Normal mouse spleen cells express low levels of lymphocyte function‐associated anti‐gen‐1 (LFA‐1) as well as other lymphoid cells. However, fractionation of spleen cells with Percoll discontinuous gradients resulted in the appearance of lymphocytes expressing high levels of LFA‐1 molecule (LFA‐1 high lymphocytes) in parallel with the enrichment of natural killer (NK) activity. Lower density spleen cells (fractions 1 and 2) expressed higher level of LFA‐1 antigen than unfractionated spleen cells and showed a higher NK activity. In contrast, higher density spleen cells (fractions 3 and 4) expressed lower levels of LFA‐1 antigen and revealed lower NK activity. LFA‐1 high lymphocytes possessed a high level of asialo GM1, which was the cell surface marker for NK cells. Moreover, sorting of LFA‐1 high lymphocytes from spleen cells caused a great enrichment of NK cells. These results demonstrated that in vivo NK cells expressed higher levels of LFA‐1 molecule, which was an important adhesion molecule for NK cell‐mediated cytotoxicity.
ASJC Scopus subject areas
- Immunology and Allergy