Every week there are numerous scientific studies published. Here’s a look at some of the more interesting ones.
Every week there are numerous scientific studies published. Here’s a look at some of the more interesting ones.
COVID-19 Infection Doesn’t Seem to Confer Strong Antibody Response
A new study out of Northwestern University published in Scientific Reports shows that previous exposure to SARS-CoV-2, the virus that causes COVID-19, doesn’t guarantee a high antibody response. It also suggests that a robust antibody response isn’t guaranteed after a single dose of the vaccine. The data supports full vaccination, even for people who caught COVID-19. The researchers tested blood samples from adults who tested positive for COVID-19 to evaluate how long the immunity benefits of the Pfizer-BioNTech and Moderna mRNA vaccines lasted and how well they protect against variants. The participants submitted blood samples two to three weeks after their first and second vaccine doses and two months after the second dose.
“When we tested blood samples from participants collected about three weeks after their second vaccine dose, the average level of inhibition was 98%, indicating a very high level of neutralizing antibodies,” said Thomas McDade, a Northwestern biological anthropologist who worked with pharmacologist Alexis Demonbreun, on the study.
They also tested emerging variants, including Alpha (UK), Beta (South Africa), and Gamma (Brazil). They found the inhibition levels to the variants were significantly lower, ranging from 67% to 92%. Testing samples two months after the second dose, the investigators found antibody responses dropped by approximately 20%. The people with clinically confirmed COVID-19 and multiple symptoms had a higher response level than people who tested positive but had mild symptoms or were asymptomatic.
“Our study shows that prior exposure to SARSo-CoV-2 does not guarantee a high level of antibodies, nor does it guarantee a robust antibody response to the first vaccine dose,” McDade said. “For people who had mild or asymptomatic infections, their antibody response to vaccination is essentially the same as it is for people who have not been previously exposed.”
Asymptomatic COVID-19 May Still Cause Damage
A research study published in the Annals of Internal Medicine by Eric Topol and Daniel Oran from Scripps Research Translational Institute suggests that even asymptomatic COVID-19 infections may cause lung damage. The research began by evaluating data from patients aboard the cruise ship Diamond Princess which was quarantined off the coast of Japan in the earliest part of the pandemic. Of the 104 patients who tested positive on the ship, 76 were asymptomatic. However, CT scans found 54% had lung abnormalities known as ground glass opacities, which are indicative of fluid build-up in the lungs. It also included data from other parts of the world.
Predicting Alzheimer’s Through a New Brain Model
A study from investigators with Brigham and Women’s Hospital has the potential to predict Alzheimer’s progress. They created an induced pluripotent stem cell (iPSC) line from more than 50 different people that also had longitudinal clinical data, quantitative neuropathology data, and genetic and molecular brain tissue profiling. They turned the stem cells into brain cells and analyzed the molecular pathways of the living neurons in a Petri dish. They identified specific types of beta-amyloid and tau, both abnormal proteins associated with cognitive decline and Alzheimer’s, as well as signaling pathways that affected the production of the proteins. The people’s different genetic backgrounds created different profiles of beta-amyloid and tau, which are predictive in nature. Of interest as well is the possibility that antibody drugs against these proteins, such as Biogen’s aducanumab, may respond differently to different species of the proteins, the test may be used to determine what patients the drugs would be effective for.
Using Electrical Stimulation to Speed Tendon Healing
Researchers with the National University of Ireland Galway developed a device that assists tendon cell function and repair via electrical stimulation from an implantable device. In addition, the device is powered by body movement. The device uses a fabric-like mesh called piezoelectric material that generates electricity when stretched or placed under mechanical pressure. They can be tailored to individual patients or disorders.
“Our discovery shows that an electrical charge is produced in the treatment target area — the damaged or injured tendon — when the implanted device is stretched during walking. The potential gamechanger here is like a power switch in a cell — the electrical stimulus turns on tendon-specific regenerative processes in the damaged tendon,” said Marc Fernandez, who carried out the principal research study at CURAM, the SFI Research Centre for Medical Devices based at NUI Galway.
Identifying Proteins That Drive Glioblastoma
Investigators at McGill University identified proteins that drive cancer stem cells, specifically galectin1. Glioblastoma is the most common and aggressive brain tumor in adults and is typically resistant to treatment. Surgery, radiation, and chemotherapy can ease symptoms for a few months, but the cancer cells usually regrow after treatment. The researchers found that by inhibiting the galectin1 protein, the brain tumors didn’t grow for several months. Galectin1 interacts with another protein, HOXA5, to control the pathways that drive cancer stem cell behavior. Suppressing galectin1 in preclinical models significantly improved tumor responses to radiation therapy and extended the lifespan of the animals they were working with.
MMR and Tdap Vaccines Might Protect Against Severe COVID-19
A study out of Brigham and Women’s Hospital suggests that the childhood vaccines for Measles-Mumps-Rubella (MMR) and Tetanus-Diphtheria-Pertussis (Tdap) may prevent severe COVID-19. They theorize these vaccines might generate cross-reactive memory T cells that respond to antigens to a few microorganisms, including the viral antigens in SARS-CoV-2. They analyzed T cell responses to antigens from the blood of COVID-19 convalescent patients as well as patient vaccinated against COVID-19 and compared them to antigens from SARS-CoV-2 and the MMR and Tdap vaccines. Working with Cleveland Clinic, they pulled data from a cohort of COVID-19 patients that found previous MMR or Tdap vaccinated was linked to decreased disease severity. Patients previously vaccinated for MMR had a 38% decrease in hospitalization and a 32% decrease in ICU admission and death. Patients who received the Tdap had 23% and 20%, respectively, for hospitalization and ICU admission and death.
“Our Cleveland Clinic colleagues observed an association where individuals with COVID-19 who had either MMR or Tdap vaccines had a much lower frequency of going to the intensive care unit or dying,” said co-author Andrew Lichtman, immunology and senior investigator in the Brigham and Women’s Hospital Department of Pathology and Professor of Pathology at Harvard Medical School. “Although previous smaller studies suggested a similar link, our in-depth epidemiological analyses, together with our basic research results, suggest that these commonly given vaccines may protect against severe disease.”
