The present invention provides methods and compositions for the stimulation of immune responses. In particular, the present invention provides immunogenic nanoemulsion compositions and methods of using the same for the induction of immune responses (e.g., innate and/or adaptive immune responses (e.g., for generation of host immunity against a bacterial species of the genus Streptococcus (e.g., Streptococcus pneumoniae))). Compositions and methods of the present invention find use in, among other things, clinical (e.g. therapeutic and preventative medicine (e.g., vaccination)) and research applications.