Surface presentation of antigens protein (SPAN), also know as invasion protein invJ, is a Salmonella secretory pathway protein involved in presentation of determinants required for mammalian host cell invasion.

1: Functional analysis of the Salmonella typhimurium invasion genes invl and invJ and identification of a target of the protein secretion apparatus encoded in the inv locus. Collazo CM, Zierler MK, Galan JE; Mol Microbiol 1995;15:25-38. PMID:7752894