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J W Goding

Publications and source records attributed to J W Goding.

At least 73 records · Page 4Linked to original sources
PubMed1980

Biosynthesis of lymphocyte surface IgD in the mouse.

The synthesis of IgD was studied in mouse spleen cells by using [35S]methionine labeling followed by immunoprecipitation with monoclonal antibody and two-dimensional gel electrophoresis. After a 15-min pulse of [35S]methionine, a relatively basic form (IgD1) of apparent m.w. 59,000 was precipitated. Conversion into more acidic forms of m.w. 63 to 72,000 (IgD2) took place during a chase period of several hours. The acidic form was identical in mobility to that of IgD labeled by surface radioiodination, and was almost completely removed by treatment of intact cells with pronase. Neuraminidase treatment of the surface form (IgD2) produced a form resembling IgD1 in charge, but with no detectable change in m.w. Treatment of IgD1 with endoglycosidase H resulted in a form with an apparent m.w. of 50,000, whereas IgD2 was resistant to this enzyme. Both IgD1 and IgD2 bound to lentil lectin, whereas only IgD2 bound to Ricinus communis hemagglutinin, which binds to terminal galactose residues. These results indicate that IgD is synthesized as an incompletely glycosylated precursor possessing "high mannose" type oligosaccharide moieties, and passes relatively slowly through the cell. Shortly before surface appearance, galactose and sialic acid are added. No specific association with any other labeled protein was observed, and any IgD secretion was below the limits of detectability.

Animals↗
PubMed1980

Detection and characterization of membrane antigens of Toxoplasma gondii.

Toxoplasma gondii tachyzoites were surface radioiodinated by the lactoperoxidase technique, and the solubilized membrane proteins were analyzed by two-dimensional polyacrylamide gel electrophoresis. Four major labeled proteins with apparent m.w. of 43,000, 35,000, 27,000, and 14,000 were detected. None of the radioiodinated proteins bound to concanavalin A-Sepharose. When a panel of eight different fluorescein-conjugated lectins was used in an attempt to characterize further the nature of the cell membrane, none of the lectins bound to intact tachyzoites. Two-dimensional polyacrylamide gel electrophoresis did not reveal any significant differences among three different strains of Toxoplasma. Each of the radioiodinated surface proteins was precipitable by sera from mice chronically infected with the same strain as well as by a series of sera from mice infected with other strains. Sera from humans with acute Toxoplasma infection showed more variability in that some precipitated all labeled proteins whereas others precipitated only two or three of them. Monoclonal antibodies (2G11 and 3E6) prepared by hybridization of spleen cells from Toxoplasma-immune mice with myeloma cells consistently precipitated both the solubilized 35,000 and 14,000 dalton proteins, whereas 1E3 precipitated the 43,000-dalton protein and 1E11 the 27,000-dalton protein.

Animals↗
PubMed1978

Allotypes of IgM and IgD receptors in the mouse: a probe for lymphocyte differentiation.

Antibodies to IgD and IgM are present in many mouse alloantisera made against lymphocytes. Antibodies to IgM are also present in a small minority of conventional antiallotype sera made against pertussis/anti-pertussis complexes. These antibodies reflect different allelic forms of IgD and IgM in different mouse strains, and allowed the mapping of the delta- and mu-chain genes (Ig-5 and Ig-6, respectively) to the heavy-chain complex. The variable portions of IgM and IgD receptors on individual cells bearing both chains are similar or identical. Both receptors show allelic exclusion and come from the same chromosome on individual cells (haplotype exclusion). It is suggested that very early in B lymphocyte differentiation there is a commitment to a given chromosome, and translocation of one copy of a given variable region gene to each heavy-chain gene. Subsequent switches of immunoglobulin class then involve differential gene activation. Immature B cells possess IgM receptors only and mature into cells bearing both IgM and IgD receptors. After activation with antigen, IgD is probably lost. These findings are discussed within the framework of the clonal abortion theory of B-lymphocyte tolerance.

Animals↗
PubMed1978

Use of staphylococcal protein A as an immunological reagent.

This brief review summarises the major uses of staphylococcal protein A in immunology. Protein A is covalently linked to the cell wall of most strains of Staphylococcus aureus, and binds immunoglobulin molecules with high affinity. The principal molecule bo-nd is IgG, although in many cases binding is restricted to certain IgG subclasses. Some IgM and IgA binds in certain species. This property allows rapid, simple and economical methods for the purification and analysis of immunoglobulins, and the fractionation of subclasses which are difficult to separate by other means. Fractionation on protein A affinity columns is a simple and efficient way of separating immunoglobulin F (ab) and F (ab')2 from Fc fragments. Intact staphylococci are useful as a solid phase adsorbent for isolating antigen-antibody complexes, membrane antigens and receptors, and to replace 'second antibody' in radioimmunoassay. Finally, protein A has proven useful for the study of antigens and receptors on the surface of intact cells, and for the detection of antibody-secreting cells. Thus, the use of protein A is now the method of choice for many preparative and analytical purposes in immunology.

Animals↗
PubMed1977

Studies on immune responses to larval cestodes in mice. Increased susceptibility of certain mouse strains and hypothymic mice to Taenia taeniaeformis and analysis of passive transfer of resistance with serum.

Various inbred strains of mice vary markedly in their susceptibility to the larvae of the cestode, Taenia taeniaeformis. Males are generally more susceptible than females and the most susceptible common inbred mouse strains are those which are deficient in C5 and/or C4 components of complement. However, no genetic evidence is yet available to implicate loci controlling complement levels in susceptibility/resistance, and multiple genetic factors appear to be operative. Hypothymic, nu/nu ("nude") mice of the relatively resistant mouse strain, BALB/c, are highly susceptible in that cystic larvae in the liver develop in large numbers and more rapidly than in intact BALB/c.nu/+litter-mates. Cyclophosphamide pretreatment also increases the susceptibility of relatively resistant strains of mice in terms of both the number and size of liver cysts. Hypothymic and intact mice can be protected, absolutely, by an injection of serum from infected intact mice, provided the serum is given to recipient mice close to the time of oral egg administration. The protective activity of immune serum is absorbed totally by staphylococcal protein A-Sepharose columns and can be abolished by treatment of recipients with cobra venom factor. Cyst fluid from established larvae facilitates the activity of subhaemolytic amounts of guinea pig complement in a standard direct PFC assay. The data suggest that complement-fixing antibodies are responsible for inhibition of establishing larvae in mice and that one method of protection for established cystic larvae involves the alteration of host complement activity within the cyst.

Age Factors↗
PubMed1976

Antigen-induced co-capping of IgM and IgD-like receptors on murine B cells.

Double fluorescence studies indicated that most mature lymphocytes of 11-52-wk-old mice possess both IgM and IgD-like surface immunoglobulins, while spleen cells from neonatal mice possess surface IgM only. These molecules cap independently with class-specific antisera, but co-cap when capping is induced by antigen. It is proposed that the two heavy chains on individual lymphocytes possess similar or identical antigen-combining sites.

Age Factors↗
PubMed1976

The chromic chloride method of coupling antigens to erythrocytes: definition of some important parameters.

Factors affecting the efficiency of the chronic cloride method of coupling antigen to erythrocytes were studied using a radioactive tracer. The amount of chromic chloride required for optimal coupling was related to the concentration of protein in the reaction mixture. Coupling was considerably more efficient when the chromic chloride solution was allowed to 'age' prior to use. In the system studied, the addition of piperazine buffer made little difference to the degree of coupling. The reaction was shown to proceed very rapidly. 50% of the final uptake of antigen took place within seconds, and the reaction was essentially complete 5 min after initiation. The importance of adequate mixing during the addition of the chromic chloride solution was emphasised.

Animals↗
PubMed1976

Conjugation of antibodies with fluorochromes: modifications to the standard methods.

A number of modification to the standard procedures for coupling of fluorochromes to antibodies are described. The suggested procedures result in economies of time, labour and materials, and allow the reliable production of high quality conjugates. The modifications include the use of staphylococcal protein A-Sepharose for (a) a simple one-step procedure for preparation of IgG from whole serum, (b) removal of undigested IgG after pepsin treatment, and (c) concentration of dilute solutions of IgG. Many other details of coupling procedures are discussed, and modifications suggested. Optimally coupled antibodies were separated by linear salt gradient elution from DEAESephadex, and the effects of fluorescein and tetramethyl rhodamine on the antibody isoelectric point studied.

Chromatography, Ion Exchange↗
PubMed1976

Genetic polymorphism of IgD-like cell surface immunoglobulin in the mouse.

Lymphocyte surface antigens from spleen cells of several mouse strains were studied by cell surface radioiodination, extraction with detergent incubation with various antisera, and separation of complexes using protein A-containing staphylococci as a solid phase adsorbent. Complexes were then dissociated and analyzed by polyacrylamide gel electrophoresis in the presence of sodium diodecyl sulfate. Using this technique and an alloantiserum prepared in C57BL mice against CBA spleen cells, four distinct specific peaks of radioactivity were found with CBA spleen cells. These corresponded to H-2 and Ia antigens, immunoglobulin light chain, and a heavy chain previously proposed to be the murine homolog of the human delta chain. With the same serum, B10.BR spleen cells revealed only H-2 and Ia antigens, whereas C57BL.Ige (allotype congenic) spleen cells showed only the light chain and "delta" chain peaks. Depletion of immunoglobulin from the surface-iodinated preparations resulted in removal of the light chain and "delta" chain peaks. The tissue distribution and membrane expression of this "delta" chain antigen was then studied by indirect immunofluorescence with various C57BL derived alloantisera and lymphoid cells from C57.Ige allotype congenic mice. Significant numbers of positive cells were found in spleen, lymph nodes, and Peyer's patches, whereas few if any positive were found in bone marrow or thymus. No reaction was found between this molecule and alloantisera to any of the previously described immunoglobulin allotypes. It is proposed that these alloantisera to spleen cells recognise one allelic form of the murine "delta" chain coded for by a gene locus closely linked to the known structural genes for mouse immunoglobulin heavy chains. The designation Ig-5 is proposed for this new immunoglobulin heavy chain locus.

Animals↗