(Press-News.org) Australian scientists researching how our immune system responds to COVID-19 have revealed that those infected by early variants in 2020 produced sustained antibodies, however, these antibodies are not as effective against contemporary variants of the virus.
The research is one of the world's most comprehensive studies of the immune response against COVID-19 infection. It suggests vaccination is more effective than the body's natural immune response following infection and shows the need to invest in new vaccine designs to keep pace with emerging COVID variants.
Published today in PLOS Medicine, the study was made possible by a partnership between the University of Sydney, Kids Research, Sydney Children's Hospitals Network, the Kirby Institute at UNSW Sydney, Australian Red Cross Lifeblood, St Vincent's Hospital and NSW Health Pathology, as well as other local and international collaborators.
The team analysed the serum of 233 individuals diagnosed with COVID-19 over 7 months and uncovered that the level of immunity over time is dependent on disease severity and the viral variant. They show that antibodies developed during the first wave had reduced effectiveness against six variants, ranging from those observed in the second wave in Australia through to three variants of concern that have driven the global pandemic in the UK, Brazil and South Africa.
How do we study the immune response?
The serum of COVID-19 infected individuals was of interest as it is the part of our blood that contains crucial information about our immune system. Analysis of the serum made it possible to create a detailed timeline of the level of 'neutralising antibodies' produced against COVID-19 infection, and so to see if there was long-term immunity.
Neutralising antibodies are part of our immune system's frontline arsenal that is triggered during infection and vaccination. Their job is to shield cells that are usually the target of a pathogen (such as the SARS-CoV-2 virus which causes the COVID-19 disease) from being infected. The level of neutralising antibody response can be a defining feature of how effectively our body fights off illness.
Interestingly, a rare group of 'super responders' was also identified as an exception.
This group of 'super responders' had a stable and robust level of antibodies across all COVID-19 variants. The researchers say this group could prove useful for investigating the potential of convalescent plasma (using blood from people who have recovered to treat others) which has so far proven ineffective against severe COVID-19 illness. In addition, key donors could be looked at closely and their antibodies cloned for future therapeutic use.
Why it is important?
Co-senior author Associate Professor Fabienne Brilot of the University of Sydney and Kids Research, Sydney Children's Hospitals Network, and her research team led the analysis branch of the study, using highly sensitive tools they developed to study the antibodies in detail.
"We can learn a great deal from these people who were infected in the first wave in Australia as they were infected with the same variant that our current vaccines are based on," said Associate Professor Brilot.
"While the approved vaccines are showing good responses, our study highlights the importance of continued vaccine development, especially taking into account the differences in variants."
Co-senior author Associate Professor Stuart Turville of the Kirby Institute said the study was conducted to investigate the level, breadth and longevity of the immunity generated from COVID-19 infection and whether mutation of the virus compromises immunity.
"What this work has shown us is that current observations about vaccines show they offer a much broader protection against COVID-19 and its variants than the body's natural immune response following infection, which is usually only protective against the variant of the virus that the person was infected with. We, therefore, should not rely on the body's natural immune response to control this pandemic, but rather the broadly protective vaccines that are available."
Key findings
SARS-CoV-2 antibody responses are sustained for up to seven months post-infection.
The immune response remained stable in some individuals, and while it decreased in others, no individual showed a negative response during the seven-month period.
Levels of virus-neutralising antibodies were associated with COVID-19 severity.
Antibodies generated after early infection displayed a significantly reduced antibody binding and neutralisation potency to globally emerging viral variants.
Methods
The study analysed the serum from 233 individuals who were diagnosed with COVID-19 from February to October 2020. There were two cohorts to the study--a hospital-based cohort of patients (the ADAPT study at St Vincent's Hospital, Sydney) recruited during the first and second wave of infection in Australia and a national cohort of plasma donors (LIFEBLOOD).
10 COVID-19 strains and variants of concern/ interest were investigated, including:*
First known classified SARS-CoV-2 strain (Wuhan -1 D614)
Alpha (B.1.1.7, United Kingdom)
Beta (B.1.351, South Africa)
Gamma (P1, Brazilian)
Zeta (P2, Brazilian)
*Note naming conventions updated to reflect World Health Organisation classifications
The researchers used a comprehensive suite of assays that measured:
The longevity and type of antibody response against Spike from various variants over time in serum of COVID-19 diagnosed individuals.
Neutralisation of infectious SARS-CoV-2 over time, by infecting cell lines that had ACE2 on its surface (which SARS-CoV-2 binds and targets on the cell to begin infection) with a particle designed to mimic a version of the SARS-CoV-2 virus particle.
INFORMATION:
The study of many global viral variants was made possible by the key collaboration between NSW Health Pathology and The Kirby Institute. The latter team engineered cells to rapid catch virus from swabs that were acquired and rapidly sequenced by the team at Prince of Wales headed by Professor William Rawlinson.
Co-first author Fiona Tea who completed the research as part of her early postdoctoral fellowship at the University of Sydney and Kids Research at the Children's Hospital at Westmead said: "What makes this study stand out is the level and depth of analysis to neutralising antibody levels in people recovering from COVID infection over time, including comparison of infection recovering from different viral variants."
Declaration: This work was supported by Snow Medical and various grants including two NSW Health COVID-19 Research Grants and multiple grants from the Australian Government's Medical Research Future Fund (MRFF), among others. Refer to the paper for full details. Associate Professor Brilot has received honoraria from Biogen Idec and Merck Serono as an invited speaker. All other authors declare no competing interest. Ethics approval for this study was granted by St Vincent's Hospital (2020/ETH00964) and Lifeblood (30042020) Research Ethics Committees.
Polymer composite materials that combine magnetic and electrical properties are the subjects of particular attention for modern-day researchers. Their basic property is the ability to convert electric polarization into a magnetic field and vice versa. Although some materials exhibit a much better magnetoelectric effect, polymer-based composites are easier not only to produce but also to modify.
Such composites have great potential in a variety of different fields. For example, using them as a basis, scientists can develop surfaces that help cultivate various cells. In this case, polymer composites serve as a substrate through which it is possible to affect the culture using a non-contact and controlled electric charge and morphological properties ...
DANVILLE, Pa. - Having multiple chronic health conditions and living in a rural area were the top two factors affecting increased healthcare system contact among older patients with bladder cancer, a research team has found.
The Geisinger-led team evaluated 73,395 Medicare beneficiaries age 66 and older who had been diagnosed with non-muscle-invasive bladder cancer to assess their treatment burden, defined as the number of days the patients had contact with a health system in the year following diagnosis.
Nearly two-thirds of the patients had multiple co-existing chronic conditions at the time of bladder cancer diagnosis, as well as other aging-related conditions, including a history of falls, ...
Opioid prescribing preferences and practices among surgical residents and faculty differ, according to a new study published in the journal Surgery.
The study, titled "Evaluation of opioid prescribing preferences among surgical residents and faculty," was based on a survey of 56 residents and 57 faculty within the University of Colorado School of Medicine Department of Surgery. In the survey, participants were asked how many oxycodone tablets they would prescribe for 14 common surgical procedures.
Answers were compared between residents and faculty, as well as against the Opioid Prescribing Engagement Network (OPEN) guidelines and actual opioids ...
A new screening method that can test the effectiveness of therapeutic molecules designed to 'glue' proteins together in the body has been developed by researchers at the University of Birmingham and the University of Leicester.
The research paves the way for drug developers to screen large numbers of potential new drug compounds to discover new treatments for diseases such as breast cancer and Parkinson's disease.
The ways in which proteins interact with each other are fundamental to all cell functions. These interactions underpin every function of a healthy body, with any slight change in these interactions resulting in disease.
A handful ...
Scientists at the University of Cambridge have identified rare genetic variants - carried by one in 3,000 people - that have a larger impact on the risk of developing type 2 diabetes than any previously identified genetic effect.
Type 2 diabetes is thought to be driven in part by inherited genetic factors, but many of these genes are yet unknown. Previous large-scale studies have depended on efficient 'array genotyping' methods to measure genetic variations across the whole genome. This approach typically does a good job at capturing the common genetic differences between people, though individually these each confer only small increases in diabetes ...
DALLAS, July 7, 2021 -- Myocarditis in children is a rare yet challenging condition to treat. Diagnosis and treatment includes multiple options, and many cases of myocarditis resolve on their own, according to a new scientific statement from the American Heart Association, "Diagnosis and Management of Myocarditis in Children," published today in Circulation, the Association's flagship journal. The scientific statement writing group reviewed the latest research to develop guidance in diagnosis and treatment for myocarditis in children.
Myocarditis is inflammation of the middle layer of the wall of the heart muscle, the myocardium, and it ...
The newly developed method lets researchers rapidly and accurately measure stress hormones in snow leopards without the need for bulky equipment or specialised knowledge. It uses widely available equipment that can be carried into the field, allowing hormone extraction from faecal samples and analysis to be done on site.
This differs from existing approaches to hormone monitoring in wild animals, where faecal samples must be taken to laboratories for hormone extraction and analysis. These approaches are particularly limiting in remote locations, such as the Himalayas.
"Because conventional hormone monitoring methods require frozen and refrigerated chemical reagents, and laboratory equipment, it is almost impossible to use them on-site." explained ...
CLEVELAND, Ohio (July 7, 2021)--Estrogen has been thought to play a role in a woman's risk of developing Alzheimer disease (AD). A new study has taken a different approach to identifying risk factors for AD by examining the association between a woman's reproductive life span as an indicator of endogenous estrogen exposure and levels of cerebrospinal fluid biomarkers. Study results are published online in Menopause, the journal of The North American Menopause Society (NAMS).
Alzheimer disease represents 60% to 70% of all dementia diagnoses, making it the most common form of dementia. Approximately ...
A new study in the Journal of the European Economic Association, published by Oxford University Press, finds that electoral districts with a larger gender pay gaps show favoritism toward male political candidates in Parliamentary elections, with fewer female candidates on the ballot.
The researchers here gathered data for seven parliamentary elections in France between 1988 and 2017. Researchers studied candidates from the Left and Right political coalitions, which account for 80% of elected members of Parliament. The researchers consulted administrative and web data on candidates and electoral outcomes, survey data on ...
Oncotarget published "Association between miRNA signatures in serum samples from epidermal growth factor inhibitor treated patients and skin toxicity" which reported that on average 70% of patients treated with EGFRIs suffer from skin toxicity.
Studies showed a correlation between overall survival and the appearance of a skin rash, which is used as a biomarker for therapy efficacy.
In this study, the authors searched for associations of miRNA expression profiles in serum, with the severity of skin rash, in order to identify tentative therapy predictive biomarkers.
In this cohort of patients treated with EGFR inhibiting monoclonal antibodies, miR-21 and miR-520e serum concentrations were negatively correlated with severity of skin rash whereas for miR-31, a positive correlation was ...
