Fig. 1.

(A) CEACAM16 amino acid sequence and structural domains. Yellow indicates IgV-like domains; green indicates IgC-like domains. Predicted N-glycosylation sites are in red. Asterisks indicate cysteines; arrow shows the proteolytic cleavage site. Amino acids used to generate anti-CEACAM16 are underlined. (B) CEACAM16 forms oligomers in the cell pellet and is degraded by subtilisin. (C) CEACAM16 oligomers also are found in the cell-culture medium collected from Ceacam16-transfected HEK293T cells (CEACAM16) but not from untransfected cells (control). DTT reduces CEACAM16 oligomers to monomers.