In a recent study posted to the medRxiv* preprint server, researchers assessed the infectious capacity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in plasma and red blood cells (RBCs), ascertaining its role in SARS-CoV-2 dissemination.
Background
Coronavirus disease 2019 (COVID-19) is a multisystemic illness affecting respiratory and non-respiratory organs. Studies have reported that SARS-CoV-2 infections are related to several hematological diseases; however, data on how SARS-CoV-2 can navigate to different tissues are limited.
About the study
In the present study, researchers investigated the association between viral organotropism and clinical manifestations employing the prototypical CoV in the naturally occurring host, the murine hepatitis virus (MHV)-A59 model.
Quantitative reverse-transcription-polymerase chain reaction (RT-qPCR) and viral infectivity analysis were performed. The plasma and RBC-enriched fractions were compared.
Further, in silico computational docking analysis was performed to investigate the potential interaction between heme (and heme-associated molecules) and murine hepatitis virus spike protein.
Sera and nasopharyngeal swabs of 37 RT-qPCR-confirmed COVID-19 patients were obtained. SARS-CoV-2 ribonucleic acid (RNA) was extracted to qualitatively and quantitatively detect SARS-CoV-2.
Kidney, heart, lung, and liver tissues were obtained from autopsies performed on eight individuals with COVID-19-associated deaths. BALB/cJ mice were used for the in vivo experiments, infected with MHV by intraperitoneal injection, and treated with hemin and chloroquine, individually and in combination.
Murine lung, liver, heart, kidney, spleen, pancreas, and brain tissues were obtained for RT-qPCR and infectious SARS-CoV-2 particle evaluation. Blood samples were obtained for biochemistry-related and hematological assessments before and after infection.
Plaque assays were performed to assess viable SARS-CoV-2 particles. The team compared the results with real-world information on SARS-CoV-2-positive individuals, including autopsies of individuals deceased due to COVID-19.
Results
The mean age of the participants was 56 years, and 68% (n=19) were men. SARS-COV-2 ribonucleic acid was detected in the sera of 23% of the patients, whereas all individuals had multiple SARS-CoV-2-positive nasopharyngeal swabs.
Of note, SARS-CoV-2 ribonucleic acid was detected in the kidneys and heart of individuals, in addition to in the lungs of individuals deceased due to COVID-19.
SARS-CoV-2 infectivity and RT-qPCR findings showed SARS-CoV-2 ribonucleic acid and infectious SARS-CoV-2 particles’ presence in several organs and tissues, including the lung, liver, heart, brain, spleen, kidney, blood, and pancreas.
Greater viral loads, monocyte proportions, neutrophil proportions, platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) were observed post-infection, with lowered erythrocyte count, hemoglobin levels, hematocrit, leukocyte counts, lymphocyte proportion, and platelet counts among infected mice.
Of note, combining chloroquine and hemin treatment attenuated the clinical presentation of the infection. Computational docking showed that heme could bind with the murine hepatitis virus spike protein similarly to SARS-CoV-2. SARS-CoV-2 RNA was detected at high viral loads in all pulmonary samples, but in only 14% of cardiac samples, and to some extent, in the kidneys, at low viral loads.
MHV infection significantly reduced the weight of infected mice, and SARS-CoV-2 RNA was most abundant in mice’s lungs, liver, spleen, and brain. SARS-CoV-2 particles, obtained from various organs, were infectious, as determined by the viral infectivity assays.
Hepatic parameters, including total protein, globulin, and albumin, were lowered, whereas aspartate aminotransferase (AST) and alanine transaminase (ALT) levels rose post-infection. Concerning the kidneys, the blood urea nitrogen (BUN) level increased significantly following infection.
Among the murine animals infected with MHV, the weight of the heart was lower, whereas that of the spleen was greater than in the control mice. MHV was primarily detected in the RBC fraction and negatively affected the blood biochemistry.
Viral loads and viral titers were greater in the erythrocyte-enriched fraction than in the plasma-enriched blood fraction. Hemin enhanced CoV RNA abundance systemically and increased SARS-CoV-2 particles in erythrocytes.
Combined hemin and chloroquine treatment reversed the enhanced infection phenotype observed with hemin treatment alone. Of interest, RT-qPCR findings indicated that hemin-treated and murine animals infected with MHV had significantly greater SARS-CoV-2 RNA abundance in the lung, liver, kidneys, and heart, with slightly greater abundance in the brain than the uninfected and untreated mice.
The combined treatment reversed coV-induced effects on hematological parameters. The findings indicated SARS-CoV-2 presence in the blood compartment, in RBC and plasma, elevation in viral particles from both fractions under hemin treatment, and the counteracting effect when both drugs, hemin, and chloroquine, were administered.
Conclusion
Overall, the study findings showed multiple organ involvement combined with mechanisms of RBC and hematological dysregulation that may favor SARS-CoV-2 infection and shed light on the probable implications of infectious SARS-CoV-2 particles presence in erythrocytes of SARS-CoV-2-positive individuals.
The study findings indicated possible ways SARS-CoV-2 may induce hemolysis, sequestering heme and hitch-hicking its way into multiple organs, supporting the involvement of multiple organs in COVID-19 via interaction with erythrocyte hemoproteins.
News
Baffling Scientists for Centuries: New Study Unravels Mystery of Static Electricity
ISTA physicists demonstrate that contact electrification depends on the contact history of materials. For centuries, static electricity has intrigued and perplexed scientists. Now, researchers from the Waitukaitis group at the Institute of Science and [...]
Tumor “Stickiness” – Scientists Develop Potential New Way To Predict Cancer’s Spread
UC San Diego researchers have developed a device that predicts breast cancer aggressiveness by measuring tumor cell adhesion. Weakly adherent cells indicate a higher risk of metastasis, especially in early-stage DCIS. This innovation could [...]
Scientists Just Watched Atoms Move for the First Time Using AI
Scientists have developed a groundbreaking AI-driven technique that reveals the hidden movements of nanoparticles, essential in materials science, pharmaceuticals, and electronics. By integrating artificial intelligence with electron microscopy, researchers can now visualize atomic-level changes that were [...]
Scientists Sound Alarm: “Safe” Antibiotic Has Led to an Almost Untreatable Superbug
A recent study reveals that an antibiotic used for liver disease patients may increase their risk of contracting a dangerous superbug. An international team of researchers has discovered that rifaximin, a commonly prescribed antibiotic [...]
Scientists Discover Natural Compound That Stops Cancer Progression
A discovery led by OHSU was made possible by years of study conducted by University of Portland undergraduates. Scientists have discovered a natural compound that can halt a key process involved in the progression [...]
Scientists Just Discovered an RNA That Repairs DNA Damage – And It’s a Game-Changer
Our DNA is constantly under threat — from cell division errors to external factors like sunlight and smoking. Fortunately, cells have intricate repair mechanisms to counteract this damage. Scientists have uncovered a surprising role played by [...]
What Scientists Just Discovered About COVID-19’s Hidden Death Toll
COVID-19 didn’t just claim lives directly—it reshaped mortality patterns worldwide. A major international study found that life expectancy plummeted across most of the 24 analyzed countries, with additional deaths from cardiovascular disease, substance abuse, and mental [...]
Self-Propelled Nanoparticles Improve Immunotherapy for Non-Invasive Bladder Cancer
A study led by Pohang University of Science and Technology (POSTECH) and the Institute for Bioengineering of Catalonia (IBEC) in South Korea details the creation of urea-powered nanomotors that enhance immunotherapy for bladder cancer. The nanomotors [...]
Scientists Develop New System That Produces Drinking Water From Thin Air
UT Austin researchers have developed a biodegradable, biomass-based hydrogel that efficiently extracts drinkable water from the air, offering a scalable, sustainable solution for water access in off-grid communities, emergency relief, and agriculture. Discarded food [...]
AI Unveils Hidden Nanoparticles – A Breakthrough in Early Disease Detection
Deep Nanometry (DNM) is an innovative technique combining high-speed optical detection with AI-driven noise reduction, allowing researchers to find rare nanoparticles like extracellular vesicles (EVs). Since EVs play a role in disease detection, DNM [...]
Inhalable nanoparticles could help treat chronic lung disease
Nanoparticles designed to release antibiotics deep inside the lungs reduced inflammation and improved lung function in mice with symptoms of chronic obstructive pulmonary disease By Grace Wade Delivering medication to the lungs with inhalable nanoparticles [...]
New MRI Study Uncovers Hidden Lung Abnormalities in Children With Long COVID
Long COVID is more than just lingering symptoms—it may have a hidden biological basis that standard medical tests fail to detect. A groundbreaking study using advanced MRI technology has uncovered significant lung abnormalities in [...]
AI Struggles with Abstract Thought: Study Reveals GPT-4’s Limits
While GPT-4 performs well in structured reasoning tasks, a new study shows that its ability to adapt to variations is weak—suggesting AI still lacks true abstract understanding and flexibility in decision-making. Artificial Intelligence (AI), [...]
Turning Off Nerve Signals: Scientists Develop Promising New Pancreatic Cancer Treatment
Pancreatic cancer reprograms nerve cells to fuel its growth, but blocking these connections can shrink tumors and boost treatment effectiveness. Pancreatic cancer is closely linked to the nervous system, according to researchers from the [...]
New human antibody shows promise for Ebola virus treatment
New research led by scientists at La Jolla Institute for Immunology (LJI) reveals the workings of a human antibody called mAb 3A6, which may prove to be an important component for Ebola virus therapeutics. [...]
Early Alzheimer’s Detection Test – Years Before Symptoms Appear
A new biomarker test can detect early-stage tau protein clumping up to a decade before it appears on brain scans, improving early Alzheimer’s diagnosis. Unlike amyloid-beta, tau neurofibrillary tangles are directly linked to cognitive decline. Years [...]
