AUGMENTED EXPRESSION AND RELEASE OF NONSPECIFIC CROSS-REACTING ANTIGENS (NCAS), MEMBERS OF THE CEA FAMILY, BY HUMAN NEUTROPHILS DURING CELL ACTIVATION

Nonspecific cross-reacting antigens (NCAs) are a group of human glycoproteins immunologically cross-reactive with carcinoembryonic antigen (CEA). Our previous studies have shown that at least seven NCA glycoproteins different in molecular weight and antigenic reactivity, including a species corresponding to CD67, can be detected in neutrophil granulocytes. In the present paper, it is demonstrated that neutrophil activation induced with soluble stimulators, the calcium ionophore A23187, N-formylmethionyl-leucyl-phenylalanine, and phorbol myristate acetate, results in augmented release and cell surface expression of NCAs. The NCA release was correlated with the discharge of azurophil granules but not with that of specific granules and was attributable to the release of NCA species of 53 and 30 kd. The increased NCA expression on the cell surface was due to increments of the NCAs of 160, 100 (CD67), 95, 90, 30, and 26 kd. These results, together with the previous findings that the CEA family members can mediate intercellular adhesion and bind Escherichia coli in vitro, imply that the neutrophil NCAs participate in the functions of neutrophils such as phagocytosis, chemotaxis, and adherence.