Latest news with #allergens
Medscape
2 days ago
- Health
- Medscape
T Cells Target Cockroach Allergens in Therapy Extracts
Cockroach immunotherapy effectively modulates T-cell responses in asthmatic children, found authors of a small randomized trial in The Journal of Allergy and Clinical Immunology. They found that immunodominant allergens are preferentially targeted and trigger the strongest modulation regardless of their concentration in treatment extracts. Alessandro Sette, DrBiolSci 'In general, immunotherapy works to ameliorate allergic disease, but the mechanisms that afford its efficacy are not well understood,' corresponding author Alessandro Sette, DrBiolSci, of the Center for Vaccine Innovation at the La Jolla Institute for Immunology, La Jolla, California, told Medscape Medical News. It is unknown whether T-cell responses to immunodominant allergens are more or less sensitive to modulation and whether the allergen abundance in the immunotherapy extract influences T-cell modulation, the authors noted. To fill these knowledge gaps, Sette and colleagues evaluated CD4+ T-cell reactivity to cockroach allergens in the double-blinded, placebo-controlled, multicenter CRITICAL (Cockroach Immunotherapy in Children and Adolescents) trial of SCIT (subcutaneous allergen immunotherapy). Sette added that like rodents, cockroaches produce important allergens, particularly in under-resourced urban settings. Strongly associated with asthma onset, progression, severity, and morbidity, cockroach allergy — particularly to the German cockroach ( Blattella germanica ) — is a significant global health concern. It affects children and young adults disproportionately, with cockroach allergens detected in 85% of low-income inner-city homes in the U S. While several studies have identified cockroach allergens based on immunoglobulin E reactivity and correlated sensitization with symptom severity, T-cell responses have been less thoroughly characterized, Sette said. T-cell responses, particularly in those sensitized to cockroach allergens, are typically associated with type 2 T-helper cells (Th2), which play a central role in allergy and asthma, he said. The study found that down-regulation of Th2 response did not correlate with the abundance of the various allergens in the extract. 'This is important because it suggests that variation in extract content should not impact the downregulation of the detrimental Th2 responses,' Sette said. 'Responses from patients who were highly reactive were downregulated about as well as those from less reactive patients, suggesting that patients can benefit regardless of the strength of their allergic responses.' The findings align with immunotherapy studies of other allergens, he noted. The results suggest room for a more nuanced approach to cockroach SCIT, incorporating allergen immunodominance, individual patient responses, and abundance-based standardization, which has proven successful for other allergens, said Sette. Study Details The results emerged from an evaluation of CD4+ T-cell reactivity specific to the main cockroach allergens in the study extract. During 2018-2022, young participants, aged 8-17, with mild-to-moderate, well-controlled asthma were recruited from 11 sites in urban and under-resourced neighborhoods in Baltimore; Boston; Chicago; Dallas; Denver; Detroit; New York City; Washington, DC; Cincinnati; and St. Louis. All had positive skin and nasal tests to cockroach allergy. The children were randomized to receive 12 months of cockroach SCIT injection in 26-step dose escalation (n = 20) or placebo (n = 26). Peripheral blood mononuclear cells were isolated at baseline and after 12 months of treatment or placebo. T-cell responses were evaluated for magnitude, cytokine polarization (differentiation), allergen immunodominance, and correlation with allergen content in the cockroach SCIT extract derived from 11 well-defined cockroach allergens. SCIT modulation was more prominent in participants with the strongest and greatest number of Th2 polarized responses, the study found. Downmodulation was observed against Bla g 5 and Bla g 9, the most dominantly recognized cockroach allergens for the study population. Furthermore, effective modulation was observed independently of the amount of allergen content in the SCIT extract. Moreover, treatment responsiveness was strongly predicted by baseline immune characteristics, with SCIT modulation more prominent in children with the strongest and most polarized Th2 responses. 'Individual variability in allergen recognition patterns may explain different treatment outcomes,' Sette said. Marie Cavuoto Petrizzo, MD, MSEd Offering a nonparticipant's perspective on the study, Allergist/Immunologist Marie Cavuoto Petrizzo, MD, MSEd, associate dean for medical education at the Zucker School of Medicine at Hofstra University in Hempstead, New York, noted that SCIT currently utilizes crude allergen extracts that are not strictly standardized and are highly variable in content. 'Consistent with previous literature, in this study SCIT resulted in modulation of T cells — that is, measurable changes in T-cell quantity and quality — and a shift from Th2 response to allergens to a Th1 response,' she told Medscape Medical News. 'What is novel is the determination that the most significant downmodulation occurred against Bla g 5 and Bla g 9 allergens, which are more frequently recognized by T cells. These allergens are immunodominant but in low abundance in the extracts used during SCIT.' Since immunodominance varies between individuals, Cavuoto Petrizzo added, 'by identifying immunodominant allergens as key targets for modulation, even at low concentrations, it may be possible to develop more effective immunotherapies that prioritize these components. This targeted approach could lead to improved treatment outcomes in cockroach-allergic asthmatic patients.' And while this study focused on cockroach allergy, the findings may have implications for other allergens as well, she said.
The Independent
3 days ago
- Health
- The Independent
No city is safe for allergy sufferers, study finds
There's no escape from it — pollen is in every U.S. state, ready to torment your nostrils. The seeds rain down from the trees in a strange yellow haze and ascends to the skies from the flowers and grasses. Even if you could easily pack up and move, nowhere is safe to avoid the dreaded, sniffling effects of seasonal allergies. 'It's a little bit like playing Russian Roulette,' Hannah Jaffee, the director of research at the Asthma and Allergy Foundation of America, told The Independent. 'If you already have allergies, you can be exposed to an entirely different set of allergens if you relocate.' 'Worst case scenario: you may live in a place and either not have allergy symptoms or have mild allergy symptoms. Then, you move somewhere else and start developing significant symptoms,' she added. Everyone is going to respond differently to a new location. 'If you already have allergies, you can be exposed to an entirely different set of allergens if you relocate. So, you might be trading some symptoms for others.' 'And then, in some cases, your symptoms might improve by relocating,' Jaffee said. More than 100 million Americans live with various types of allergies and over 81 million have seasonal pollen allergies. Some are genetically predisposed to develop allergies, which can factor into what they're allergic to and potentially how severe their symptoms would be. Many people develop allergies as they age and their immune system weakens. Seasonal allergies, which are also commonly known as 'allergic rhinitis' or hay fever, occur when people are exposed to pollen. The inflammatory response can cause sneezing, congestion, a runny nose, or red, watery, and itchy eyes. For people with asthma, it can lead to an asthma attack. For tens of thousands of people, it may even result in a trip to the emergency room. The severity of allergy symptoms also depends on where you live. There are three main types of pollen, including tree, grass, and weed. This year, the highest tree pollen levels were forecast across a wide swath stretching from the Pacific Northwest to the Southeast. The highest weed pollen levels were expected around the Plains states, the Carolinas, and along the Gulf Coast. The foundation also released what it named the nation's top 10 cities for seasonal allergies, with most located in the South and Southeast. Historically, the worst cities are in those regions, Jaffee noted. 'That's because these are climates that tend to be more humid and warmer, so they kind of favor that growth of pollen and mold,' she explained. Wichita, Kansas, led the rankings as the worst city for allergy sufferers. 'Since allergies are so different for everyone, you can thrive in the Southeast part of the U.S. and not have any allergies or still experience significant allergy symptoms elsewhere,' Jaffee said. 'It's kind of a mixed bag.' So, what do you do if you are moving — or want to? Generally, experts recommend that you visit the location for about two to four weeks ahead of time to get a sense of how your body responds, or to visit during different seasons. Talking to an allergist will also be useful for more personalized recommendations. Still, pollen seasons are getting longer and stronger for everyone. Human-caused climate change is resulting in earlier seasons, as well, with warmer temperature trapping heat around urban areas, increasing air pollution, and stimulating pollen production. The amount of pollen released by trees is higher and the strength of the allergic response to the tree pollen appears to be stronger. 'There's no question [that] as there's global warming, the pollen season is increasing,' Dr, Sanjiv Sur, director and professor of Allergy and Immunology at Baylor College of Medicine, said earlier this year. What may help ease the pain, if only for right now? Dr. Neelu Tummala, a clinical assistant professor of otolaryngology at NYU Langone Health, advises that people time taking medications so they are optimally effective, change clothes and take off shoes after spending time outside, and bathe pets. Jaffee recommends a pollen tracking app, in addition to personalized allergy testing. But, ultimately, there needs to be a wider response. 'Long-term, we should be looking at policy change to reduce the impact of climate change,' said the foundation's chief mission officer Melanie Carver.
South China Morning Post
4 days ago
- Health
- South China Morning Post
Love king crab but worried about allergies? Hong Kong researchers have solution
King crab is a favourite of Hong Kong seafood lovers, as long as they do not have a reaction to the delicacy, which was among six types of shellfish found to contain eight newly identified allergens. Advertisement A study led by Chinese University of Hong Kong academics looked at six types of crabs popular with local diners and found 11 allergens, including eight identified for the first time. Revealing their findings, the researchers said that a more precise diagnosis would allow patients to consume crabs to which they were not allergic. 'Crabs are one of the most important types of shellfish that cause allergic reactions,' said Leung Ting-fan, a paediatrics professor at the university. Crabs are the second largest cause of food allergy among Hong Kong pupils aged six to 11 after shrimp, affecting around 0.2 per cent of them, according to research published in 2020. Advertisement Crabs are a delicacy in Hong Kong, especially the most expensive king crabs, which can cost at least HK$1,800 for one weighing 2.5kg. The best season for king crabs is considered winter, with ones sourced from the cold waters of Alaska, Russia and Hokkaido in Japan highly prized.
The Independent
5 days ago
- Health
- The Independent
Wanna get away? Sorry, there's no destination safe from seasonal allergies
There's no escape from it — pollen is in every U.S. state, ready to torment your nostrils. The seeds rain down from the trees in a strange yellow haze and ascends to the skies from the flowers and grasses. Even if you could easily pack up and move, nowhere is safe to avoid the dreaded, sniffling effects of seasonal allergies. 'It's a little bit like playing Russian Roulette,' Hannah Jaffee, the director of research at the Asthma and Allergy Foundation of America, told The Independent. 'If you already have allergies, you can be exposed to an entirely different set of allergens if you relocate.' 'Worst case scenario: you may live in a place and either not have allergy symptoms or have mild allergy symptoms. Then, you move somewhere else and start developing significant symptoms,' she added. Everyone is going to respond differently to a new location. 'If you already have allergies, you can be exposed to an entirely different set of allergens if you relocate. So, you might be trading some symptoms for others.' 'And then, in some cases, your symptoms might improve by relocating,' Jaffee said. More than 100 million Americans live with various types of allergies and over 81 million have seasonal pollen allergies. Some are genetically predisposed to develop allergies, which can factor into what they're allergic to and potentially how severe their symptoms would be. Many people develop allergies as they age and their immune system weakens. Seasonal allergies, which are also commonly known as 'allergic rhinitis' or hay fever, occur when people are exposed to pollen. The inflammatory response can cause sneezing, congestion, a runny nose, or red, watery, and itchy eyes. For people with asthma, it can lead to an asthma attack. For tens of thousands of people, it may even result in a trip to the emergency room. The severity of allergy symptoms also depends on where you live. There are three main types of pollen, including tree, grass, and weed. This year, the highest tree pollen levels were forecast across a wide swath stretching from the Pacific Northwest to the Southeast. The highest weed pollen levels were expected around the Plains states, the Carolinas, and along the Gulf Coast. The foundation also released what it named the nation's top 10 cities for seasonal allergies, with most located in the South and Southeast. Historically, the worst cities are in those regions, Jaffee noted. 'That's because these are climates that tend to be more humid and warmer, so they kind of favor that growth of pollen and mold,' she explained. Wichita, Kansas, led the rankings as the worst city for allergy sufferers. 'Since allergies are so different for everyone, you can thrive in the Southeast part of the U.S. and not have any allergies or still experience significant allergy symptoms elsewhere,' Jaffee said. 'It's kind of a mixed bag.' So, what do you do if you are moving — or want to? Generally, experts recommend that you visit the location for about two to four weeks ahead of time to get a sense of how your body responds, or to visit during different seasons. Talking to an allergist will also be useful for more personalized recommendations. Still, pollen seasons are getting longer and stronger for everyone. Human-caused climate change is resulting in earlier seasons, as well, with warmer temperature trapping heat around urban areas, increasing air pollution, and stimulating pollen production. The amount of pollen released by trees is higher and the strength of the allergic response to the tree pollen appears to be stronger. 'There's no question [that] as there's global warming, the pollen season is increasing,' Dr, Sanjiv Sur, director and professor of Allergy and Immunology at Baylor College of Medicine, said earlier this year. What may help ease the pain, if only for right now? Dr. Neelu Tummala, a clinical assistant professor of otolaryngology at NYU Langone Health, advises that people time taking medications so they are optimally effective, change clothes and take off shoes after spending time outside, and bathe pets. Jaffee recommends a pollen tracking app, in addition to personalized allergy testing. But, ultimately, there needs to be a wider response. 'Long-term, we should be looking at policy change to reduce the impact of climate change,' said the foundation's chief mission officer Melanie Carver.
CNA
24-07-2025
- Health
- CNA
CNA938 Rewind - Eat, Drink, Singapore - Celebrating SG60 at Edge
CNA938 Rewind - Why the need for an Asia-specific allergic rhinitis database Singapore is developing Asia's first allergic rhinitis database. The condition – commonly known as hay fever – is triggered by allergens such as dust, pollen and pet dander. Andrea Heng and Hairianto Dimand speak with Koh Tze Sin, a 26 year-old Singaporean living with Allergic Rhinitis for hear a first hand account. They also speak with Adjunct Associate Professor Ng Chew Lip, Senior Consultant, Department of Otolaryngology - Head & Neck Surgery (ENT) and the principal investigator of Project ENTenna to find out more about the study.
