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H Fiebig

Publications and source records attributed to H Fiebig.

89 records · Page 5Linked to original sources
PubMed1979

[Regulations of IgM immune response. IV. Effect of the hapten: carrier ratio and the nature of the carrier on the intrinsic and functional affinity of carp DNP-antibodies].

Carp anti-DNP antibodies were raised by various DNP-carrier conjugates. Their intrinsic affinity (K0) to monovalent E-DNP-L-lysine and functional affinity (DF) for binding to the multivalent DNP-T4 bacteriophages were determined. The functional affinity of antibodies elicited by T-cell-dependent DMPn-HSA (n = 3, 15, 33) is relatively high (KF):1010-1012 M-1). These KF values increase more than K0 during the immune response. The functional affinity is dependent on the molar KNP: HSA ratio. The mediate coupled DMP15-HSA elicits antibodies with the highest functional affinity. Carps immunized with T-cell-independent DNP-conjugates synthesize antibodies which have similar K0 as the antibodies elicited with DNP-HSA. However, the KF-values are in the range from 107 to 1010 M-1 only. The KF of antibodies raised with DNP-BA are 103-104 fold, those of DNP-S III and DNP-Ficoll elicited are only 4 . 101 to 4,7 . 102 fold higher than their corresponding K0-values. This means that these antibodies are not very effective in binding the multivalent DNP-T4. Specifically purified antibodies have also such low functional affinities. These strong differences in the functional affinity of carp DNP-antibodies elicited by T-cell dependent and independent DNP-conjugates are discussed with regard to stimulation of different B-cell subpopulations.

Animals↗
PubMed1979

Studies on the regulation of igm immune response. VII. changes in the affinity of antibodies and cell receptors after immunization with the T-cell independent antigen DNP-Ficoll.

A/J-mice immunized by a single injection with DNP21-Ficoll respond on the humoral level exclusively with IgM antibodies. The intrinsic association constants (K0) of IgM anti-DNP to monovalent hapten E-DNP-L-lysine are within the range of 105-106 M-1 and do not change significantly during the immune response. On the other hand, the functional association constants (KF) of pentameric IgM to multivalent DNP-T4 bacteriophage increase from 1010 M-1 at 3rd day up to 1012 M-1 at 8th day. Subsequently, a decrease of KF to 1011 M-1 can be observed. This rise and fall of the affinity of IgM antibodies of multivalent DNP-conjugate can be detected at the cellular level also by inhibition of plaque formation. The concentration of DNP15-BSA needed for 50% inhibition of plaque formation (I50) decreases from second day to 8 th day by 4 orders, which represents a strong increase of functional affinity. In contrast, the I50 of E-DNP-L-lysine slightly decreases only until day 4 and does not change until day 21. the inhibition of rosette formation by mono- and multivalent ligands was used to study the affinity of lymphocyte receptors. In the course of immunization antigen-binding cells carrying receptors with increasingly higher affinity for multivalent DNP-conjugates occur. These results are discussed with regard to the importance of functional affinity of lymphocyte receptors for the antigen-driven selection of high affinity anti-DNP-cell clones producing IgM antibodies.

Animals↗
PubMed1979

[Studies on the control of IgM-antibody synthesis V. Affinity of anti-DNP antibodies in carps immunized with DNP-ficoll (author's transl)].

The dynamics of affinity of anti-DNP antibodies of carps immunized with T cell independent DNP-Ficoll was studied during the immune response. The intrinsic affinity (KO) of antibodies to monovalent epsilon-DNP-lysine is 10(5)--10(6)M-1 and does not change significantly in course of the immunisation. The affinity of tetrameric IgM antibodies to multivalent DNP-T4 conjugate is only 10(2)--10(3)-fold greater than to monovalent hapten, contrary to about 10(6)-fold higher values following immunisation with T cell-dependent antigens. The functional affinity (KF) increases during immune response slightly. KO and KF or antibodies are dependent on antigen dose. High antigen doses elicite antibodies with higher affinity.

Animals↗
PubMed1977

[Cell surface immunoglobulin of carp lymphocytes (Cyprinus carpio L.)].

Molecular size and polypeptide chain composition of cell membrane immunoglobulin (mIg) on lymphocytes of carp were studied using lactopreoxidase-catalysed surface radioiodination and SDS-polyacrylamide gel electrophoresis. Carp lymphocytes prepared from pronephros, blood and thymus carry mIgM in relatively high quantity. That means about 5-10% of the radiolabelled macromolecular cell surface material precipitates as IgM. Cell surface IgM on carp lymphocytes is present as monomeric IgM (m.w. 220000-260000) and HL subunit (m.w. 110000). There are differences among molecular weights of mIg monomers of pronephric lymphocytes (m.w. 220000) and thymocytes (m.w. 260000), whereas blood lymphocytes show both components. Following reduction and alkylation H and L chains were observed. Additional thymocytic mIg possesses two unidentified components with m.w. 35000-40000 and 110000.

Animals↗
PubMed1977

[Regulation of the IgM immune response. I. Changes in the affinity of carp anti-DNP-antibodies during immunization depending on the antigen dose].

The affinities of anti-DNP-antibodies (IgM) of carp, immunized with different doses of dinitrophenylated human serum albumin in complete Freund's adjuvant, were determined by a modified Farr-technique using the hapten epsilon-DNP-L-Lysine. Very low affinity antibodies were formed in the early immune response (Ko = 0.2 - 1.0-10(5) M-1). A progressive increase in IgM antibody affinity occurred during the immune reaction. After immunization with low doses of antigen (0.01 and 0.1 mg) the affinity increased up to four weeks (Ko = 3.2 and 9.1-10(5) M-1) and decreased in the subsequent three weeks (K = 0.8 and 1.2-10(5) M-1). Following immunization with a higher dose of antigen (1 and 10 mg), the affinity increased up to seven weeks (Ko = 4.9 and 11.9-10(5) M-1). The highest antibody concentration in all groups were observed at the maximum of affinity.

Animals↗
PubMed1976

[Modification of the immune reaction by antigen-immunosuppressive-agent conjugates. II. Immunogenicity of antigen-immunosuppressive-agent conjugates].

The maintenance of specific immunogenicity of carrier proteins is a necessary condition for the successful use of antigen-immunosuppressive agent-conjugates (AIC) for an antigen specific suppression of the immune response. The experimental results indicate that, in spite of the binding of 6-mercaptopurine (6-MP) and toluyl (T) to bovine gamma globulin (BGG) and human serum albumin (HSA), the carrier specific immunogenicity is not significantly altered. The intradermal application of 6-MP-BGG and T-BGG emulsified with complete Freund's adjuvant in guinea pigs results, in all cases, in a well detectable anti BGG hemagglutination and precipitation titer. This kind of immunization leads also to a formation of anti 6-mercaptopurine and anti new antigen determinants (NAD's) antibodies.

Animals↗
PubMed1976

[Modification of the immune reaction by antigen-immunosuppressive agent-conjugates. III. Physiocochemical, antigenic and functional properties of 6-mercaptopurine coupled carrier proteins].

6-mercaptopurine (MP) conjugates of bovine gamma globulin (BGG) and human serum albumin (HSA) with increasing numbers of MP-groups per protein molecule were prepared and some physicochemical and antigenic properties studied. The electrophoretic mobility increased proportionally to the degree of substitution. In the same manner the formation of high molecular weight aggregates increased. A loss of BGG and HSA specific determinants was observed too. The physicochemical and antigenic properties of these antigen-suppressive agent-conjugates with low and medium coupling degree (to MP26-BGG and MP20-HSA) were similar to the unmodified antigens. The affinity of rabbit anti-DNP-antibodies decreased from K0 = 1,4 - 10(6) M-1 of the unmodified antibodies to 6,5 - 10(5), 3,6 - 10(5) and 3,4 - 10(5) M-1 of the antibodies conjugated with 15, 21 and 29 MP-groups per antibody molecule. The precipitation capacity of the MP-conjugated antibodies decreased to 89, 85 and 61% for the same coupling ratios. These results suggest that the upper limit of the coupling ratio of the antibodies is 20 to 1.

Animals↗
PubMed1975

[Structural and immunochemical studies on the immunoglobulin of carp (Cyprinus carpio L.). III. Valence and affinity of antidinitrophenyl-antibodies].

Carps were immunized with DNP conjugated to human serum albumin, bovine gamma globulin and Brucella abortus. The antibodies were isolated by immunoadsorption. The intrinsic average association constant (Ko) of the antibodies was determined by equilibrium dialysis and ammonium sulphate precipitation employing the monovalent hapten tritiated epsilon-DNP-L-lysine. The tetrameric carp IgM possesses four measurable combining sites per molecule. The affinity (Ko) of the isolated antibodies varied from less than 10(4) M-1 to 2,5-10(5) M-1. The highest determined affinity in the whole serum was 4,4-10(5) M-1. The affinity of antibodies, which was determined in the whole serum was 1,1--1,45 times higher than the affinity of specifically purified antibodies. The selective influence of the antibody isolation procedure was unimportant. The affinity of these IgM antibodies increased twice during the first stage following immunization and did not change significantly over a 25-month period.

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