American and Puerto Rican scientists have developed a nasal swab test for children that can diagnose a specific subtype of this respiratory disease.
- T helper 2 (T2) cells and T helper 17 (T17) cells are subtypes of CD4 T lymphocytes involved in asthma.
- A nasal swab test for children with asthma detected three transcriptomic profiles corresponding to the T helper 2 (T2)-high, T helper 17 (T17)-high, and T2-low/T17-low asthma endotypes.
- This rapid asthma endotype detection test could pave the way for more personalized treatments.
Widespread among children, asthma varies depending on endotypes. As a reminder, this respiratory pathology has been classified into endotypes known as T2-high or T2-low depending on the amount of T helper 2 inflammation present. “More recently, T2-low has been divided into two endotypes: T17-high, which has less T helper 2 inflammation and more T helper 17 inflammation, and T17-low, which has low levels of both of these. types of inflammation”, according to researchers from the universities of Pittsburgh (United States) and Puerto Rico.
459 young asthmatics used the nasal swab test
In order to diagnose these endotypes, which are driven by different immune cells and respond differently to treatments, it is necessary to carry out a genetic analysis of a sample of lung tissue taken during a procedure, called bronchoscopy, which takes place under general anesthesia . Problem: it cannot be performed in children. Thus, health professionals must rely on imprecise tools, including immune markers in the blood, lung function and whether or not young people suffer from allergies.
To overcome the problem, American and Puerto Rican scientists decided to develop a nasal swab test to characterize asthma endotypes based on cell types. To test the effectiveness of the device, the team carried out a study during which nasal samples from 459 young asthmatics, aged 6 to 20, were collected. Next, she analyzed the expression of eight T2 and T17 signature genes. “Clinical features, total and allergen-specific immunoglobulin E (IgE), blood eosinophils and lung function were compared across nasal epithelial transcription profiles,” the authors clarified.
Asthma: 3 exclusive profiles corresponding to endotypes have been identified
According to the results, published in the journal JAMAanalysis of the nasal swab samples revealed the patient’s endotype. In detail, 23% to 29% of participants presented a high T2 endotype, 35% to 47% a high T17 endotype and 30% to 38% a low endotype. “The median of total IgE and blood eosinophils for the T2-high profile was higher than for the T2-low profiles. Among volunteers in all profiles, at least 50% had at least one positive allergen-specific IgE “, can we read in the works.
Researchers say this non-invasive approach could help healthcare professionals prescribe medications more accurately and pave the way for finding better treatments for less-studied types of asthma, which have been difficult to accurately diagnose until ‘now.