Tag Archive for: antibody

Child using inhaler for asthma

Monoclonal antibody reduces asthma exacerbations in urban youth: Q&A with Stephen Teach, M.D.

Child using inhaler for asthmaNew research found that mepolizumab, a monoclonal antibody, decreased asthma flare-ups by 27% in Black and Hispanic children and adolescents who have a severe form of asthma, are prone to asthma attacks, and live in low-income urban neighborhoods.

Stephen Teach, M.D., principal investigator of the IMPACT DC asthma program and co-author of the NIAID-funded Inner City Asthma Consortium-conducted study, offers insight on the importance of this work and what it means for the future of pediatric asthma care at Children’s National Hospital.

What has been the hold-up in this field and how does this work move the field forward?

Urban, Black, and Hispanic children with asthma continue to suffer a disproportionate share of asthma-related morbidity. These findings show that innovative, phenotype-specific therapies are necessary to address their needs.

The study’s investigators were able to document a significant treatment effect in a particularly at-risk population and demonstrated specific gene pathways that were downregulated by treatment with mepolizumab.

What did you find that excites you about this work?

The exciting part of the Inner-City Asthma Consortium’s work has always been that it not only studies whether or not phenotype-driven interventions improve outcomes in high-risk kids, but how those interventions work from a fundamental mechanistic perspective. Those insights drive the science, and the potential clinical applications, forward in an iterative fashion.

How is Children’s National leading in this space?

Investigators from Children’s National continue to be national leaders in developing and testing innovative interventions to address the national disparities in pediatric asthma care and outcomes.

The study, published in the journal The Lancet was co-authored by William Sheehan, M.D., allergist.

The Division of Pulmonary Medicine at Children’s National has been ranked as one of the top ten programs in the nation by U.S. News & World Report.

antibodies attached to COVID

Study shows COVID-19 antibodies and virus can coexist

antibodies attached to COVID

Children’s National study shows that children can have COVID-19 antibodies and the virus in their system simultaneously.

With many questions remaining around how children spread COVID-19, Children’s National Hospital researchers set out to improve the understanding of how long it takes pediatric patients with the virus to clear it from their systems, and at what point they start to make antibodies that work against the coronavirus. The study, published Sept. 3 in the Journal of Pediatrics, finds that the virus and antibodies can coexist in young patients.

“With most viruses, when you start to detect antibodies, you won’t detect the virus anymore. But with COVID-19, we’re seeing both,” says Burak Bahar, M.D., lead author of the study and director of Laboratory Informatics at Children’s National. “This means children still have the potential to transmit the virus even if antibodies are detected.”

She adds that the next phase of research will be to test if the virus that is present alongside the antibodies can be transmitted to other people. It also remains unknown if antibodies correlate with immunity, and how long antibodies and potential protection from reinfection last.

The study also assessed the timing of viral clearance and immunologic response. It found the median time from viral positivity to negativity, when the virus can no longer be detected, was 25 days. The median time to seropositivity, or the presence of antibodies in the blood, was 18 days, while the median time to reach adequate levels of neutralizing antibodies was 36 days. Neutralizing antibodies are important in potentially protecting a person from re-infection of the same virus.

This study used a retrospective analysis of 6,369 children tested for SARS-CoV-2, the virus that causes COVID-19, and 215 patients who underwent antibody testing at Children’s National between March 13, 2020, and June 21, 2020. Out of the 215 patients, 33 had co-testing for both the virus and antibodies during their disease course. Nine of the 33 showed presence of antibodies in their blood while also later testing positive for the virus.

Also of note, researchers found patients 6 through 15 years old took a longer time to clear the virus (median of 32 days) compared to patients 16 through 22 years old (median of 18 days). Females in the 6-15 age group also took longer to clear the virus than males (median of 44 days for females compared to median of 25.5 days for males).

Although there is emerging data regarding this timing in adults with COVID-19, there is far less data when it comes to the pediatric population. The findings being gathered by Children’s National researchers and scientists around the world are critical to helping understand the unique impact on children and their role in viral transmission.

“The takeaway here is that we can’t let our guard down just because a child has antibodies or is no longer showing symptoms,” says Dr. Bahar. “The continued role of good hygiene and social distancing remains critical.”

Other researchers who contributed to this study include Cyril Jacquot, M.D.; Delores Y Mo,M.D.; Roberta L DeBiasi, M.D.; Joseph Campos, Ph.D.; and Meghan Delaney, D.O.

Adora Lin

Funding will help uncover immune system differences that trigger food allergies

Adora Lin

“When it comes to food allergies, we really don’t know how they develop. We don’t know how to best differentiate between a child who can safely eat a potential allergen, like peanuts, compared with a child who cannot safely eat peanuts.” says Adora A. Lin, M.D., Ph.D.

Adora A. Lin, M.D., Ph.D., an attending physician in Children’s department of Allergy and Immunology, was awarded $240,000 to improve understanding of how children’s immune systems tolerate or react to certain food allergens – sometimes triggering a cascade of side effects that can be fatal.

The three-year American Academy of Allergy, Asthma & Immunology (AAAAI) Foundation award will underwrite Dr. Lin’s ongoing research into the regulation of the antibody Immunoglobulin E (IgE), which plays a pivotal role in these allergic responses.

“Our immune system maintains a delicate balance, working just enough to ward off potential invaders and pathogens, but not so much that it triggers problems of its own making,” Dr. Lin says. “When it comes to food allergies, we really don’t know how they develop. We don’t know how to best differentiate between a child who can safely eat a potential allergen, like peanuts, compared with a child who cannot safely eat peanuts.”

Food allergies have become a growing problem and affect about 1 in 13 U.S. children, or about two per classroom. Food items such as eggs, milk, peanuts, tree nuts, soy and wheat trigger allergic reactions that can include itching, swelling, hives and difficulty breathing. As children’s immune systems react to exposure to such allergens, their B-cells produce IgE antibodies.

Apart from avoiding these foods and carrying rescue medications, which must be used immediately after accidental exposure, there is no way to treat food allergies effectively. That makes it essential to better understand how the immune system works in order to innovate new and better food allergy treatments and diagnostics.

Dr. Lin’s work involves isolating immune cells from blood samples, culturing them and stimulating an immune response to known food allergy triggers. B-cells make IgE, but additional clarity is needed about what turns on the “make IgE” signal as well as which signals indicate it’s time to stop making IgE. Ultimately, the aim is to identify biomarkers that are akin to the “check engine” light that illuminates to warn of a potential problem long before a car stalls in traffic.

“I’m very excited about this funding,” Dr. Lin adds. “Our field has done an exceptional job with clinical work to help children with food allergies. This award recognizes the importance of the mechanistic side of the equation. I’m excited to help make that contribution to the research.”

As it stands now, blood tests are sensitive to food-related IgE, but are not specific. Only 30 to 55 percent of children who have IgE to common food allergens have an allergic reaction after eating the food, which means that 45 to 70 percent are merely sensitized and could tolerate eating the food. Current tests cannot distinguish between sensitized and allergic children.

“Our hope is to identify biomarkers that would serve as the ‘check engine’ light that tell us in advance which child’s immune system will react strongly to that food. Right now, there is no way to tell. This project will help uncover those differences,” she says.

Dr. Lin was one of three recipients of the AAAAI Foundation’s faculty development award, which was presented during a March 3, 2018, award ceremony held during the organization’s business meeting.