scholarly journals Increased adhesive properties of neutrophils in sickle cell disease may be reversed by pharmacological nitric oxide donation

Haematologica ◽  
2008 ◽  
Vol 93 (4) ◽  
pp. 605-609 ◽  
Author(s):  
A. A. Canalli ◽  
C. F. Franco-Penteado ◽  
S. T.O. Saad ◽  
N. Conran ◽  
F. F. Costa
Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 959-959
Author(s):  
Michael Tarasev ◽  
Marta Ferranti ◽  
Cidney Allen ◽  
Xiufeng Gao ◽  
Kayla Topping ◽  
...  

Abstract Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause severe vascular complications associated with endothelial dysfunction and systemic inflammation. COVID19-specific IgG are detectable within a week of infection. Long COVID-19 has been described in patients continuing to exhibit symptoms after the virus is no longer detectable in the respiratory secretions, including fatigue, dyspnea, headache, and brain fog. The recent FAIR Health study reviewed a total of 1,959,982 COVID-19 patients for the prevalence of long COVID symptoms and reported that 23.2% had at least one post-COVID symptom [1]. The underlying biologic mechanisms of long COVID remain unclear, thus treatments are limited to symptomatic relief and supportive care. Many long COVID symptoms are consistent with systemic inflammation and impaired oxygen delivery observed in individuals with sickle cell disease (SCD), in turn associated with elevated blood cell adhesion and decreased red blood cell (RBC) stability. The aim of this study was to determine if deleterious changes in in blood cell properties related to adhesion and membrane stability under stress can be associated with the symptoms of long COVID-19. In this work we evaluated 7 SCD patients that were diagnosed with SARS-Cov-2 and tracked their recovery using semiquantitative IgG and blood cell function assays. Methods: Blood samples were collected by the Foundation for Sickle Cell Disease (SCD) Research from SCD (homozygous SS, n=6) patients coming for regular or urgent clinic visit with SARS-CoV-2 serological and blood cell functions tests performed per the standard of care. Semiquantitative IgG assay was performed using DXi-80 (Beckman Coulter). Flow adhesion of whole blood to VCAM-1 (FA-WB-VCAM)and P-Selectin (FA-WB-Psel) substrates were determined by counting the cells that remain adherent in a microfluidics channel after perfusion with whole blood 1:1 diluted with HBSS buffer and washed by reversed flow at 1 dyne/cm 2. Red blood cell mechanical fragility (RBC MF) was measured as hemolysis induced by an oscillating cylindrical magnet with periodic non-invasive probing of cell-free hemoglobin fraction. Six individuals with SCD recovering from SARS-Cov-2 with biomarker data available both before and for more than 3 months after the infection (179±62 days) were included in the study. Results: IgG levels varied from less than 0.1 to 37, with positive values being defined as IgG > 1. The median estimated half-life of IgG decline was 53 days ranging from 25 to 90 days (the last, for the hospitalized patient). Averaged for IgG positive (IgG+) and IgG negative (IgG-) conditions, combining pre- and post-infection IgG- conditions, values of patient hemoglobin (Hb), FA-WB-VCAM, FA-WB-Psel, and RBC MF cell properties lacked statistical significance (under both a paired t-test and population statistics). Hb levels remained essentially unchanged regardless of the time from infection or IgG status. However, FA-WB-VCAM, FA-WB-Psel, and RBC MF were all significantly elevated after SARS-Cov-2 seroconversion and remained elevated despite declining IgG levels (e.g., Fig. 1). These increases in biomarker values were statistically significant for both FA-WB-VCAM and RBC MF, and were approaching significance for FA-WB-Psel (p<0065). These increases were highly patient-specific with potential return to pe-infection values observed in some cases at about 5-6 months after the infection. A qualitative review of the medical records indicated a new subjective report of fatigue in 5 of 6 patients. Longer observations are required to determine if abnormal blood cell adhesive properties and RBC membrane instability are mechanisms of long-COVID-19 pathophysiology. Conclusions: Whole blood adhesion to both p-selectin and VCAM-1 as well as RBC membrane stability can be significantly impaired in convalescent SARS-Cov-2 patients suggesting an association with long COVID-19. New and emerging treatments that modify whole blood adhesive properties and RBC membrane stability should be investigated for their potential to accelerated recovery from long COVID-19. Health F. A Detailed Study of Patients with Long-Haul COVID: An Analysis of Private Healthcare Claims; White Paper. June 15, 2021 Disclosures Tarasev: Functional Fluidics: Current holder of stock options in a privately-held company. Ferranti: Functional Fluidics: Current holder of stock options in a privately-held company. Allen: Functional Fluidics: Current Employment. Gao: Functional Fluidics: Current Employment. Topping: Functional Fluidics: Current Employment. Ferranti: Functional Fluidics: Current Employment. Makinde-Odesola: Functional Fluidics: Other: conduct research for academic program. Hines: Functional Fluidics: Current holder of stock options in a privately-held company.


1995 ◽  
Vol 91 (4) ◽  
pp. 834-837 ◽  
Author(s):  
David C. Rees ◽  
Paul Cervi ◽  
David Grimwade ◽  
Aisling O'Driscoll ◽  
Malcolm Hamilton ◽  
...  

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Katherine C Wood ◽  
Heidi M Schmidt ◽  
Scott Hahn ◽  
Mehdi Nouraie ◽  
Mara Carreno ◽  
...  

Introduction: Stroke and silent infarcts are serious complications of sickle cell disease (SCD), occurring frequently in children. Decreased nitric oxide bioavailability and responsiveness contribute to neurovascular disease. Cytochrome b5 reductase 3 (Cyb5R3) is a heme iron reductase that reduces oxidized soluble guanylate cyclase heme iron (Fe 3+ --> Fe 2+ ) to preserve nitric oxide signaling. A loss-of-function Cyb5R3 missense variant (T117S) occurs with high frequency (0.23 minor allele) in persons of African ancestry. Hypothesis: We hypothesized that impaired reductase function of T117S Cyb5R3 exacerbates brain damage after ischemic stroke in SCD. Methods: Bone marrow transplant was used to create male SCD mice with wild type (SS/WT) or T117S (SS/T117S) Cyb5R3. Blood was sampled before and after middle cerebral artery occlusion (55 minutes occlusion, 48 hours reperfusion). Infarct volume (IV) was determined by 2,3,5-triphenyltetrazolium chloride. Intravascular hemolysis and correlation (Pearson’s R) of hematology changes with IV were determined. Baseline Walk-PHaSST (NCT00492531) data were analyzed for stroke occurrence. Results: Brain IV (63 vs 27 cm 3 , P=0.003) and mortality (3/6 vs 0/8) were greater in SS/T117S vs SS/WT. Red blood cells, hemoglobin and hematocrit declined as IV increased. Plasma oxyhemoglobin increased in parallel with IV (r = 0.74, P=0.09). There were different signatures to hematologic changes that occurred with IV in SCD. Relative to wild type, T117S contracted the erythroid compartment (red blood cell: -13% vs 13%, P=0.003; hematocrit: -20% vs 1%, P=0.008; hemoglobin: -18% vs 2%, P=0.007). Mean platelet volume correlated with IV in SS/T117S (r = 0.87, P=0.06), while the inverse occurred in SS/WT (r = -0.63, P=0.09) Monocytes increased in parallel with IV in SS/T117S (r = 0.73, P=0.16), but followed the opposite trajectory in SS/WT (r = -0.77, P=0.04). WalkPHaSST participants with T117S Cyb5R3 self-reported more ischemic stroke (7.4% vs 5.1%) relative to wild type. Conclusion: Cyb5R3 is an important modifier of the evolution and outcome of ischemic brain injury in SCD and its hematologic consequences. Our findings indicate a bidirectional relationship between stroke and anemia in SCD that may axially turn on Cyb5R3 activity.


2020 ◽  
Vol 34 (7) ◽  
Author(s):  
Charles Antwi‐Boasiako ◽  
Gifty Boatemaah Dankwah ◽  
Robert Aryee ◽  
Charles Hayfron‐Benjamin ◽  
George Aboagye ◽  
...  

2000 ◽  
Vol 279 (6) ◽  
pp. R1949-R1955 ◽  
Author(s):  
K. A. Nath ◽  
V. Shah ◽  
J. J. Haggard ◽  
A. J. Croatt ◽  
L. A. Smith ◽  
...  

We investigated a transgenic mouse model of sickle cell disease, homozygous for deletion of mouse β-globin and containing transgenes for human βSand βS-antillesglobins linked to the transgene for human α-globin. In these mice, basal cGMP production in aortic rings is increased, whereas relaxation to an endothelium-dependent vasodilator, A-23187, is impaired. In contrast, aortic expression of endothelial nitric oxide synthase (NOS) is unaltered in sickle mice, whereas expression of inducible NOS is not detected in either group; plasma nitrate/nitrite concentrations and NOS activity are similar in both groups. Increased cGMP may reflect the stimulatory effect of peroxides (an activator of guanylate cyclase), because lipid peroxidation is increased in aortae and in plasma in sickle mice. Despite increased vascular cGMP levels in sickle mice, conscious systolic blood pressure is comparable to that of aged-matched controls; sickle mice, however, evince a greater rise in systolic blood pressure in response to nitro-l-arginine methyl ester, an inhibitor of NOS. Systemic concentrations of the vasoconstrictive oxidative product 8-isoprostane are increased in sickle mice. We conclude that vascular responses are altered in this transgenic sickle mouse and are accompanied by increased lipid peroxidation and production of cGMP; we suggest that oxidant-inducible vasoconstrictor systems such as isoprostanes may oppose nitric oxide-dependent and nitric oxide-independent mechanisms of vasodilatation in this transgenic sickle mouse. Destabilization of the vasoactive balance in the sickle vasculature by clinically relevant states may predispose to vasoocclusive disease.


Blood ◽  
1997 ◽  
Vol 89 (12) ◽  
pp. 4591-4599 ◽  
Author(s):  
James A. French ◽  
Dermot Kenny ◽  
J. Paul Scott ◽  
Raymond G. Hoffmann ◽  
James D. Wood ◽  
...  

Abstract The etiology of stroke in sickle cell disease is unclear, but may involve abnormal red blood cell (RBC) adhesion to the vascular endothelium and altered vasomotor tone regulation. Therefore, we examined both the adhesion of sickle (SS)-RBCs to cerebral microvessels and the effect of SS-RBCs on cerebral blood flow when the nitric oxide (NO) pathway was inhibited. The effect of SS-RBCs was studied in the rat cerebral microcirculation using either a cranial window for direct visualization of infused RBCs or laser Doppler flowmetry (LDF ) to measure RBC flow. When fluorescently labeled human RBCs were infused into rats, SS-RBCs had increased adhesion to rat cerebral microvessels compared with control AA-RBCs (P = .01). Next, washed SS-RBCs or AA-RBCs were infused into rats prepared with LDF probes after pretreatment (40 mg/kg intravenously) with the NO synthase inhibitor, N-ω-nitro-L-arginine methyl ester (L-NAME), or the control isomer, D-NAME. In 9 rats treated with systemic L-NAME and SS-RBCs, 5 of 9 experienced a significant decrease in LDF and died within 30 minutes after the RBC infusion (P = .0012). In contrast, all control groups completed the experiment with stable LDF and hemodynamics. Four rats received a localized superfusion of L-NAME (1 mmol/L) through the cranial window followed by infusion of SS-RBCs. Total cessation of flow in all observed cerebral microvessels occurred in 3 of 4 rats within 15 minutes after infusion of SS-RBCs. We conclude that the NO pathway is critical in maintaining cerebral blood flow in the presence of SS-RBCs in this rat model. In addition, the enhanced adhesion of SS-RBCs to rat brain microvessels may contribute to cerebral vaso-occlusion either directly, by disrupting blood flow, or indirectly, by disturbing the vascular endothelium.


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