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Biomedical subjects

R R Coombs

Publications and source records attributed to R R Coombs.

At least 55 records · Page 3Linked to original sources
PubMed1985

Detection and quantitation of rotavirus using monoclonal antibody coupled red blood cells: comparison with ELISA.

A total of 125 faecal extracts from infants were tested by reverse passive haemagglutination (RPH) using red cells coated with a monoclonal antibody against the major group-specific rotavirus antigen (VP 6). Results were compared with those obtained using a rabbit anti-rotavirus capture, guinea pig anti-rotavirus detector-based ELISA. The specificity of the assay was confirmed by use of 'normal' immunoglobulin coupled red cells and by inhibition with rabbit antiserum. The antibody-coated red cells could be stabilised by treatment with glutaraldehyde and subsequent freeze-drying with no detectable loss of activity even after storage at 45 degrees C for 4 wk. Good correlation was obtained between RPH and ELISA. Purified bovine rotavirus could be detected by RPH down to approximately 10(5) particles in a 25 microliters vol. Similar results were obtained with polyclonal antibody coupled cells and an ELISA using monoclonal antibody. Experiments using subgroup-specific monoclonal antibodies indicated the feasibility of rapid subgroup determination.

Animals↗
PubMed1985

The mechanical properties of human flexor tendons in relation to artificial tendons.

The continuation of an unacceptable failure rate with tendon repair or grafting procedures, largely due to adhesions, suggested that an artificial flexor tendon could be an attractive alternative. A literature search found no published data of the mechanical properties of fresh human finger flexor tendons, so a study of the strength and extensibility of 153 tendons was carried out. The bone insertion strength of twenty middle finger tendons was also examined. The results showed that an artificial tendon should have a strength of approximately 1500N, and that it should extend 13% at that load, an elongation of 26mm for a tendon 200mm long. The insertion strength was less than a half of the tendon strength. This data will allow an artificial flexor tendon to be designed with sufficient strength and the correct elastic properties to allow its function to integrate reliably with natural tendons in adjacent fingers.

Aged↗
PubMed1985

Early rheumatoid-like synovial lesions in rabbits drinking cow's milk. I. Joint pathology.

Rheumatoid-like lesions developed in 9 of 25 (36%) Old English rabbits drinking cow's milk for 12 weeks. The incidence of lesions in male and female animals was similar. The majority of rabbits drinking cow's milk developed increased numbers of nucleated cells and raised percentages of T lymphocytes in their synovial fluids, compared to control rabbits. The cell counts and T cell percentages correlated with the severity of the histological lesions. No evidence of glomerulonephritis was observed in any of the experimental animals.

Animals↗
PubMed1985

Early rheumatoid-like synovial lesions in rabbits drinking cow's milk. II. Antibody responses to bovine serum proteins.

Thirty-six percent of Old English rabbits fed pasteurized cow's milk developed early rheumatoid-like synovial lesions. All rabbits drinking milk developed high titres of serum and synovial fluid Clq-binding activity. This has been shown to be due to specific antibody to Clq, produced in response to Clq in cow's milk. In addition, these rabbits responded to other bovine proteins present in cow's milk, including conglutinin, beta-lactoglobulin and IgG. There was no correlation between serum or synovial fluid titres of antibody to bovine milk proteins and synovial lesions.

Animals↗
PubMed1985

Fusidic acid in orthopaedic infections due to coagulase-negative staphylococci.

Twenty orthopaedic in-patients who developed an acute infection due to coagulase-negative staphylococci, and which was associated with a foreign body in 11 cases, were treated with fusidic acid. All patients were given oral medication, except for 1 child with acute osteomyelitis who was treated intravenously for the first 7 days. The mean daily dose was 21 mg/kg and the mean duration of treatment 20 days. Fusidic acid was given alone in 5 patients and concurrently with another antibiotic in the other 15 patients. All patients responded satisfactorily with resolution of the relevant signs and symptoms, although 1 patient relapsed subsequently. Mild side-effects were observed in 3 patients.

Administration, Oral↗
PubMed1984

Discrimination between innate and cytophilic immunoglobulin on human peripheral blood lymphocytes: analysis by the direct antiglobulin rosette-forming reaction.

Bovine red blood cells linked to polyclonal or monoclonal anti-immunoglobulin antibodies are used in the direct antiglobulin rosetting reaction to detect surface-Ig on human lymphocytes. The sensitivity of this test is markedly increased by pretreating the red cells with trypsin. Enzyme-treated red cells, coupled to anti-human Fab or anti-light chain antibodies, react not only with innate Ig on B lymphocytes but also with smaller amounts of passively adsorbed, cytophilic Ig on up to 25% of freshly prepared peripheral blood (non-B) lymphocytes. In contrast, trypsinized red cells carrying anti-Ig isotype-specific antibodies react exclusively with B cell surface-Ig. Cytophilic Ig is abnormally firmly bound to lymphocytes separated on Ficoll-Hypaque at 20 degrees C or below, and is released very slowly during 3 h or more at 37 degrees C in vitro. Lymphocytes are free of detectable cytophilic Ig when isolated on Ficoll-Hypaque at 37 degrees C, and very little Ig is retained by non-B cells in suspensions purified on Percoll which, unlike Ficoll, does not increase Ig binding affinity. These lymphocyte separation procedures are recommended as a preliminary to B cell assays by sensitive antiglobulin techniques.

Agglutination↗
PubMed1984

Latent anaphylactic sensitisation of infants of low birth weight to cows' milk proteins.

Latent systemic anaphylactic sensitisation to cows' milk was assessed in 61 preterm infants who were randomly assigned to receive either a special formula for preterm infants based on cows' milk or banked breast milk or one or other of these as a supplement to maternal milk. A single sample of venous blood was taken near to the time of discharge from the neonatal intensive care unit, and the histamine release by blood basophils in response to in vitro challenge with cows' milk and anti-IgE was measured. Compared with the blood from infants fed on human milk, that from infants fed on preterm formula showed a significant increase in histamine release to challenge with cows' milk, the response being greater in blood from infants of lower birth weight and gestational age. A smaller but significant increase in blood histamine release with anti-IgE challenge was observed in the group fed on preterm formula. Infants of low birth weight fed on preterm formula based on cows' milk may develop latent systemic sensitisation more rapidly than infants born at term. The clinical importance of this requires further investigation.

Anaphylaxis↗
PubMed1984

Red cell-labelled monoclonal antibodies for assay of human chorionic gonadotropin and luteinising hormone by reverse passive haemagglutination.

The assay of human chorionic gonadotropin and luteinising hormone by reverse passive haemagglutination reaction, using monoclonal antibodies coupled to red cells, is described. Quantitation is achieved by end-point determination for serial dilutions of standard or sample, the haemagglutination reaction being observed after settling under gravity for 90 min. Red cell-labelled antibodies were stabilised with glutaraldehyde without loss of sensitivity and allowing long term storage. Various antibody combinations were assessed, and the best combination under optimum conditions gave a positive haemagglutination reaction down to 0.2 ng/ml with HCG.

Antibodies, Monoclonal↗
PubMed1984

Detection of monoclonal antibodies against cell surface antigens: the use of antiglobulins coupled to red blood cells.

An antiglobulin-coupled red cell assay is described for screening monoclonal antibodies against cell surface antigens. A monoclonal antibody specific for rat immunoglobulin kappa chains was coupled to red blood cells and used to detect binding of rat monoclonal antibodies to cells attached to the wells of microtitre plates. The method was found to be simpler and more rapid than the alternative enzyme-linked binding assay and useful for rapid screening and selection of antibodies for use as differentiation markers of human and mouse haemopoietic cells.

Animals↗
PubMed1984

The use of monoclonal antibodies to differentiate isolates of herpes simplex types 1 and 2 by neutralisation and reverse passive haemagglutination tests.

Monoclonal antibodies specific for herpes simplex type 1 or type 2 were used in reverse passive haemagglutination tests or infectivity neutralisation tests to serotype 100 isolates of herpes simplex virus (HSV). All isolates were independently serotyped by measuring their sensitivity to bromovinyl deoxyuridine. Reverse passive haemagglutination tests with type-specific antibodies directed against the HSV glycoprotein D and major DNA binding protein gave results in perfect agreement with the results of drug-sensitivity measurement. A single isolate behaved anomalously in the neutralisation test with a type 1-specific antibody directed against glycoprotein A/B. Restriction-enzyme analysis of virus DNA suggests that this isolate contains a variant glycoprotein A/B. The two methods used for serotyping proved very sensitive, giving adequate results with samples containing as little as 100 plaque forming units (pfu) of HSV. The reverse passive haemagglutination test has the additional advantages of speed and simplicity.

Antibodies, Monoclonal↗
PubMed1984

Histological diagnosis of carcinoma of the parathyroid gland.

During the period 1950-81, 678 cases of primary hyperparathyroidism were surgically treated at University College Hospital, London. The causes were a single adenoma in 575, two adenomas in 25, carcinoma in 20 (two of which had coexistent adenomas), chief cell hyperplasia in 56, and water clear cell hyperplasia in two. Histological diagnosis is not difficult except in some cases of carcinoma and in a few in which differentiation between recurrent hyperplasia and recurrent carcinoma is exceptionally difficult. In this paper we review all the cases of primary carcinoma of the parathyroid seen during this period to define those pathological features of value in the diagnosis.

Adenoma↗
PubMed1984

Immediate hypersensitivity reactions to cow milk proteins in isolated epithelium from ileum of milk-drinking guinea-pigs: comparisons with colonic epithelia.

The epithelium lining the ileum has been isolated and studied in vitro under short-circuit conditions. Tissues were obtained from guinea-pigs fed cow milk. When challenged with beta-lactoglobulin on either the apical or basolateral side, a transient, inward flowing current was recorded. This reaction did not occur with tissues from non-milk drinking animals. Casein and alpha-lactalbumin, in contrast to beta-lactoglobulin, produced only minor effects while bovine serum albumin and bovine gamma-globulin were without effect. The effect with beta-lactoglobulin was associated with overall fluid secretion in the basolateral to apical direction, although the ions responsible for carrying the current have not been identified. Possible mediators of the response to beta-lactoglobulin have been investigated. Throughout the responses of the ileum have been compared with those in the colon. The differences between the two tissues is striking. The relevance of the model to mechanisms of food intolerance is discussed.

Animals↗
PubMed1984

Allergenicity of food proteins and its possible modification.

All food proteins, taken via the oral route, are likely to be allergenic to some degree, but this usually leads to no untoward effects. Over the last decade excellent immunoassay methods have been developed that are suitable for measuring anti-food protein antibodies of different isotypes. General systemic and local tissue sensitivity to food antigens may also be measured by appropriate methods. All the circumstances (e.g., amount of ingestant, conditions in the gut, selective immunodeficiencies, gut permeability and genetic factors) determining heightened allergic responses are not yet fully understood. Allergic disease "caused by" food allergens may take on a variety of forms depending on the organ(s) bearing the brunt of the reactions: the gut itself, the skin, the lungs, joints or the entire body. Factors governing the severity of disease include the level of sensitization, the antibody isotype, the type of allergic sensitivity and again the extent of antigen absorption from the gut. Among the foods discussed are cow's milk and other formulae based on soya, chicken meat and hydrolysed casein for infant feeding. A test in guinea pigs to screen for potential oral sensitizing capacity of infant feeds is discussed, as is the effect of heat treatment of milks to reduce their sensitizing capacity. The antigenicity of cereal proteins per os in human adults and in laboratory animals is also dealt with.

Anaphylaxis↗
PubMed1983

Glutaraldehyde stabilisation of antibody-linked erythrocytes for use in reverse passive and related haemagglutination assays.

A simple method for stabilising antibody-linked red blood cells by the addition of low concentrations of glutaraldehyde is described. Fresh and stabilised reagent-linked cells were shown to compare favourably in reverse passive haemagglutination for the measurement of human immunoglobulin isotypes, G, A and M and for the detection of respiratory syncytial and herpes simplex viruses. Stabilised cells were also used to detect antibodies to bacteria and to a soluble antigen adsorbed to a solid phase by mixed haemagglutination reactions.

Animals↗
PubMed1983

The demonstration of sIg, MHC and T cell antigens and Fc receptors on the lymphocyte surface by anti-globulin rosetting reactions: some technical considerations.

The previously shown marked difference in sensitivity of antiglobulin rosette formation and immunofluorescence was confirmed in detection of varying amounts of anti-Ig bound to B cells. The direct and indirect rosette method revealed twice the number of sIg+ cells shown by direct immunofluorescence (DIF), and at least an order of magnitude more antibody on the cell surface is necessary to detect the conventional B cells (shown by DIF) by indirect immunofluorescence compared with indirect antiglobulin (IARR) rosette formation. Variants of the sensitive IARR test were developed to reveal general lymphocyte, MHC class I and class II and T cell-specific antigens and Fc receptors using xenogeneic or allogeneic reagents. Sensitive indicator cells were used which form almost no rosettes with unsensitized lymphocytes although coated with IgG which would otherwise bind to the Fc receptor. The suggestion that chromic chloride treatment inactivates the relevant Fc determinants was supported by experiments showing the failure of IgG antibody-sensitized bovine RBC (standard Fc indicator cells) to form rosettes after treatment with chromic chloride.

Animals↗
PubMed1983

The use of monoclonal antibodies in (reverse) passive haemagglutination tests for herpes simplex virus antigens and antibodies.

Three monoclonal antibodies against herpes simplex virus type 2 have been tested for their suitability as reagents in reverse passive haemagglutination. Two of these antibodies with specificity for virus glycoprotein D, when linked to red blood cells, were able to capture antigens without being agglutinated, but addition of immune serum subsequently led to agglutination. Haemagglutination using these monoclonal antibody-linked, antigen-captured red cells was readily applicable to testing human sera for antibodies to herpes simplex virus and the titres obtained correlated with those from virus plaque neutralisation tests. The procedure has been termed "Specific Antigen Capture Passive Haemagglutination." A further monoclonal antibody with specificity for the major DNA-binding protein of type 2 herpes virus-infected cells (a nonstructural protein) showed conventional reverse passive haemagglutination when linked to red blood cells and was specific for type 2 herpes simplex virus. The nature and potential uses of these simple reverse passive haemagglutination procedures using monoclonal antibody reagents are discussed.

Antibodies, Monoclonal↗
PubMed1983

Latent anaphylactic sensitivity of infants to cow's milk proteins. Histamine release from blood basophils.

Approximately 25% of infants tested released greater than 9% of their blood basophil histamine content in the presence of cow's milk proteins, indicating a degree or level of latent anaphylactic sensitivity to these allergens. Approximately 10% of infants show a considerably higher level of sensitivity (14-63% histamine release). These findings fulfil an essential tenet of the modified anaphylactic hypothesis for cot-death.

Anaphylaxis↗