Tag: Medicine

Tel Aviv University researchers have found that our body’s natural defenses can help destroy malignant tumors. The team found that white blood cells called ‘eosinophils’ fight cancer in two ways: they can destroy the cancer cells themselves, and also recruit the immune system’s cancer-fighting T-cells – another type of white blood cells key to protecting the body against infection. These findings may contribute to the development of new immunotherapies.

Fighting Cancer from Within

The discovery comes as the rising number of cancer cases every year has contributed to a boom in immunotherapy, a treatment that activates the body’s immune system to fight disease. Compared to traditional techniques like chemotherapy, immunotherapy generally leads to longer protection from cancer and fewer side effects.

“Enhancing the number and power of T-cells is one of the main targets of immunotherapy treatments administered to cancer patients today,” said lead researcher, Prof. Ariel Munitz of TAU’s Department of Microbiology and Clinical Immunology at the Sackler Faculty of Medicine. “We discovered a new interaction that summons large quantities of T-cells to cancer tissues, and our findings may have therapeutic implications. Ultimately, our study may serve as a basis for the development of improved immunotherapeutic medications that employ eosinophils to fight cancer.”

Repurposing Cells’ “Destructive” Qualities

Eosinophils produce powerful destructive proteins originally intended for fighting parasites. However, in the modern Western world, where high levels of hygiene have significantly reduced the risk of many parasites, eosinophils often have a negative impact on humans, inducing phenomena like allergies and asthma.

Considering the destructive power of eosinophils, the researchers decided to test the potential benefits of these white blood cells if turned against cancer cells.

For two main reasons, they decided to focus their study on lung metastases, or cancer that started in another part of the body and spread to the lungs: “First, metastases, and not the primary tumors, are often the main problem in treating cancer. The lungs are a major target for the metastasis of many types of cancer,” said Prof. Munitz. “Second, in a preliminary study we demonstrated that eosinophils gather in tumors developing in mucous tissues like the lungs, and therefore assumed that they would be found in lung metastases as well.”

Summoning Reinforcement

The researchers examined tissue samples taken from breast cancer patients. They found that the eosinophils reach the lungs and penetrate the cancer tissues, where they often release their destructive proteins and summon T-cells for reinforcement. Ultimately, T-cells gather in the affected lungs, slowing the growth of tumors.

Additionally, the researchers found that in the absence of eosinophils, the lung tumors were much larger than those exposed to the white blood cells. These findings led to the conclusion that eosinophils fight cancer effectively.

Along with Prof. Munitz, the study was led by TAU PhD student Sharon Grisaru. The findings were published in the journal Cancer Research, published by the American Association for Cancer Research. The initiative was funded by ICRF (Israel Cancer Research Fund), the Israel Cancer Association, ISF (the Israel Science Foundation) BSF (U.S.-Israel Binational Science Foundation) and GSK.  

Featured image: Illustration: Eosinophil, a white blood cell in 3D

Approximately 50 million people worldwide live with Alzheimer’s or other related forms of dementia. Alzheimer’s disease leads to memory loss and impairment in cognitive function, and is the most common cause of dementia among older adults. While certain treatments can help reduce symptoms and sometimes reduce disease progression, there is currently no way to prevent or cure Alzheimer’s.

Amid that backdrop, researchers from Tel Aviv University have developed a process for reversing the precursors of the disease, providing a promising foundation for new preventative therapies. This marks the first time that a non-drug therapy has proven effective in preventing the core biological processes that lead to the development of Alzheimer’s, providing hope that we will now be able to fight one of the greatest challenges to the Western world.

Targeting the Root of Alzheimer’s

Using hyperbaric oxygen therapy (HBOT), in which subjects breathe 100% oxygen in a special chamber of high atmospheric pressure, the researchers were able to reverse brain damages associated with the biological hallmarks of Alzheimer’s.

 “By treating the root problem that causes cognitive deterioration with age, we are in fact mapping out the way to prevention,” says co-lead researcher Prof. Shai Efrati.

Often used to treat carbon monoxide poisoning and infections that starve tissues of oxygen, hyperbaric therapy, when applied in a specific way, has previously been found capable of repairing damaged brain tissue and renewing growth of blood vessels and nerve cells in the brain. Therefore, the researchers tested its potential for Alzheimer’s.

“After a series of hyperbaric treatments, elderly patients who were already suffering from memory loss showed an improvement of blood flow to the brain as well as a real improvement in cognitive performance,” said co-lead investigator Prof. Uri Ashery.

The new approach devised by the researchers unequivocally improved characteristics commonly associated with Alzheimer’s disease. Specifically, the hyperbaric treatment resulted in:

• Improved memory in 16.5% of patients on average
• Increased blood flow in 16%-23% of cases
• Improved attention and concentration in 6% of patients
• Improved information processing speed in 10.3% of all cases

A Future Without Alzheimer’s?

 “Our findings provide hope that we will now be able to fight one of the greatest challenges to the Western world. According to our findings, hyperbaric therapy given at a young age is likely to prevent this severe disease entirely,” explains TAU team member Dr. Ronit Shapira.

The approach was first tested in laboratory settings followed by testing in patients over the age of 65 in stages of deteriorating mental function that often precede Alzheimer’s and dementia. The therapy included a series of 60 treatments in hyperbaric chambers over a period of 90 days.

The study is part of a comprehensive research program focused on reversing processes of aging and its accompanying ailments. The researchers note that the findings are an encouraging step toward new approaches to preventing Alzheimer’s by addressing not only the symptoms or targeting biomarkers, but the core pathology and biology responsible for the disease’s development.

The Tel Aviv University team that led the study included Prof. Shai Efrati of the Sackler Faculty of Medicine and the Sagol School of Neuroscience, Prof. Uri Ashery and  Dr. Pablo Blinder of the The George S. Wise Faculty of Life Sciences and the Sagol School of Neuroscience, and Dr. Ronit Shapira and Dr. Amir Hadanny. They are all affiliated with the Shamir Medical Center. The findings were published in the journal Aging.

Featured image: Alzheimer’s Disease on MRI

Warnings against the dangers of smoking can be read on every cigarette box and in every advertisement for smoking brands. Those who smoke endanger themselves and also those around them, who inevitably become passive smokers. This way, parents who smoke harm the health of their own children. A first-of-its-kind study in Israel by researchers from the Sackler Medical School of Tel Aviv University uncovers alarming data about secondhand smoking by children of smokers: According to the study, nicotine residues were found in the hair samples of 7 out of 10 children who participated. The research team found that parental behavior may be changed through regular monitoring of children’s exposure.

Nicotine Residue in Children’s Hair

The study was conducted under the leadership of a team of experts from the Tel Aviv University School of Medicine headed by Prof. Leah (Laura) Rosen of the School of Public Health together with researchers Dr. Vicki Myers, Prof. Nurit Guttman, Ms. Nili Brown, Prof. Mati Berkovitch, and Dr. Michal Bitan. Prof. David Zucker of the Hebrew University of Jerusalem and Dr. Anna Rule of Johns Hopkins University in the US also participated in the study. The study was published in the prestigious journal, Nicotine & Tobacco Research.

In the study, the researchers sought to examine whether raising awareness of children’s exposure by providing objective feedback might change the parents’ behavior and child exposure. 140 Israeli families participated in the study, parents of children up to age 8, at least one parent being a smoker. The smoking average per household was 15 cigarettes per day, where one third of the respondents reported that they smoke inside the home, and one third said that they smoke on the terrace but not inside the home.

First, researchers tested children’s level of exposure via a biomarker, nicotine in hair, which indicates cumulative exposure to tobacco smoke. The researchers took hair samples from the children and tested the nicotine levels in each sample (it is important to note that the test was for nicotine that became an integral part of the strand of hair and not just outside precipitate.) The findings were very concerning: Nicotine residue was found in the hair of 70% of the children tested. Only 29.7% of the children tested did not show nicotine residue in their hair samples. 

The researchers divided the families into two groups: one group underwent comprehensive instruction about the effects and dangers of exposure to smoking, including feedback and information about the test results. The group was also given tools to protect their children from exposure to cigarette smoke and a recommendation to keep their home and car smoke-free. The second group received feedback about nicotine levels in the children’s hair after six months, at the end of the study.

Limiting Children’s Exposure

Six months after the start of the study, the researchers conducted additional nicotine tests on the children’s hair, and one could already see a significant improvement in the data: Among the group that received comprehensive training, the percentage of children whose hair samples contained nicotine decreased from 66% to 53%, whereas in the second group (which did not receive training at the start of the study), the percentage of children whose hair samples contained nicotine decreased from 74% to 49%. Thus, just testing the children, without even informing families of the results, was enough to seemingly change parents’ behaviors.

The researchers theorize that the knowledge that the children were tested for tobacco smoke exposure, and that additional testing was planned at six months, resulted in the parents changing their behavior and reducing the children’s exposure. As a result of the study’s findings, the researchers recommend considering conducting such testing to measure exposure on a routine basis among young children in Israel.

The Right to Breathe Smoke-Free Air

Prof. Leah Rosen: “To our great dismay, according to the Ministry of Health’s data, approximately 60% of small children in Israel are exposed to secondhand smoke and its harmful effects. Based on the study’s findings, we believe that conducting nicotine testing – in the hair, urine, or using other testing methods – for every young child in Israel, may change parents’ perceptions about exposing their children to tobacco smoke. Changing this perception can also result in changing behavior, exposure levels, and even social norms regarding passive exposure to smoking – both exposure of children as well as exposure of adults.”

“We call upon smokers to avoid smoking anyplace where non-smokers and in particular, at-risk populations, including children, pregnant women, elderly, and those who are ill, could be exposed. Non-smokers must understand that there is genuine risk in exposure to tobacco smoke, and they must insist upon their right and the right of their children and family members to breathe air that is smoke-free everywhere. Of course, the government has a central role in enforcing laws pertaining to smoking in public places and continuing to enact laws to protect the individual everywhere from exposure to secondhand smoke.” 

Any Tel Avivian will tell you that the perfect place for a first date is at the beach. Now, we have the science to support that claim. Researchers at Tel Aviv University have found that exposure to ultraviolet radiation from sunlight enhances romantic passion in humans. In the study, men and women were exposed to UVB (ultraviolet radiation type B) under controlled conditions, and the findings were unequivocal: increased levels of romantic passion in both genders.

Sun + Skin = Love

The study revealed that exposure to sunlight affects the regulation of the endocrine system responsible for the release of sexual hormones in humans. The discovery may lead to practical applications down the line, such as UVB treatments for sexual hormone disorders.

In animal models, the effect was dramatic: the females’ hormone levels rose significantly, enlarging their ovaries and prolonging their mating season; the attraction between males and females increased; and both were more willing to engage in sexual intercourse.

The researchers repeated the experiment on the animal model, this time removing from the skin a protein called p53, which identifies DNA damage and activates pigmentation during exposure to sunlight as protection against its adverse effects. The removal of the protein eliminated the effect of UVB exposure on the animals’ sexual behavior, convincing the researchers that exposure to radiation through the skin was the cause of the observed hormonal, physiological and behavioral changes, and that the protective system is also responsible for the regulation of sexuality.

Furless Humans and Sun Exposure

In the 32 human subjects of the study, all treated with UVB phototherapy at the Tel Aviv Sourasky (Ichilov) and Assuta Medical Centers, both genders exhibited a rise in romantic passion, and males also noted an increase in levels of aggression.

Similar results were found when the subjects were asked to avoid sunlight for two days, and then tan themselves for approximately 25 minutes. Blood tests revealed that exposure to sunlight resulted in a higher release of hormones like testosterone compared to one day before exposure. A rise in testosterone in males during the summer was also found in analyses of data from the Israeli health maintenance organizations Clalit and Maccabi Health Services.

Prof. Carmit Levy (on the left) & PhD student Roma Parikh.

The new discovery from TAU may lead to future practical applications, such as UVB treatments for sexual hormone disorders. The breakthrough opens up for further discoveries in basic science, “As humans, we have no fur, and our skin is thus directly exposed to sunlight. We are only beginning to understand what this exposure does to us, and the key roles it might play in various physiological and behavioral processes. It’s only the tip of the iceberg,” says Prof. Carmit Levy from the Department of Human Molecular Genetics and Biochemistry at the Sackler Faculty of Medicine.

The study was led by PhD student Roma Parikh and Ashchar Sorek from the laboratory of Prof. Levy. UVB phototherapy was administered to the subjects at the Tel Aviv Sourasky (Ichilov) and Assuta Medical Centers. The groundbreaking discovery was published as a cover story in the prestigious scientific journal Cell Reports. 

A team led by Tel Aviv University identified a new indicator of metastatic breast cancer, laying the groundwork for preventive treatment that could save millions of lives.

Metastatic breast cancer, also known as Stage 4 breast cancer, occurs when cancer has spread, or “metastasized,” to other parts of the body. Mortality from breast cancer is almost exclusively a result of tumor metastasis, and lungs are one of the main metastatic sites. The five-year survival rate for women with metastatic breast cancer is estimated at 28%.

Investigating The “Black Box” of Breast Cancer 

“Breast cancer patients, as well as patients with many other types of cancer, do not die from the primary tumor, but from distant metastases which have developed, sometimes after years, in essential organs such as the lungs and brain,” said the study’s lead researcher, Prof. Neta Erez, Chair of the Department of Pathology at TAU’s Sackler Faculty of Medicine. “Understanding the body’s preparation for the reception of metastases at an early stage may save millions of lives.”

The researchers explain that metastases can appear several years after the initial cases are treated. Today, methods used for follow-up screening identify metastases only when they are quite large–when the disease is at an advanced stage and unlikely to be cured.

For this reason, Erez’s research group is investigating the black box—the time period between apparent recovery and the appearance of metastases to understand the metastatic process and to find ways of blocking it in early stages. Their research in recent years has revealed that certain tissues, in organs where the metastases are set to arrive, “prepare the area” for reception and produce a hospitable environment for them, a long time before the appearance of the metastases themselves. In the present study, the research team searched for signs of these changes, which may be used in the future to identify the start of the process that predicts metastases. The researchers identified these changes in the area known as “the micro-environment” of the tumor, and specifically in connective tissue known as fibroblasts which are found in the lungs among other places. 

“In a normal situation, fibroblasts play a central role in healing wounds and injury to the lungs, but recent studies revealed that cancer is successful in recruiting them and causing them to produce a supportive environment for it,” said Erez.

What is Happening in the Micro-environment of the Metastases?

The researchers compared genes sequenced from healthy lungs, from lungs with micro-metastases (very small metastases which cannot be identified using existing clinical tools) and from lungs with large metastases, in a state of advanced disease.

By identifying and comparing the respective development in the three different types of sample tissues, the researchers succeeded, for the first time, in characterizing the process that occurs in the micro-environment of the metastases. The findings provide valuable understanding about how cancer cells grow, which can then be leveraged for detection by existing imaging methods and treated to prevent metastasis.

The study’s leading research team from Erez’s laboratory included Dr. Ophir Shani and Dr. Yael Raz along with additional researchers from Tel Aviv University, Sheba Medical Center at Tel HaShomer, Tel Aviv Sourasky Medical Center (Ichilov Hospital), and the Weizmann Institute of Science. The findings were published in the prestigious peer-reviewed journal eLife.  

As experts continue to learn more about immune responses to COVID-19 and the effectiveness of vaccines, researchers from Tel Aviv University have contributed a new piece to the puzzle. A joint study conducted by researchers from TAU and the Shamir Medical Center (Assaf Harofe) indicates that the level of antibodies changes according to age groups, gender, symptoms, and time elapsed since vaccination. The findings are the latest from the researchers in a series of studies aimed at providing reliable measures on the effectiveness of COVID-19 vaccination.

The new study examined the level of antibodies in over 26,000 blood samples taken from COVID-19 convalescents, as well as vaccinated and unvaccinated individuals.

In vaccinated individuals, the researchers found differences between women and men in the concentration of antibodies in the blood relative to both age and gender. In women, the level of antibodies begins to rise from the age of 51, and is higher than the levels found in men of similar age. This phenomenon may be related change in levels of the estrogen hormone, observed around this age, which affects the immune system. In men, a rise in antibody levels is seen at an earlier age, starting around 35, and may be related to changes in levels of testosterone and the effect on the immune system.

In young adults, a high concentration of antibodies generally signals a strong healthy functioning immune response, while in older demographics it typically indicates overreaction of the immune system associated with severe illness. In general, young adults were found to have a higher level of antibodies sustained for a longer period of time compared to older vaccinated persons. The findings further validate existing evidence that, depending on age, higher antibody count isn’t necessarily equivalent to higher rates of recovery.

Furthermore, the study found that the immune response of vaccinated individuals (after two doses) is much stronger than that of people who have recovered from COVID-19. The findings show that vaccinated individuals have four times the level of antibodies compared to convalescents.

The study was conducted by Tel Aviv University’s Prof. Noam Shomron, Head of the Computational Genomics Laboratory at the Sackler Faculty of Medicine and a member of the Edmond J. Safra Center for Bioinformatics and Dr. Adina Bar Chaim from the Shamir Medical Center. The data were collected by Dr. Ramzia Abu Hamad from the Shamir Medical Center, and analysis was conducted by Guy Shapira, a PhD student at Prof. Shomron’s laboratory. The study was published in Medrxiv.