The monoclonal antibody (F 10-44-2) described in this report recognizes an antigen which by quantitative absorption analysis is found predominantly on spleen, lymph node, bone marrow, thymus, granulocytes and brain, the amount of antigen on these tissues being approximately the same within a factor of 2 or 3. Analysis with the fluorescence-activated cell sorter showed that 29% of thymus cells, 61% of bone marrow cells, 95% of blood mononuclear cells, 98% of lymph node lymphocytes and 100% of granulocytes carried the antigen. With blood mononuclear cells and lymph node lymphocytes, there were two distinct peaks, with one peak labeling very weakly. Double labeling experiments established that the weakly labeled peak contained the B lymphocytes. Studies on frozen sections of thymus established that positive thymocytes were found only in the medulla indicating that the antigen appears late in T lymphocyte maturation. The lymphatic nodules (B lymphocyte areas) of spleen and lymph node appeared virtually negative on frozen sections showing that there was too little antigen on the B lymphocyte surface for confident detection by fluorescence microscopy. Sodium dodecyl sulfate polyacrylamide gel eletrophoresis of NaB3H4-labeled blood mononuclear cells established that the antigen was a major glycoprotein of the leukocyte membrane and that its mol. wt. was 105000. This antigen shows a striking similarity in biochemistry and tissue distribution to the W 3/13 antigen of the rat and is likely to be the human homologue of this antigen.

The monoclonal antibody (F 10-89-4) described in this study recognizes an antigen which by quantitative absorption analysis is absent from human brain, kidney, liver, heart, erythrocytes, platelets and normal serum, but is present on spleen, lymph node, chronic lymphatic leukemia cells, bone marrow, thymus and granulocytes at a ratio of 1:1:0.8:0.3:0.1, respectively. Analysis with the fluorescence-activated cell sorter showed that 100% of thymocytes, lymph node lymphocytes, blood mononuclear cells and granulocytes carry the antigen, while 83% of bone marrow cells are positive. There was marked heterogeneity in the amount of labeling of thymocytes, with 3 major peaks. There was also heterogeneity of labeling of blood mononuclear cells and lymph node lymphocytes, with a weakly staining hump containing approximately 20% of the cells in the case of lymph node lymphocytes. Double labeling experiments demonstrated that the weakly staining cells of blood and lymph node were B lymphocytes, while frozen sections of thymus showed that the antigen was expressed most weakly in subcapsular cortical thymocytes, and most strongly on medullary thymocytes. Biochemical studies established that the antigen bound to lentil lectin columns, and sodium dodecyl sulfate polyacrylamide gel electrophoresis studies using NaB3H4-labeled blood mononuclear cells established that the antigen was a major glycoprotein of lymphocytes, and that its molecular weight was in the region of 190000 to 215000.

ROYAL VICTORIA INPIRMARY, NEWCASTLE UPON TYNEISOLATED liver perfusion has been used for the study of liver physiology (Brauer, Pessotti, and Pizzolato, 195 I ; Martinis, Goldsworthy, Jones, Nyhus, DeVito, Volwiler, and Harkins, 1958; Vang and Drapanas, 1965). The technique has also been used for the treatment of patients in hepatic coma (Eiseman, Liem, and Raficci, 1965;Norman, Brown, Saravis, Ackroyd, and McDermott, 1966; Abouna, KirMey, Hull, Ashcroft, and Kerr (1969) and as a method of liver preservation prior to its transplantation (Kestens, 1965;Brettschneider and Starzl, 1967).In all these situations proper assessment of liver viability is essential and it is generally agreed that the rates of oxygen consumption and bile production are two simple but reliable guides. However, because of the multiplicity and complexity of liver cell functions, a more extensive assessment is usually desirable, and a large variety of liver-function tests have been used for this purpose. These include the clearance of bromsulphalein (B.S.P.) (Chapman, Goldsworthy, Nyhus, Volwiler, and Harkins, 1960), the clearance of ammonia (Eiseman, Knipe, Koh, Normell, and Spencer, 1963), and the clearance of lactate and pyruvate (Schimassek, 1965); the rate of synthesis of glycogen from glucose (Craig, 1966); the synthesis of urea from ammonia (Hems, Ross, Berry, and Krebs, 1966); the rate of elimination of galactose (Tengstrom, 1966); the rate of glucose oxidation (Sicular and Moore, 1961); and the rate of uptake of potassium (Flink, Hastings, and Lowry, 1950).Unfortunately, conflicting views are held with regard to the value of some of these tests. Drapanas, Zemel, and Vang (1966) have stated that the clearance of ammonia, B.S.P., and bilirubin can be carried out readily by even the dying liver, whereas Van Wyk and Eiseman (1966) have used these same liverfunction tests as criteria of liver viability.We first developed a successful technique for the prolonged perfusion of an isolated pig liver. This technique was then used in a series of twelve perfusions in order to assess the value and limitations of some of the above liver-function tests and to study the changes in liver viability during perfusion as a function of time. MATERIALS AND METHODSThe animals used were large white pigs weighing 60-80 lb. All animals were fed on glucose and vitamin-E supplements for 36 hours before operation. The pigs were anaesthetized with halothane, nitrous oxide, and oxygen, via a tracheostomy. The external jugular vein and the carotid artery were cannulated for administering intravenous glucose * Read at a meeting of the Surgical Research Society, January, 1968. 21and for monitoring the blood-pressure respectively. The liver was exposed through a transverse upper abdominal incision, since with this approach the bowel remains within the peritoneal cavity and hence minimizes hypovolaemic shock. The liver was mobilized with the minimum of trauma. During hepatectomy the animal was given heparin (4 mg. per kg.), intravenous dextrose solution, and sodium...