An oral screening procedure to determine the sensitizing capacity of infant feeding formulae.
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Animals↗
Biomedical subjects
R R Coombs
Publications and source records attributed to R R Coombs.
Class of serum antibodies towards Salmonella enteritidis in gastro-enteritis, as measured by mixed reverse passive antiglobulin haemagglutination (MRPAH).
Sera taken from a well-mapped epidemic of Salmonella enteritidis gastro-enteritis among school children and teachers have been tested for antibodies of the IgG, IgM and IgA classes by MRPAH (mixed reverse passive antiglobulin haemagglutination) and for IgG and IgM classes by ELISA. When suitable threshold titres were chosen all sera taken up to 10 days after infection were negative by MRPAH, whereas all samples but one taken between day 16 and 48 showed the presence of antibodies of each three immunoglobulin classes. IgG antibody titres often remained elevated one year after infection whereas IgM and particularly IgA antibodies returned to negative. Up to the 28th day the IgG antibody titre showed a logarithmic increase with time, whereas no simple relationship was observed for the IgM and IgA antibody responses. Estimation of the regression equations for the titres measured by ELISA and MRPAH shows agreement between the two methods.
Antibodies, Bacterial↗
Effect of heat on the anaphylactic-sensitising capacity of cows' milk, gots' milk, and various infant formulae fed to guinea-pigs.
Cows' milk--fresh, boiled, and processed in different ways for the domestic market, and various infant milk formulae--was investigated for its sensitising capacity in the guinea-pig after being fed for 37 days. The anaphylactic sensitising capacity was considerably reduced by heat-treatment. As heat becomes more intense and more prolonged so beta-lactoglobulin and casein become less sensitising. It should be stressed that these were results from experiments on guinea-pigs drinking milk. Should they be found to apply to the human infant too, it seems that it would not be impossible to manufacture a non-sensitising but fully nutritive milk product. The sensitising capacity of fresh and boiled goats' milk was examined too, and it was found that boiling reduced the sensitising capacity to an even greater extent than was the case with cows' milk.
Animals↗
Measurement of human serum IgE and IgA by reverse passive antiglobulin haemagglutination.
Serum IgE levels can be measured by reverse passive antiglobulin haemagglutination (RPAH) of trypsin-treated human or sheep red cells coupled to sheep IgG anti-human IgE by chromic chloride. The results show a high correlation with those obtained by the radioactive single radial immunodiffusion method. Interfering anti-sheep IgG factors can be easily removed by absorption with small amounts of whole sheep or bovine serum cross-linked with glutaraldehyde. Standardisation with the British standard for IgE shows that the detection limit of the RPAH method is 0.5 IU/ml (1.2 ng/ml). The system is therefore comparable in sensitivity to the paper radio-immunosorbent test, and has the advantages of being simple, rapid and cheap. The RPAH method can be used to measure any class of immunoglobulin. For IgA the detection limit is found to be 10(-4) IU/ml (1.4 ng/ml).
Absorption↗
Comparison of red-cell linked anti-IgE and 125I-labelled anti-IgE in a solid-phase system for the measurement of IgE specific for castor bean allergen.
The report described the development of a mixed reverse (solid-phase) passive antiglobulin haemadsorption (MRsPAH) test for specific IgE antibody to castor bean allergen. The allergen is immobilised by formalin fixation in the wells of polyvinyl chloride microtitre plates. After allowing allergen-specific antibodies in the test serum to bind to the allergen, plates are washed thoroughly, and red cells coupled by chromic chloride to sheep IgG anti-human IgE are used to detect specifically bound IgE. This system was compared with a solid-phase radioimmunoassay in which 125I-labelled anti-IgE was substituted for the antiglobulin-linked red cells of the MRsPAH test; the earlier stages of both tests being the same. 12 sera, 10 from patients with allergic asthma to castor bean allergen and two from non-allergic controls, were tested for castor-bean-specific serum IgE by both methods and the results showed high correlation. The MRsPAH tst for allergen-specific serum IgE provides a useful alternative to the RAST system, being free of the disadvantages inherent in the use of radio-labelled materials.
Allergens↗
Early rheumatoid-like joint lesions in rabbits drinking cows' milk.
In a small experiment of 6 animals/group it was again shown that infiltrative synovial lesions could be induced in rabbits by the simple expedient of having the rabbits drink cows' milk over a 12-week period. Drinking 1/2-3/4 pint/day probably affords a small, but repeated, antigenic stimulation from intestinal absorption.
Animals↗
Early rheumatoid-like joint lesions in rabbits injected with foreign serum. IV. Influence of delayed-type hypersensitivity.
Intradermal injection of rabbits with lipid-coupled bovine serum proteins or bovine serum itself prior to a regimen of intravenous injections of bovine serum enhanced the incidence of joint lesions over that seen in animals receiving the intravenous regimen only. This increased of synovial lesions appeared, however, to be unrelated, either to the state of delayed hypersensitivity or to the concentration of passive haemagglutinating antibodies to bovine serum proteins in these animals. Lipid-coupled bovine serum, given as a first course in a regimen of intravenous injections, was no more arthritogenic than the native proteins and, as a second course series of intravenous injections, was definitely less arthritogenic.
Animals↗
Early rheumatoid-like lesions in rabbits injected with foreign serum. V. Attempted super-imposition of allergization to cartilage collagen.
Intradermal injection of bovine articular type II collagen produced, as expected, joint lesions in rats. However, this collagen preparation failed (1) to produce joint lesions in rabbits or (2) to exacerbate joint lesions in rabbits formed in the serum sickness model. Collagen extracted from rabbit xiphoid cartilage failed to show arthritogenic properties on intradermal injection in either rats or rabbits. It also failed to exacerbate joint lesions in the serum sickness model.
Animals↗
Evidence that the fourth component of complement (C4) is carried on a high proportion of normal guinea-pig B lymphocytes.
The fourth component of complement (C4) has been demonstrated on the cell membrane of guinea-pig B lymphocytes isolated from blood, lymph nodes and spleen. In lymph nodes, at least, the C4-positive cells also carry receptors for C3 and most bind IgG-Fc. Few, if any, T lymphocytes have detectable C4. Resynthesis of cell-surface C4 could not be shown following in vitro culture of lymphocytes stripped of C4 by proteolytic enzymes, and it is likely that the C4 is passively acquired in vitro from tissue fluids, possibly by a mechanism similar to that involved in the binding of C4 (Chido and Rodgers determinants) to human erythrocytes.
Animals↗
IgA anti-gliadin antibodies in coeliac disease.
Sixty-two sera from children under investigation for gastrointestinal disease were tested for IgA, IgG and IgM antibodies to gliadin by two different methods: an immunofluorescent (IF) test, and a mixed reverse (solid-phase) passive antiglobulin haemadsorption (MRSPAH) test. There was good agreement between the tests. Both tests detected gliadin antibodies of IgG and IgA class in sera from children with active coeliac disease, which tended to disappear when a strict gluten-free diet was instituted. Serum antibodies to gliadin of IgA class were associated with severe small intestinal villous atrophy and were found almost exclusively in coeliac disease. Gliadin antibodies of IgG class were less disease-specific and were occasionally detected in sera from children with gastrointestinal disease other than coeliac disease--notably in sera from children with transient gluten intolerance.
Adolescent↗
Interaction of antibody-aggregated C4 and guinea-pig red cells: coagglutination phenomenon of Bordet and Gengou.
The component of bovine serum (coagglutinogen) responsible for coagglutination of guinea-pig red cells has been shown to be c4, as anticipated from our previously reported findings on human serum. To effect coagglutination, the C4 needs to be aggregated by antibody; thereby probably increasing the avidity of the C4 for the receptors on guinea-pig red cells. The coagglutinating activity is lost if univalent Fab anti-C4 is used, but it can be restored by adding IgG antibody to the Fab. A procedure is described for producing antibody reagents to human or bovine C4 by injecting guinea-pigs with well-washed coagglutinated guinea-pig red cells.
Animals↗
Antibody-dependent cellular cytotoxicity in the guinea pig: the role of the Kurloff cell.
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Animals↗
Measure of rheumatoid factor in human sera by passive haemagglutination of human erythrocytes carrying immunoglobulin linked by chromic chloride.
Serum rheumatoid factor in sero-positive patients with rheumatoid arthritis may be measured by passive haemagglutination of trypsin-treated human red cells linked with heat-aggregated human IgG by chromic chloride. The results show excellent correlation with those obtained with the classical Rose-Waaler test. The sera may be tested unheated and do not require preliminary absorption with red cells. By this test procedure it should also be possible to analyse the species, allotypic and conformational specificity of different rheumatoid factors.
Animals↗
Serological and physicochemical reactivity of bovine erythrocytes before and after trypsin treatment.
On partition in aqueous polymer two-phase systems containing dextran, poly(ethyleneglycol) (PEG), and PEG substituted with charged or hydrophobic groups "inagglutinable" ox erythrocytes showed more negative surface charge and less hydrophobicity than "agglutinable" ox erythrocytes. Tryspin treatment of the erythrocytes increased the agglutinability, reduced the negative charge, and seemed to increase the liability to hydrophobic interaction. Haemagglutination of highly negatively charged ox erythrocytes is almost impossible to accomplish by antibody against the ox erythrocytes alone or against IgG antigen linked to the erythrocytes in passive haemagglutination. Likewise, reverse passive (antiglobulin) haemagglutination cannot be accomplished with these cells when immunoglobulin antigens of moderate molecular size (less than or equal to 900,000) are used. However, these cells may be agglutinated when a non-charged carrier such as a bacterium coated with sensitizing antibody (immunoglobulin) is used to bridge the antiglobulin-coupled erythrocytes in a mixed latticer aggllutinate. Such a bridging can also be accomplished by heat aggregation of the immunoglobulin antigen.
Animals↗
Early rheumatoid-like joint lesions in rabbits injected with foreign serum or milk proteins. III. Influence of concomitant IgE-like antibodies and of the breed of rabbit.
The presence of circulating IgE-like antibody was found not to enhance the induction of joint lesions, of moderate or greater intensity, by intravenous injection of bovine serum, but did make mild joint lesions more frequent. There was a positive correlation between increased white cell effusion into the joint fluid and joint lesions of moderate or greater intensity. Different breeds of rabbit were shown to produce different incidences of lesions suggesting a genetic influence on the development of rheumatoid-like joint lesions. The Old English breed was found to be particularly sensitive.
Animals↗
The coagglutination phenomenon of Bordet and Gengou involves a reaction between antibody-aggregated fourth component of complement and a receptor on guniea pig red cells.
The coagglutination phenomenon of Bordet and Gengou has been re-investigated. Many of the original observations have been confirmed. However, the explanation of the phenomenon has been found to be more special than that offered by Bordet and Gengou, who envisaged 'entrainment; or enmeshment of guinea pig red cells by lattices formed by antibodies reacting with serum proteins. We found that, so far as human serum is concerned, coagglutination of guinea pig red cells is confined to an activity of the fourth component of complement following its reaction with antibody. The nature of the association between antibody-reacted or antibody-aggregated C4 and the receptor on the guinea pig red cells is still to be elucidated.
Agglutination↗
Experiments in mice and rats on the induction of joint lesions following injections of serum and in chronic virus infection.
Rats and mice, in contrast to rabbits, appeared to be insusceptible to the development of rheumatoid-like joint lesions on repeated injections with bovine serum--the serum sickness model. Persistent infection of mice with the lactic dehydrogenase virus likewise failed to induce joint lesions.
Animals↗
The production of anti-a1 agglutinins in A-like rabbits injected with human group A1 erythrocytes.
A-like and non-A-like rabbits were injected with human group A1 erythrocytes. The rabbit sera were examined serologically for their hemagglutination patterns with human red cells of groups A1 and A2 before and after sequential adsorption with human group O, B and A2 erythrocytes. The A-like rabbits produced specific anti-A1 heteroagglutinins that resisted further adsorptions with group A2 cells. The tissues of A-like rabbits obviously do not contain antigenic configurations equivalent to those on human group A1 erythrocytes. Cross-reacting antibodies were also formed, by the non-A-like rabbits especially, as evidenced by the increased titer of agglutinins reactive with human group B red cells.
ABO Blood-Group System↗