IEDCR and icddr,b study finds Saliva as an alternative specimen for detection of Covid-19

As the COVID-19 pandemic erupted, World Health Organization (WHO) recommended the use of nasopharyngeal swab or throat swab for detection of SARS-CoV-2. Collection of nasopharyngeal swab causes discomfort to the person due to invasive collection procedure. There are considerable risks to the healthcare worker while collecting these specimens. Considering all these, an alternative, non-invasive, reliable and self-collected specimen was explored by Institute of Epidemiology, Diseases Control and Research (IEDCR) and International Center for Diarrhoeal Disease Research, Bangladesh (icddr,b). The objective of the study was to investigate the suitability of saliva over the nasopharyngeal swab of suspected COVID-19 patients for detection of SARS-CoV-2. A total of 596 participants including suspected COVID-19 patients and their contacts were chosen. Both nasopharyngeal swab and saliva were collected from each of these participants at the Coronavirus Facility of Dhaka Hospital, icddr,b. Fever, altered smell and loss of appetite were significantly observed as COVID-19 symptoms among the studied participants. Data was analyzed to determine the positivity of nasopharyngeal swab and saliva, and detection of viral load in these specimens. Considering the RT-PCR results as a reference standard, it was found that the sensitivity of saliva specimen is 80.35% which meets the WHO criteria. However, the viral load was higher among the nasopharyngeal swab compared to saliva samples. The study found - saliva is an easy-to-get, convenient and low-cost specimen to diagnose COVID-19 compared to nasopharyngeal swab. Saliva yields better results if it is collected within the first five days of the onset of the symptoms. Saliva samples can be collected from home safely. Hence, there is no need to travel to sample collection points. Self-collected saliva can reduce the cost of sample collection kit as well as minimize sample collection related risk of infection. Other studies conducted in different countries also found similar sensitivity. USFDA has approved this testing method (Saliva Direct) based on analyzing saliva samples. France and Singapore's Health Sciences Authority have approved the method too while many other countries are also evaluating saliva testing as an option for diagnosing COVID-19.

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Advances engineered heart tissue technology

Efforts to understand cardiac disease progression and develop therapeutic tissues that can repair the human heart are just a few areas of focus for the research group. The group's latest dynamic model, created in partnership with collaborators in the Netherlands, mimics physiologic loads on engineering heart muscle tissues, yielding an unprecedented view of how genetics and mechanical forces contribute to heart muscle function. Hemodynamic loads, or the preload and afterload are important not only for healthy heart muscle function, but can also contribute to cardiac disease progression. Preload and afterload can lead to maladaptive changes in heart muscle, as is the case of hypertension, myocardial infarction, and cardiomyopathies. In new research group introduces a system comprised of engineered heart muscle tissue (EHT) that is attached to an elastic strip designed to mimic physiologic preloads and afterloads. This first model shows that recreating exercise-like loading drives formation of more functional heart muscle that is better organized and generates more force each time it contracts. However, using cells from patients with certain types of heart disease, these same exercise-like loads can result in heart muscle dysfunction. Arrhythmogenic cardiomyopathy (ACM) that often becomes worse with exercise. Researcher have been able to get patient-specific induced pluripotent stem cells, differentiate these into heart muscle cells, and then use these in our new EHT model to recreate ACM in a petri dish. Looking to the future, the collaborators aim to use their model and findings to study a wide range of other heart diseases with genetic mutations, develop new therapeutic treatments and test drugs to gauge their effectiveness.

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Structures discovered in brain cancer patients can help fight tumors

Researchers have discovered lymph node-like structures close to the tumor in brain cancer patients, where immune cells can be activated to attack the tumor & also found that immunotherapy enhanced the formation of these structures in a mouse model. This discovery suggests new opportunities to regulate the anti-tumor response of the immune system. Glioma is a deadly brain tumor with a dismal prognosis. One reason why brain tumors are very hard to treat is that our immune system, which is designed to detect and destroy foreign cells including cancer cells, cannot easily reach the tumor site due to the barriers that surround the brain. To fight a developing tumor, killer immune cells such as T lymphocytes must be activated and primed in our lymph nodes, before travelling to the tumor site to effectively kill the cancer cells. Because of the barriers around the brain, it is a challenging process for T lymphocytes to reach the tumor. In the study the researchers describe their discovery of structures similar to lymph nodes in the brain where T lymphocytes could be activated. Researcher said that it was extremely exciting to discover for the first time the presence of lymph node-like structures in glioma patients. These structures are known as tertiary lymphoid structures (TLS) and they are not found in healthy individuals. They have all the components needed to support lymphocyte activation on-site which means that they could have a positive effect on the anti-tumor immune response. The researchers also showed that the formation of TLS in the brain can be induced by a type of immunotherapy in glioma-bearing mice. Indeed, when they treated the mice with immunostimulatory antibodies called αCD40, the formation of TLS was enhanced and always occurred in proximity to tumors. αCD40 is currently being tested to treat brain tumors in a number of clinical trials. In the study, the researchers found that while αCD40 boosted TLS formation, it also counterproductively inhibited the tumor-killing ability of the T lymphocytes. The study has therefore provided important insights into the multifaceted effects of αCD40 therapy.

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New Products of SQUARE Pharmaceuticals Ltd.

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