Protection from malaria infection conferred by RTS,S has been linked to antibodies specific for a central repeat domain of the malaria circumsporozoite protein (CSP). The cellular immune responses that drive the production of these protective antibodies are not yet fully understood. Researchers at the University of Miami are working to characterize cellular responses following immunization with RTS,S/AS01B, particularly those related to a subset of T cells known as T follicular helper cells (Tfh), and their interactions with antibody-producing B cells. If any specific characteristics of these responses are shown to be linked to vaccine responsiveness or efficacy, they may be utilized as surrogate markers of immunity or protection from malaria in future clinical trials.