860 PRESERVATIVES IN HEPARIN
SERUM-PHENYTOIN, SEIZURES, AND
SIR,—Dr Ainley and his colleagues (March 26, p. 705) describe an allergic reaction to chlorocresol, the preservative in
ELECTROENCEPHALOGRAPHY
certain brands of heparin. Leo Laboratories are manufacturers of pure porcine mucous heparin, and the preservative we use is chlorbutol, which is not a phenol derivative. Adverse reactions to Leo heparin were monitored over a three year period between 1973 and 1976, during which time over 30 000 million units of heparin with chlorbutol were used worldwide, in addition to the bulk supplies made available to other companies. No allergic reactions to chlorbutol were reported during this period or since. Replacement of the multidose rubbercapped vial by single-dose preservative-free ampoules would create problems with certain concentrations of heparin, and single-dose ampoules are more expensive. We do make a preservative-free single-dose ampoule of 5000 units of heparin in 5 ml. Medical Department, Leo Laboratories Ltd, Hayes, Middlesex
B. T. MARSH
HEART-RATE VARIABILITY IN BRAIN-DAMAGED ADULTS
SIR,—Dr Lowensohn and his colleagues (March 19, p. 626) describe a diminished variation in heart-rate in patients with acute brain damage. By contrast, others have reported an increase in heart-rate variability associated with raised intracranial pressure (I.C.P.).12 It is not clear whether the reduction of "normal cyclic changes" refers to the variations over periods of tto 1 h which Lowensohn et al. describe or to variability on a much shorter time scale, which they show in the published example. From this example, it would appear that their observations could be related, at least in part, to alterations in sinus arrhythmia-the fluctuation of heart-rate with the respiratory cycle which is normal in all age-groups.34 This fluctuation is greater when breathing is slower; any comparison between patterns at different times and in different conditions must, therefore, take account of any change in breathing pattern. Sinus arrhythmia decreases in amplitude as the mean heart-rate rises and is not usually definable at rates above about 100 beats/min;-’ any comparison between heart-rate patterns must, therefore, take account also of the mean heartrate,’ since a decrease in variation would be unusual only it it accompanied a steady or decreasing heart-rate. The example of increased variability attributed by Lowensohn et al. to postoperative decrease in i.c.P. could, thus, be related to the decrease in mean heart-rate (130 to 100 beats/ min) and possibly also to a slower breathing pattern: the lower published trace seems to reveal, despite random variations, a background sinus arrhythmia with a breathing frequency of around 12/min; breathing might have been more rapid during the period of raised I.C.P. Although acute brain damage and raised :.c.p. may sometimes be associated with slow or periodic breathing, there is no consistency in this association, and there may often be rapid regular breathing;6 indeed we have found in neurosurgical patients that rapid breathing may be trig-
gered by rising I.C.P.7 For all these reasons, it would seem unwise to assign signifialteration in heart-rate pattern, particularly in the absence of information on the breathing pattern, in the evaluation of brain damage or dysfunction. cance to
Institute of Physiology, University of Glasgow, Glasgow G12 8QQ
in 3 of their 16 patients (19%); in 10 patients (62%) major seizures were abolished or reduced. The increase in serumphenytoin also caused an increase (mean 42%) in serumphenobarbitone. Could the reduction of seizures not be achieved merely by increasing the dosage of phenobarbitone or primidone, a much less dangerous procedure? Phenytoin can activate seizures in man, and, experimentally, at high dose levels all animals became irritable and had ataxia and convulsions.2 In Lambie’s series, 4 epileptics had serum-phenytoins over 80 µmol/l. E.E.G. recordings were not monitored. In a retrospective study we examined 131 mentally subnormal epileptics on long-term phenytoin. 70 (53%) had clinical evidence of toxicity which remitted, at least partly, after a reduction of phenytoin dosage, and serum-phenytoins of 2S µg/ml or more. The duration of phenytoin intoxication averaged 47 months. 18 patients permanently lost their ability to walk. In 122 (93%) pneumoencephalographic findings were abnormal. The statistical correlation between the degree of the cerebellar atrophy and the severity of epilepsy was less striking than the correlation between the cerebellar atrophy and the serum-phenytoin.3 The phenytoin-treated epileptics, especially those with phenytoin intoxication, had significantly more E.E.G. abnormalities than the 68 epileptics without phenytoin treatment. Because phenytoin intoxication can provoke both seizures and E.E.G. abnormalities,4 the conclusion that more severe epilepsy was being treated more effectively does not follow. In epileptics on long-term phenytoin,’ E.E.G.S were normal in 20%, and serum-phenytoin levels averaged 10 µg/ml. In the epileptics with abnormal E.E.G.S, the average serum-phenytoins were within the range 15-21 µg/ml. Approximately a third of the patients had seizures months or years apart and a mean serum-phenytoin of 12.0 µg/ml. In another third seizure intervals were measured in days, and the average serum-phenytoin was 18-0 g/ml. Thus there seems to be a relation between seizure frequency, serum-phenytoin, and E.E.G. abnormalities in epileptics under long-term phenytoin treatment. One can expect that there are at least some epileptics with phenytoinactivated seizures among drug-resistant patients with high serum-phenytoin. High serum levels of phenytoin may be hazardous to patients6 and of little benefit. The E.E.G. is of value in detecting the silent toxicity of phenytoin or other anti epileptic drugs. Roseman4 stated in 1961 that: "The minimal early slowing of the alpha activity seems to act as a titrating end point [for phenytoin]. Once this point is reached, not only has the therapeutic dose been exceeded but toxic symptoms and signs may be expected. Therefore, it is useless to push the dosage higher, particularly if control of seizures has not been effected." One cannot rely on serum concentrations alone. Some patients are very sensitive to phenytoin toxicity,’ and severe intoxication has been recorded at a phenytoin concentration of only 1 tg/Ml.7 In toxic combinations of anticonvulsants the individual drugs may have their concentrations within therapeutic range yet a toxic encephalopathy will be revealed by the E.E.G. Monitoring drug levels and E.E.G.S seems to be the method of choice for ensuring safe and effective medication in epileptics on multiple drug therapy. An example is sodium valproate which seems clinically to increase the effects of other anticon-
SHEILA JENNETT
Fitch, W., McDowall, D. G. in Brain Hypoxia (edited by J. B. Brierley and B. S. Meldrum); p. 113. London, 1971. 2. Heck, A. F. in Cerebral Blood Flow and Intracranial Pressure (edited by C. Fieschi); p. 486. Basle, 1972. 3. Jennett, S., McKillop, J. H.J. Physiol., Lond. 1970, 213, 58P. 4. Davies, C. T. M., Neilson, J. M. M.J. appl. Physiol. 1967, 22, 947. 5. Davies, C. T. M., Neilson, J. M. M. ibid. p. 943. 6. North, J. B., Jennett, S. Archs Neurol. 1974, 31, 338. 7 North, J. B., Jennett, S. Unpublished. 1.
SIR,—Lambie et al.’ favour raising serum-phenytoin concentrations, yet when this was done major seizures increased
1.
Lambie, D. G., Johnson, R. H., Nanda, R. N., Shakir, R. A. Lancet, 1976, ii, 386. 2. Levy, L. L, Fenichel, G. M. Neurology, 1965,15, 716. 3. Iivanainen, M., Viukari, M., Helle, E.-P. Unpublished. 4. Roseman, E. Neurology, 1961, 11, 912. 5. Stensrud, P. A., Palmer, H. Epilepsia, 1964, 5, 364. 6. Ghatak, N. R., Santoso, R. A., McKinney, W. M. Neurology, 1976, 26, 818 7. Ahmad, S., Laidlaw, J., Houghton, G. W., Richens, A. J. Neurol. Neurosurg. Psychiat. 1975, 38, 225.
861 vulsants
probably by displacing drugs
from
protein-binding
a raised brain and reduced plasma total concentration of phenytoin, as suggested by Patsalos and Lascelles.8 One possible explanation for the observations of Bardy et al.9 is that phenytoin toxicity was increased by valproate, causing frequent seizures and signs of intoxication. However, their findings are more probably attributable to the unreliable intake of drugs in outpatients. Such patients often reduce the intake of an earlier drug when a new one is added to their regimen but would take it in excess after getting more seizures.
sites.
Thus, valproate administration may result in
Department of Neurology, University Central Hospital of Helsinki, 00290 Helsinki 29, and Research Department, Rinnekoti Institute, Majalampi, Finland
MATTI IIVANAINEN MATTI VIUKARI
ALPHA-CHAIN DISEASE: EVIDENCE FOR COMMON CLONAL ORIGIN OF INTESTINAL IMMUNOBLASTIC LYMPHOMA AND PLASMACYTIC PROLIFERATION
SIR,—We have suggestedl2 that the malignant lymphomas which may arise in the late course of alpha-chain disease (&agr;-C.D.) were derived from the same B-cell clone as the initial plasma-cell proliferation. Morphological and ultrastructural data34 support this hypothesis but direct evidence was lacking. This is provided by our investigation of a 37-year-old Iranian female in whom a-C.D. was diagnosed in 1974 after a 2-month history of chronic small-intestinal obstruction. A 9 cm long jejunal segment, centered by a mucosal ulceration, was resected and showed the usual plasmacytic proliferation limited to the mucosal lamina propria, except within the ulceration area where it invaded the full thickness of the gut wall. The patient received monthly courses of prednisolone and melphalan and thereafter weekly injections of cyclophosphamide and oral tetracycline until April, 1976. She remained symptom-free during this period. Physical examination was normal, and intestinal absorption tests were normal on two occasions. However, the serum level of &agr;-C.D. protein remained stable in 1975. In April, 1976, the &agr;-c.D. protein had almost completely disappeared from the serum but was still found in the jejunal juice. A barium meal then revealed a large ulcer at the duodenojejunal junction. A nodular ulcerated tumour of 5 cm diameter was resected at this site. This tumour was predominantly made up of large lymphomatous cells with "immunoblastic" features,’with exceptional Reed-Sternberglike cells and some mature plasma cells with transitional forms between the latter and the large lymphoma cells. The adjacent small-intestinal mucosa showed a plasmacytic infiltration of the lamina propria but distal jejunum and distal ileum were histologically normal. Mesenteric lymph-nodes showed either a normal architecture or a massive plasmacytic proliferation extending through the capsule into the mesenteric fat.
Intracytoplasmic and membrane-bound immunoglobulins studied by direct immunofluorescenceon tumour cells obtained by gentle teasing of the resected intestine. Intracytoplasmic x chain was found only in the rare mature-looking were
plasma cells, whereas a high density of x chains was detectable at the surface of the large immunoblastic cells. Antisera to µ, S, y, x, and A chains yielded negative results. The large malignant cells also had a receptor for antigen-antibody complexes. The presence of membrane-bound a chains on the large im8. Patsalos, P. N., Lascelles, P. T. Lancet, 1977, i, 50. 9. Bardy, A., Han, *., Lehtovaara, R. Majuri, H. ibid. 1976, i, 1297. 1 Rambaud, J. C., Matuchansky, C. Lancet, 1973, i, 1430. 2. Brouet, J. C., Labaume, S., Seligmann, M. Br. J. Cancer, 1975, 31, suppl.
ii, p. 356. 3. Doe, W. F. ibid. p. 350. 4 Galian, A., Lecestre, M. J., Scotto, J., Bognel, C., Matuchansky, C., Rambaud, J. C. Cancer (in the press). 5 Preud’homme, J. L., Seligmann, M. Blood, 1972, 40, 777.
Immunoblast stained for anti-oc antibodies. The surface of this large immunoblast is surrounded by diffuse black thin layer due to specific staining by peroxidase coupled anti-a antibodies. This B immunoblast is devoid of endoplasmic reticulum; its nucleus contains small amounts of marginal heterochromatin and a very large nucleolus. The black staining of the erythrocyte on the lower left results from the M peroxidase activity. The section is counterstained with uranyl acetate and lead citrate (x 2800).
munoblastic cells was confirmed by immunoelectronmicroscopy using rabbit antibodies to Ig chains purified by immunoadsorption and coupled to horseradish peroxidase.6 The cell suspension was fixed by glutaraldehyde before incubation with these antibodies and further processed as previously described.6 As shown in the figure, specific staining of large cells was observed with anti-a antibodies whereas the reaction was negative with antibodies to x andchains. The sensitive threestage immunoperoxidase technique with the peroxidase/antiperoxidase sandwich procedurewas also applied to fixed smears of the tumour cells and allowed detection by optical
microscopy of« chains in the plasma cells and in the large lymphoma cells. The staining of the latter was probably cytoplasmic but may have represented surface a chains. These findings strongly support the hypothesis of a common clonal origin for the large immunoblastic lymphoma cells and the plasmacytic cells. Similar conclusions were drawn from the study of immunoblastic lymphomas arising in patients previously affected with other chronic lymphoid proliferations such as chronic lymphocytic leukaemia and Waldenstrom’s macroglobulinæmia.8 The a-c.D. protein had nearly disappeared from the serum of our patient when lymphoma developed. Thus, the monitoring of the a-c.D. protein level in serum or intestinal fluid may be misleading. J. C. BROUET Laboratory of Immunochemistry and Immunopathology (INSERM U 108), Research Institute on Blood Diseases, Hôpital Saint-Louis, Paris 10, France
D. Y. MASON F. DANON J. L. PREUD’HOMME M. SELIGMANN
Institute for Research into Anæmias, INSERM U 91, Hôpital Henri Mondor, Créteil, France
F. REYES
Tadj Pahlavi Cancer Institute, University of Tehran School of Medicine, Tehran, Iran
F. NAVAB
Department of Gastroenterology (INSERM U 54), Hôpital Saint-Lazare, Paris
A. GALIAN E. RENE J. C. RAMBAUD
6.
Reyes, F., Lejonc, J. L., Gourdin, M. F., Mannoni, P., Dreyfus, B. J. exp. Med. 1975, 141, 392. 7. Mason, D., Farrell, C., Taylor, C. R. Br. J. Hœmat. 1975, 31, 361. 8. Brouet, J. C., Preud’homme, J. L., Flandrin, G., Chelloul, N., Seligmann, M. J. nat. Cancer Inst. 1976, 56, 631.
SERUM-PHENYTOIN, SEIZURES, AND
SIR,—Dr Ainley and his colleagues (March 26, p. 705) describe an allergic reaction to chlorocresol, the preservative in
ELECTROENCEPHALOGRAPHY
certain brands of heparin. Leo Laboratories are manufacturers of pure porcine mucous heparin, and the preservative we use is chlorbutol, which is not a phenol derivative. Adverse reactions to Leo heparin were monitored over a three year period between 1973 and 1976, during which time over 30 000 million units of heparin with chlorbutol were used worldwide, in addition to the bulk supplies made available to other companies. No allergic reactions to chlorbutol were reported during this period or since. Replacement of the multidose rubbercapped vial by single-dose preservative-free ampoules would create problems with certain concentrations of heparin, and single-dose ampoules are more expensive. We do make a preservative-free single-dose ampoule of 5000 units of heparin in 5 ml. Medical Department, Leo Laboratories Ltd, Hayes, Middlesex
B. T. MARSH
HEART-RATE VARIABILITY IN BRAIN-DAMAGED ADULTS
SIR,—Dr Lowensohn and his colleagues (March 19, p. 626) describe a diminished variation in heart-rate in patients with acute brain damage. By contrast, others have reported an increase in heart-rate variability associated with raised intracranial pressure (I.C.P.).12 It is not clear whether the reduction of "normal cyclic changes" refers to the variations over periods of tto 1 h which Lowensohn et al. describe or to variability on a much shorter time scale, which they show in the published example. From this example, it would appear that their observations could be related, at least in part, to alterations in sinus arrhythmia-the fluctuation of heart-rate with the respiratory cycle which is normal in all age-groups.34 This fluctuation is greater when breathing is slower; any comparison between patterns at different times and in different conditions must, therefore, take account of any change in breathing pattern. Sinus arrhythmia decreases in amplitude as the mean heart-rate rises and is not usually definable at rates above about 100 beats/min;-’ any comparison between heart-rate patterns must, therefore, take account also of the mean heartrate,’ since a decrease in variation would be unusual only it it accompanied a steady or decreasing heart-rate. The example of increased variability attributed by Lowensohn et al. to postoperative decrease in i.c.P. could, thus, be related to the decrease in mean heart-rate (130 to 100 beats/ min) and possibly also to a slower breathing pattern: the lower published trace seems to reveal, despite random variations, a background sinus arrhythmia with a breathing frequency of around 12/min; breathing might have been more rapid during the period of raised I.C.P. Although acute brain damage and raised :.c.p. may sometimes be associated with slow or periodic breathing, there is no consistency in this association, and there may often be rapid regular breathing;6 indeed we have found in neurosurgical patients that rapid breathing may be trig-
gered by rising I.C.P.7 For all these reasons, it would seem unwise to assign signifialteration in heart-rate pattern, particularly in the absence of information on the breathing pattern, in the evaluation of brain damage or dysfunction. cance to
Institute of Physiology, University of Glasgow, Glasgow G12 8QQ
in 3 of their 16 patients (19%); in 10 patients (62%) major seizures were abolished or reduced. The increase in serumphenytoin also caused an increase (mean 42%) in serumphenobarbitone. Could the reduction of seizures not be achieved merely by increasing the dosage of phenobarbitone or primidone, a much less dangerous procedure? Phenytoin can activate seizures in man, and, experimentally, at high dose levels all animals became irritable and had ataxia and convulsions.2 In Lambie’s series, 4 epileptics had serum-phenytoins over 80 µmol/l. E.E.G. recordings were not monitored. In a retrospective study we examined 131 mentally subnormal epileptics on long-term phenytoin. 70 (53%) had clinical evidence of toxicity which remitted, at least partly, after a reduction of phenytoin dosage, and serum-phenytoins of 2S µg/ml or more. The duration of phenytoin intoxication averaged 47 months. 18 patients permanently lost their ability to walk. In 122 (93%) pneumoencephalographic findings were abnormal. The statistical correlation between the degree of the cerebellar atrophy and the severity of epilepsy was less striking than the correlation between the cerebellar atrophy and the serum-phenytoin.3 The phenytoin-treated epileptics, especially those with phenytoin intoxication, had significantly more E.E.G. abnormalities than the 68 epileptics without phenytoin treatment. Because phenytoin intoxication can provoke both seizures and E.E.G. abnormalities,4 the conclusion that more severe epilepsy was being treated more effectively does not follow. In epileptics on long-term phenytoin,’ E.E.G.S were normal in 20%, and serum-phenytoin levels averaged 10 µg/ml. In the epileptics with abnormal E.E.G.S, the average serum-phenytoins were within the range 15-21 µg/ml. Approximately a third of the patients had seizures months or years apart and a mean serum-phenytoin of 12.0 µg/ml. In another third seizure intervals were measured in days, and the average serum-phenytoin was 18-0 g/ml. Thus there seems to be a relation between seizure frequency, serum-phenytoin, and E.E.G. abnormalities in epileptics under long-term phenytoin treatment. One can expect that there are at least some epileptics with phenytoinactivated seizures among drug-resistant patients with high serum-phenytoin. High serum levels of phenytoin may be hazardous to patients6 and of little benefit. The E.E.G. is of value in detecting the silent toxicity of phenytoin or other anti epileptic drugs. Roseman4 stated in 1961 that: "The minimal early slowing of the alpha activity seems to act as a titrating end point [for phenytoin]. Once this point is reached, not only has the therapeutic dose been exceeded but toxic symptoms and signs may be expected. Therefore, it is useless to push the dosage higher, particularly if control of seizures has not been effected." One cannot rely on serum concentrations alone. Some patients are very sensitive to phenytoin toxicity,’ and severe intoxication has been recorded at a phenytoin concentration of only 1 tg/Ml.7 In toxic combinations of anticonvulsants the individual drugs may have their concentrations within therapeutic range yet a toxic encephalopathy will be revealed by the E.E.G. Monitoring drug levels and E.E.G.S seems to be the method of choice for ensuring safe and effective medication in epileptics on multiple drug therapy. An example is sodium valproate which seems clinically to increase the effects of other anticon-
SHEILA JENNETT
Fitch, W., McDowall, D. G. in Brain Hypoxia (edited by J. B. Brierley and B. S. Meldrum); p. 113. London, 1971. 2. Heck, A. F. in Cerebral Blood Flow and Intracranial Pressure (edited by C. Fieschi); p. 486. Basle, 1972. 3. Jennett, S., McKillop, J. H.J. Physiol., Lond. 1970, 213, 58P. 4. Davies, C. T. M., Neilson, J. M. M.J. appl. Physiol. 1967, 22, 947. 5. Davies, C. T. M., Neilson, J. M. M. ibid. p. 943. 6. North, J. B., Jennett, S. Archs Neurol. 1974, 31, 338. 7 North, J. B., Jennett, S. Unpublished. 1.
SIR,—Lambie et al.’ favour raising serum-phenytoin concentrations, yet when this was done major seizures increased
1.
Lambie, D. G., Johnson, R. H., Nanda, R. N., Shakir, R. A. Lancet, 1976, ii, 386. 2. Levy, L. L, Fenichel, G. M. Neurology, 1965,15, 716. 3. Iivanainen, M., Viukari, M., Helle, E.-P. Unpublished. 4. Roseman, E. Neurology, 1961, 11, 912. 5. Stensrud, P. A., Palmer, H. Epilepsia, 1964, 5, 364. 6. Ghatak, N. R., Santoso, R. A., McKinney, W. M. Neurology, 1976, 26, 818 7. Ahmad, S., Laidlaw, J., Houghton, G. W., Richens, A. J. Neurol. Neurosurg. Psychiat. 1975, 38, 225.
861 vulsants
probably by displacing drugs
from
protein-binding
a raised brain and reduced plasma total concentration of phenytoin, as suggested by Patsalos and Lascelles.8 One possible explanation for the observations of Bardy et al.9 is that phenytoin toxicity was increased by valproate, causing frequent seizures and signs of intoxication. However, their findings are more probably attributable to the unreliable intake of drugs in outpatients. Such patients often reduce the intake of an earlier drug when a new one is added to their regimen but would take it in excess after getting more seizures.
sites.
Thus, valproate administration may result in
Department of Neurology, University Central Hospital of Helsinki, 00290 Helsinki 29, and Research Department, Rinnekoti Institute, Majalampi, Finland
MATTI IIVANAINEN MATTI VIUKARI
ALPHA-CHAIN DISEASE: EVIDENCE FOR COMMON CLONAL ORIGIN OF INTESTINAL IMMUNOBLASTIC LYMPHOMA AND PLASMACYTIC PROLIFERATION
SIR,—We have suggestedl2 that the malignant lymphomas which may arise in the late course of alpha-chain disease (&agr;-C.D.) were derived from the same B-cell clone as the initial plasma-cell proliferation. Morphological and ultrastructural data34 support this hypothesis but direct evidence was lacking. This is provided by our investigation of a 37-year-old Iranian female in whom a-C.D. was diagnosed in 1974 after a 2-month history of chronic small-intestinal obstruction. A 9 cm long jejunal segment, centered by a mucosal ulceration, was resected and showed the usual plasmacytic proliferation limited to the mucosal lamina propria, except within the ulceration area where it invaded the full thickness of the gut wall. The patient received monthly courses of prednisolone and melphalan and thereafter weekly injections of cyclophosphamide and oral tetracycline until April, 1976. She remained symptom-free during this period. Physical examination was normal, and intestinal absorption tests were normal on two occasions. However, the serum level of &agr;-C.D. protein remained stable in 1975. In April, 1976, the &agr;-c.D. protein had almost completely disappeared from the serum but was still found in the jejunal juice. A barium meal then revealed a large ulcer at the duodenojejunal junction. A nodular ulcerated tumour of 5 cm diameter was resected at this site. This tumour was predominantly made up of large lymphomatous cells with "immunoblastic" features,’with exceptional Reed-Sternberglike cells and some mature plasma cells with transitional forms between the latter and the large lymphoma cells. The adjacent small-intestinal mucosa showed a plasmacytic infiltration of the lamina propria but distal jejunum and distal ileum were histologically normal. Mesenteric lymph-nodes showed either a normal architecture or a massive plasmacytic proliferation extending through the capsule into the mesenteric fat.
Intracytoplasmic and membrane-bound immunoglobulins studied by direct immunofluorescenceon tumour cells obtained by gentle teasing of the resected intestine. Intracytoplasmic x chain was found only in the rare mature-looking were
plasma cells, whereas a high density of x chains was detectable at the surface of the large immunoblastic cells. Antisera to µ, S, y, x, and A chains yielded negative results. The large malignant cells also had a receptor for antigen-antibody complexes. The presence of membrane-bound a chains on the large im8. Patsalos, P. N., Lascelles, P. T. Lancet, 1977, i, 50. 9. Bardy, A., Han, *., Lehtovaara, R. Majuri, H. ibid. 1976, i, 1297. 1 Rambaud, J. C., Matuchansky, C. Lancet, 1973, i, 1430. 2. Brouet, J. C., Labaume, S., Seligmann, M. Br. J. Cancer, 1975, 31, suppl.
ii, p. 356. 3. Doe, W. F. ibid. p. 350. 4 Galian, A., Lecestre, M. J., Scotto, J., Bognel, C., Matuchansky, C., Rambaud, J. C. Cancer (in the press). 5 Preud’homme, J. L., Seligmann, M. Blood, 1972, 40, 777.
Immunoblast stained for anti-oc antibodies. The surface of this large immunoblast is surrounded by diffuse black thin layer due to specific staining by peroxidase coupled anti-a antibodies. This B immunoblast is devoid of endoplasmic reticulum; its nucleus contains small amounts of marginal heterochromatin and a very large nucleolus. The black staining of the erythrocyte on the lower left results from the M peroxidase activity. The section is counterstained with uranyl acetate and lead citrate (x 2800).
munoblastic cells was confirmed by immunoelectronmicroscopy using rabbit antibodies to Ig chains purified by immunoadsorption and coupled to horseradish peroxidase.6 The cell suspension was fixed by glutaraldehyde before incubation with these antibodies and further processed as previously described.6 As shown in the figure, specific staining of large cells was observed with anti-a antibodies whereas the reaction was negative with antibodies to x andchains. The sensitive threestage immunoperoxidase technique with the peroxidase/antiperoxidase sandwich procedurewas also applied to fixed smears of the tumour cells and allowed detection by optical
microscopy of« chains in the plasma cells and in the large lymphoma cells. The staining of the latter was probably cytoplasmic but may have represented surface a chains. These findings strongly support the hypothesis of a common clonal origin for the large immunoblastic lymphoma cells and the plasmacytic cells. Similar conclusions were drawn from the study of immunoblastic lymphomas arising in patients previously affected with other chronic lymphoid proliferations such as chronic lymphocytic leukaemia and Waldenstrom’s macroglobulinæmia.8 The a-c.D. protein had nearly disappeared from the serum of our patient when lymphoma developed. Thus, the monitoring of the a-c.D. protein level in serum or intestinal fluid may be misleading. J. C. BROUET Laboratory of Immunochemistry and Immunopathology (INSERM U 108), Research Institute on Blood Diseases, Hôpital Saint-Louis, Paris 10, France
D. Y. MASON F. DANON J. L. PREUD’HOMME M. SELIGMANN
Institute for Research into Anæmias, INSERM U 91, Hôpital Henri Mondor, Créteil, France
F. REYES
Tadj Pahlavi Cancer Institute, University of Tehran School of Medicine, Tehran, Iran
F. NAVAB
Department of Gastroenterology (INSERM U 54), Hôpital Saint-Lazare, Paris
A. GALIAN E. RENE J. C. RAMBAUD
6.
Reyes, F., Lejonc, J. L., Gourdin, M. F., Mannoni, P., Dreyfus, B. J. exp. Med. 1975, 141, 392. 7. Mason, D., Farrell, C., Taylor, C. R. Br. J. Hœmat. 1975, 31, 361. 8. Brouet, J. C., Preud’homme, J. L., Flandrin, G., Chelloul, N., Seligmann, M. J. nat. Cancer Inst. 1976, 56, 631.
