- Detection of virulent Shigella and enteroinvasive Escherichia coli by induction of the 43 kDa invasion plasmid antigen, ipaC. Shamlal, R., Rajarathnam, S., Sankaran, K., Ramachandran, V., Subrahmanyam, Y.V., Nair, G.B., Macaden, R., Roy, R.K. FEMS Immunol. Med. Microbiol. (1997)