Fine Specificity Pattern Research Articles

Idiotypic Analysis of Anti-GAT Antibodies

Abstract The specificity and distribution of an interspecties cross-reactive idiotype are described in 13 inbred strains of rats. This interspecies cross-reactive idiotype was defined by the ability of rat anti-GAT antisera to inhibit the binding of the murine CGAT idiotype to the corresponding anti-CGAT idiotypic antiserum. High levels of the interspecies cross-reactive idiotype were detected in 9 of 13 rat strains; all individuals of these 9 strains produced detectable levels of the idiotype. The idiotype was always associated with anti-GAT antibodies. Following immunization with GAT, all individuals of the other four rat strains produced anti-GAT antibodies with low or undetectable levels of the interspecies cross-reactive idiotype, although the anti-GAT antibodies from these latter strains had fine specificity patterns similar to that of the idiotype-positive strains. Immunization of the low idiotype producer LEW and F344 strains with GAT conjugated to the highly immunogenic fowl γ-globulin carrier also failed to induce detectable levels of the interspecies cross-reactive idiotype. Prolonged immunization schedules were used to determine the persistence of this idiotype in rats; the data demonstrated that the ability (or inability) to produce the interspecies cross-reactive idiotype is a stable trait and lasts over 174 days. There was no apparent association of the idiotypic marker with the known rat immunoglobulin heavy and light chain allotypic specificities. Finally, the rat interspecies idiotype is cross-reactive, but not identical with the mouse CGAT idiotype.

Hapten-specific T-cell responses to 4-hydroxy-3-nitrophenyl acetyl. I. Genetic control of delayed-type hypersensitivity by VH and I-A-region genes.

Hapten-specific delayed-type hypersensitivity (DTH) was induced in several strains of mice. (4-hydroxy-3-nitrophenyl)acetyl-bovine gamma globulin (NP-BGG)-primed mice which did not bear the Ig1b heavy-chain linkage group made a NP-specific DTH response when challenged with NP bovine serum albumin (BSA) and failed to respond to challenge with (4-hydroxy-5-iodo-3-nitrophenyl)acetyl-bovine serum albumin (NIP-BSA). Strains of NP-BGG-primed mice bearing the Ig1b allotype, including SJL, responded to challenges of either NP-BSA or NIP-BSA. F1 hybrids between a cross-reactive strain, C57BL/6, and two other noncross-reactive strains were cross-reactive. Genetic mapping of the NIP-cross-reactive DTH response localized the trait to the VH-region of the Ig1b heavy-chain linkage group. The fine-specificity pattern of the T-cell anti-NP response, and the genetic mapping of this trait, were analogous to the reported fine specificity and mapping data of the humoral heteroclitic anti-NP response. Adoptive transfer studies on the ability to transfer NP-specific DTH between various strain combinations showed that the T-cell donors and the recipient must have homology for at least the I-A subregion. Whenever NP-specific reactivity was transferred from a strain which cross-reactively responded to NIP, the recipient also responded to both NP and NIP. The implications of the control of NP-primed DTH-reactive populations of T cells by two distinct genetic regions, VH and H-2, were discussed.

Fine specificity of antibodies to poly(Glu60Ala30Tyr10) produced by hybrid cell lines.

The polyethylene glycol-mediated cell fusion technique has been used to analyze the diversity of the antibody response to the terpolymer poly(Glu60Ala30Tyr10)(GAT). Nine stable clones (all producing IgM K anti-GAT antibodies) were isolated from a fusion between P3-X63-Ag8 myeloma cells and spleen cells from a DBA/2 mouse sensitized to GAT 5 days earlier. Seven other clones (producing IgG K anti-GAT antibodies) were derived from another fusion between NSI myeloma cells and spleen cells of (C57BL/6 X DBA/2)F1 hybrid mice hyperimmunized with GAT. These 16 anti-GAT antibodies were grouped according to their pattern of reactivity with GAT and the two related polymers of poly(Glu60Ala40) (GA) and poly(GLU50Tyr50) (GT). Two monoclonal anti-GAT antibodies (IgM F9-102.2 and IgG F17-148.3) demonstrated crossreactivity with GA but failed to crossreact with GT determinants. In contrast, the remaining 14 hybridoma antibodies demonstrated preferential reactivity with GAT but also exhibited crossreactive binding to GT and in some cases GA. There was a correlation between the fine specificity pattern and the presence of a common anti-GAT idiotype on these antibodies. Thus, the hybridoma anti-GAT antibodies which reacted with GT shared crossreactive idiotypic determinants (CGAT) present in mouse anti-GAT immune sera. In contrast, the monoclonal F9-102.2 and F17-148.3 antibodies that failed to bind to GT lacked the major CGAT idiotypic determinants.

Idiotypic Analysis of Anti-Gat Antibodies

Abstract The humoral response to poly-(L-glutamic acid60, L-alanine30, L-tyrosine10), GAT, in mice is further characterized by both idiotype and fine specificity analyses. The common idiotype on murine anti-GAT antibodies (CGAT) was identified in anti-GAT antisera from seven additional strains of mice. These data confirm that the CGAT idiotype can be induced in all inbred strains of mice. Using a partially inbred strain of mice selected for their ability to respond to poly-(L-glutamic acid50, L-tyrosine50), GT, we demonstrated that the GT copolymer is capable of inducing antibodies that express the CGAT idiotype. In contrast, antisera directed against poly-(L-glutamic acid60, L-alanine40), GA, bind GAT but lack CGAT idiotype. These results indicate that GAT molecules contain determinants either similar or identical to those on GT molecules, which are responsible for the induction of CGAT idiotypic antibodies. We also demonstrated that both GAT responder and nonresponder strains of mice can produce anti-GAT antibodies with similar fine specificity patterns and CGAT idiotype. In addition, we demonstrate that antibodies of the IgM, IgG1 and IgG2 immunoglobulin classes express the CGAT idiotype.

Analysis of the repertoire of anti-NP antibodies in C57BL/6 mice by cell fusion. I. Characterization of antibody families in the primary and hyperimmune response.

AbstractSpleen cells from C57BL/6 mice sensitized to the hapten (4‐hydroxy‐3‐nitrophenyl)acetyl (NP) were hybridized with myeloma cells, and a variety of hybrid cell lines was isolated which secreted homogeneous anti‐NP antibodies. The antibodies were purified by affinity chromatography and their chain composition, affinity and fine specificity were determined. All antibodies recovered from the primary immune response carried λ light and μ or γ1 heavy chains. Their variable portions were nonidentical but similar in terms of hapten‐binding specificity with a higher affinity for the cross‐reacting haptens (4‐hydroxy‐3,5‐dinitro‐phenyl)acetyl (NNP) and (4‐hydroxy‐5‐iodo‐3‐nitro‐phenyl)acetyl (NIP) than for the homologous hapten NP. This heteroclitic property as well as the presence of λ, μ and γ1 chains are characteristic for primary anti‐NP sera of C57BL/6 mice.In contrast, four families of anti‐NP antibodies, each with a characteristic fine specificity pattern, were found among the hybrid cell antibodies derived from the hyperimmune anti‐NP response. The antibodies of one of these families were related to the antibodies recovered from the primary immune response in that they were heteroclitic and carried λ light chains. All members of the other groups expressed k chains and were nonheteroclitic.The finding of well‐defined antibody families in this system and the isolation of their members enable us to approach the problem of V gene expression and diversification in a new way.

Strain differences in the fine specificity of mouse anti-hapten antibodies.

AbstractMice of six strains were immunized with (4‐hydroxy‐3‐nitrophenyl)acetyl (NP) groups coupled to chicken globulin. The fine specificities of these antibodies were characterized by estimating relative affinities for related compounds, (4‐hydroxy‐3, 5‐dinitro‐phenyl)acetyl (NNP), (5‐bromo‐4‐hydroxy‐3‐nitrophenyl)acetyl (NBrP) and (4‐hydroxy‐5‐iodo‐3‐nitrophenyl)acetyl (NIP) groups. These measurements were carried out on both serum and single plaque‐forming cell antibodies. At least three patterns of fine specificity could be recognized among these strains.C57BL/6 produced 7 S (IgG) anti‐NP that consistently had 3–10 times higher affinity for NIP than for NP, and higher affinity for NNP and NBrP than for NP (heteroclitic). By doing affinity measurements on serum and plaque‐forming cell antibodies, we could demonstrate that the majority of the 7 S (IgG) anti‐NP produced by C57BL/6 mice was heteroclitic at both early and later stages of immunization. Moreover, the antibody from this strain exhibited only a slight change in affinity during the immune response, while the other strains underwent clearcut maturation (progressively increased affinity for NP and increased discrimination between NP and the related compound).Nine F1 hybrid mice between C57BL/6 and CBA produced anti‐NP antibody that was very similar to C57BL/6 anti‐NP.

Genetic Control of the Specificity of Anti-DNP Antibodies

Abstract Differences in the fine specificity of anti-2,4-dinitrophenyl (DNP) antibodies produced by different inbred mouse strains were demonstrated. These differences are expressed in terms of the relative capacity of a given nitrophenyl ligand to inhibit the binding of 3H-DNP-∈-aminocaproic acid (3H-DNP-EACA) by anti-DNP antibodies. The most prominent differences concerned the relative affinity of AKR and of BALB/c anti-DNP antibodies for 2,4-dinitrophenol and 2,4-dinitroaniline and the relative affinity of AL/N and C57BL/6 anti-DNP antibodies for picryl-ε-aminocaproic acid. These strain-specific fine specificity patterns could not be explained by systematic differences in average association constant for 3H-DNP-EACA. The specificity patterns of anti-DNP keyhole limpet hemocycanin and anti-DNP bovine γ globulin antibodies produced by a given strain were generally similar. The differences in fine specificity pattern between AKR and BALB/c anti-DNP antibodies were noted in antisera collected at various times in the course of the immune response. Strain-determined variation in the fine specificity of anti-DNP antibodies may present a model system for studying the genetic control of antibody specificity.