1181 all causes in the ward, 31% (11/35) of deaths from chronic bronchitis, and 78% (7/9) of deaths from pulmonary tuberculosis.
Lodging-houses attract people already in poor health and a mortality higher than in the general population might thus be A small area can have a great influence on the mormuch larger area and this "common lodging-house effect" may be a feature of public-health statistics in inner city
expected.
tality of a areas.
Department of Physics, Westminster Hospital,
London SW1
Liverpool
Area Health
Authority
R. F. MOULD K. WRIGHTON D. S. PICKUP
ESCHERICHIA COLI RECEPTORS ON HUMAN KIDNEY BRUSH-BORDER MEMBRANES
SIR,-We read with interest your editorial on Bacterial Adhesiveness and the Gut.’ Since attachment of bacteria might be one essential feature in the pathogenesis of infectious diseases, elucidation of interactions of bacterial antigens and constituents of the epithelial plasma membrane surface is of considerable interest. We have been studying brush-border membranes isolated from human kidney cortex.2,3 In an attempt to detect adherence of bacterial constituents to biomembranes, a property which may be relevant to the pathogenesis of some kidney diseases, we incubated kidney brush-border membranes with purified 0 and K antigens of Escherichia coli (013, 068, Kll, K64) for 4 h at 370C then overnight at 4°C.’ After extensive washing the plasma membranes were solubilised by papain, bromelains (protein/enzyme ratio 20/1, w/w), 3 mol/1 potassium chloride, ’Triton X100’ (0.01-1 %), and sodium desoxycholate (D.O.C., 0.2-1.2%). After centrifugation (1 h, 60 000 g) 0 and K antigens and soluble brush-border constituents were looked for by double immunodiffusion with antisera directed against bacterial 0 and K antigens and brush-border membranes.2-4 While none of the E. coli antigens studied could be detected in the supernatants of the controls, treatment with potassium chloride and especially papain, triton X100, and D.O.C. caused release of bacterial 0 and K components, thus indicating previous attachment to the plasma membranes. Soluble brush-border antigens were found in supernatants after digestion with papain (bromelains) and after treatment with detergents but not after potassium chloride. Negative staining of the untreated brush-border membrane surface showed numerous globular particles of 5 nm diameter bound to a 7-8 nm linear constituent sticking to the membrane matrix.s These nodules could be selectively removed after limited proteolysis (15 min); however, incubation with hypotonic solution (distilled water) and potassium chloride was not effective while detergents (triton, D.O.C.) caused solubilisation of globular, linear, and micellar components. Membranes pretreated with papain revealed a smooth surface area still capable of adhering bacterial antigens at a reduced rate (especially 068). Furthermore, additional 0 and K.antigens could be removed from potassium chloride and papain treated membranes after incubation with triton X100, indicating strong interaction between bacterial and integral brush-border membrane components. The globular particles of 5 nm diameter bound biospecifically to concanavalin A covalently linked to cyanogen-bromide-activated ’Sepharose’ as well 1 2
Lancet, 1977, i, 1293 Mondorf, W., Kinne, R., Scherberich, J. E., Falkenberg, F. Clin. chim. Acta,
1972, 37, 25. 3. Seherberich, J. E., Falkenberg, F., Mondorf, W., Müller, H., Pfleiderer, G. ibid. 1974, 55, 179 4. Scherberich, J. E., Schäfer, K., Gauhl, C., Sietzen, W., Mondorf, W., Schoeppe, W. Paper read at the 12th Symp. Ges. Nephrol. held in Bonn Sept. 28-Oct 1, 1977. Munich (in the press). 5. Seherberich, J. E., Gauhl, C., Mondorf, W. in Affinity Chromatography (edited by Hoffman and Ostenhoff). Oxford (in the press).
wheat-germ agglutinin sepharose.s.6 Soluble wheat-germ agglutinin and concanavalin A caused the nodules to aggregate. This finding supports the idea that the main part of brush-border surface proteins is rich in carbohydrates, especially galactose, mannose, and N-acetylglucosamine. The particles capable of attaching 0 and K antigens from E. coli would be equivalent to concanavalin A and wheat-germ agglutinin membrane receptor sites. These membrane surface antigens are excreted at an increased rate into urine of patients with kidney diseases3. ’.8 and can be isolated from urine by immunosorption.9 Our results sugas to
gest that brush-border membranes of human kidney carry at least two kinds of receptor for E. coli antigens. One receptor site might parallel the presence. of peripheral glycoprotein nodules, which are sensitive to proteolysis. This receptor expresses low and medium affinity for 0 and K antigens, respectively ;its binding is abolished by potassium chloride without structural change of the receptor protein, indicating electrostatic interactions ; proteolytic attack cleaves off adherent bacterial antigens as well as the receptor protein from the membrane matrix. The other high-affinity receptor site, which may be anchored in the membrane core, can only be released by detergents and only with additional bound bacterial antigen, and leads to membrane disintegration.
University of Frankfurt/Main, 6 Frankfurt am Main 70, West Germany
E. SCHERBERICH K. SCHÄFER W. MONDORF
Department of Microbiology and Virology, University of Frankfurt/Main
CORNELIA GAUHL W. SIETZEN
J.
Department of Nephrology, Centre for Internal Medicine,
LOW-DOSE HEPARIN
SIR,-The pioneer contribution of Dr J. G. Sharnoff in the of low-dose heparin to prevent postoperative thromboembolism is generally acknowledged. However, for Dr Sharnoff to claim (Nov. 19, p. 1087) that in "more than 3000 major operations there have been no serious haemorrhages" is to strain credulity. In the International Multicentre Trial,’ 5 out of 2076 control patients died from postoperative haemorrhage (versus 4 deaths in 2045 heparin-treated patients). Whether hasmorrhagic complications attributed to low-dose heparin are avoidable by monitoring the dose of heparin remains conjectural. Mr Britton and his colleagues (Sept. 17, p. 604) are discouraged by the fact that 6 out of some 2000 of their patients had significant postoperative bleeding while on low-dose heparin. But the Oxford surgeons have given only one side of the equation : they mention 2 deaths from pulmonary embolism among their patients, whereas they might reasonably have expected 10 such deaths (assuming a death rate of 0.5% from pulmonary embolism in postoperative patients given no prophylaxis2). It is unrealistic to expect potent drugs to have no sideeffects, and the question at issue is whether the benefit/risk ratio favours low-dose heparin prophylaxis. The conclusions of the Council on Thrombosis of the American Heart Association3 are worth repeating: "Presently available data indicate that low-dose heparin will significantly diminish postoperative deep venous thrombosis and pulmonary embolism in patients over the age of 40 subjected to major elective abdomino-thoracic surgery. [This regimen] is well tolerated by the patient and requires no laboratory monitoring. However, it does prouse
...
Scherberich, J. E., Mondorf, W. Prot. biol. Fluids, 1975, 23, 575. Mondorf, W., Carpenter, C. B., Scherberich, J. E., Merrill, J. P. ibid. 1973, 21, 493. 8. Scherberich, J. E., Mondorf, W., Fassbinder, W., Koch, K. Proc. Eur. Dial. Transplant. Ass. 1976, 13, 159. 9. Scherberich, J. E., Falkenberg, F., Stefanescu, T., Mondorf, W. in Chromatography of Synthetic and Biopolymers (edited by R. Epton) Bd 2; vol. II. (In the press.) 1. International Multicentre Trial Lancet, 1975, ii, 45. 2. Hume, M., Sevitt, S., Thomas, D. P. Venous Thrombosis and Pulmonary Embolism. Cambridge, Massachusetts, 1970. 3. Council on Thrombosis of the American Heart Association. Circulation, 1977, 55, 423A. 6. 7.
Lodging-houses attract people already in poor health and a mortality higher than in the general population might thus be A small area can have a great influence on the mormuch larger area and this "common lodging-house effect" may be a feature of public-health statistics in inner city
expected.
tality of a areas.
Department of Physics, Westminster Hospital,
London SW1
Liverpool
Area Health
Authority
R. F. MOULD K. WRIGHTON D. S. PICKUP
ESCHERICHIA COLI RECEPTORS ON HUMAN KIDNEY BRUSH-BORDER MEMBRANES
SIR,-We read with interest your editorial on Bacterial Adhesiveness and the Gut.’ Since attachment of bacteria might be one essential feature in the pathogenesis of infectious diseases, elucidation of interactions of bacterial antigens and constituents of the epithelial plasma membrane surface is of considerable interest. We have been studying brush-border membranes isolated from human kidney cortex.2,3 In an attempt to detect adherence of bacterial constituents to biomembranes, a property which may be relevant to the pathogenesis of some kidney diseases, we incubated kidney brush-border membranes with purified 0 and K antigens of Escherichia coli (013, 068, Kll, K64) for 4 h at 370C then overnight at 4°C.’ After extensive washing the plasma membranes were solubilised by papain, bromelains (protein/enzyme ratio 20/1, w/w), 3 mol/1 potassium chloride, ’Triton X100’ (0.01-1 %), and sodium desoxycholate (D.O.C., 0.2-1.2%). After centrifugation (1 h, 60 000 g) 0 and K antigens and soluble brush-border constituents were looked for by double immunodiffusion with antisera directed against bacterial 0 and K antigens and brush-border membranes.2-4 While none of the E. coli antigens studied could be detected in the supernatants of the controls, treatment with potassium chloride and especially papain, triton X100, and D.O.C. caused release of bacterial 0 and K components, thus indicating previous attachment to the plasma membranes. Soluble brush-border antigens were found in supernatants after digestion with papain (bromelains) and after treatment with detergents but not after potassium chloride. Negative staining of the untreated brush-border membrane surface showed numerous globular particles of 5 nm diameter bound to a 7-8 nm linear constituent sticking to the membrane matrix.s These nodules could be selectively removed after limited proteolysis (15 min); however, incubation with hypotonic solution (distilled water) and potassium chloride was not effective while detergents (triton, D.O.C.) caused solubilisation of globular, linear, and micellar components. Membranes pretreated with papain revealed a smooth surface area still capable of adhering bacterial antigens at a reduced rate (especially 068). Furthermore, additional 0 and K.antigens could be removed from potassium chloride and papain treated membranes after incubation with triton X100, indicating strong interaction between bacterial and integral brush-border membrane components. The globular particles of 5 nm diameter bound biospecifically to concanavalin A covalently linked to cyanogen-bromide-activated ’Sepharose’ as well 1 2
Lancet, 1977, i, 1293 Mondorf, W., Kinne, R., Scherberich, J. E., Falkenberg, F. Clin. chim. Acta,
1972, 37, 25. 3. Seherberich, J. E., Falkenberg, F., Mondorf, W., Müller, H., Pfleiderer, G. ibid. 1974, 55, 179 4. Scherberich, J. E., Schäfer, K., Gauhl, C., Sietzen, W., Mondorf, W., Schoeppe, W. Paper read at the 12th Symp. Ges. Nephrol. held in Bonn Sept. 28-Oct 1, 1977. Munich (in the press). 5. Seherberich, J. E., Gauhl, C., Mondorf, W. in Affinity Chromatography (edited by Hoffman and Ostenhoff). Oxford (in the press).
wheat-germ agglutinin sepharose.s.6 Soluble wheat-germ agglutinin and concanavalin A caused the nodules to aggregate. This finding supports the idea that the main part of brush-border surface proteins is rich in carbohydrates, especially galactose, mannose, and N-acetylglucosamine. The particles capable of attaching 0 and K antigens from E. coli would be equivalent to concanavalin A and wheat-germ agglutinin membrane receptor sites. These membrane surface antigens are excreted at an increased rate into urine of patients with kidney diseases3. ’.8 and can be isolated from urine by immunosorption.9 Our results sugas to
gest that brush-border membranes of human kidney carry at least two kinds of receptor for E. coli antigens. One receptor site might parallel the presence. of peripheral glycoprotein nodules, which are sensitive to proteolysis. This receptor expresses low and medium affinity for 0 and K antigens, respectively ;its binding is abolished by potassium chloride without structural change of the receptor protein, indicating electrostatic interactions ; proteolytic attack cleaves off adherent bacterial antigens as well as the receptor protein from the membrane matrix. The other high-affinity receptor site, which may be anchored in the membrane core, can only be released by detergents and only with additional bound bacterial antigen, and leads to membrane disintegration.
University of Frankfurt/Main, 6 Frankfurt am Main 70, West Germany
E. SCHERBERICH K. SCHÄFER W. MONDORF
Department of Microbiology and Virology, University of Frankfurt/Main
CORNELIA GAUHL W. SIETZEN
J.
Department of Nephrology, Centre for Internal Medicine,
LOW-DOSE HEPARIN
SIR,-The pioneer contribution of Dr J. G. Sharnoff in the of low-dose heparin to prevent postoperative thromboembolism is generally acknowledged. However, for Dr Sharnoff to claim (Nov. 19, p. 1087) that in "more than 3000 major operations there have been no serious haemorrhages" is to strain credulity. In the International Multicentre Trial,’ 5 out of 2076 control patients died from postoperative haemorrhage (versus 4 deaths in 2045 heparin-treated patients). Whether hasmorrhagic complications attributed to low-dose heparin are avoidable by monitoring the dose of heparin remains conjectural. Mr Britton and his colleagues (Sept. 17, p. 604) are discouraged by the fact that 6 out of some 2000 of their patients had significant postoperative bleeding while on low-dose heparin. But the Oxford surgeons have given only one side of the equation : they mention 2 deaths from pulmonary embolism among their patients, whereas they might reasonably have expected 10 such deaths (assuming a death rate of 0.5% from pulmonary embolism in postoperative patients given no prophylaxis2). It is unrealistic to expect potent drugs to have no sideeffects, and the question at issue is whether the benefit/risk ratio favours low-dose heparin prophylaxis. The conclusions of the Council on Thrombosis of the American Heart Association3 are worth repeating: "Presently available data indicate that low-dose heparin will significantly diminish postoperative deep venous thrombosis and pulmonary embolism in patients over the age of 40 subjected to major elective abdomino-thoracic surgery. [This regimen] is well tolerated by the patient and requires no laboratory monitoring. However, it does prouse
...
Scherberich, J. E., Mondorf, W. Prot. biol. Fluids, 1975, 23, 575. Mondorf, W., Carpenter, C. B., Scherberich, J. E., Merrill, J. P. ibid. 1973, 21, 493. 8. Scherberich, J. E., Mondorf, W., Fassbinder, W., Koch, K. Proc. Eur. Dial. Transplant. Ass. 1976, 13, 159. 9. Scherberich, J. E., Falkenberg, F., Stefanescu, T., Mondorf, W. in Chromatography of Synthetic and Biopolymers (edited by R. Epton) Bd 2; vol. II. (In the press.) 1. International Multicentre Trial Lancet, 1975, ii, 45. 2. Hume, M., Sevitt, S., Thomas, D. P. Venous Thrombosis and Pulmonary Embolism. Cambridge, Massachusetts, 1970. 3. Council on Thrombosis of the American Heart Association. Circulation, 1977, 55, 423A. 6. 7.
