Blood test

Scientists in Israel are working on developing a blood test that can detect pancreatic and colorectal cancer. Although still in the testing phase, the method is reported to be 92% accurate, and could ultimately be adapted to detect other types of cancer and even other diseases.

This is the promise of a team of researchers at the Weizmann Institute of Science, with their findings published in the journal “Nature Biotechnology”.

Once the sample is collected, the researchers subject it to a single-molecule imaging process developed by Dr Efrat Shema, the project’s lead researcher, which allows for epigenetic mapping using a fluorescent microscope.

The researchers are then able to visualise epigenetic markings on nucleosomes, which are pieces of DNA wrapped around protein “spools”. According to Shema, the millions of nucleosomes in the blood can be analysed to detect cancer.

To conduct their research, the specialists compared these DNA extracts from 30 healthy people with those from a group of 60 patients with different stages of colorectal cancer. They then combined their results with artificial-intelligence algorithms.

“Our algorithm could tell the difference between the healthy and the patient groups at a record level of certainty for studies of this type,with 92% precision,” Shema said.

The findings could simplify screening for colorectal cancer – which is currently detectable by colonoscopy, an invasive test that can be daunting for patients – as well as for pancreatic cancer, for which no diagnostic test exists.

While this method has yet to be validated through clinical trials, the specialists hope this approach will one day make it possible to diagnose various forms of cancer, as well as other conditions that leave markers in the blood such as cardiac or autoimmune diseases.

Researchers from the University of Geneva (UNIGE) in Switzerland are looking into developing a blood test for early detection of diabetes for patients at risk. The test would check for a molecular biomarker that could be associated with a deterioration in pancreatic beta cells – impairment of insulin secretion from these pancreatic cells are what gives rise to diabetes.

Patients whose blood sugar levels are elevated but below the official threshold for type 2 diabetes are diagnosed with a condition called prediabetes. Fortunately, nearly half patients with proper management of prediabetes will most likely not go on to develop type 2 diabetes.

Still, identifying the disease onset before it claims crucial pancreatic cells – in addition to monitoring beta cell activity – would be beneficial to both doctors and patients.

“Identifying the transition from pre-diabetes to diabetes is complex, because the status of the affected cells, which are scattered in very small quantities in the core of an organ located under the liver, the pancreas, is impossible to assess quantitatively by non-invasive investigations,” explained Professor Pierre Maechler, from the UNIGE Faculty of Medicine.

“We therefore opted for an alternative strategy: to find a molecule whose levels in the blood would be associated with the functional mass of these beta cells in order to indirectly detect their alteration at the pre-diabetes stage, before the appearance of any symptoms.”

Professor Maechler scanned thousands of different molecular biomarkers in a variety of mouse models of diabetes and homed in on one specific sugar called 1,5-anhydroglucitol. Low levels of 1,5-anhydroglucitol could be associated with deficits in pancreatic beta cells.

More interestingly, levels of 1,5-anhydroglucitol was indicative of the functional quantity of pancreatic beta cells. The researchers confirmed the link between 1,5-anhydroglucitol and beta cells by studying changes in the blood levels of non-diseased patients who underwent surgery to remove parts of the pancreas.

Professor Maechler and colleagues is plan to study 1,5-anhydroglucitol in patients at different stages of disease to inform a potential blood test for measuring diabetes risk.

Scientists from the University of Oxford, UK, have developed a cheap and simple blood test that can detect the presence of a wide range of cancer types as well as provide an estimate on whether it has metastasised (spread) throughout the patient’s body.

Blood tests for cancer typically look for genetic material from tumorous cells – the new metabolomic blood analysis test, however, relies on a technique called NMR metabolomics which involves the use of magnetic fields and radio waves to measure metabolite levels in the patient’s blood; raw data from the test is then run through an algorithm that distinguishes between these states and offers a diagnosis.

It is the first method to be developed that can determine metastatic cancer from a blood test without previous knowledge of the type of cancer the patient is suffering from.

“Cancer cells have unique metabolomic fingerprints due to their different metabolic processes. We are only now starting to understand how metabolites produced by tumours can be used as biomarkers to accurately detect cancer,” said Dr. James Larkin from the University of Oxford.

The study worked with samples harvested from 300 patients recruited through the Oxfordshire Suspected CANcer (SCAN) Diagnostic Pathway. All participants reported non-specific cancer symptoms, including fatigue and weight loss. The scientists explained that patients with localised cancer, those with metastatic cancer, and healthy individuals all have different metabolite profiles in their blood, and sought to assess whether their test could tell them apart.

Ultimately, the test correctly detected the disease in 19 out of every 20 patients with cancer and identified the metastatic phase of the disease with an overall accuracy of 94%.

Early detection of cancer improves a patient’s chances of a successful outcome, the scientists note. Being rapid and cheap to administer, this test could help improve the overall rate of successful cancer treatments, especially in patients who only show non-specific symptoms (for whom a diagnosis takes longer).

“We envisage that metabolomic analysis of the blood will allow accurate, timely and cost-effective triaging of patients with suspected cancer, and could allow better prioritisation of patients based on the additional early information this test provides on their disease,” said Dr. Fay Probert, also from the University of Oxford.

Read: Scientists develop blood test to measure body’s circadian rhythm

The human body’s internal clock, or circadian rhythm influences all matters related to health and well-being, including the optimal time to exercise or take medication; but measuring a person’s individual circadian rhythm has so far been, unfortunately, tedious. However, scientists at the University of Colorado (CU) Boulder, US, have found a way to determine an individual’s circadian rhythm by analysing a series of molecules just with a simple blood test.

According to then Assistant professor of Integrative Physiology at CU Boulder, Christopher Depner, the discovery “is an important step forward in paving the way for circadian medicine, for personalised medicine,” where treatments and wellness regimes are better tailored to individuals.

Related: Enhanced blood test monitoring with new lab-on-chip technology

Researchers have long known that a central “master clock” in a region of the brain called the hypothalamus helps to regulate the body’s 24-hour cycle; nearly every tissue or organ in the body is synced with that master clock as well – it affects everything from hormone secretion to fat metabolism to organ function. The differing circadian rhythm between individuals is also why some people are night owls and others are early risers, or why others enjoy an afternoon nap on the couch.

Needless to say, disruption to this circadian rhythm can increase the risk of disease.

“If we can understand each individual person’s circadian clock, we can potentially prescribe the optimal time of day for them to be eating or exercising or taking medication,” said Depner.

Instead of the dim-light melatonin assessment – the gold standard for measuring the body’s internal clock – scientists at CU Boulder chose to take a different approach referred to as “metabolomics.” Here, the scientists enlisted 16 volunteers who spent 14 days in a sleep lab and provided hourly blood tests for analysis. They simultaneously assessed the levels of 4,000 different metabolites in their blood, including amino acids, vitamins and fatty acids, associated with each individual’s circadian clock using a machine learning algorithm – this “molecular fingerprint” could accurately predict the circadian phase from a single sample.

While the technique currently needs to look at some 65 metabolites, the scientists say it should be narrowed down further to make it commercially viable. Further, there are other problems to solve before the technology moves beyond the lab, such as the fact it was far more accurate when the subjects were well rested and hadn’t eaten recently.

But the study is a critical first step, said the Director of the Sleep and Chronobiology Lab at CU Boulder. Other research, including some from Wright’s lab, is exploring proteomics (looking for proteins in blood) or transcriptomics (measuring the presence of ribonucleic acid or RNA) to assess circadian rhythm(s).

Scientists at New Orleans’ Tulane University, US, have devised a blood test that checks for tuberculosis (TB) in young children – the test is claimed to detect the presence of mycobacterium tuberculosis microbesup to a year before the disease itself occurs.

It can be difficult to detect tuberculosis in young children: they may not exhibit typical symptoms initially, or may have trouble producing the sputum samples needed to check for TB-causing bacteria in their respiratory system; and because the amount of bacteria in a child’s sample is often much smaller than the amount in a sample provided by an adult, standard testing may prove to be inaccurate.

The new blood test checks for a protein known as CFP-10 secreted by TB-causing bacteria, and may be present in the bloodstream up to 60 weeks before the child actually develops the disease. Only a small blood sample is needed, as an antibody is added to enrich any CFP-10 that may be present, causing it to better show up when analysed by a mass spectrometer

The blood test was found to deliver 100% accurate results when testing stored blood samples that had previously been obtained from a total of 519 children – it identified the individuals who had been diagnosed with tuberculosis via “gold-standard” testing techniques. Additionally, it also identified 83.7% of the children who those traditional tests missed, but who were later diagnosed with tuberculosis by their physicians.

“This is a breakthrough for infants with tuberculosis because we don’t have this kind of screening technology to catch early infections among those youngest groups who are most likely to be undiagnosed,” said Dr. Tony Hu, Presidential Chair in Biotechnology Innovation at Tulane University. “I hope this method can be pushed forward quickly to reach these children as early as possible.”

The scientists are now developing an inexpensive portable device that could perform the blood tests onsite, in settings such as impoverished communities where lab testing may not be available.

Read: Antibodies may offer protection against tuberculosis

A new blood test is able to check if those with mild memory loss are at risk of developing Alzheimer’s disease (AD) later on.  AD is notoriously difficult to diagnose until much too late, so scientists at Sweden’s Lund University looked at ways to pick up the disease during its early stages, before it develops into dementia.

Their search focused on two proteins in the blood called phosphorylated tau and neurofilamet light, which have both featured as part of AD blood testing technologies. Analysing the levels of these two proteins in the blood of 573 subjects with memory loss helped the scientists build a revolutionary online tool; it incorporates data like age, gender and results from cognitive tests and combines them with results from the blood test to predict more accurately the risk of developing AD within two years or four years.

“Many people with AD seek care when they have only developed mild memory impairment, meaning many years before the dementia stage of the disease,” said the university’s professor of neurology Oskar Hansson, who led the research.

Read: New blood test for early-stage Alzheimer’s disease detection 100% accurate

“It is often difficult for doctors to give the correct diagnosis in people with mild memory impairment, as many different conditions other than AD can be the cause – our goal […] has been to find simple methods that can be used in primary care to make an early diagnosis and to begin treatment to relieve symptoms at an earlier stage.” While promising, the tool is currently only intended for use in research.

An early-stage cancer detection blood test, designed to detect at least 50 types of cancer, will be trialled by the NHS in England for the next three years. Developed by US biotechnology company Grail, the test can detect molecular changes in the blood caused by cancer in people with no obvious symptoms – some 165,000 people with possible symptoms will be asked to take the tests as part of a pilot funded by Grail.

Developing an accurate and reliable blood test for cancer has been a difficult effort because the test sometimes doesn’t detect a person’s cancer when they do have it, or it indicates someone has cancer when they don’t. It is also crucial to detect cancer at an earlier stage to give patients a better chance at successful treatment and survival.

The NHS hopes the blood tests will help increase five-year survival rates for cancer patients in the UK, which are below the levels seen in many other high-income countries.

“This promising blood test could therefore be a game-changer in cancer care, helping thousands more people to get successful treatment,”said Sir Simon Stevens, NHS England Chief executive.

Similarly, Cancer Research UK said large research studies of tests for treatments were “essential to determine if they’re effective, and a vital step in getting them to patients, if proven to work.”

The pilot has also drawn some skepticism – others in the medical community have cautioned that the blood test was yet untried and untested in a large-scale medical trial.

Read: New blood test can check for at least 50 types of cancer before symptoms of disease

The findings are the latest effort to develop a blood test for autism spectrum disorder, which is estimated to affect about 1 in 68 babies. The cause remains a mystery although it has been shown that childhood vaccines are not responsible.

The hope for such tests, if proven accurate, is that they could reassure parents with autism fears as well as possibly aid in the development of treatments, co-author to the study, Dr.  Juergen Hahn of Rensselaer Polytechnic Institute in New York, US.

They could also speed the age at diagnosis. Autism encompasses a wide spectrum of disorders, ranging from profound inability to communicate and mental retardation to relatively mild symptoms, as in Asperger’s Syndrome.

Doctors typically diagnose children by observing behaviors associated with the disorder, such as repetitive behaviors or social avoidance. Most children are not diagnosed until around age 4, although some skilled clinicians can pick it up earlier.

Hahn and colleagues measured levels of 24 proteins that have been linked to autism and found five that, in the right combination, seemed most predictive of the condition, which affects about 1.5% of children and can vary widely in severity and how it manifests.

The researchers derived the combination by testing 83 children aged 3 to 10 who had been diagnosed with autism through conventional means. While the combination was present in 97.6%, it was absent in 96.1% of 76 normal children.

Dr. Max Wiznitzer of the University Hospitals Cleveland Medical Center, who was not involved in the research, called the finding “interesting, but not earth-shattering,” saying that it needs to be tested by many more at-risk children.

He said it is still unknown if the marker is specific to autism or whether it’s a marker for any chronic illness of any kind. He also noted that the research offers no evidence that the chemical combination being blamed for autism “will be there for infants and toddlers.”

Wiznitzer said the researchers still quite a way to go before they can show it has any meaning.