Smart Contact Lenses for Cancer Diagnostics and Screening

Scientists from the Terasaki Institute for Biomedical Innovation (TIBI) have developed a contact lens that can capture and detect exosomes, nanometer-sized vesicles found in bodily secretions which have the potential for being diagnostic cancer biomarkers. The lens was designed with microchambers bound to antibodies that can capture exosomes found in tears. This antibody- conjugated signaling microchamber contact lens (ABSM-CL) can be stained for detection with nanoparticle-tagged specific antibodies for selective visualization. This offers a potential platform for cancer pre-screening and a supportive diagnostic tool that is easy, rapid, sensitive, cost-effective, and non-invasive.

Exosomes are formed within most cells and secreted into many bodily fluids, such as plasma, saliva, urine, and tears. Once thought to be the dumping grounds for unwanted materials from their cells of origin, it is now known that exosomes can transport different biomolecules between cells. It has also been shown that there is a wealth of surface proteins on exosomes – some that are common to all exosomes and others that are increased in response to cancer, viral infections, or injury. In addition, exosomes derived from tumors can strongly influence tumor regulation, progression, and metastasis.

Because of these capabilities, there has been much interest in using exosomes for cancer diagnosis and prognosis/treatment prediction. However, this has been hampered by the difficulty in isolating exosomes in sufficient quantity and purity for this purpose. Current methods involve tedious and time-consuming ultracentrifuge and density gradients, lasting at least ten hours to complete.

Source: https://terasaki.org/

Low-cost Test Detects Delta Variant in Saliva

The most accurate COVID-19 tests require laboratory equipment and technical skills to determine results. This limits the speed of COVID-19 test, track and trace systems, making it more difficult to slow the spread of the disease. Laboratories also have to genetically sequence samples to test for specific variants, which takes even more time and resources. While at-home tests exist, many require self-collection and mailing to a central laboratory. Others are similar to rapid antigen tests, which have a high potential for false-negative and false-positive results. Moreover, these tests do not detect different variants of COVID-19.

Variants of the SARS-CoV-2 virus may have different transmission rates, require different treatments, and respond differently to vaccines. Scientists from Harvard University and the Massachusetts Institute of Technology (MIT), both in Cambridge, MA, and several Boston-area hospitals, recently created miSHERLOCK, an inexpensive, CRISPR-based diagnostic test that allows users to self-test for variants of SARS-CoV-2 at home, using their saliva.

Simple things that used to be ubiquitous in the hospital, like nasopharyngeal swabs, were suddenly hard to get, so routine sample processing procedures were disrupted, which is a big problem in a pandemic setting,” said co-first author of the study, Dr. Rose Lee, who is a visiting fellow at the Wyss Institute for Biologically Inspired Engineering at MIT.

Our team’s motivation for this project was to eliminate these bottlenecks and provide accurate diagnostics for COVID-19 with less reliance on global supply chains, and could also accurately detect the variants that were starting to emerge,” she notes.

miSHERLOCK is a low-cost point-of-care [COVID-19] test that is capable of detecting and differentiating specific SARS-CoV-2 variants, which could be used to guide patient care as well as for infection control or epidemiological purposes,” lead author Helena de Puig Guixe, a postdoctoral researcher at the Collins lab at the Wyss Institute for Biologically Inspired Engineering, told Medical News Today.

Our device is low-cost, provides a simple visual answer in 1 hour, and only requires saliva from a patient with no additional equipment separate from the device itself (including its standard battery). […] Our full device, including all testing components, costs $15, down to $6 with reuse of the housing and electronics, but could be as low as $2–3 per test if produced at scale,” she added.

Source: https://www.medicalnewstoday.com/

A Single Drop of Blood Can Reveal Stress Hormones

A Rutgers-led team of researchers has developed a microchip that can measure stress hormones in real time from a drop of blood.

Cortisol and other stress hormones regulate many aspects of our physical and mental health, including sleep quality. High levels of cortisol can result in poor sleep, which increases stress that can contribute to panic attacks, heart attacks and other ailments.

Currently, measuring cortisol takes costly and cumbersome laboratory setups, so the Rutgers-led team looked for a way to monitor its natural fluctuations in daily life and provide patients with feedback that allows them to receive the right treatment at the right time.

The researchers used the same technologies used to fabricate computer chips to build sensors thinner than a human hair that can detect biomolecules at low levels. They validated the miniaturized device’s performance on 65 blood samples from patients with rheumatoid arthritis.

The use of nanosensors allowed us to detect cortisol molecules directly without the need for any other molecules or particles to act as labels,” said lead author Reza Mahmoodi, a postdoctoral scholar in the Department of Electrical and Computer Engineering at Rutgers University-New Brunswick.

With technologies like the team’s new microchip, patients can monitor their hormone levels and better manage chronic inflammation, stress and other conditions at a lower cost, said senior author Mehdi Javanmard, an associate professor in RutgersDepartment of Electrical and Computer Engineering.

Our new sensor produces an accurate and reliable response that allows a continuous readout of cortisol levels for real-time analysis,” he added. “It has great potential to be adapted to non-invasive cortisol measurement in other fluids such as saliva and urine. The fact that molecular labels are not required eliminates the need for large bulky instruments like optical microscopes and plate readers, making the readout instrumentation something you can measure ultimately in a small pocket-sized box or even fit onto a wristband one day.”

The study included Rutgers co-author Pengfei Xie, a Ph.D. student, and researchers from the University of Minnesota and University of Pennsylvania. The research was funded by the DARPA ElectRX program.

The study appears in the journal Science Advances.

Source: https://www.rutgers.edu/

Speak Is Sufficient To Spread Coronavirus

Tiny droplets of saliva that are sprayed into the air when people speak may be sufficient to spread coronavirus, according to US government scientists who say the finding could help control the outbreak. Researchers at the US National Institutes of Health (NIH) in Maryland found that talking released thousands of fine droplets into the air that could pose a risk to others if the speaker were infected with the virus.

The scientists used laser imaging and high-speed videography to show how thousands of droplets that are too small to see with the naked eye are emitted in normal speech, even in short phrases such as “stay healthy”. The work is preliminary and has not been peer-reviewed or published, but in a report the scientists claim the findings may have “vital implications” for containing the pandemic.

If speaking and oral fluid viral load proves to be a major mechanism of Sars-CoV-2 [the official name of the virus] transmission, wearing any kind of cloth mouth cover in public by every person, as well as strict adherence to social distancing and handwashing, could significantly decrease the transmission rate and thereby contain the pandemic until a vaccine becomes available,” the researchers write.

The results will fuel the ongoing debate over whether or not healthy people should wear face masks in public. Recent advice from the US Centers for Disease Control and Prevention called for members of the public to wear cloth face covers when they visit places where it is hard to maintain physical distancing, such as pharmacies and grocery stores.

But the US advice contrasts with that from the World Health Organization, which reviewed its stance on face masks last week. In updated guidance published on Monday it restated that there was no evidence wearing a mask in public prevented people from picking up respiratory infections such as Covid-19.

Source: https://www.theguardian.com/