sem experiments have shown that : ( i ) nk cells are large and possess various shapes in contrast to the yac target cells which are smaller and round , ( ii ) yac cells have uniformly distributed microvilli whereas the nk cell microvilli are most prominent in the area of effector-to-target contact , and ( iii ) in the absence of target cells , nk cell microvilli are found in a small number ( usually 1-3 ) of cell surface locations .
C0007634
cells
C0026049
microvilli