Sialyl SSEA-1 Antigen as a Carbohydrate Marker of Human Natural Killer Cells and Immature Lymphoid Celis

• Published in: Blood Vol. 74; no. 1; pp. 255 - 261
• Main Authors: Ohmori, Katsuyuki, Yoneda, Tomoya, Ishihara, Goshi, Shigeta, Katsuyoshi, Hirashima, Kunimi, Kanai, Mutsuyuki, Itai, Shigeyuki, Sasaoki, Tetsu, Arii, Shigeki, Arita, Hiroshi, Kannagi, Reiji
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.07.1989
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V74.1.255.255

The distribution of a carbohydrate antigen, the sialyl SSEA-1 (sialyl Lex-i), in human lymphoid cells was investigated by flow cytometry with a specific monoclonal antibody, MoAb FH-6. We concluded that the lymphocytes positive for the sialyl SSEA-1 antigen present in normal peripheral blood (PB) are natural killer (NK) cells since the positive cells had an NK activity toward K562 cells, and most of the sialyl SSEA-1+ cells were simultaneously positive for Leu-11 (CD-16) and Leu-19. Essentially, no T and B cells, defined by Leu-4 (CD3) and Leu-16 (CD20), were positive for the sialyl SSEA-1 antigen in PB samples taken from healthy donors and patients with disorders unrelated to lymphoid malignancies. Among the malignant lymphoid cells, many sialylated SSEA-1 + cells were observed in large granular lymphocyte (LGL) leukemia cells and some acute lymphoblastic leukemia (ALL) blasts, but not in CLL cells or malignant lymphoma cells. Sialyl SSEA-1 was also positive in some cultured human lymphoid cell lines. We conclude that expression of the sialyl SSEA-1 antigen is strictly limited to a distinct population of NK cells among the mature lymphocytes in normal PB, but the antigen is present in a wide range of immature lymphoblasts of T- and B-cell lineages as well as the NK-cell lineage. The sialyl SSEA-1 antigen disappears from the surface of immature lymphocytes of T- and B-cell lineages during the course of maturation.