Enzyme that change a person’s blood type

Blood Type

Blood Type

Scientists have discovered that a particular type of enzyme can cut away antigens in blood types A and B, to make them more like Type O – considered the ‘universal’ blood type, because it’s the only type that can be donated to anyone without the risk of provoking a life-threatening immune response.

The team, from the University of British Columbia of Canada, worked with a family of enzymes called 98 glycoside hydrolase, extracted from a strain of Streptococcus pneumoniae. Over many generations, they were able to engineer a super high-powered enzyme strain that can very effectively snip away blood antigens where previous generations of the enzyme struggled. “A major limitation has always been the efficiency of the enzymes,” one of the team, Stephen Withers, said in a press release. “Impractically large amounts of enzyme were needed.”

Getting the right type of blood when you need it is crucial, and it has to do with the different types of residue that can accumulate the surface of red blood cells. Both blood types A and B have this residue – A has an N-acetylgalactosamine residue, and B has a galactose residue – and Type AB has a mixture of both. Only Blood Type O is free from this residue, which means it can be received by any patient, no matter what type they’re carrying.

Withers and his team managed to create their ‘mutant’ enzyme strain using a technology called directed evolution, which allows them to insert many different types of mutations into the gene that codes for it, and by progressively selecting strains that are the best at snipping away the blood antigens, were able to create an enzyme that’s 170 times more effective at it than its parent strain. They published their results in the Journal of the American Chemical Society.

“The concept is not new, but until now we needed so much of the enzyme to make it work that it was impractical,” said Withers. “Now I’m confident that we can take this a whole lot further.”

While the current enzyme strain is not yet capable of removing 100 percent of the antigens from Blood Types A and B, which is where it needs to get if the researchers want to make any real use of it, the team is confident that they’ll get it there so they can try it out in clinical trials. Even the smallest amount of antigen in donated blood can set off a dangerous immune response in the recipient.

“Given our success so far, we are optimistic that this will work,” says Withers.

Source:  sciencealert.com

Smartphone detects blood for parasites

Blood parasite smartphone1

Blood parasite smartphone

The CellScope system films a drop of blood and an app then automatically analyses any movement in the sample to detect the parasites.

The results, published in Science Translational Medicine, showed the device was successful in small trials in Cameroon.

Experts said it marked a fundamental advance in tropical diseases.

Previous efforts to eradicate two parasitic diseases – river blindness and elephantiasis – have been suspended because the treatment can become fatal in some people.

One treatment, the drug ivermectin, is risky in people with high levels of Loa loa worm – the one that can crawl across the surface of the eye – so people need to be screened first.


The team in the most recent research, at the University of California, Berkeley, and the US National Institutes of Health, used a modified smartphone to automate the process.

A pindrop of blood was collected and loaded into a handheld box. The phone on top then kicked in.

“With one touch of the screen, the device moves the sample, captures video and automatically analyses the images,” said one of the researchers, Prof Daniel Fletcher.

Rather than attempt to identify the shape of the worm, the software in the phone looks for the movement.

Treat or not?

The software predicts the number of Loa loa parasites in the blood and tells the healthcare workers whether they are suitable for drug treatment.

It means very little training is required, while current screening procedures require someone to be skilled in analysing blood samples by eye.

Early trials in Cameroon of the new approach have been successful and there are now plans to test it on 40,000 people.

Prof Fletcher told the BBC News website: “I’m excited, it offers a new higher-tech approach to dealing with very low-tech problems.”

“There are drugs to treat many neglected tropical diseases, these are problems that should be solved, but there is not the technology to identify people who who need the right drugs.”

It is hoped the same idea could be adapted to test for other infections such as TB, malaria and soil-transmitted parasitic worms or helminths, which include roundworm.

‘Fundamental advance’

Prof Simon Brooker from the London School of Hygiene & Tropical Medicine, commented: “I think it’s one of the most fundamental advances in neglected tropical diseases in a long time.”

“In the 21st Century we are using 20th Century technology to diagnose these infections, this brings us into the modern world.

Blood Test to Diagnose Depression

First Blood Test to Diagnose Depression in Adults

First Blood Test to Diagnose Depression in Adults

Test identifies nine blood markers tied to depression; predicts who will benefit from therapy

The first blood test to diagnose major depression in adults has been developed by Northwestern Medicine® scientists, a breakthrough approach that provides the first objective, scientific diagnosis for depression. The test identifies depression by measuring the levels of nine RNA blood markers. RNA molecules are the messengers that interpret the DNA genetic code and carry out its instructions.

The blood test also predicts who will benefit from cognitive behavioral therapy based on the behavior of some of the markers. This will provide the opportunity for more effective, individualized therapy for people with depression.

In addition, the test showed the biological effects of cognitive behavioral therapy, the first measurable, blood-based evidence of the therapy’s success. The levels of markers changed in patients who had the therapy for 18 weeks and were no longer depressed.

“This clearly indicates that you can have a blood-based laboratory test for depression, providing a scientific diagnosis in the same way someone is diagnosed with high blood pressure or high cholesterol,” said Eva Redei, who developed the test and is a professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine. “This test brings mental health diagnosis into the 21st century and offers the first personalized medicine approach to people suffering from depression.”

Redei is co-lead author of the study, which was published Sept. 16 in Translational Psychiatry.

Redei previously developed a blood test that diagnosed depression in adolescents. Most of the markers she identified in the adult depression panel are different from those in depressed adolescents.


Source:  scienceblog.com

Red Blood Cells Take On New Geometry During Clotting

Red Blood Cells Take On Many-Sided Shapes:

Red Blood Cells Take On Many-Sided Shape During Clotting

Red Blood Cells Take On Many-Sided Shape












Red blood cells are real levers of change in body shape, perhaps the most malleable of all cell types , transformation – among other forms – in compressed discs able to pass through capillaries with diameters less than the cell itself blood . While the study of how blood clots John W. contract Weisel , Ph.D. , Professor of Cell and Developmental Biology at the Perelman School of Medicine at the University of Pennsylvania, and his colleagues discovered a new geometry that red blood cells are supposed to when compressed during clot formation .

Although red blood cells were visualized for the first time in the mid-17th century and studied extensively since then , this new study , published online ahead of print in the journal Blood, describes a previously unknown and new function potential of red blood cells . The Penn team found that red blood cells can be compressed into multifaceted structures close together – polyhedral – instead bi – concave , free-flowing form of the disc.

What is more , contrary to expectations , the fibrin and platelet aggregates which form highly clots are mainly employed on the outside of clots , with red blood cells crowded into the clot , while the content of clots are more homogeneous before shrinkage occurs .

Hired clots can form a watertight seal and help prevent vascular obstruction, but confer resistance to penetration of drugs that break down fibrin, the structural component of blood clots , one common treatment option for heart attacks and strokes.

” When I first saw this, he thought :” This can not be biological , ‘”says Weisel . The team first saw the red blood cells shaped polyhedron – when the coagulation process of contraction is studied using a novel MRI technology , with the co -authors of T2 Biosystems, along with co -author Douglas Cines , MD , director of the Coagulation Laboratory and Professor of Pathology and Laboratory Medicine at Penn. They observed a signal indicating tight red blood cells.

The clot network clots are dimensional network of fibers , mainly consisting of the blood protein fibrinogen , which is converted to fibrin during coagulation , and platelets , which aggregate by binding to fibrin once activated . A blood clot must have the proper degree of rigidity and plasticity to stop the flow of blood when tissue is damaged , however , be flexible enough that it does not block the blood flow .

After a clot forms , actin and myosin in platelets initiate the contraction process and cause the clot is reduced to about one third of its original size. This is an important step to stop bleeding , to reduce the blockage in the blood vessel , and to provide a matrix for the migration of cells involved in wound healing . Red blood cells are involved in the contraction process , especially in the venous system , and get pulled by platelets into the clot, blood and the study indicated .

Little is known about the structure of the contracted clots or the role of red blood cells in the contraction process . “We found that the contracted blood clots develop a remarkable structure with a mesh of fibrin and platelet aggregates outside the clot and close packing , tiled matrix of polyhedral erythrocytes compressed inside ,” says Weisel .

The team also saw the same morphology of compacted clots after initiating coagulation activators and also with several clots formed from reconstituted human blood cellular components and blood plasma and mouse . Such matrices polyhedral packing of erythrocytes or polyhedrocytes as researchers dubbed them , were also observed in human arterial thrombi taken from patients who had heart attacks . This form is likely taken up by the red blood cells when contracted or compressed together when platelets clot in order to decrease the volume , surface energy , or the energy of bending , the authors assume .

Cines notes that these findings may have clinical implications . Doctors need to inject tPA as thrombolytic agents to quickly break thrombi , clots that obstruct blood flow , for example, in the coronary arteries to treat a heart attack or arteries leading to the brain to treat stroke. It is well known that thrombi develop time be broken , which is one reason why early intervention resistance is important . The nearly impermeable barrier formed by the red blood cells within contracted clots was observed in the study of the blood can help explain why . Clot contraction could be a target of intervention to prevent the formation of densely packed array polyhedrocytes .

Type 2 diabetes genes and metabolic markers

Type 2 diabetes: New associations identified between genes and metabolic markers:






In two comprehensive studies, scientists from Helmholtz Zentrum Muenchen, Ludwig-Maximilians-Universitaet Muenchen and Technische Universitaet Muenchen discovered new associations of two major Type 2 diabetes risk genotypes and altered plasma concentrations of metabolic products. The “Virtual Institute Diabetes” joint research cooperation is thereby making an important contribution towards explaining the genetic and molecular basis of diabetes, The results have been published in the journals PLOS ONE and Metabolomics.

For these investigations, participants of the population-based cohort study KORA* carrying high-risk diabetes gene variants without having a diagnosed diabetes, as well as participants without an increased diabetes risk were recruited.

All study participants were subjected to a metabolic load. The nutritients, particularly sugars and fats, were administered either orally or intravenously. The scientists subsequently determined the concentrations of 163 metabolic products in blood samples from the participants. The teams headed by Prof. Dr. Thomas Illig (HMGU) and Dr. Harald Grallert (HMGU), Prof. Dr. Jochen Seißler (LMU), and Prof. Dr. Hans Hauner (TUM) and Dr. Helmut Laumen (TUM) were the first to supply a comprehensive characterisation of the metabolic performance in regard to the respective genotype.

It was observed that the concentrations of the recorded substances represent a particular metabolomic response pattern depending on the genotype. It was possible to verify specific metabolic effects, particularly for the TCF7L2 genotype, which is associated with an increased risk of type 2 diabetes. “We are aware of certain high-risk gene variants for type 2 diabetes. However, the causative mechanisms on the path to this disease are still largely unknown. With our results, we are helping to close the gap between disease-associated genes on the one hand and the development of diabetes on the other. A typically changed metabolic performance can supply early indications of diabetes”, explain Simone Wahl from HMGU and Cornelia Then from LMU, first authors of the two publications.

The scientists are currently investigating metabolic responses in additional genotypes. The objective is to advance the fundamental research on the widespread disease diabetes and to contribute the acquired knowledge to the clinical cooperation groups that have developed from the VID in order to promote the knowledge transfer between the laboratory and clinical care of patients suffering from diabetes.