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Biomedical subjects

R R Coombs

Publications and source records attributed to R R Coombs.

At least 73 records · Page 4Linked to original sources
PubMed1983

Immunoglobulin concentrations and bacterial antibody titres in breast milk from mothers of 'preterm' and 'term' infants.

IgA, IgM and IgG concentrations and their bacterial antibodies to E. coli, group B streptococci and Brucella abortus were measured in human breast milk collected from the 1st to 10th day post-partum from mothers delivered of 'preterm' infants (Premature Breast Milk or PBM) and from mothers delivered of term infants (Term Breast Milk or TBM). Reverse passive haemagglutination tests (RPH), rocket immuno-electrophoresis and mixed reverse passive antiglobulin haemagglutination tests (MRPAH) were employed. PBM at 2-5 days post-partum (though not beyond this period) contained higher IgA levels than did TBM, and this difference persisted even when total IgA was expressed as a proportion of total milk protein: in contrast the IgM and IgG contents of PBM and TBM were the same at both these postnatal ages. The titre of IgA antibody to E. coli, which was absorbable only by the corresponding bacteria, showed no significant difference between PBM and TBM, whereas the titres of IgA reacting with Br. abortus and, to a lesser extent group B streptococci, were higher in PBM than those in TBM. However the IgA which reacted with Br. abortus and group B streptococci was not specific to those organisms but was absorbed by all three bacteria studied. It is speculated that the high IgA content of early preterm milk and perhaps the presence of especially high titres of what appears to be a non-specific or cross-reacting bacterial IgA in such milk, may be immunologically advantageous to low birthweight infants fed on their own mother's milk.

Antibodies, Bacterial↗
PubMed1983

Naturally developing antibodies to wheat gliadin fractions and to other cereal antigens in rabbits, rats and guinea pigs on normal laboratory diets.

Rabbits, rats and guinea pigs on normal laboratory diets were examined for gliadin and other cereal antibodies comparable to those found in the sera of human coeliac patients. Many of the rabbits had very high levels of gliadin antibodies. Rats showed much lower titres more comparable to the findings in normal human sera. In both these species the reactivity was directed principally against the alpha-gliadins. The spectrum of reactivity against the prolamines of other cereals was again comparable to that of human coeliac sera. A difference, however, was the high reactivity with maize prolamine; this was decidedly lower in sera of coeliac patients. Guinea pigs were distinctive in having relatively no serum antibodies to wheat gliadin and also minimal reactivity to the albumins, globulins and glutenins of wheat. Normal guinea pigs did, however, have antibodies to oat and maize prolamines. Following parenteral injection with total ethanol-soluble wheat gliadin, guinea pigs developed high-titred antibodies, not only to wheat gliadin fractions 1-8 (alpha-, beta-, gamma- and omega-gliadins), but also to all the cereal prolamines except those of rice. These investigations are steps in the evaluation of the role of circulating gliadin antibodies in gluten-sensitive enteropathy.

Animals↗
PubMed1983

Immediate hypersensitivity reaction to beta-lactoglobulin in the epithelium lining the colon of guinea pigs fed cows' milk.

Isolated epithelia from the colons of guinea pigs fed cows' milk have been studied in vitro under short circuit current conditions. When challenged with beta-lactoglobulin (beta LG) from the basolateral side, a large, transient inward flowing current was recorded. Pharmacological and ion flux measurements indicated this was due to inappropriate chloride secretion. There was no effect of beta LG on normal epithelia. The effects of challenge with beta LG were abolished by pretreatment with indomethacin, a prostaglandin synthetase inhibitor. By exposing epithelia from water-drinking animals in vitro to serum from milk-drinking guinea pigs sensitivity to beta LG could be conferred.

Animals↗
PubMed1982

Cryopreservation of antibody-coupled red cells for use in immunoassays.

Red cells, trypsin-treated to render them more agglutinable and coupled with antiglobulin reagents, may be preserved by droplet freezing in liquid nitrogen. A 2% cell suspension in 0.45% w/v sodium chloride, 5% w/v sucrose and 10% w/v dextran 40 was used. After thawing the frozen pellets in phosphate-buffered saline at 40 degrees C, more than 80% cell recovery was obtained. Sheep and ox red cells preserved in this way were as satisfactory in antiglobulin and in reverse passive haemagglutination tests as unfrozen indicator red cells. Trypsin-treated human red cells coupled with anti-IgE could likewise be frozen and on reconstitution used to assay IgE in human serum. Reconstituted ox red cells were slightly less efficient in rosetting than cells which had not been frozen.

Animals↗
PubMed1982

An indirect haemadsorption procedure (MRSPAH) for detecting antibodies to respiratory syncytial virus.

A simple haemadsorption procedure for the detection of isotype specific antibodies to R.S. virus has been developed. Correlation between detection of R.S. virus IgG antibodies by mixed reverse (solid phase) passive antiglobulin haemadsorption (MRSPAH) and other serological procedures has been obtained. IgA antibody was detected in 62% of milk samples studied. The method is rapid, simple and uses commonly available serological reagents.

Antibodies, Viral↗
PubMed1982

Comparison of reverse passive antiglobulin haemagglutination with double antibody radioimmunoassay for estimation of total human serum IgE.

Serum IgE levels can be measured by reverse passive antiglobulin haemagglutination (RPAH) using trypsin-treated human red cells coupled to anti-human IgE by chronic chloride. The results are read after only 90 min incubation. RPAH and double antibody radioimmunoassay have been used to measure IgE levels in 100 sera, with levels ranging from 5 to 43,000 international units (i.u.)/ml. Correlation between the two assays was high over the whole range, provided that affinity-purified anti-IgE was used in the RPAH test. When two non-affinity-purified anti-IgE reagents were used in the RPAH, correlation was poor for sera with levels below 1000 i.u./ml. It is concluded that RPAH tests for IgE are of comparable sensitivity and specificity to radioimmunoassay procedures, and provide a useful simple, yet more rapid alternative.

Antibodies, Anti-Idiotypic↗
PubMed1982

T-lymphocyte and B-lymphocyte subpopulations infiltrating human mammary carcinomas.

Both T- and B-lymphocytes were found in human primary mammary carcinomas and were distributed in widely varying amounts, but in most tumors, T-lymphocytes predominated. A small percentage of the T-lymphocytes expressed receptors for the Fc portion of IgG (Fc gamma R), but very few had receptors for C3 (C3+) (comparable to the findings in blood). A prominent subset of lymphocytes had Fc gamma R and were C3+, and most of these were surface immunoglobulin (slg)-bearing cells. The majority of lymphocytes from this subset were Fc+ C3+, and only a small percentage were Fc+ C3- (in contrast to the findings in blood). IgD and IgM were the predominant classes of findings in blood). IgD and IgM were the predominant classes of immunoglobulin found on the B-lymphocytes. The different preparative techniques did not result in a selective loss of lymphocyte subsets, but collagenase digestion did lead to a loss of expression of the C3 receptor on the lymphocyte surface, which was recoverable when lymphocytes were reincubated at 37 degrees C. No evidence was found for blocking of the C3 receptor by immune complexes with activated complement.

Adult↗
PubMed1982

Wheat gliadin fractions and other cereal antigens reactive with antibodies in the sera of coeliac patients.

The mixed reverse solid phase passive antiglobulin haemadsorption test (MRSPAH) and the enzyme linked immunosorbant assay (ELISA) were found equally sensitive and fitted for the measurement of serum IgG antibodies against alcohol soluble gliadins. Using the ELISA method, three coeliac sera with elevated antibody titres against gliadins and two control sera with low titres were tested for IgG antibodies against the main groups of wheat proteins (acetic acid soluble glutenins, salt soluble albumins and globulins and alcohol soluble gliadins), eight fractions of gliadin and the alcohol soluble proteins of barley, rye, oat, maize and rice. As rice contained little alcohol soluble protein, a test against acid soluble rice proteins was included. In all three patient sera, titres higher than or equal to that for crude gliadin were found for wheat glutenin and for gliadin fractions seven and eight, both containing alpha gliadins. Similar high titres were found when these coeliac sera were tested against rye, barley and oat prolamines. Maize prolamines gave only low titres and no antibodies could be detected against rice proteins, in line with the tolerance of these latter two cereals by patients with coeliac disease. It would appear that sera from coeliac patients react with more than one antigenic fraction of protein in wheat and other cereals. Also sera from two normal persons appeared to have the same spectrum of reactivity against these cereal proteins as did the three sera from coeliac patients. The titres in normal sera were however much lower.

Antigens↗
PubMed1981

A reverse passive haemagglutination test for the detection of respiratory syncytial virus in nasal secretions from infants.

A reverse passive haemagglutination (RPH) test has developed for the detection of respiratory syncytial (RS) virus in nasal secretions, taken from infants with acute respiratory illness. In the final form of the procedure, RS virus was detected in 24 of 25 samples positive for RS virus by tissue culture and/or fluorescence antibody staining and in two samples negative for RS virus by these techniques. The simplicity of the technique and the rapidity with which it may be performed together with its apparently high degree of sensitivity should make RPH useful in the rapid diagnosis of RS virus.

Hemagglutination Tests↗
PubMed1981

MRSPAH: a simple microtitre plate test for rheumatoid factors of different classes.

A simple and inexpensive microtitre plate test (the mixed reverse (solid-phase) passive antiglobulin haemadherence test, or MRSPAH) has been developed for the measurement of antiglobulins (RFS) of different classes. Results obtained for IgM RF by this test have been compared with results of latex and Rose-Waaler (DAT) tests on rheumatoid arthritis (RA) sera. Levels of RFs of IgM, IgG and IgA classes have been measured by MRSPAH using rabbit IgG as antigen in RAs and normal people. 94% of RA sera tested were above the upper limit of normal for IgM and/or IgA RF. There was a considerable overlap between IgG RF levels in RAs and normals, although the means of the two groups were significantly different.

Adult↗
PubMed1981

Lymphocytes infiltrating human breast cancers lack K-cell activity and show low levels of NK-cell activity.

Lymphocytes infiltrating human primary mammary carcinomas lack ADCC and show low levels of natural cytotoxicity. The peripheral blood lymphocytes, however, show a variable but prominent level of cytotoxicity. Lymphocyte preparations from breast tumours, when mixed with autologous blood lymphocytes, significantly suppress their prominent killer- (K- and NK-) cell activities.

Adult↗