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Biomedical subjects

R Jefferis

Publications and source records attributed to R Jefferis.

At least 163 records · Page 9Linked to original sources
PubMed1981

Study of proteolytic removal of Fab delta and Fe delta determinants of lymphocyte membrane IgD using a direct rosette assay.

Proteolysis of lymphocyte surface membrane immunoglobulin (SIg) by trypsin, papain and pronase was investigated. Cleavage in the hinge region resulting in removal of Fab delta was distinguished from removal of the whole SIgD molecule using antisera specific for c delta l and Fc delta. Using the sensitive direct rosette assay SIgD determinants were detected after digestion under conditions previously thought to remove IgD from the membrane. By increasing digestion times is was shown that whilst papain and pronase remove the whole IgD molecule, Fc delta but not Fab delta determinants survive trypsin. The implications of the results for structural differences between membrane and serum IgD and for models of insertion of SIgD into the plasma membrane are discussed.

Epitopes↗
PubMed1981

Properties of monoclonal antibodies to human immunoglobulin kappa and lambda chains.

Hybridomas have been produced from mice immunized with human IgG. Culture supernates were assayed for the presence of antibody-producing cells by passive haemagglutination. Hybridomas producing antibodies to human kappa (kappa) and lambda (lambda) light chains have been cloned and grown as ascitic tumours in BALB/c mice. The antigen-binding characteristics of the monoclonal antibodies, contained in the ascitic fluid, were assessed by haemagglutination inhibition, ELISA and radioimmunoassay systems and by the binding of radiolabelled antigen in analytical flat-bed iso-electric focussing gels. One monoclonal anti-kappa reacted better with free than with combined kappa chains; for another the reverse was true. Antibody fractions separated by DEAE chromatography of ascitic fluids were coupled to ox red cells with chromic chloride and compared with polyclonal antibodies for the detection of cell-surface immunoglobulins.

Animals↗
PubMed1981

Monoclonal antibodies to human IgG: reaction characteristics in the centrifugal analyzer.

We used monoclonal antibodies to human IgG in a kinetic turbidimetric method with a centrifugal analyzer. Results for total IgG with monoclonal and polyclonal reagents correlated well (r = 0.979). Within- and between-batch CVs compared favorably (3.1 and 4.8%, respectively, for polyclonal antisera and 3.5 and 4.0%, respectively, for monoclonal reagents). The monoclonal antibody combination used was shown to be of high titre, with an avidity toward the lower end of the range seen with conventional antisera to IgG. It displayed reaction characteristics similar to those observed with polyclonal antisera, although the time scale of reaction was extended and the effective concentration range was narrowed. Single monoclonal antibodies may not produce complexes of a size exhibiting measurable turbidity when reacted with soluble antigen. However, evidence is presented for the incorporation of such complexes into precipitates produced by other related antigen-antibody systems.

Antibodies, Monoclonal↗
PubMed1980

Quantitation of human total IgG, kappa IgG and lambda IgG in serum using monoclonal antibodies.

Monoclonal antibodies to human IgG have been applied, in parallel with polyclonal antisera, to the routine quantitation of human IgG. Two monoclonal antibodies directed against spatially distinct epitopes have been used in combination to form insoluble complexes exhibiting turbidity. Quantitation was performed using a centrifugal fast analyser and a correlation coefficient of 0.979 was obtained for the two estimations. The technique has been further developed to allow the separate quantitation of kappa IgG and lambda IgG in whole serum.

Antibodies↗
PubMed1980

B lymphocytes in contact dermatitis.

The expression of immunoglobulin on the membrane of peripheral blood lymphocytes of patients with contact dermatitis has been investigated using a sensitive rosette technique. The proportion of such cells in these patients is increased compared to normal values. However, the absolute values obtained are very much lower than has been reported from previous studies. The re-evaluation of immunoglobulin expression is discussed against a background of improved methodology and the established finding that individual lymphocytes may express more than one isotype.

Adolescent↗
PubMed1979

Human immunoglobulin D in colostrum, saliva and amniotic fluid.

An antiserum raised to a partially purified preparation of secretory IgA isolated from human colostrum was shown to contain antibodies directed against human IgD. The inferred presence of IgD in the human colostrum was confirmed and also its association with antibody activity, as demonstrated by the presence of anti-E. coli antibodies. IgD was also shown to be present in whole saliva, parotid saliva and amniotic fluid, but could not be detected in jejunal juice.

Amniotic Fluid↗
PubMed1978

The natural antibody response to E. coli includes antibodies of the IgD class.

Antibodies to E. coli of the IgM, IgG and IgA class are readily demonstrable in normal human serum. Using the sensitive red cell-linked antigen-antiglobulin system, it has been demonstrated that antibodies of the IgD class are also part of this normal response. The IgD antibody titre is low and often could only be demonstrated in partially purified IgD preparations. The availability of purified IgD paraproteins and their Fabdelta and Fcdelta fragments, as well as antisera specific for these fragments, allowed the necessary critical specificity controls to be performed.

Antibodies, Bacterial↗
PubMed1976

A rapid technique for the isolation of human IgD myeloma proteins employing ultragel AcA34.

A relatively rapid technique for the isolation of human IgD myeloma proteins from whole sera is described. It is based on the use of the newly available Ultragel AcA34 gel filtration medium which yields a very substantially purified IgD fraction from whole serum. The absence of IgG from this fraction allows further purification on DEAE cellulose under conditions where the IgD protein is not absorbed but other protein contaminants are retained. The overall yield of IgD protein is estimated at greater than 90% and the technique is particularly applicable to the isolation of IgD from small serum volumes.

Chromatography, Gel↗
PubMed1975

Bisalbuminaemia Birmingham - a new variant in an Indian Family. Characterisation and comparative studies with albumin Kashmir.

Bisalbuminaemia has rarely been reported in races of the Indian subcontinet. The variant described in a native of the Punjab is shown to have a similar electrophoretic mobility to albumin Kashmir but different dye binding properties. The dye binding properties are also different from other albumin variants where such studies have been reported.

Blood Protein Electrophoresis↗
PubMed1975

Isolation of a VHClambda fragment on tryptic digestion of human IgD myeloma proteins.

The tryptic digestion pattern of IgD myeloma proteins is reported. The Fab delta of fragment is shown to be very susceptible to further degradation to yield a novel fragment composed of VH and Clambda domains which are still bound through the interchain disulphide bridge. Reduction results in a change in M.W. from ca. 26,000 to 13,000. The loss of Fd delta of isotypic determinants may be of importance to studies in which membrane bound IgD is detected or measured after release from the cell surface by enzyme digestion.

Epitopes↗