The apolipoprotein E gene ε4 allele is considered a negative factor for neural regeneration in late-onset Alzheimer’s disease cases. Apolipoprotein E genotyping is crucial to apolipoprotein E polymorphism analysis. Peripheral venous blood is the conventional tissue source for apolipoprotein E genotyping polymorphism analysis. Blood yields high-quality genomic DNA and can meet various research purposes. However, because of invasiveness, taking blood samples decreases compliance among the elderly, especially neuropsychiatric patients. Moreover, blood specimens often need cold storage, thereby increasing the cost. A research team from Department of Neurology, Peking University Shenzhen Hospital in China pointed out a non-invasive and fast method to genotype large samples to help to elucidate the role of apolipoprotein E gene ε4 allele in neural regeneration in the cases with late-onset Alzheimer’s disease. Genomic DNA from mouth swab specimens was extracted using magnetic nanoparticles, and genotyping was performed by real-time PCR using TaqMan-BHQ probes. Genotyping accuracy was validated by DNA sequencing. The method developed for apolipoprotein E genotyping is accurate and reliable, and also suitable for genotyping large samples, which may help determine the role of the apolipoprotein E ε4 allele in neural regeneration in late-onset Alzheimer’s disease cases.

The absence of a protein called SMG1 could be a contributing factor in the development of Parkinson’s disease and other related neurological disorders, according to a study led by the Translational Genomics Research Institute (TGen).

The study screened 711 human kinases (key regulators of cellular functions) and 206 phosphatases (key regulators of metabolic processes) to determine which might have the greatest relationship to the aggregation of a protein known as alpha-synuclein, which has been previously implicated in Parkinson’s disease. Previous studies have shown that hyperphosphorylation of the α-synuclein protein on serine 129 is related to this aggregation.

‘Identifying the kinases and phosphates that regulate this critical phosphorylation event may ultimately prove beneficial in the development of new drugs that could prevent synuclein dysfunction and toxicity in Parkinson’s disease and other synucleinopathies,’ said Dr. Travis Dunckley, a TGen Assistant Professor and senior author of the study.

Synucleinopathies are neurodegenerative disorders characterised
by aggregates of α-synuclein protein. They include Parkinson’s, various forms of dementia and multiple systems atrophy (MSA).

By using the latest in genomic technologies, Dr. Dunckley and collaborators found that expression of the protein SMG1 was ‘significantly reduced’ in tissue samples of patients with Parkinson’s and dementia.

‘These results suggest that reduced SMG1 expression may be a contributor to α-synuclein pathology in these diseases,’ Dr. Dunckley said.

TGen collaborators in this study included researchers from Banner Sun Health Institute and Mayo Clinic Scottsdale. Translational Genomics Research Institute

Studying epithelial cells, the cell type that most commonly turns cancerous, Johns Hopkins researchers have identified a protein that causes cells to release from their neighbours and migrate away from healthy mammary, or breast, tissue in mice. They also found that deletion of a cellular ‘Velcro protein’ does not cause the single-celled migration expected. Their results, they say, help clarify the molecular changes required for cancer cells to metastasize.

Because epithelial cells give rise to 85 percent of all cancers, the work may have implications outside of breast cancer.

Epithelial cells line the inside and outside of organs throughout the body. The team focused their work on mammary epithelial cells, which form the ducts that carry milk within the breast. ‘Tumour cells have to break their connections to other epithelial cells in order to leave the breast and build metastases in other parts of the body,’ explains Andrew Ewald, Ph.D., assistant professor of cell biology and oncology at the Johns Hopkins University School of Medicine.

For their study, Ewald’s team removed small pieces of mammary tissue from normal mice and grew them in gels that mimic their natural environment. By using coloured proteins to mark different types of cells, they were able to use microscopes to watch how cell behaviour varied with the genetics of the cells.

The first protein they studied was E-cadherin, which is found on the surface of most epithelial cells and is used to connect epithelial cells to each other. E-cadherin is like the Velcro that holds epithelial cells together, and its absence is often associated with human breast cancers, says Ewald.

In one experiment, the team deleted the protein from normal mouse mammary cells and watched what happened. Expecting the cells to completely disconnect and move out on their own into the surrounding gel, the researchers were surprised to find that most of the epithelial cells remained connected to each other, although their organisation was disrupted. Some of the epithelial cells did penetrate the gel, but usually in single-file ‘columns’ that remained connected to the tissue. A similar result was seen in live mice.

‘For tumour cells to metastasise, they have to begin interacting with the proteins outside of the tumour and eventually strike out on their own,’ says Eliah Shamir, a graduate student in Ewald’s lab and lead author on the study. ‘When we deleted E-cadherin, the epithelial cells began interacting more with proteins in the gel, but they didn’t lose contact with the rest of the mammary tissue.’

In a second set of experiments, the team turned on a gene called Twist1, which is thought to affect the activity of many genes needed to transform groups of stationary epithelial cells into independent, mobile cells. The result, they say, was dramatic. Within 24 hours of turning on Twist1, dozens of individual cells began to move past the epithelial boundary and into the gel beyond. Again, similar results were seen when the experiment was repeated in live mice.

Surprisingly, the researchers say that when they caused epithelial cells lacking E-cadherin to turn on Twist1, the cells were no longer able to escape into the gel as single cells. Instead, they created many ‘columns’ of cells, which didn’t detach from the mammary tissue. These results suggest that the single-celled detachment and migration induced by Twist1 actually requires the presence of E-cadherin — the Velcro protein that helps bind the cells together. ‘This finding is quite counterintuitive,’ Ewald says, ‘and we are eager to understand the biology behind it.’

Since Twist1 is known to affect the activity of many genes, the researchers have begun to narrow down which of those genes is responsible for the cellular spread they witnessed. With that information, they hope to identify new means of preventing metastasis.

‘Our goal is to improve outcomes for patients with metastatic breast cancer, and this work takes us one step closer to doing so,’ says Ewald. John Hopkin’s Medicine

Newly developed test can identify sickle cell disease in minutes and could be used in rural clinics around the globe
Within minutes after birth, every child in the U.S. undergoes a battery of tests designed to diagnose a host of conditions, including sickle cell disease. Thousands of children born in the developing world, however, aren’t so lucky, meaning many suffer and die from the disease each year.

A.J. Kumar hopes to put a halt to at least some of those deaths.

A Post-Doctoral Fellow in Chemistry and Chemical Biology working in the lab of George Whitesides, the Woodford L. and Ann A. Flowers University Professor, Kumar and colleagues, including other co-authors, have developed a new test for sickle cell disease that provides results in just 12 minutes and costs as little as 50 cents – far faster and cheaper than other tests.

‘The tests we have today work great, they have a very high sensitivity,’ Kumar said. ‘But the equipment needed to run them costs in the tens of thousands of dollars, and they take hours to run. That’s not amenable to rural clinics, or even some cities where the medical infrastructure isn’t up to the standards we see in the U.S. That’s where having a rapid, low-cost test becomes important and this paper shows such a test can potentially work.’

When run against more than 50 clinical samples – 26 positive and 26 negative – the new test showed good sensitivity and specificity for the disease, Kumar said, so the early evidence is promising, but additional testing will be needed to determine whether the test is truly accurate enough to use in the field.

The test designed by Kumar is deceptively simple, and works by connecting two ideas scientists have understood for decades.

The first is the notion that blood cells affected by the disease are denser than normal cells, and the second is that many polymers, when mixed in water, automatically separate into layers ordered by density.

Conventional methods to separate cells by density relied on layering liquids with different density by hand. The insight, arrived at by Charles Mace (now at Tufts) and Kumar, was that the self-forming layers could be used to separate cells, such as red blood cells, by density.

‘When you mix the polymers with water, they separate just like oil and water,’ he said. ‘Even if you mix it up, it will still come back to those layers.’

It wasn’t until a chance meeting with Dr. Thomas Stossel, however, that Kumar believed the technology might have a real impact on sickle cell disease.

‘Initially, we started off working on malaria, because we thought when parasites invaded the cells, it would change their density,’ he said. ‘But when I met Tom Stossel on a panel at the Harvard Medical School, he said, ‘You need to work on sickle cell.’ He’s a haematologist by training and has been working with a non-profit in Zambia for the past decade, so he’s seen the need and the lack of a diagnostic tool.’

When Kumar and colleagues ran tests with infected blood, their results were unmistakable. While healthy red blood cells settled in the tubes at specific levels, the dense cells from blood infected with sickle cell settled in a band significantly lower. The band of red cells could clearly be seen by eye.

Just showing that the test worked, however, wasn’t enough.

‘We wanted to make the test as simple as possible,’ Kumar explained. ‘The idea was to make it something you could run from just a finger prick. Because these gradients assemble on their own, that meant we could make them in whatever volume we wanted, even a small capillary tube.’

The design the team eventually settled on is barely larger than a toothpick. In the field, Kumar said, running the test is as simple as uncapping the tube, pricking a patient’s finger and allowing the blood to wick into the tube.

While further study is needed to determine how accurate and effective the test may be, Kumar said stopping even a few sickle-cell-related deaths would EurekAlert

Using new stem cell technology, scientists at the Salk Institute have shown that neurons generated from the skin cells of people with schizophrenia behave strangely in early developmental stages, providing a hint as to ways to detect and potentially treat the disease early.
The findings of the study support the theory that the neurological dysfunction that eventually causes schizophrenia may begin in the brains of babies still in the womb.
‘This study aims to investigate the earliest detectable changes in the brain that lead to schizophrenia,’ says Fred H. Gage, Salk professor of genetics. ‘We were surprised at how early in the developmental process that defects in neural function could be detected.’
Currently, over 1.1 percent of the world’s population has schizophrenia, with an estimated three million cases in the United States alone. The economic cost is high: in 2002, Americans spent nearly $63 billion on treatment and managing disability. The emotional cost is higher still: 10 percent of those with schizophrenia are driven to commit suicide by the burden of coping with the disease.
Although schizophrenia is a devastating disease, scientists still know very little about its underlying causes, and it is still unknown which cells in the brain are affected and how. Previously, scientists had only been able to study schizophrenia by examining the brains of patients after death, but age, stress, medication or drug abuse had often altered or damaged the brains of these patients, making it difficult to pinpoint the disease’s origins.
The Salk scientists were able to avoid this hurdle by using stem cell technologies. They took skin cells from patients, coaxed the cells to revert back to an earlier stem cell form and then prompted them to grow into very early-stage neurons (dubbed neural progenitor cells or NPCs). These NPCs are similar to the cells in the brain of a developing fetus.
The researchers generated NPCs from the skin cells of four patients with schizophrenia and six people without the disease. They tested the cells in two types of assays: in one test, they looked at how far the cells moved and interacted with particular surfaces; in the other test, they looked at stress in the cells by imaging mitochondria, which are tiny organelles that generate energy for the cells.
On both tests, the Salk team found that NPCs from people with schizophrenia differed in significant ways from those taken from unaffected people.
In particular, cells predisposed to schizophrenia showed unusual activity in two major classes of proteins: those involved in adhesion and connectivity, and those involved in oxidative stress. Neural cells from patients with schizophrenia tended to have aberrant migration (which may result in the poor connectivity seen later in the brain) and increased levels of oxidative stress (which can lead to cell death).
These findings are consistent with a prevailing theory that events occurring during pregnancy can contribute to schizophrenia, even though the disease doesn’t manifest until early adulthood. Past studies suggest that mothers who experience infection, malnutrition or extreme stress during pregnancy are at a higher risk of having children with schizophrenia. The reason for this is unknown, but both genetic and environmental factors likely play a role. Salk Institute for Biological Studies