CEACAM5 and neoplasm: Two years later, Conry et al. [8] published that ivt mRNA coding Carcino Embryonic Antigen (CEA) and injected naked (just in saline, without any cationic carrier or liposome) in the muscle can prime an antibody response against CEA that becomes evident after challenge of the mice with CEA-expressing tumor cells (injections were twice weekly for five weeks with 50 μg of ivt RNA encoding CEA), i.e., a total amount of 500 μg of mRNA per mouse.