Latest news with #immuneResponse
Yahoo
05-07-2025
- Health
- Yahoo
The 1 Thing You Should Never, Ever Do If You Get A Mosquito Bite
Every summer, I get eaten alive by mosquitoes. My arms and legs get covered in bites that I scratch until they become bloody bruises that scab over and take weeks to heal. I know I'm treating my mosquito bites all wrong because, well, I have the scars to show it. Most mosquito bites go away within a week or so ― unless you don't take proper care of them. According to the Centers for Disease Control and Prevention, when you get bit by a mosquito, the bug injects saliva into your body via its proboscis, the little needle-like body part that sucks up your blood. That saliva contains an anticoagulant that keeps your blood flowing so the bug can get a hearty meal to lay its eggs. The toxins in that saliva are thought to be what makes their bites feel warm and itchy. Dr. Bobbi Pritt, the director of the Clinical Parasitology Laboratory at Mayo Clinic and a spokesperson for the College of American Pathologists, said this is because your body mounts an immune response to the saliva and releases a wave of histamines and leukotrienes. This reaction varies from person to person, and bug to bug, which is why some people develop significant swelling and soreness while others just get a mildly itchy bump. Regardless of how you react to mosquito bites, doctors agree there's one thing you shouldn't do when you get a bite: scratch it. It can be tempting to scratch mosquito bites given how incredibly itchy they can get, but you really want to avoid doing so, Pritt said. The main reason: There are many different types of bacteria that live on our skin and our bodies — like Staphylococcus and Streptococcus — that, for the most part, are harmless, according to Pritt. 'But if you have an open wound, like if you scratch really hard, you could actually rub the bacteria from your skin into that little wound and get an infection.' These infections, like cellulitis and impetigo, can cause redness, swelling, a blister, tenderness around the bite along with swollen lymph nodes and yellow discharge. They can be treated with antibiotics, but, in rare cases, an infected bite can lead to serious complications like sepsis or necrotizing fasciitis. The second reason you don't want to scratch: The more you itch, the more histamine cells your body will release, making the bite even itchier. 'Scratching can send mild pain signals to the brain, which can release serotonin and increase the sensation of itching,' said Pamela Frable, an associate professor at TCU's Harris College of Nursing and Health Sciences. Of course, not scratching isn't the only way to speed up your recovery, and there are a few other steps you want to take to prevent infection and make sure your bite gets better. The very first thing you want to do after you get bit is wash the bite out with soap and water. This will help remove bacteria near the bite that could cause an infection. A mosquito bite is technically a small wound, said Frable, and 'it's generally a good idea to wash all wounds gently with soap and water.' Then, you want to apply ice to the bite, ideally for about 10 minutes or so, Pritt explained. Ice can drastically reduce the itching along with inflammation, pain and swelling, according to the Cleveland Clinic. Next up: Cover the bite with an anti-itch or antihistamine cream, such as calamine lotion or hydrocortisone. These products can drastically reduce itchiness and, most importantly, prevent you from scratching the bite and break the scratch-itch cycle, Pritt said. If you don't have these items in your medicine cabinet or aren't able to get to a pharmacy, you can whip up an anti-itch paste at home. Simply combine a tablespoon of baking soda with a splash of water to create a thick paste. Then, rub the mixture over the bite, wait 10 minutes, and wash it off. This DIY concoction reduces itch, according to the Mayo Clinic, but, better yet, it prevents you from scratching the bite and making things even worse. Finally, you want to keep an eye on the bite and pay attention to any symptoms you develop over the next week or two. It's fairly common to develop a fever or even swollen lymph nodes immediately after the bite, so don't panic if you experience these symptoms right away, Pritt said. Not all mosquitoes carry disease, but some spread Zika, dengue and West Nile virus, all of which can cause severe illnesses and health complications. You can't tell if a mosquito carried a pathogen by simply looking at the bite, according to Frable, which is why it's crucial to pay attention to any symptoms. So, if you get a fever, a rash, severe headache, or confusion a week or two after the bite, check in with a physician. They can run diagnostics tests to determine if you contracted a mosquito-borne disease and administer supportive care to help you recover. Fortunately, most mosquito bites resolve without any issues. But the less you itch and the better you take care of it, the sooner it'll clear up … until the next mosquito comes along. So THAT'S Why Mosquitoes Bite Some People More Than Others How To Tell If A Bug Bite Needs Medical Attention The Definitive Answer On Whether Bug Spray Is Bad For You
Yahoo
05-07-2025
- Health
- Yahoo
The 1 Thing You Should Never, Ever Do If You Get A Mosquito Bite
Every summer, I get eaten alive by mosquitoes. My arms and legs get covered in bites that I scratch until they become bloody bruises that scab over and take weeks to heal. I know I'm treating my mosquito bites all wrong because, well, I have the scars to show it. Most mosquito bites go away within a week or so ― unless you don't take proper care of them. According to the Centers for Disease Control and Prevention, when you get bit by a mosquito, the bug injects saliva into your body via its proboscis, the little needle-like body part that sucks up your blood. That saliva contains an anticoagulant that keeps your blood flowing so the bug can get a hearty meal to lay its eggs. The toxins in that saliva are thought to be what makes their bites feel warm and itchy. Dr. Bobbi Pritt, the director of the Clinical Parasitology Laboratory at Mayo Clinic and a spokesperson for the College of American Pathologists, said this is because your body mounts an immune response to the saliva and releases a wave of histamines and leukotrienes. This reaction varies from person to person, and bug to bug, which is why some people develop significant swelling and soreness while others just get a mildly itchy bump. Regardless of how you react to mosquito bites, doctors agree there's one thing you shouldn't do when you get a bite: scratch it. It can be tempting to scratch mosquito bites given how incredibly itchy they can get, but you really want to avoid doing so, Pritt said. The main reason: There are many different types of bacteria that live on our skin and our bodies — like Staphylococcus and Streptococcus — that, for the most part, are harmless, according to Pritt. 'But if you have an open wound, like if you scratch really hard, you could actually rub the bacteria from your skin into that little wound and get an infection.' These infections, like cellulitis and impetigo, can cause redness, swelling, a blister, tenderness around the bite along with swollen lymph nodes and yellow discharge. They can be treated with antibiotics, but, in rare cases, an infected bite can lead to serious complications like sepsis or necrotizing fasciitis. The second reason you don't want to scratch: The more you itch, the more histamine cells your body will release, making the bite even itchier. 'Scratching can send mild pain signals to the brain, which can release serotonin and increase the sensation of itching,' said Pamela Frable, an associate professor at TCU's Harris College of Nursing and Health Sciences. Of course, not scratching isn't the only way to speed up your recovery, and there are a few other steps you want to take to prevent infection and make sure your bite gets better. The very first thing you want to do after you get bit is wash the bite out with soap and water. This will help remove bacteria near the bite that could cause an infection. A mosquito bite is technically a small wound, said Frable, and 'it's generally a good idea to wash all wounds gently with soap and water.' Then, you want to apply ice to the bite, ideally for about 10 minutes or so, Pritt explained. Ice can drastically reduce the itching along with inflammation, pain and swelling, according to the Cleveland Clinic. Next up: Cover the bite with an anti-itch or antihistamine cream, such as calamine lotion or hydrocortisone. These products can drastically reduce itchiness and, most importantly, prevent you from scratching the bite and break the scratch-itch cycle, Pritt said. If you don't have these items in your medicine cabinet or aren't able to get to a pharmacy, you can whip up an anti-itch paste at home. Simply combine a tablespoon of baking soda with a splash of water to create a thick paste. Then, rub the mixture over the bite, wait 10 minutes, and wash it off. This DIY concoction reduces itch, according to the Mayo Clinic, but, better yet, it prevents you from scratching the bite and making things even worse. Finally, you want to keep an eye on the bite and pay attention to any symptoms you develop over the next week or two. It's fairly common to develop a fever or even swollen lymph nodes immediately after the bite, so don't panic if you experience these symptoms right away, Pritt said. Not all mosquitoes carry disease, but some spread Zika, dengue and West Nile virus, all of which can cause severe illnesses and health complications. You can't tell if a mosquito carried a pathogen by simply looking at the bite, according to Frable, which is why it's crucial to pay attention to any symptoms. So, if you get a fever, a rash, severe headache, or confusion a week or two after the bite, check in with a physician. They can run diagnostics tests to determine if you contracted a mosquito-borne disease and administer supportive care to help you recover. Fortunately, most mosquito bites resolve without any issues. But the less you itch and the better you take care of it, the sooner it'll clear up … until the next mosquito comes along. So THAT'S Why Mosquitoes Bite Some People More Than Others How To Tell If A Bug Bite Needs Medical Attention The Definitive Answer On Whether Bug Spray Is Bad For You
Yahoo
25-06-2025
- Health
- Yahoo
Mitochondria can sense bacteria and trigger your immune system to trap them – revealing new ways to treat infections and autoimmunity
Mitochondria have primarily been known as the energy-producing components of cells. But scientists are increasingly discovering that these small organelles do much more than just power cells. They are also involved in immune functions such as controlling inflammation, regulating cell death and responding to infections. Research from my colleagues and I revealed that mitochondria play another key role in your immune response: sensing bacterial activity and helping neutrophils, a type of white blood cell, trap and kill them. For the past 16 years, my research has focused on understanding the decisions immune cells make during infection and how the breakdown of these decision-making processes cause disease. My lab's recent findings shed light on why people with autoimmune diseases such as lupus may struggle to fight infections, revealing a potential link between dysfunctional mitochondria and weakened immune defenses. Neutrophils are the most abundant type of immune cell and serve as the immune system's first responders. One of their key defense mechanisms is releasing neutrophil extracellular traps, or NETs – weblike structures composed of DNA and antimicrobial proteins. These sticky NETs trap and neutralize invading microbes, preventing their spread in the body. Until recently, scientists believed that NET formation was primarily triggered by cellular stress and damage. However, our study found that mitochondria can detect a specific bacterial byproduct – lactate – and use that signal to initiate NET formation. Lactate is commonly associated with muscle fatigue in people. But in the context of bacterial infections, it plays a different role. Many bacteria release lactate as part of their own energy production. My team found that once bacteria are engulfed by a compartment of the cell called the phagosome, neutrophils can sense the presence of this lactate. Inside the phagosome, this lactate communicates to the neutrophil that bacteria are present and that the antibacterial processes are not sufficient to kill these pathogens. When the mitochondria in neutrophil cells detect this lactate, they start signaling for the cell to get rid of the NETs that have entrapped bacteria. Once the bacteria are released outside the cell, other immune cells can kill them. When we blocked the mitochondria's ability to sense lactate, neutrophils failed to produce NETs effectively. This meant bacteria were more likely to escape capture and proliferate, showing how crucial this mechanism is to immune defense. This process highlights an intricate dialogue between the bacteria's metabolism and the host cell's energy machinery. What makes this finding surprising is that the mitochondria within cells are able to detect bacteria trapped in phagosomes, even though the microbes are enclosed in a separate space. Somehow, mitochondrial sensors can pick up cues from within these compartments – an impressive feat of cellular coordination. Our study is part of a growing field called immunometabolism, which explores how metabolism and immune function are deeply intertwined. Rather than viewing cellular metabolism as strictly a means to generate energy, researchers are now recognizing it as a central driver of immune decisions. Mitochondria sit at the heart of this interaction. Their ability to sense, respond to and even shape the metabolic environment of a cell gives them a critical role in determining how and when immune responses are deployed. For example, our findings provide a key reason why patients with a chronic autoimmune disease called systemic lupus erythematosus often suffer from recurrent infections. Mitochondria in the neutrophils of lupus patients fail to sense bacterial lactate properly. As a result, NET production was significantly reduced. This mitochondrial dysfunction could explain why lupus patients are more vulnerable to bacterial infections – even though their immune systems are constantly activated due to the disease. This observation points to mitochondria's central role in balancing immune responses. It connects two seemingly unrelated issues: immune overactivity, as seen in lupus, and immune weakness like increased susceptibility to infection. When mitochondria work correctly, they help neutrophils mount an effective, targeted attack on bacteria. But when mitochondria are impaired, this system breaks down. Our discovery that mitochondria can sense bacterial lactate to trigger NET formation opens up new possibilities for treating infections. For instance, drugs that enhance mitochondrial sensing could boost NET production in people with weakened immune systems. On the flip side, for conditions where NETs contribute to tissue damage – such as in severe COVID-19 or autoimmune diseases – it might be beneficial to limit this response. Additionally, our study raises the question of whether other immune cells use similar mechanisms to sense microbial metabolites, and whether other bacterial byproducts might serve as immune signals. Understanding these pathways in more detail could lead to new treatments that modulate immune responses more precisely, reducing collateral damage while preserving antimicrobial defenses. Mitochondria are not just the powerhouses of the cell – they are the immune system's watchtowers, alert to even the faintest metabolic signals of bacterial invaders. As researchers' understanding of their roles expands, so too does our appreciation for the complexity – and adaptability – of our cellular defenses. This article is republished from The Conversation, a nonprofit, independent news organization bringing you facts and trustworthy analysis to help you make sense of our complex world. It was written by: Andrew Monteith, University of Tennessee Read more: Mitochondria keep your brain cells alive − helping them run smoothly may protect against Parkinson's disease More than half of US teens have had at least one cavity, but fluoride programs in schools help prevent them – new research When COVID-19 or flu viruses kill, they often have an accomplice – bacterial infections Andrew Monteith receives funding from the National Institute of Health.
The Independent
19-06-2025
- Health
- The Independent
Groundbreaking single-dose vaccine found effective in preventing HIV
Scientists have developed a vaccine which provides a strong immune response against HIV in mice, an advance that could lead to potent single-dose vaccines for a range of infectious diseases. The vaccine candidate, when delivered along with two powerful adjuvants that stimulate the immune system, could produce a wide diversity of antibodies against the HIV virus, according to a new study published in the journal Science Translational Medicine. Researchers from the Massachusetts Institute of Technology in the US found that the vaccine accumulated in the lymph nodes and remained there for up to a month, allowing mice to build up a much greater number of antibodies against the HIV protein. This strategy may lead to new vaccines that only need to be taken once for a range of infectious diseases, including HIV or Sars-CoV-2, scientists say. 'This approach is compatible with many protein-based vaccines, so it offers the opportunity to engineer new formulations for these types of vaccines across a wide range of different diseases, such as influenza, Sars-CoV-2, or other pandemic outbreaks,' said Christopher Love, a co-author of the study from MIT. Adjuvants are commonly given along with vaccines to help stimulate a stronger immune response against proteins present on pathogens. For instance, protein-based vaccines like those for hepatitis A and B are delivered along with the adjuvant aluminium hydroxide, also known as alum, which helps the body form a stronger memory of the infectious agent. Scientists previously developed another adjuvant called saponin derived from the bark of the Chilean soapbark tree. Researchers have shown that a tiny nanoparticle formulation of saponin, along with an inflammation-promoting molecule called MPLA, can be used as an adjuvant for an HIV vaccine under trial. An alum and SMNP combination used as an adjuvant for the vaccine could generate even more powerful immune responses against HIV or SARS-CoV-2, scientists say. Scientists suspect this combination boosts the immune response, specifically via the body's B cells, which produce antibodies. They found that such a vaccine combination accumulated in the mice lymph nodes, causing their B cells to undergo rapid mutations to generate a mix of antibodies against HIV. Researchers showed that the SMNP and alum combination helped an HIV protein penetrate through a protective layer of cells around the lymph nodes without being broken down. 'As a result, the B cells that are cycling in the lymph nodes are constantly being exposed to the antigen over that time period, and they get the chance to refine their solution to the antigen,' Dr Love explained. Scientists liken this process to what occurs during a natural infection, when antigens can remain in the lymph nodes for weeks, giving the body time to mount an immune response. 'What's potentially powerful about this approach is that you can achieve long-term exposures based on a combination of adjuvants that are already reasonably well-understood, so it doesn't require a different technology,' Dr Love said. 'It's just combining features of these adjuvants to enable low-dose or potentially even single-dose treatments,' he said.
South China Morning Post
08-05-2025
- Health
- South China Morning Post
Hong Kong scientists make breakthrough on needle-free flu jab offering more protection
Hong Kong scientists have made a breakthrough in developing a new flu vaccine that is needle-free and has the potential to induce a more robust immune response against various virus strains. Advertisement The University of Hong Kong's Li Ka Shing Faculty of Medicine said on Thursday it had developed two novel vaccine approaches, each with its own characteristics and advantages that were expected to be used to create a new flu jab in the future. Professor Leo Poon Lit-man, chair of public health virology, said the long-lasting protective effects of new vaccines may reduce the need to receive yearly jabs, with more research to be done to determine the exact frequency. 'On mice, the protection given by the vaccine was very satisfactory compared with other live-attenuated influenza vaccines and inactivated vaccines,' he said. 'We can also see that the mice had a great immune response against different types of influenza, including human and avian ones. We believe our vaccines are not required to be received every year.' Advertisement Live-attenuated vaccines use a weakened form of the virus that causes a disease. Because these vaccines are so similar to the natural infection that they help prevent, they create a strong and long-lasting immune response, according to health authorities.
