Cecilia Chen
Pronouns: She/Her
Research Mentor(s): Jessica O’Konek
Research Mentor School/College/Department: Mary H Weiser Food Allergy Center / Medicine
Program: UROPF
Session: Session 3 (11:00am – 11:50am)
Authors:
Abstract
A large percentage of vaccines are given in early life. Vaccines are shown to be safe and effective, however, few studies have dived into the specific immune responses in neonates. Vaccines can induce different types of immune responses depending on many factors, including the individual as well as immunostimulatory substances added to vaccines called adjuvants. Two types of cellular immune responses that are often characterized are Th1 or Th2. Our team is looking to see if there is anything in early life that changes the responses to adjuvanted vaccines in comparison with the same vaccine given to adults. To approach this question, we conduct vaccination with Hepatitis B surface antigen (HBsAg) and alum adjuvant, as this vaccine is often given to neonates. We compared responses in mice that are 7 (neonates), 21 (infants), or 56 days old (adults). Enzyme-linked immunosorbent assays (ELISA) were performed to measure the antibody content in the blood as well as harvesting lymphocytes from the spleen and lymph nodes and restimulated them with HBsAg to quantify antigen-specific cytokine production. Our results demonstrate a different response to the HBsAg vaccine in neonates compared to adult mice. Neonatal mice have a much more Th2-skewed response to the vaccine, with a complete lack of Th1 cytokines. The immune response to the vaccine in adults is more balanced, and both Th1 and Th2 immune responses are induced. Therefore, It is proven that there is an association between the age at vaccination and the type of immune response that is induced. Future directions include the investigation of whether vaccination in neonates impacts trained innate immunity, which raises the broader question of whether vaccines, like exposures to pathogens, shape immune development.
