tumors cells actually downregulated all three factors (interleukin-33, protein S, and exosomes) while they up-regulated a different chemokine, C-C motif chemokine ligand 7 (CCL7), which helps recruit and activate T cells. This process is further aided by inducing immunostimulatory (and not immunosuppressive) macrophages. These cells produce three other proinflammatory proteins that work with CCL7 in recruiting T cells. Predicting immunotherapy outcomes in human patients In a clinical context, the question is whether levels of FMRP can help form a prognosis for patients undergoing immunotherapy. Counterintuitively, both mRNA of the FMR1 gene and FMRP protein levels were insufficient for predicting outcomes in cohorts of cancer patients. To address this, the researchers built on the fact that, in the cell, FMRP up- and down-modulates the stability of mRNA by binding it directly. This means FMRP might change RNA levels that could be picked up in transcriptome datasets, which could be collected to define a “gene signature” to help track its functional activity. The approach worked, allowing the scientists to track a gene signature of FMRP’s cancer regulatory activity with a network of 156 genes. The FMRP cancer network activity signature proved to be prognostic for poor survival across multiple human cancers, consistent with the immunosuppressive effects of FMRP, and, in some patients, it was linked to poor responses to immunotherapy treatments. The work shows that FMRP regulates a network of genes and cells in the tumor microenvironment, all of which help tumors to evade immune destruction. Hanahan said: “Having studied the complex cellular composition of solid tumors for decades, I am personally astonished by our discovery that a co-opted neuronal regulatory protein – FMRP – can orchestrate the formation of a multi-faceted protective barrier against attack by the immune system that consequently limits the benefit of immunotherapies, thereby presenting FMRP as a new therapeutic target for cancer.”
  2. Aberrant hyperexpression of the RNA binding protein FMRP in tumors mediates immune evasion https://www.science.org/doi/10.1126/science.abl7207 Many human cancers manifest the capability to circumvent attack by the adaptive immune system. In this work, we identified a component of immune evasion that involves frequent up-regulation of fragile X mental retardation protein (FMRP) in solid tumors. FMRP represses immune attack, as revealed by cancer cells engineered to lack its expression. FMRP-deficient tumors were infiltrated by activated T cells that impaired tumor growth and enhanced survival in mice. Mechanistically, FMRP’s immunosuppression was multifactorial, involving repression of the chemoattractant C-C motif chemokine ligand 7 (CCL7) concomitant with up-regulation of three immunomodulators—interleukin-33 (IL-33), tumor-secreted protein S (PROS1), and extracellular vesicles. Gene signatures associate FMRP’s cancer network with poor prognosis and response to therapy in cancer patients. Collectively, FMRP is implicated as a regulator that orchestrates a multifaceted barrier to antitumor immune responses. INTRODUCTION Cancer biology and therapy have been transformed by knowledge about immunoregulatory mechanisms that govern adaptive immunity. Although some forms of treatment resistance are related to the intentionally transitory operations of the adaptive immune system, others reflect more subtle requirements to modulate the immune system in different contexts. In this work, we identified an immunoregulatory mechanism involving the neuronal RNA binding protein fragile X mental retardation protein (FMRP), which broadly regulates protein translation and mRNA stability and is aberrantly up-regulated in multiple forms of cancer. RATIONALE This study was motivated by reports that cancer cells naturally overexpressing FMRP, whose loss of expression in developing neurons causes cognitive defects, were invasive and metastatic. We investigated the expression of FMRP in human tumors, further assessed its tumor-promoting functions in mouse models of cancer, and evaluated its association with prognosis for human cancer patients. RESULTS When human tumor tissue microarrays were immunostained for expression of FMRP, a majority of tumors expressed FMRP, whereas cognate normal tissues did not. To investigate the functional significance of this broad up-regulation, the FMR1 gene was ablated through CRISPR-Cas9 gene editing (FMRP-KO, where KO indicates knockout) in mouse cancer cell lines that were inoculated into both immunodeficient and syngeneic immunocompetent mice to establish tumors in parallel with wild-type (WT) FMRP-expressing cell lines. Mice bearing FMRP-KO tumors had similar survival compared with isogenic WT tumors in immunodeficient hosts, indicating that FMRP was not involved in stimulating tumor growth per se. By contrast, tumor growth was impaired and survival extended in immunocompetent hosts, implicating the adaptive immune system. Indeed, FMRP-expressing WT tumors were largely devoid of T cells, whereas FMRP-KO tumors were highly inflamed. Depletion of CD8 and CD4 T cells restored tumor growth and reduced survival, implicating FMRP in immune evasion in WT tumors. WT and FMRP-KO tumors were profiled by single-cell RNA sequencing, revealing marked differences in genome-wide transcription and abundance of cancer cells, macrophages, and T cells. To elucidate the effects of this multifaceted regulatory protein, we performed several functional perturbations, revealing that: FMRP-expressing cancer cells produce the chemokine interleukin-33 (IL-33), which induces regulatory T cells, as well as tumor-secreted protein S (PROS1) ligand and exosomes that elicit tumor-promoting (M2) macrophages. Both cell types are immunosuppressive, collectively contributing to the barrier against T cell attack. By contrast, FMRP-KO cancer cells down-regulate all three factors and up-regulate C-C motif chemokine ligand 7 (CCL7), which helps recruit and activate T cells. Additionally, immunostimulatory macrophages develop in this context that express three proinflammatory chemokines—CCL5, CXCL9, and CXCL10—which cooperate with CCL7 in recruiting T cells. Finally, neither FMR1 mRNA nor FMRP protein levels were sufficient to predict outcomes in cohorts of cancer patients. Recognizing FMRP’s function as an RNA binding protein that modulates mRNA stability and hence levels in transcriptome datasets, a gene signature reflecting FMRP’s cancer regulatory activity (involving 156 genes) was developed by comparing FMRP-expressing versus FMRP-deficient cancer cells, both in culture and within tumors. Our FMRP cancer activity signature was prognostic for survival across multiple human cancers; anticorrelated with the intensity of T cell infiltration in different tumor types, consistent with FMRP’s immunosuppressive effects; and was associated with comparatively poor responses to immune checkpoint inhibitors and immune-dependent chemotherapy in selected cohorts. CONCLUSION FMRP is revealed as a regulator of a network of genes and cells in the tumor microenvironment that contribute to the capability of tumors to evade immune destruction.
  3. MedicAlert have announced a change in their membership fees. From 1st October 2022 the annual fee is £36, or £33 if you pay by direct debit. https://www.proteinsdeficiency.com/services/medic-alert.php
  4. Hereditary Thrombophilia Testing Among Hospitalized Patients: Is It Warranted? Omar K. Abughanimeh , Rosalyn I. Marar, Mohammad Tahboub, Anahat Kaur, Ayman Qasrawi, Mouhanna Abu Ghanimeh, Timothy Pluard Published: May 09, 2022 (see history) DOI: 10.7759/cureus.24855 Cite this article as: Abughanimeh O K, Marar R I, Tahboub M, et al. (May 09, 2022) Hereditary Thrombophilia Testing Among Hospitalized Patients: Is It Warranted?. Cureus 14(5): e24855. doi:10.7759/cureus.24855 Hereditary thrombophilias (HTs) are a group of inherited disorders that predispose the carrier to venous thromboembolism (VTE). It is estimated that 7% of the population has some form of HT. Although testing for HT has become routine for many hospitalized patients, knowing when to order the tests and how to interpret the results remains challenging. In the United States, there are no clear guidelines regarding testing for HT. We conducted a study to evaluate the utilization of HT testing among hospitalized patients to examine its impact on immediate management decisions and overall cost burden. In addition, we discuss the common reasons for healthcare providers to order these tests and review the data behind these reasons in the literature. Our study demonstrated that HT testing during hospitalization had a limited role in changing management and was associated with a significant cost. The decision to order HT tests should be considered following an individualized clinical risk assessment. https://www.cureus.com/articles/92682-hereditary-thrombophilia-testing-among-hospitalized-patients-is-it-warranted
  5. https://www.docwirenews.com/vte-knowledge-hub/protein-c-or-protein-s-deficiency-associates-with-paradoxically-impaired-platelet-dependent-thrombus-and-fibrin-formation-under-flow/ Res Pract Thromb Haemost. 2022 Mar 7;6(2):e12678. doi: 10.1002/rth2.12678. eCollection 2022 Feb. March 14, 2022 BACKGROUND: Low plasma levels of protein C or protein S are associated with venous thromboembolism rather than myocardial infarction. The high coagulant activity in patients with thrombophilia with a (familial) defect in protein C or S is explained by defective protein C activation, involving thrombomodulin and protein S. This causes increased plasmatic thrombin generation. OBJECTIVE: Assess the role of platelets in the thrombus- and fibrin-forming potential in patients with familial protein C or protein S deficiency under high-shear flow conditions. PATIENTS/METHODS: Whole blood from 23 patients and 15 control subjects was perfused over six glycoprotein VI-dependent microspot surfaces. By real-time multicolor microscopic imaging, kinetics of platelet thrombus and fibrin formation were characterized in 49 parameters. RESULTS AND CONCLUSION: Whole-blood flow perfusion over collagen, collagen-like peptide, and fibrin surfaces with low or high GPVI dependency indicated an unexpected impairment of platelet activation, thrombus phenotype, and fibrin formation but unchanged platelet adhesion, observed in patients with protein C deficiency and to a lesser extent protein S deficiency, when compared to controls. The defect extended from diminished phosphatidylserine exposure and thrombus contraction to delayed and suppressed fibrin formation. The mechanism was thrombomodulin independent, and may involve negative platelet priming by plasma components.
  6. Genetic Variants in the Protein S ( PROS1 ) Gene and Protein S Deficiency in a Danish Population Ole Halfdan Larsen, Alisa D Kjaergaard, Anne-Mette Hvas, Peter H Nissen TH Open 2021 Oct 28;5(4):e479-e488. doi: 10.1055/s-0041-1736636. eCollection 2021 Oct. PMID: 34729451 PMCID: PMC8553426 DOI: 10.1055/s-0041-1736636 https://pubmed.ncbi.nlm.nih.gov/34729451/ Protein S (PS) deficiency is a risk factor for venous thromboembolism (VTE) and can be caused by variants of the gene encoding PS ( PROS1 ). This study aimed to evaluate the clinical value of molecular analysis of the PROS1 gene in PS-deficient participants. We performed Sanger sequencing of the coding region of the PROS1 gene and multiplex ligation-dependent probe amplification to exclude large structural rearrangements. Free PS was measured by a particle-enhanced immunoassay, while PS activity was assessed by a clotting method. A total of 87 PS-deficient participants and family members were included. In 22 index participants, we identified 13 PROS1 coding variants. Five variants were novel. In 21 index participants, no coding sequence variants or structural rearrangements were identified. The free PS level was lower in index participants carrying a PROS1 variant compared with index participants with no variant (0.51 [0.32-0.61] vs. 0.62 [0.57-0.73] × 10 3 IU/L; p < 0.05). The p.(Thr78Met) variant was associated with only slightly decreased free PS levels (0.59 [0.53-0.66] × 10 3 IU/L) compared with the p.(Glu390Lys) variant (0.27 [0.24-0.37] × 10 3 IU/L, p < 0.01). The frequency of VTE in participants with a coding PROS1 variant was 43 and 17% in the group with normal PROS1 gene ( p = 0.05). In conclusion, we report 13 PROS1 coding variants including five novel variants. PS levels differ by PROS1 variant and the frequency of VTE was higher when a coding PROS1 variant was present. Hence, molecular analysis of the PROS1 gene may add clinical value in the diagnostic work-up of PS deficiency.
  7. The Level of vWF Antigen and Coagulation Markers in Hospitalized Patients with Covid-19 https://www.dovepress.com/the-level-of-vwf-antigen-and-coagulation-markers-in-hospitalized-patie-peer-reviewed-fulltext-article-JBM Authors Al Otair H, AlSaleh K, AlQahtany FS, Al Ayed K, Al Ammar H, Al Mefgai N, Al Zeer F Published 30 August 2021 Volume 2021:12 Pages 809—817 Department of Medicine, King Saud University Medical City, King Saud University, P.O. Box 2925(38), Riyadh, 11461, Saudi Arabia Background: The coagulopathy of COVID-19 still awaits more clarification, and one approach that has not been investigated is to compare the hemostatic changes between COVID-19 and non-COVID-19 infected patients. Objective: This study aims to study COVID-19 coagulopathy by measuring markers of endothelial injury and coagulation, including anticoagulants (TFPI, protein C, protein S, and AT) in COVID-19 patients and compare them with non-COVID-19 patients early in the course of the disease. Methodology: This is an observational, prospective cross-sectional study comparing the levels of protein C, protein S, antithrombin (AT) III, clotting factor (F) VIII, von Willebrand factor (vWF) and coagulation screening tests (PT and a PTT), fibrinogen, D-dimer in COVID-19 patients admitted during the same time with non-COVID-19 infections. The demographic and clinical data of the patients were collected from electronic medical records during admission. Blood tests were extracted within 24 hours of admission for both groups. Results: Fifty-four (66.7% males) consecutive COVID-19 patients and 24 (59% males) non-COVID-19 controls were enrolled in the study from October 2020 till December 2020. COVID-19 patients were significantly older than non-COVID-19 (57.7± 14.2 vs 50± 19.8 years, p= 0.005). Fibrinogen level was significantly higher in COVID-19 patients compared to controls (5.9± 1.48 vs 3.9± 1.57, p< 0.001). There was no statistically significant difference in the level of FVIII, protein C, S, ATIII, and D-dimer between the two groups. The level of vWF Ag was statistically higher in COVID-19 patients (276.7± 91.1 vs 184.7± 89.4, p=0.0001). There was significant thrombocytopenia and lymphopenia among COVID-19 patients. Inflammatory markers, CRP, ferritin, and LDH, were increased in COVID-19 patients compared to non-COVID-19, but the difference was not statistically significant. High fibrinogen and vWF AG levels were the two independent variables found in COVID-19 patients. Conclusion: The level of vWF Ag is increased early in the course of COVID-19 infection. This can be used as a biomarker for endothelial injury, which is peculiar to COVID-19 infection. Introduction Coronavirus disease (COVID-19) started in Wuhan, China, as multiple cases of pneumonia of unclear cause.1–3 On 11th March 2020, WHO declared COVID-19 as a pandemic after affecting more than 118,319 patients globally.4 Currently, more than 127 million cases are confirmed worldwide with 2,799,030 deaths.5 In the Kingdom of Saudi Arabia, the total number of cases has reached 388,860 with 6656 deaths, according to the last report (29th March 2021) from the Saudi Ministry of Health and the Saudi Centre of Disease Prevention and Control (CDC).6 It is well known now that severe acute respiratory syndrome corona virus2 (SARS-CoV-2) utilizes angiotensin-converting enzyme 2 (ACE2) receptor to enter human host cells.31 Specifically, SARS-CoV-2 surface spike protein binds to human ACE2 on the surface of the cell through its receptor-binding domain (RBD) which is activated by transmembrane protease serine 2 (TMPRSS2). This in turn induces virus-plasma membrane fusion and subsequent cell entry. Therefore, it plays a fundamental role in SARS-CoV-2 cellular infectivity as well as reduced viral recognition by neutralizing antibodies. Its expression by endothelial cells of the respiratory and digestive tracts explains many of the clinical presentations of COVID-19 infection.32–34 Patients with DM have an upregulation of ACE2 expression (total and glycosylated forms) on the surface of the cells secondary to the renin-angiotensin system activation.35 This contributes to the higher prevalence and worse prognosis of COVID-19 infection in patients with type 2 DM in conjunction with microvascular damage and overt inflammation mediated by high plasma levels of IL-6 and other pro-inflammatory cytokine.36 Similarly, the higher binding of COVID‐19 and ACE2 could explain the higher rate of hypertension among patients infected with covid-19 and their complicated course. ACE2 is a known modulator of the renin-angiotensin system (RAS) and responsible for many of the pathways underlying hypertension.37 Recently, many papers have reported an increased prevalence of venous and arterial thrombosis in COVID-19 patients.7–10 This is especially true in patients with non-O blood groups who have higher risk for arterial and venous thrombosis. Possibly related to alteration in hemostatic markers, vWF and FVIII, and over-inflammation.38 Similarly, postmortem studies have demonstrated the presence of widespread multiple microthrombi.11 Pulmonary embolism and deep vein thrombosis have also been reported in-69%of critically ill patients.9 During the last year, COVID-19 coagulopathy has been the subject of numerous publications, and it is now well established that the laboratory findings in COVID-19 coagulopathy are quite different from the usual findings of disseminated intravascular coagulation (DIC) seen commonly in septicemia.12,13 In hospitalized COVID-19 patients, the most observed abnormalities are elevations of plasma fibrinogen and D-dimer, along with a parallel rise in markers of inflammation (eg, CRP and cytokines), and minimum prolongation of prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT) and mild thrombocytopenia (platelet count ~100 x109/L).14,15 This does not fit in the findings noted in classical DIC.16 These unique features of COVID-19 have been researched extensively in the last few months, and no consensus on its pathophysiology has been reached. A recent article in Nature has described it rightly as the COVID-19 mystery.17,18 With this background in mind, we conducted a cross-sectional study to explore the mechanism of clot formation in COVID-19, specifically the level of clotting factor (F) VIII, von Willebrand factor (vWF), and natural anticoagulants in COVID-19 infection on admission to the hospital and compared it to the non-COVID-19 patients. We believe this approach of comparing markers of endothelial injury and coagulation between patients with COVID-19 pneumonia and bacterial pneumonia would bring out differences in the coagulopathy between these two groups of patients and thereby shed some light on the peculiar mechanism of the COVID-19 coagulopathy and better understanding of its pathophysiology, which may pave the way for novel therapeutic and/or preventive measures to prevent this potentially fatal complication• Materials and Methodology This study is a cross-sectional prospective observational study comparing COVID-19 patients confirmed by positive real-time polymerase chain reaction rt-PCR test, Roche Light Cycler® 480, of nasopharyngeal swabs, and non-COVID-19 patients admitted at King Khalid University Hospital, Riyadh, Saudi Arabia, between October 2020 and December 2020. Informed consent was obtained from all patients or their next of kin for reviewing their electronic medical records and collection of blood samples for the laboratory coagulation tests. The study was conducted in accordance with the Declaration of Helsinki. The study was approved by the Institutional Review Board of the College of Medicine-King Saud University, clinical trial number E-20-5099. Patient Selection The study included patients aged 18–80 years. We excluded incompetent or mentally disabled patients, oncology patients, pregnant or lactating women, patients known to have nephrotic syndrome and liver cirrhosis, and patients recently diagnosed with venous thromboembolism (<3 months) and those on anticoagulants. For the control patients (non-COVID-19) two negative screening rt-PCR test and diagnosis of community-acquired pneumonia (ATS definition) was required for enrolment.19 Demographic and clinical data were collected from the patients’ electronic charts and recorded in a data entry form. These included age, sex, basal metabolic rate (BMI), smoking, comorbidities, medication, and clinical presentation for COVID-19. The metrics for all the baseline laboratory investigations were collected from the system (HbA1C, D-dimer, CBC with differential count, serum ferritin, LDH, Cr, BUN, AST, ALT, Albumin, Bilirubin LDH and CRP). Using a citrated tube, blood samples for natural coagulation factors inhibitors (Protein C, S, Antithrombin (AT) III) were extracted by the attending nurse, within 24 hours of admission, for both COVID-19 and non-COVID-19 patients. Samples were then transferred to Hematopathology Laboratory at King Khalid University Hospital. Coagulation Tests The performed assays included PT, aPTT, fibrinogen, D-dimer, quantification of coagulation FVIII, and physiological inhibitor proteins (protein C, free protein S, and AT). The PT, aPTT, and plasma fibrinogen assays were determined on the NeoPTimal using STA®, PTT A ⑤, Liquid FIB respectively and D-Dimer assay on the Liatest® D-Di PLUS. The Protein S, Protein C, antithrombin assays were determined on the Staclot, Stachrom, Stachrom ATIII STA®, respectively. The ristocetin cofactor activity of vWF-Rco was determined by vWF: RCo and vWF: Ag using Liatest ® vWF: Ag STA®. Statistical Analysis For descriptive and inferential statistical data analyses, Statistical Package for Social Sciences software, version 25.0 (IBM SPSS Inc., Chicago, IL), was used. Both descriptive and inferential statistics involving the Chi-square test and T-independent Test were used to present the results. For each test, a p-value of less than 0.05 was considered statistically significant. Multiple logistic regression analysis and ROC curves were used to identify the independent variable. Results Fifty-four (66.7% males) consecutive COVID-19 patients and 24 (59% males) non-COVID-19 controls were enrolled in the study, from October 2020 till December 2020. The control group patients were diagnosed with community-acquired pneumonia, and 6 of them had acute decompensated heart failure. Seven patients (7.4%) of COVID-19 patients died, 2 patients developed PE and one patient DVT during hospitalization. The severity of Infection with Covid 19 was moderate in 15 patients, severe in 20 patients who required high flow oxygen or CPAP. Out of nineteen patients (35%) admitted to ICU, seven were put on mechanical ventilation (37%), and eight patients received anti-IL-6 (tocilizumab) therapy. Blood group O positive was the predominant ABO phenotype in both Covid-19 and non-COVID-19 patients, 56% and 48%, respectively. COVID-19 patients were significantly older than non-COVID-19 patients (57.7 + 14.2 years vs 50 ±19.8 years, p=0.005) and were more obese (BMI = 31.3 ±7.5 vs 25.7 ±6.9 kg/m2, P=0.003). Their mean Glycosylated Hb (HbA1C) was 7.69±2.1% (Table 1). Thirty-one patients (57%) of Covid-19 patients had type2DM and were on anti-hyperglycemic drugs, while 24 patients (44.4%) were hypertensive There were more smokers in the control group compared to the COVID-19 group (Table 2). There was no difference in comorbid conditions between the COVID-19 and non-COVID-19 groups apart from chronic lung disease, which was more common in the COVID-19 group (18.5% vs 0%, p=0.024) (Table 3). Forty-nine patients (90.7%) of COVID-19 patients versus 18 patients (75%) of controls received LMWH, enoxaparin for VTE prophylaxis, but the difference was not statistically significant (p=0.065). Additionally, the use of antiplatelets was similar among the 2 groups (22.2% vs 33.3%, p=0.3)(Table 3) Table 1 The Laboratory Result Values of COVID-19 Patients and Control Subjects Table 2 Demographic Profile of Study Participants Table 3 Comparison of Co-Morbid Conditions Between (COVID-19 Patients and Control Individuals) Laboratory Results Plasma fibrinogen was significantly higher in COVID-19 patients compared to controls (5.9 ±1.5 vs 3.9 ±1.57, p=0.000). There was no statistically significant difference in the level of proteins C, S, ATIII between the two groups. Similarly, the level of FVIII, although it was elevated in both groups high, it did not differ significantly between the 2 two groups (196.8 ±83.3% vs 227.4±82.9%, p=0.138). However, the level of factor vWF AG was statistically higher in COVID-19 patients (276.7 ±91.01 vs 184.7 ±89.4, p=0.0001) (Table 1). There was a trend towards increased vWF activity in Covid-19 patients, but this did not reach statistical significance, probably due to the small sample size (191,5.31±68,8.18% vs 177.1 ±64.5%, p=0.08). The level of clotting FVIII was increased in COVID-19 as well as in non-COVID-19 patients, with no significant difference between the two groups (p=0.138). There was significant thrombocytopenia and lymphopenia in the COVID-19 group, but there were no differences found in coagulation tests PT, aPTT, and D-dimers levels (Table 1). Inflammatory markers CRP, Ferritin in, and LDH were highly elevated in both COVID-19 and non-COVID-19 patients, but there was no statistical difference between both COVID-19 and non-COVID-19 patients (Table 1). In the multivariate logistic regression analysis of the laboratory values, high fibrinogen and vWF: AG levels were the 2 independent variables found in COVID-19 patients (Table 4). Plasma fibrinogen (OR = 2.552; 95% CI= 1.2835.077; P <0.05) and vWF Ag (OR = 1.011; 95%) COVID-19 patients were used to generate ROC curves (Figure 1). The area under the ROC curve of 0.0.652 for age (P >0.05), of 0.738 for BMI (P <0.05), of 0.678 for smoking (P <0.05), of 0.309 for sex (P <0.05), of 0.202 for lymphopenia (P 5), of 0.797 for Hg (P <0.05), of 0.404 for PT (P <0.05), of 0.862 for fibrinogen (P < 0.05) and of 0.795 for VWF Ag (P <0.05) (Figure 1). Table 4 Multivariate Logistic Regression Analysis of the Laboratory Result Values Obtained from COVID-19 Patients and Control Figure 1 ROC curves for multivariate logistic regression models of significant variables among COVID-19-patients. Discussion This study investigated some of the markers of endothelial dysfunction, coagulation factors, and level of natural anticoagulants early in the course of COVID-19 infection in comparison to non-COVID-19 patients admitted with community-acquired pneumonia CAP during the same time period. We found that the level of vWF Ag, which is a marker of endothelial injury, was significantly higher in COVID-19 patients than in bacterial infections. Its release following SARS-CoV-2 infection of endothelial cells leads to platelet activation and increased levels of FVIII. We also found an Increased level of D-dimer and fibrinogen early in COVID-19 infection. Our findings highlight the important role of endotheliitis in COVID-19 coagulopathy. The high level of vWF Ag and activity may indicate that endothelial stimulation has taken place very early in the course of COVID-19, resulting in the release of vWF from the endothelium. This process is mediated by ACE2 receptors for SAR-Cov-2 on the surface of endothelial cells20 and contributes to the upregulation of fibrinogen and other procoagulants. This goes in parallel with the increase in the inflammatory markers IL6, ferritin, LDH. CRP and suggests that VWF can be a predictive marker of severe infection.21,39 The direct infection of the endothelial cells also leads to platelet activation and increased levels of VWF and FVIII, all of which contribute to thrombin generation and fibrin clot formation.22 The resultant endothelial cell activation can, to a great extent, explain the pulmonary microvascular thrombosis found in post-mortem examination of deceased patients with COVID-19,23,24 The level of FVIII in this study cohort of COVID-19 patients was increased early in the disease and the platelet count was mildly reduced. Interestingly, the levels of natural anticoagulants (Pr C, S, ATIII) in COVID-19 patients were low normal but were not different from that found in patients with non-COVID-19 patients with CAP. This could indicate that depletion of natural anticoagulants occurs in both bacterial and viral infection at a later stage. In addition, this study found that biomarkers of coagulation (such as D-dimer, fibrinogen, platelet count) were affected early in the COVID-19 infection. Previous studies reported that D-dimer could be used to differentiate between COVID-19 patients with severe versus mild disease.22,25 A cut-off value of D-dimer of ≥2 µg/mL (fourfold increase) within 24 hours after hospital admission was reported by Zhang et al to predict in-hospital mortality with a sensitivity of 92.3% and a specificity of 83.3%.26 Of note, the two study groups were not different in the anticoagulant agent used for VTE prophylaxis (Table 3); therefore, the changes noted in D-dimer, fibrinogen and coagulation factors were not related to the type of anticoagulant agent. The increase in fibrinogen noticed early in COVID-19 infection helps differentiate bacterial sepsis or DIC from COVID-19 induced coagulopathy.27 Besides, the associated thrombocytopenia and prolonged activated partial thromboplastin time tend to be mild.18 This supports the theory that arterial thrombosis in COVID-19 is the result of direct endotheliitis caused by SARS-CoV-2 infection of endothelial cells through the two receptors of angiotensin-converting enzyme which results in disseminated microthrombosis, reactive endotheliitis and release of von Willebrand (vWF) multimers.18,39 This seems to be peculiar for COVID-19 and not shared with other viruses that present with decreased plasma fibrinogen concentrations, such as Ebola or Dengue, responsible for hemorrhagic fever and associated with the hypercoagulable state.28 In this study, the lymphocyte count of COVID-1919 pts was statistically lower than non-COVID-19 and occurred early in the disease. This is in agreement with previous studies that reported lymphopenia in 70.3% of hospitalized COVID-19 patients29 and can be considered as a biomarker of adaptive immune response and was found to be associated with COVID-19 severity.30 Limitations of This Study Including the small sample size and being a single-center study, other inflammatory markers, eg, ferritin.IL 6 and procalcitonin were not compared among the two groups. Future studies in a larger number of patients are needed to confirm our findings and probably try to identify other soluble and cellular markers of early endothelial derangement. This will help to further reveal the role of endotheliitis in the procoagulant mechanism of SARs-cov2 infection, eg, plasma VWF propeptide (VWF pp). Conclusion Endothelial injury activation markers are increased early in COVID-19 infection, which is peculiar to COVID-19. The levels of VWF-Ag and fibrinogen are higher in COVID-19 infection than in non-COVID-19 bacterial infections. We probably need to target endothelial injury in early COVID-19 to halt the activation of the coagulation system and consumption of natural anticoagulants and triggering of inflammatory response. VWF Ag can be used as a biomarker for endothelial injury in COVID-19 early in the course of infection and may play a role as a prognostic indicator as demonstrated in other recent studies. Ethics Approval and Consent to Participate The research proposal for this study was approved by the Institutional Review Board (IRB) of the King Saud University, Riyadh Saudi Arabia (IRB Approval Project No. E-205099) for human studies. Informed consents were obtained from the subjects or authorized family representatives with strict confidentiality of information gathered. The study was conducted in accordance with the Declaration of Helsinki. Acknowledgments The authors are grateful to the College of Medicine Research centre and Deanship of Scientific Research, King Saud University (KSU), Riyadh; Saudi Arabia for support and funding. Funding This study was supported and funded by the College of Medicine Research Centre CMRC and the Deanship of Scientific Research of King Saud University, Riyadh, Saudi Arabia. Disclosure The authors of this paper have no conflicts of interest, including specific financial interests, relationships, and/or affiliations relevant to the subject matter or materials included.
  8. It is your choice whether you get the vaccine. The vaccine produces an immune response. Some people refer to the headaches, arm ache, temperature, tiredness, etc, that some people experience as side effects but in reality this is what you want... it means your body has noticed the (inactive) virus and is responding to it. If you look at the statistics for the number of positive cases detected through testing (see Worldometer) the US has confirmed 34 million cases in a population of 332 million. So roughly 1 in 10 people have been infected. Of these 614,000 did not survive. That works out as a 1.8% fatality rate. That doesn’t include those with long covid symptoms. If you choose not to be vaccinated, are you comfortable with a 1 in 55 chance of death? …bearing in mind there are 5 million active cases among fellow citizens that could lead to an infection (1 in 66 currently have a covid infection). The alternative is to get the vaccine. It is approximately 94% effective. That improves your odds to 1 in 5,170. So it's not perfect, some people will not make it either way. The 1 in 500,000 possibility of a rare side effect from the vaccine itself only tweaks that number by 0.01 - making it 1 in 5,170.01 Put that into context of a small town with say 20,000 population. With vaccine 4 deaths. Without vaccine 363 deaths. Another benefit of the vaccine, apart from improving your odds of surviving the pandemic, is to reduce transmission. So your own vaccination helps to protect friends and family. It also reduces the numbers of patients in hospitals. If you become unwell the hospital can offer treatment. If it is full then more people could die due to lack of medical care. A full hospital reduces that 1 in 55 figure. In my personal experience I had a strong immune response to the first dose of Astra Zenica. I had a migraine (which I suffer from anyway), temperature for a day, and my arm ached for 2 weeks. When I had my second dose my arm ached slightly for a week. You have to ask yourself, if it is the same drug and the same person, then why didn’t it produce the same ‘side effects’ ... of course the answer is my body had developed my immune defence and was ready second time around. It means it’s ready to deal with the actual virus if I come into contact with it. From our Facebook Group with 1600 members some people have shared concerns about the combination of PSD with vaccines and with Covid. Nobody has reported any clotting issues as a result of the vaccine. Some people have reported they contracted Covid and recovered. None of the vaccine makers have listed PSD as a contradindication but a few other health conditions may apply so you will need to ask your doctor for your personal circumstances. Nobody is claiming that the vaccine makes you safe, only safer. How you choose to balance the choice of getting, or not getting, the vaccine is up to you. (As per the footer… Disclaimer: For your own health and safety you should always seek the advice of a qualified medical practitioner and not act on information published on this web site. No responsibility can be accepted for the content or absence of content published on this site for any reason.)
  9. I have Protein S Deficiency with a history of DVT and PE, and have been taking warfarin for around 30 years. My first wisdom tooth was removed in 2006, another in 2010, my third in 2016, and my last yesterday. I previously reported about my first extraction here and thought it might be worth an update to share some new details. This dentist required an INR of between 2.0 and 4.0 with a test taken in the previous 2 days. The advice appears to have changed over the years because it should be within this range under normal circumstances, and previously I was asked to reduce my INR to a lower level. I am fortunate to have a relatively stable INR so even though I wasn’t specifically asked I intentionally skipped two days of warfarin and this brought my INR down from 3.5 to 2.2. After surgery I went back on my normal dose and will have my INR rechecked in about a week’s time. The wisdom tooth that was removed was a lower molar, which the dentist explained was usually physically harder to remove than upper molars due to the root structure. The hole was then packed with material to help it heal and dissolvable stitches to keep it in place. Apart from the risk of post-surgical bleeding I was treated the same way as anyone else. However due to my warfarin I was referred by my regular dentist to one that specialises in extractions and I feel his expertise made all the difference. I had a rough experience on my extraction in 2010 with a regular dentist and so if anyone else is considering wisdom tooth extraction my advice would be to ask your ‘general’ dentist whether you can be referred to one that specialises in removing teeth. I just think you’ll have a better experience and less bruising.
  10. Thrombosis can cause depletion of Protein S. In the case of Covid-19 the virus causes inflammation of the lungs, and subsequent damage causes clotting. The virus itself doesn’t cause the clots directly. To be reliable the screening for your diagnosis should have been based on blood samples taken a couple of months after your thrombosis, when your natural levels would have recovered.
  11. The eligibility criteria for joining the UK Royal Navy and Royal Marines includes age, height, weight, tattoos and piercings, eye sight, pregnancy and minimum fitness targets. The current medical restrictions include ‘any bleeding disorder or abnormality of blood clotting’ as set out in the following PDF document. https://www.royalnavy.mod.uk/-/media/files/cnr-pdfs/20201127eligibility-formworduc15122020update.pdf
  12. Synchronous presentation of COVID‐19 pneumonia and pulmonary embolism Farid Poursadegh, Najmeh Davoudian, Mahnaz Mozdourian, Fahimeh Abdollahi First published: 27 January 2021, https://doi.org/10.1002/ccr3.3870 *** Simultaneous diagnosis of COVID‐19 pneumonia and pulmonary embolism without any deep vein thrombosis nor predisposing hypercoagulable states was observed. Therefore, patients with COVID‐19 pneumonia who suffer from worsening of the clinical respiratory symptoms, after the beginning of the treatment, should be evaluated for pulmonary embolism using CT angiography, if safe. *** 3 DISCUSSION Previous studies evidenced that SARS‐CoV‐2 stimulates the coagulation pathway, resulting in abnormal coagulation parameters and endothelial dysfunction. These make the important factor of increased D‐dimer level a poor prognostic factor for patients with COVID‐19.10, 11 Also, the biopsy examination of patients who died with the diagnosis of COVID‐19 has revealed histomorphologically diffuse alveolar damage confirming the COVID‐19–induced coagulopathy. In our case, as a patient with COVID‐19 presented with pulmonary embolism without any previous predisposing hypercoagulable risk factor, the level of protein C and protein S had decreased with a considerable rise in D‐dimer. In another study by Panigada et. al., opposite results have been reported. By assessing 24 COVID‐19 patients in the intensive care unit, they have reported an increase in the level of protein C and a marginal decrease in the level of protein S. The kinetics and robustness of the immune response to COVID‐19 are yet to be known. Recent studies show that respiratory failure in COVID‐19 patients is not only caused by respiratory distress but also microscopic clot formation processes. This finding may be a clue to a better understanding of the treatment of these patients. There is a strong relationship between the levels of D‐dimer molecule and disease progression and CT scan findings in these patients, which indicates the cause of venous clots in them. Some studies also show that there is not a direct relationship between D‐dimer levels and disease severity. Accordingly, imaging studies have confirmed that COVID‐19 syndrome is an inflammatory, clotting‐inflammatory process that negatively affects lung function, and in later stages, affects other organs in the body.
  13. Instagram celebrity Mrs Hinch has Protein S deficiency and Factor V Leiden, in the The Sun news. Mrs Hinch previously opened up about her health problems in her book, Hinch Yourself Happy. She was forced to miss her honeymoon a few years ago after falling ill with a blood clot, suffering back pain and a swollen leg, which left her unable to stand. https://www.thesun.co.uk/fabulous/12611235/mrs-hinch-blood-condition-bruises/
  14. Rory Bremner has revealed in a Daily Mail interview that he and his brother have Protein S Deficiency... ‘My Dad died of cancer in 1979 when he was 72 and I was 18. My older brother Nigel has protein S deficiency, a blood clotting disorder. A year ago, I had a curious itchy rash on my shin and my wife thought a clot was developing. Sure enough, I also have protein S deficiency. It can only be treated with anticoagulant medication.’ Interview appears below this article... https://www.dailymail.co.uk/health/article-9185645/Why-taking-afternoon-nap-not-dozy-idea.html
  15. It would be best for you to speak to your doctor and ask for a referral to a haematologist for your longer term healthcare options. They will understand how to obtain a test result that gives an accurate understanding of whether you have a natural deficiency in your Protein C or Protein S levels. Unfortunately test results can be unreliable if they are taken at the same time as the thrombosis or soon after, so you need to have a recovery period and let things settle down before testing takes place. A haematologist will usually look into family history and screening of your relatives too... for example if mother and father can be tested this will let them know if there is a hereditary cause and their tests won't be influenced by any recent thrombosis.
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