Junction between Kupffer Cells and Hepatic Sinusoidal Endothelium. A Review

In this review, the junctions between Kupffer and sinusoidal endothelial cells previously revealed by the present authors under the transmission electron microscope in both normal human and bat livers has been discussed and compared with stereoimages of the connections between the two cell types reported by other authors in scanning electron microscopic studies. It is concluded that Kupffer cells lie on the gap or opening of the endothelial lining of the sinusoid, that part of the perisinusoidal surface of the cell body which is applied to the opening directly faces the perisinusoidal space, and that the margin of this part of the perisinusoidal surface of the Kupffer cell and the margin of the endothelial opening are circularly bound by means of a peculiar close junctional area identical in structure and appearance with the so-called "junctional complex" (Wisse) between endothelial cells. The two junctional areas between the Kupffer cell and the endothelial sheet which are found in a pair in transmission electron microscopic preparations on two diametrical parts of the perisinusoidal surface of the Kupffer cell, should be derived from the perpendicular section of such a circular margin of the endothelial opening attached to the Kupffer cell body. Thus, the integrity of the lining of the sinusoid is maintained and Kupffer cells are immovably fixed to the sinusoidal lining resisting the drag induced by the blood flow in the sinusoid.