The present invention provides compositions and systems for delivery of nanocarriers to cells of the immune system. The invention provides synthetic nanocarriers capable of eliciting an immune system response in the form of antibody production, wherein the nanocarriers lack any T cell antigens. In some embodiments, the invention provides nanocarriers that comprise an immunofeature surface, which provides high avidity binding of the nanocarriers to antigen presenting cells. The invention provides pharmaceutical compositions comprising inventive nanocarriers. The present invention provides methods of designing, manufacturing, and using inventive nanocarriers and pharmaceutical compositions thereof.