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Biomedical subjects

J A Rudbach

Publications and source records attributed to J A Rudbach.

At least 37 records · Page 2Linked to original sources
PubMed1982

Study of the idiotypy of lipopolysaccharide-specific polyclonal and monoclonal antibodies.

The monoclonal antibodies produced by a variety of hybridomas making antibody specific for E. coli 0113 lipopolysaccharide (LPS) were purified by affinity chromatography and their fine specificity studied. All reacted specifically with the polysaccharide moiety of LPS from E. coli 0113 and from Neisseria lactamica; two reacted with LPS from Pseudomonas aeruginosa and one reacted with LPS from Klebsiella pneumoniae. Polyclonal and monoclonal syngeneic and semi-syngeneic anti-idiotypic antisera were produced to study the idiotypy of LPS-specific monoclonal antibodies which express a complex cross-reactive idiotype (IdX) as well as individual idiotypes. E. coli 0113 LPS-specific antibodies produced by BALB/c mice express this IdX and the kinetics for its expression was examined using mice either primed or hyperimmunized with LPS; idiotypic maturation was observed, but we were unable to detect an auto-anti-idiotypic antibody response. This IdX was expressed on E. coli 0113 LPS-specific antibodies from all strains of mice examined, indicating that its expression is not restricted by genes linked to the IgCH locus.

Animals↗
PubMed1982

Pseudosecondary antibody response to LPS induced by toxins for macrophages.

A single dose of bacterial lipopolysaccharide, administered 21 days after mice had been treated with the macrophage toxins carrageenan, or microparticulate crystalline silica, resulted in a secondarytype antibody response. The phenomenon of pseudosecondary responsiveness was investigated to determine the mechanism for its generation. The results showed that generating a pseudosecondary response was T cell dependent; but except for this, it followed the same kinetic and genetic patterns as a true, two dose of antigens, secondary response. It was concluded that pseudosecondary responsiveness resulted from priming the mice by the consequential effects of the macrophage toxins; thereafter, secondary responsiveness to LPS was generated in a normal manner.

Animals↗
PubMed1982

RIIIS/J mice lack a gene influencing the capacity to make an antibody response to helper T cell-independent antigens.

RIIIS/J mice lack an autosomal dominant gene(s) that has a decisive influence in determining the capacity to make an IgM antibody response to several representative helper T cell-independent antigens; these mice appear to possess functionally active helper T cells because of their ability to make a reasonably good antibody response to SRBC, a helper T cell-dependent antigen. The genetic defect involved cannot be attributed to the absence of B cells capable of giving a mitogenic response to bacterial LPS.

Animals↗
PubMed1982

Modulation of the immune response to lipopolysaccharide.

Mice given a single optimally immunogenic dose (20 micrograms) of bacterial LPS make an antibody response that is characterized by cyclic (oscillatory) patterns. This kinetic pattern is dose as well as mouse strain dependent. LPS can induce a secondary response in BALB/c mice that is also cyclic, although it differs in amplitude as well as periodicity from a primary response. To rule out the involvement of B cell mitogenic activity of LPS in the expression of such cyclic patterns, the responses produced by both C3H/HeN and C3H/HeJ mice to a single injection of LPS were compared; the latter do not give B cell proliferative responses to LPS and also have been reported to give low LPS-specific responses in vivo. Both strains gave an oscillatory kinetic pattern. By contrast, BALB/c nu/nu mice given an optimal immunogenic dose of LPS (2 micrograms) do not present a cyclic immune response. This indicates that mature T cells are required for the generation of an oscillatory anti-LPS response.

Animals↗
PubMed1981

Dissociation of the anti-hapten and anti-carrier responses of mice injected with dinitrophenylated lipopolysaccharide.

The quantitative and qualitative nature of the antibody responses of euthymic (normal, RML) and athymic (nude) mice injected with dinitrophenylated (DNP) lipopolysaccharide (LPS) was evaluated. Antibody responses to both the haptenic (DNP) and carrier (LPS) determinants were measured. On a quantitative basis, RML and nude mice stimulated with DNP-LPS produced only primary anti-DNP responses, whereas both primary and secondary anti-LPS responses were elicited by this conjugate. The failure of DNP-LPS to trigger secondary anti-DNP responses was not dependent on the amount of DNP-LPS given in the primary or secondary doses and could not be overcome by repeated injections of DNP-LPS. Also, the anti-DNP responses of RML mice injected repeatedly with DNP-LPS were restricted to immunoglobulin M antibodies whereas both immunoglobulin M and G anti-LPS responses were elicited. Nude mice also produced immunoglobulin G antibodies to the LPS determinants. These data showed a dissociation of the anti-hapten and anti-carrier antibody responses and suggested that different immunological signals were functioning in the respective anti-DNP and anti-LPS responses.

Animals↗
PubMed1977

Immunological responses of mice to lipopolysaccharide: lack of secondary responsiveness by C3H/HeJ mice.

Mice of the C3H/HeJ strain, which were unresponsive to the biological effects of bacterial lipopolysaccharide (LPS), could not be induced to make specific secondary immunological responses to LPS; they responded to two doses of LPS with a primary response. This lack of secondary responsiveness by C3H/HeJ mice was due to a defect in a single, autosomal, dominant gene. Thus, further evidence was provided that an intact second immunological signal and responsiveness thereto were required to trigger secondary antibody responses in primed animals.

Animals↗
PubMed1976

Preparation and properties of a national reference endotoxin.

A large pool of refined endotoxin was prepared from Escherichia coli O113 by extraction with hot acqueous phenol. It was characterized chemically and biologically and will be available for a reference standard designated as reference endotoxin EC.

Animals↗
PubMed1976

Antibody responses of mice to alkaline detoxifield lipopolysaccharide.

The antibody responses of outbred normal mice and nude mice injected with alkaline detoxified lipopolysaccharide (Alk-LPS) were measured. In some cases the antibody against lipopolysaccharide (LPS) and native protoplasmic polysaccharide (NPP). The kinetics of the primary responses to Alk-LPS and NPP were similar, whereas LPS stimulated a more rapid appearance of antibodies in the primary responses. Alk-LPS stimulated only primary antibody responses in both types of mice and sensitized nude mice for secondary responses which could be triggered with LPS. However, secondary antibody responses could not be triggered in normal mice primed with Alk-LPS. These data suggested that, on a functional basis, Alk-LPS possessed the specific antigenic signal associated with LPS antigens but lack the second nonspecific mitogenic signal dependent on the lipid A portion of LPS.

Alkalies↗
PubMed1975

Radioimmunoassay for quantifying antibody to N. Gonorrhoeae in human sera.

A radioimmunoassay has been developed for the serodiagnosis of gonorrhoea. When 382 human sera from acutely infected and well documented control subjects were assayed by this procedure, 90% were diagnosed correctly, 5% were diagnosed incorrectly, and in 5% the results were indecisive.

Antibodies, Anti-Idiotypic↗
PubMed1974

Immunological responses of mice to native protoplasmic polysaccharide and lipopolysaccharide: functional separation of the two signals required to stimulate a secondary antibody response.

Functional separation of the two signals involved in stimulating immunological responses was achieved through the judicious use of two natural bacterial antigens. Native protoplasmic polysaccharide (NPP) extracted from Escherichia coli was immunochemically identical to the lipopolysaccharide (LPS) extracted from the same organism. However, NPP was not endotoxic, not mitogenic, did not fix complement, and was immunologically independent of T cells. The NPP, which appeared to contain only the antigenic signal, could induce a primary antibody response in mice and could sensitize mice for a secondary response. However, the antigenic signal contained in NPP was insufficient to trigger a secondary response in mice primed with either NPP or LPS. LPS, containing both the antigenic and second signals, was required to trigger a secondary response in primed mice.

Animals↗