Tracking Down Allergy-Causing T Helper Cells (video) American Association for the Advancement of Science Share Print E-Mail Loading video... Caption Scientists finally tracked down the specific population of T cells that cause problems in allergies. T helper cells protect against pathogens, but a newly-identified subgroup dubbed TH2A are responsible for causing allergic symptoms, and can be distinguished from their protective counterparts by specific markers. Credit [Credit: Carla Schaffer / E. Wambre et al. / AAAS] Usage Restrictions Please cite the owner of the material when publishing. This material may be freely used by reporters as part of news coverage, with proper attribution. Non-reporters must contact Science for permission. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.