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CIRCULATING ANTIBODIES IN MULTIPLE SCLEROSIS
164 as the child grows up a suitable would be " infantile racial staining ". This need give offence to no-one, and would avoid the inevitable confusion with mongoloid idiocy or Langdon Down’s
gradually disappears name
syndrome. H. R. E. WALLIS.
Bath.
CIRCULATING ANTIBODIES IN MULTIPLE SCLEROSIS of circulating autoantibodies in detection SiR,ŃThe certain types of thyroid disease has stimulated general
interest in the part played by autoimmune mechanisms in the pathogenesis of human disease. Simple serological tests have been widely used to investigate possible autoimmune reactions in various conditions. I have performed complement-fixation tests on human serum using extracts in saline of normal human tissues. Certain of the sera tested, particularly those obtained from patients with multiple sclerosis, reacted preferentially with normal human brain. Fresh cerebral tissue was obtained at necropsy, homogenised, and extracted in an equal volume of cold normal saline. The tissues were taken from blood-group-0 Rh-positive males and females dying without evidence of brain disease. Serum was obtained from patients in whom a confident clinical diagnosis of multiple sclerosis had been made, and from patients with a number of other neurological disorders. Sera were also collected from patients with other illnesses of comparable severity in whom there was no clinical evidence of disease of the central nervous system. The complement-fixation test used was a 5-volume micro-technique (unit volume 0’02 ml.; haemolytic system contained in 2 volumes): 21/2 M.H.D.so of complement were added and fixation was allowed to continue overnight at 4"C. Sera diluted 1:4 were inactivated and tested in batches, and known positive and negative control sera were included in each batch. A positive result was recorded if less than 50% haemolysis occurred, provided control tests were satisfactory. Positive and doubtful reactions were repeated.
A total of 153
sera were
tested. These
were
taken from 119
patients with diseases affecting the central nervous system and from 34 patients with other diseases not primarily affecting the nervous system. The results of complement-fixation tests carried out using saline extracts of normal human brain are given in the table. 32 out of the 153 sera tested gave a positive result (21 %). 24 of these positive sera were obtained from the patients with multiple sclerosis (41 % of 59 cases); 6 were from patients with
affecting the central nervous system (10% of 60 from patients without clinical evidence of any neurological disorder (5-9% of 34 cases). The difference between the incidence of positive results in the three groups is highly significant (P< 0-001). When only strong reactions, in which the serum titre is 1:8 or greater, are accepted as positive, the difference between the incidence of positive results in multiple sclerosis and among other diseases affecting the central nervous system remains significant: 14 (24%) of the patients with multiple sclerosis gave serum titres of 1:8 or greater and only two other sera gave similarly strong reactions (0-01 > p > 0-001). other diseases cases); and 2
were
Serum titres of 1:32 or greater were obtained with 8 sera, 7 from patients with multiple sclerosis and 1 from a patient with carotid-artery thrombosis. The highest dilution of any serum still giving a positive reaction was 1:256. These results agree with the findings of other workers who also obtained positive complement-fixation reactions using the sera of patients with multiple sclerosis and extracts made from normal brain or from the brains of subjects who had died of the disease. This suggests that in multiple sclerosis circulating antibodies are present which are capable of reacting with human brain. However, though positive sera behaved in their reactions as if they contained antibodies not normally present, electrophoresis of the sera showed that the mean of the percentages of gamma-globulin in the positive sera did not differ significantly from the mean percentage of gamma-globulin in the negative sera. The " complement-fixation " reactions may therefore be due to the actions of substances other than antibodies, and may result for example from " lipid-lipid interactions " or from enzymic removal of complement. No evidence of reaction with autologous tissue has been sought, and it cannot be claimed that the positive results are due to the presence of circulating autoantibodies. When the results are taken in conjunction with the results of experiments in which homologous and autologous brain tissues is injected into animals there is more support for the contention that autoimmune mechanisms are concerned in the pathogenesis of multiple sclerosis. The majority of the cases in this study were under the care of Dr. R. S. Allison, consultant neurologist, Royal Victoria Hospital, Belfast, to whom I am indebted for help and encouragement. Royal Victoria Hospital, Belfast.
S. D. ROBERTS.
TITRES OF REACTIONS AND DISTRIBUTION OF POSITIVE RESULTS AMONGST SERA REACTING PREFERENTIALLY WITH A SALINE EXTRACT OF HUMAN BRAIN
gradually disappears name
syndrome. H. R. E. WALLIS.
Bath.
CIRCULATING ANTIBODIES IN MULTIPLE SCLEROSIS of circulating autoantibodies in detection SiR,ŃThe certain types of thyroid disease has stimulated general
interest in the part played by autoimmune mechanisms in the pathogenesis of human disease. Simple serological tests have been widely used to investigate possible autoimmune reactions in various conditions. I have performed complement-fixation tests on human serum using extracts in saline of normal human tissues. Certain of the sera tested, particularly those obtained from patients with multiple sclerosis, reacted preferentially with normal human brain. Fresh cerebral tissue was obtained at necropsy, homogenised, and extracted in an equal volume of cold normal saline. The tissues were taken from blood-group-0 Rh-positive males and females dying without evidence of brain disease. Serum was obtained from patients in whom a confident clinical diagnosis of multiple sclerosis had been made, and from patients with a number of other neurological disorders. Sera were also collected from patients with other illnesses of comparable severity in whom there was no clinical evidence of disease of the central nervous system. The complement-fixation test used was a 5-volume micro-technique (unit volume 0’02 ml.; haemolytic system contained in 2 volumes): 21/2 M.H.D.so of complement were added and fixation was allowed to continue overnight at 4"C. Sera diluted 1:4 were inactivated and tested in batches, and known positive and negative control sera were included in each batch. A positive result was recorded if less than 50% haemolysis occurred, provided control tests were satisfactory. Positive and doubtful reactions were repeated.
A total of 153
sera were
tested. These
were
taken from 119
patients with diseases affecting the central nervous system and from 34 patients with other diseases not primarily affecting the nervous system. The results of complement-fixation tests carried out using saline extracts of normal human brain are given in the table. 32 out of the 153 sera tested gave a positive result (21 %). 24 of these positive sera were obtained from the patients with multiple sclerosis (41 % of 59 cases); 6 were from patients with
affecting the central nervous system (10% of 60 from patients without clinical evidence of any neurological disorder (5-9% of 34 cases). The difference between the incidence of positive results in the three groups is highly significant (P< 0-001). When only strong reactions, in which the serum titre is 1:8 or greater, are accepted as positive, the difference between the incidence of positive results in multiple sclerosis and among other diseases affecting the central nervous system remains significant: 14 (24%) of the patients with multiple sclerosis gave serum titres of 1:8 or greater and only two other sera gave similarly strong reactions (0-01 > p > 0-001). other diseases cases); and 2
were
Serum titres of 1:32 or greater were obtained with 8 sera, 7 from patients with multiple sclerosis and 1 from a patient with carotid-artery thrombosis. The highest dilution of any serum still giving a positive reaction was 1:256. These results agree with the findings of other workers who also obtained positive complement-fixation reactions using the sera of patients with multiple sclerosis and extracts made from normal brain or from the brains of subjects who had died of the disease. This suggests that in multiple sclerosis circulating antibodies are present which are capable of reacting with human brain. However, though positive sera behaved in their reactions as if they contained antibodies not normally present, electrophoresis of the sera showed that the mean of the percentages of gamma-globulin in the positive sera did not differ significantly from the mean percentage of gamma-globulin in the negative sera. The " complement-fixation " reactions may therefore be due to the actions of substances other than antibodies, and may result for example from " lipid-lipid interactions " or from enzymic removal of complement. No evidence of reaction with autologous tissue has been sought, and it cannot be claimed that the positive results are due to the presence of circulating autoantibodies. When the results are taken in conjunction with the results of experiments in which homologous and autologous brain tissues is injected into animals there is more support for the contention that autoimmune mechanisms are concerned in the pathogenesis of multiple sclerosis. The majority of the cases in this study were under the care of Dr. R. S. Allison, consultant neurologist, Royal Victoria Hospital, Belfast, to whom I am indebted for help and encouragement. Royal Victoria Hospital, Belfast.
S. D. ROBERTS.
TITRES OF REACTIONS AND DISTRIBUTION OF POSITIVE RESULTS AMONGST SERA REACTING PREFERENTIALLY WITH A SALINE EXTRACT OF HUMAN BRAIN