On the cell biology of pit cells, the liver-specific NK cells

Table 1 Characteristics of LD, HD pit cells and peripheral blood NK cells

Item	LD pit cell	HD pit cell	Blood NK cell
Morphology*
Size(μm2)	27.7	24.5	24.8
Rod-cored vesicles per cell	1.0	0.8	0.5
Microvilli per cell	5.2	5.9	7.1
Size of granules (μm2)	Smaller(0.09)	Intermediate(0.1)	Larger(0.14)
Number of granules per cell	Higher(50)	Intermediate(20)	Lower(1 0)
Surface antigens+
CD2	80	80	80
CD8	100	100	40
CD11a	90	90	54
CD18	90	90	90
CD54	35	35	35
Asialo-GM1	36	70	100
NKR-P1	95	95	94
Functional features
NK activity	High	Intermediate	Low
P815 cell killing	Yes	No	No

^*Data from reference 19.

⁺Approximate % of cells that express antigen; data summarized from referen ces 2, 13, 16, 19, 25, and 32.