Tag: 2/6/21

New Antibody Treatment for Crimean-Congo Haemorrhagic Fever

Deer tick (Ixodes scapularis). Photo by Erik Karits on Unsplash

Working with international colleagues, US Army scientists have developed and tested an antibody-based therapy to treat Crimean-Congo haemorrhagic fever virus (CCHFV). 

The deadly virus is carried by ticks and has a high mortality rate, killing up to 60% of those infected. Their findings are published in the journal Cell.

The researchers characterised the human immune response to natural CCHFV infection by using blood samples donated by disease survivors. They were able to identify several potent neutralising antibodies that target the viral glycoprotein–a viral component which has a key role in disease development. A number of of these antibodies, administered individually or in combination, successfully protected mice from CCHFV when exposed to the virus after antibody administration.

In order to treat mice that had already been infected with the virus, the team created ‘bispecific’ antibodies that combined potency with the ability to bind to two different sites on the CCHFV glycoprotein. One of these bispecific antibodies, called DVD-121-801, overcame CCHFV infection in mice with just a single dose administered 24 hours after challenge with live virus.

DVD-121-801 as a potential therapeutic for human patients, according to co-first author Andrew H. Herbert, Ph.D., of the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID).

CCHFV is the most prevalent tick-borne virus that causes human disease, and is endemic in countries across Europe, Asia, and Africa. CCHF occurs most frequently among agricultural workers following the bite of an infected tick, and to a lesser extent among slaughterhouse workers exposed to the blood and tissues of infected livestock and medical personnel through contact with the body fluids of infected patients. In spite of its high lethality and widespread distribution, there are no vaccines or specific treatments for it. It has been designated a priority pathogen by the World Health Organization.

Study co-first author Andrew H Herbert, PhD, US Army Medical Research Institute of Infectious Diseases, said: “Rodent models of CCHFV infection are useful in testing and down-selecting neutralising antibodies. However, to advance a lead candidate for therapeutic use, it will be necessary to conduct studies in larger animal models that more faithfully recapitulate human disease.”

Source: Medical Xpress

Journal information: J. Maximilian Fels et al, Protective neutralizing antibodies from human survivors of Crimean-Congo hemorrhagic fever, Cell (2021). DOI: 10.1016/j.cell.2021.05.001

Heart Risk in Transgender Men Receiving Hormones

Photo by Sharon McCutcheon on Unsplash

A study of transgender people receiving gender-affirming hormone therapy found that certain hormones increased certain cardiometabolic risk factors. 

Gender-affirming or cross-sex hormone therapy is integral to the management of transgender individuals, but there is only limited understanding of the effects of such hormones on cardiovascular health. Research is limited by the absence of large cohort studies, lack of appropriate control populations, and inadequate data acquisition from gender identity services. Existing epidemiological data suggest that the use of oestrogens in transgender females increases the risk of myocardial infarction and ischaemic stroke. Conversely, testosterone use in transgender males is currently lacking any consistent or convincing evidence of increased risk of cardiovascular or cerebrovascular disease.

This retrospective study included 129 transgender individuals receiving gender-affirming hormone therapy. In transgender males receiving testosterone, there was an average 2.5% drop in HDL cholesterol levels seen each year of using gender-affirming hormone therapy (P=0.03). However, researchers did not see this change in transgender females on estradiol during the average 48-month follow-up period. Additionally, the researchers found no significant changes in LDL cholesterol, triglycerides, HbA1c, or 25-hydroxyvitamin D levels in transgender males or transgender females.

About 53% of the participants in the study identified as transgender males, and more than 60% of the cohort was white. The median age of the total cohort was 26 with a BMI of 25.5. The majority of transgender males were on intramuscular injectable preparations of testosterone cypionate.

Similar to prior studies, a significant decrease in HDL was noted in TM on testosterone therapy. The researchers noted that further study is needed on the correlation of this finding with changes in diet and exercise while on testosterone therapy and impact on cardiovascular events. Reassuringly, no other changes noted in cardiovascular parameters.

“Further long-term data is needed for patients receiving this hormone therapy to assure that their long-term cardiovascular risk is optimised,” concluded Samihah Ahmed, MD, MBA, of Northwell Health Lenox Hill Hospital in New York City, who presented the findings.

Source: MedPage Today

Presentation information: Ahmed S, et al “Cardiometabolic risk factors in transgender individuals taking gender-affirming hormone therapy through four years” AACE 2021. 

China Reports First Human Infection of the H10N3 Avian Flu Strain

Image by Arek Socha from Pixabay

On Tuesday, China reported the world’s first human infection of the H10N3 avian flu strain but said the risk of its widespread transmission among people was low.

In the eastern city of Zhenjiang, a 41-year-old man was admitted to hospital with fever symptoms on April 28 and a month later was diagnosed with H10N3, China’s National Health Commission (NHC) said in an online statement.

The NHC said that “The risk of large-scale spread is extremely low,” and that the man was in a stable condition with his close contacts having reported no “abnormalities”.

The health body described H10N3 as being low pathogenic, ie less likely to cause death or severe illness, in birds. It said there had been no human cases of H10N3 previously reported anywhere in the world.

A number of strains of bird flu have been found among animals in China but mass outbreaks in humans are rare.

Five waves of the H7N9 influenza epidemic occurred in China between March 2013 and September 2017. Low pathogenicity H7N9 dominated in the first four waves, whereas highly pathogenic H7N9 influenza emerged in poultry and spread to humans during the fifth wave, causing widespread concern.  

H7N9 has infected 1668 people and claimed 616 lives since 2013, according to the United Nations’ Food and Agriculture Organization. In the wake of recent avian flu outbreaks in Africa and Eurasia, the head of China’s Centre for Disease Control and Prevention last week urged closer surveillance in poultry farms, markets and wild birds.

COVID was first detected at a wet market with food and live animals in the central Chinese city of Wuhan in late 2019. This is where, according to the most likely scenario from the WHO report on the virus’ origins, it is thought that the SARS-CoV-2 virus first jumped from animals to humans. 

Source: Medical Xpress

Study Reveals Natural Killer Cells’ Fuel Source

Pictured is a false-colour scanning electron micrograph of an oral squamous cancer cell (white) being attacked by two cytotoxic T cells (red), part of a natural immune response. Photo by National Cancer Institute on Unsplash

Scientists have discovered how natural killer (NK) cells fuel their activities when fighting infections, which will in turn help inform the development of immune therapies.

When it comes to dealing with infections and cancer, if T cells are like a team of specialist doctors in an emergency room, then NK cells are the paramedics: They arrive first on the scene and perform damage control until reinforcements arrive. Their existence was revealed in the 1970s when scientists were trying to characterise T cell cytotoxicity.

NK cells belong to our innate immune system, which dispatches these first responders, and they come with a built-in ability to recognise and respond to danger. Learning what powers NK cells is an ongoing area of immunology research, with important clinical implications.

“There’s a lot of interest right now in NK cells as a potential target of immunotherapy,” said Joseph Sun, an immunologist in the Sloan Kettering Institute. “The more we can understand what drives these cells, the better we can program them to fight disease.”

First responders

Previous studies have shown that aerobic glycolysis provides the energy for T cells to carry out their protective activities. But it was not known whether NK cells use this form of metabolism in performing their functions.

Dr Sun and his colleagues studied NK cells in animal models instead of in vitro, in order to find out, in a natural setting, what type of metabolism NK cells use and compare it to T cells. They discovered that NK cells increase aerobic glycolysis about five days before T cells respond with their own glycolytic surge.

“This fits with the idea that NK cells are innate immune cells that are really critical for mounting a rapid response,” said Research Fellow Sam Sheppard.

The findings are relevant to ongoing efforts to use NK cells as immunotherapy in people with cancer and other conditions. These are particularly relevant for procedures that make use of NK cells as a form of cell therapy—when cells are grown outside the body and then introduced back into the patient.

Finding a delicate balance

“If you’re growing these cells in a dish and you push them to divide too rapidly, they may not have as much potential to undergo aerobic glycolysis when you put them into a patient,” Dr Sheppard explained.

For researchers designing clinical trials, the goal is to find a balance between encouraging NK cells to multiply and preserving their stamina. These NK cells are the paramedics of our immune system, so it’s important to keep them speedy and responsive.

The findings were reported June 1, 2021, in the journal Cell Reports.

Source: Eureka Alert

Wastewater Analysis Shows KZN in Third Wave

Image source: CDC/Unsplash

Viral load analysis of wastewater suggests that KwaZulu-Natal may already have entered the third wave of COVID infections, according to research by DUT.

The Institute for Water and Wastewater Technology, based at DUT, has been monitoring viral loads of wastewater at the central treatment plant in eThekwini since July 2020, and found a clear correlation between clinical cases and viral loads detected in wastewater.

While clinical cases were reported to be on the increase in KZN since April 20 this year, they had found an increase in wastewater viral load some three weeks earlier.

The Institute for Water and Wastewater noted that the peak of the COVID second wave in South Africa occurred in January with an average of 40 000 cases in KwaZulu-Natal.

Over this period, the researchers measured average viral loads of 4.72 log copies per 100 millilitres at the central wastewater treatment plant. However, over the last four weeks, viral loads have averaged 5.57 log copies per 100 millilitres.

This has led the institute to suggest that there are far more cases than have been reported clinically, with a significant presence of asymptomatic individuals.

A report [PDF] on the third wave by the National Institute for Communicable Diseases indicated that there was a seroprevalence for SARS-CoV-2, a proxy for previous infection, of 30% to 40% after the third wave. This indicates that COVID infections were already widespread, and lends credence to the institute’s notion of extremely widespread asymptomatic cases. Projections for KZN showed a much lower peak for hospital admissions.

Source: Durban University of Technology

US Supreme Court Snubs Johnson & Johnson Talc Lawsuit Appeal

Photo by Bill Oxford on Unsplash

On Tuesday, the US Supreme Court declined to hear Johnson & Johnson’s appeal challenging a $2.12 billion ruling in favour of 20 women who developed ovarian cancer which they alleged was linked to the company’s talcum powder. 

The company was appealing a 2018 court ruling in favor of 22 women who alleged asbestos-contaminated talcum powder was linked to their cases of ovarian cancer. The women had said the company did not provide adequate warning of the risks associated with using their products. The initial settlement amount had initially been over $4 billion before being cut down.

The judge in that case ruled Johnson & Johnson had “misrepresented the safety of these products for decades” and the evidence shown at the trial demonstrated “particularly reprehensible conduct on the part of Defendants.”
Johnsons & Johnson has dominated the talcum powder market for over a century.
While there is no established link between talcum powder exposure and cancer, but talcum powder is often mined close to asbestos, a known carcinogen for which there is no safe level of exposure, and which can have a long latency period between exposure and cancer development.
Some studies have shown an increase in lung cancer risk for miners working underground when exposed to raw talc, which can be contaminated with asbestos, while others have found no effect. Use of talcum powder in the genital or perineal area is thought to contribute to ovarian cancer risk, but results are also mixed.
Companies have been directed not to use asbestos in cosmetic products since the 1970s, according to the American Cancer Society. According to the National Cancer Institute, “the weight of evidence does not support an association between perineal talc exposure and an increased risk of ovarian cancer.”


A 2018 investigation by Reuters uncovered documents showing that Johnson & Johnson was not only aware of the asbestos contamination problem, the company covered it up. It even tried to influence US regulatory policy over asbestos in cosmetic products. Lawyers representing the company have argued in court that the tests were unreliable, although recent independent lab tests of samples obtained from various time periods detected asbestos contamination.

In response to queries from Reuters, Johnson & Johnson’s outside litigation counsel Peter Bicks wrote: “The scientific consensus is that the talc used in talc-based body powders does not cause cancer, regardless of what is in that talc. This is true even if – and it does not – Johnson & Johnson’s cosmetic talc had ever contained minute, undetectable amounts of asbestos.”

Source: Forbes