Article

Studies on delayed hypersensitivity. I. Inferences on the comparative binding affinities of antibodies mediating delayed and immediate hypersensitivity reactions in the guinea pig

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Abstract

Experiments carried out with several well defined antigenic systems (hapten conjugates of poly-L-lysine and guinea pig serum albumin) in guinea pigs demonstrated that: 1. Arthus reactions also manifest carrier specificity, although to a smaller extent than do delayed hypersensitivity reactions. 2. Desensitization by injection of minute doses of antigen results in moderate specific desensitization of delayed hypersensitivity without desensitization of Arthus reactivity to the same antigenic determinant. 3. Insoluble antigen-antibody complexes prepared from high affinity guinea pig antibodies can elicit specific delayed skin reactions in sensitized guinea pigs. 4. Homologous conjugates of structurally similar haptens show considerably less cross-reactivity in delayed reactions than in immediate hypersensitivity reactions to the same antigenic determinant. These experimental results are interpreted as indicating that delayed hypersensitivity reactions in the guinea pig are mediated by "antibodies" of comparatively high binding affinities. High binding affinities are achieved for these antibodies more likely by closer structural adaptation between antigen and antibody than by a larger area of specific contact.

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1. Fluorescence quenching has been calibrated, by comparison with equilibrium dialysis, for measurement of antibody-hapten association constants with guinea pig antibody to the 2,4-dinitrophenyl (DNP) determinant. The maximum quenching with all sites occupied which gave best agreement with equilibrium dialysis was found to be 100%. 2. The carrier to which the DNP-hapten is coupled influences significantly the amount, class (γ1 or γ2), and affinity of the antibody of DNP specificity made by individual guinea pigs. 3. The affinities of γ1- and γ2-antibodies from individual guinea pigs are generally very similar. 4. Precipitin curves with γ1-antibodies show more marked inhibition of precipitation in antigen excess than do precipitin curves with the less charged γ2-antibodies, indicating the importance of nonspecific forces in the precipitation reactions.
Article
Equilibrium measurements of interactions of anti-DNP antibodies, prepared using DNP-PLL and several DNP-proteins for immunization, with DNP0.6-PLL240 and with the univalent hapten, ϵ-DNP-L-lysine, were made utilizing the technique of fluorescence quenching. Carrier specificity of anti-DNP-PLL antibodies was demonstrated by a higher average intrinsic association constant (K0) of anti-DNP-PLL antibodies with DNP0.6-PLL240 than with ϵ-DNP-L-lysine. The free energy contribution of the PLL carrier to the interaction of intact anti-DNP-PLL antibodies with DNP0.6-PLL240 was from –0.8 to –2.1 kcal/mole. On the other hand, intact anti-DNP-protein antibodies displayed a lower energy of interaction with DNP0.6-PLL240 than with ϵ-DNP-L-lysine of up to +2.4 kcal/mole. Fab' fragments of both anti-DNP-PLL and anti-DNP-BGG antibodies have K0's with ϵ-DNP-L-lysine identical to the K0's of the intact anti-DNP antibodies from which they were prepared. However, K0 of interaction of Fab' fragments with DNP0.6-PLL240 (a large proportion of the conjugated PLL molecules in this preparation bear more than one DNP group) is considerably lower than that of the intact antibody. Thus a cooperative effect in the binding of bivalent antibody and bivalent (or greater) antigen exists and is of the order of –1.2 to –2.0 kcal/mole of IgG antibody. Although the direct contribution of the carrier to the interaction of Fab' fragment of anti-DNP-PLL and DNP0.6-PLL240 is –0.4 kcal/mole, the energy of carrier specificity, based upon consideration of cooperative effects and of repulsion of anti-DNP-protein antibodies for portions of the DNP-PLL determinants, is of the order of –3 kcal/mole (approximately 30% of total binding energy).
Article
That the immune response to an immunogen by an individual animal is under genetic control is evident from the results of several studies. For example, Fjord-Scheibel (1943), Carlifanti (1948), and Sang and Sobey (1954) showed a statistically significant relationship between the abilities of parents and their offspring to produce high serum titers of antibody to a given immunogen. Also, Ibsen (1959) showed that inbred strains of mice required different doses of antigen to produce a standardized immune response. Recently, Sobey et al. (1966) observed genetically transmissable differences among random bred mice to respond immunologically to bovine serum albumin. Finally, Arquilla and Finn (1965), in studies of the immune response of inbred guinea pigs to bovine insulin, found that strain 2 guinea pigs could make antibodies to an antigenic determinant of insulin to which strain 13 could not make antibodies. However, breeding studies showed complex patterns of inheritance.
Article
Preimmunization of either guinea pigs or rabbits to bovine gamma globulin (BGG) prepares the animals for markedly enhanced antibody responses to 2,4-dinitrophenyl-BGG (DNP-BGG). This phenomenon is observed both in the primary anti-DNP antibody response to DNP-BGG and in the secondary anti-DNP antibody response to DNP-BGG in animals primed with DNP-ovalbumin (DNP-OVA). The BGG preimmunization is most effective if the antigen is administered as a complete Freund's adjuvant emulsion; in rabbits, a dose of 1 µg of BGG is more effective than a dose of 50 µg, whereas the reverse is true in guinea pigs. Transfusion of homologous anti-BGG sera fails to replace active immunization with BGG in the preparation of animals for these enhanced anti-DNP antibody responses. Both the immunoglobulin class and the average association constant for ϵ-DNP-L-lysine of the anti-DNP antibody produced in these enhanced responses is determined by the mode and time of immunization with haptenic conjugates and is not appreciably influenced by the nature of the carrier preimmunization. These studies indicate that the carrier specificity of hapten-specific anamnestic antibody responses is largely due to the interaction of two independent cell associated recognition units, one specialized for carrier and the other specific for haptenic determinants.
Article
A carrier effect is obtained typically when a hapten-protein conjugate is injected into an animal which has previously been primed with the same hapten conjugated to another carrier protein. Under these circumstances the anti-hapten secondary response is usually less than that which would have been obtained had the animal been injected with a conjugate prepared with the same carrier as that originally used for priming. Attempts have been made to account for the phenomenon in terms of the local environment hypothesis, which assumes that the receptor on immunologically competent cells recognises the hapten jointly with the area on the complete antigen which surrounds it. Alternatively the phenomenon can be accounted for by the hypothesis of cooperation, which assumes that the antigen is recognised by two receptors, one directed to the hapten and the other to a determinant on the carrier protein.
Article
Full-text available
Further data have been presented showing that the specificity of the delayed hypersensitivity reaction in the guinea pig to hapten-protein conjugates involves to a considerable degree a contribution by the protein carrier. The carrier contribution is such that sensitization to guinea pig albumin-m-azobenzenesulfonate, for example, does not result in cross-reaction with conjugates of the same hapten with unrelated proteins such as ovalbumin or human gamma globulin, nor were cross-reactions observed between conjugates prepared with the same hapten, coupled to the same protein, but by two different chemical routes, such that the point of attachment of the hapten to the protein differed. It thus appears that in this system both hapten and carrier protein are necessary, but that neither alone is in general sufficient to stimulate the delayed sensitive cell. Desensitization experiments with cross-reacting hapten-protein conjugates have suggested the presence of a multiplicity of antigenic determinants participating in the elicitation of the delayed lesion, and of a concomitant development of a heterogeneity of specificities in the population of delayed sensitive cells in the sensitized animal. The data are discussed in terms of the apparent requirement of the delayed sensitivity mechanism for a larger functional antigenic determinant than that required for interaction with circulating antibodies. Some possible explanations for this difference, and some of its consequences, are discussed.
Article
Full-text available
The cross-reactions of conjugates carrying structurally related haptens have been studied in guinea pigs with delayed sensitivity to hapten-protein conjugates. The specificity of the delayed reaction has been found to be a function both of the nature and of the position of the substituent on the benzene ring; the cross-reactions shown in the delayed system, however, have been found to be appreciably more extensive than those reported for rabbit antibody systems employing identical haptens. This finding supports the earlier suggestion that the determinant in the delayed system is functionally larger than that required for reaction of antigen with conventional antibody. Desensitization studies with cross-reacting antigens have indicated that the delayed hypersensitivity response is characterized by the production of a heterogeneous population of cells, all more or less closely adapted to the structure of the homologous hapten conjugate.
Article
Dinitrophenyl conjugates of poly-L-lysine, varying in percentage conjugation and molecular weight have been found to induce skin reactivity and precipitating antibodies in guinea pigs. At best, 40 per cent of immunized animals developed delayed and immediate responses to DNP-polylysine, which is believed to reflect constitutional differences among the animals assayed. Only those animals capable of responding to DNP-polylysine, responded to an immunologically distinct poly-α-amino acid consisting of glutamyl and lysyl residues ("copolymer glu-lys"). The percentage of animals responding to the DNP-polylysine antigen decreased as the degree of DNP conjugation increased.
Article
1. Immunization with each of 8 homogeneous antigens led to the formation of multiple antibodies. This is attributed to a different degree of adjustment of the antibody-molecules to particular factors (sub-groups) within the determinant group of the antigen. 2. The bonding force of determinant arsenic-acid groups is stronger than that of sulfonic-acid groups, probably because of their higher ionic strength. A positively charged azoprotein with quaternary ammonium groups proved to be just as powerful an antigen as arsanil-azoproteins. The determinant group of substituted proteins (azoproteins, iodoproteins) includes also a portion of the protein-molecule. 3. We distinguish 3 types of antibodies: a) low-grade, b) imperfect and c) special antibodies. Imperfect antibodies are precipitated only by the homologous antigen, special antibodies by the homologous as well as by heterologous antigens containing the adequate determinant factors. A rational nomenclature for the multiple antibodies of an immune serum is proposed. We designate each antibody by the determinant factors indispensable for its precipitation. The amount of different antibodies in two immune sera to azoproteins has been determined (table 4 and 5). 4. The essential reasons for the attachment of antibody to antigen are briefly discussed.
Article
Guinea pigs rendered hypersensitive (delayed-type) to protein antigen can be completely and specifically desensitized by a single injection containing a sufficient amount of the corresponding antigen. Although 1 to 2 mg. of specific antigen are required for complete desensitization, as little as 20 µg. suffices to decrease the size of specific skin reactions in sensitized animals. The duration of non-reactivity lengthens as the amount of antigen in the desensitizing injection is increased, but skin reactivity eventually returns and is accompanied by the appearance of excess circulating antibody. Desensitization can be accomplished with the antigen-antibody complex as well as by "free" antigen. The appearance of delayed skin reactions can be prevented in fully sensitized animals by intravenous desensitization 2 or more hours after intradermal challenge or by simply skin testing with a desensitizing dose of specific antigen. Injection of a desensitizing dose of antigen into specifically sensitized animals also results in a transient anergic state, the implications of which are discussed.
Article
Adult guinea pigs were made unresponsive to a heterologous protein (e.g. bovine gamma globulin, or BGG) or a hapten-protein conjugate (e.g. p-aminobenzoic acid-bovine gamma globulin, or PABAγmiddot;BGG) by intraperitoneal injection of 80 mg cyclophosphamide and the specific antigen. This immunologic unresponsiveness developed to the specific antigen administered simultaneously with the cyclophosphamide, and not to any variants. Thus, animals unresponsive to PABAγmiddot;BGG remained unresponsive to the original antigen on challenge with a variant, but formed delayed hypersensitivity and circulating antibody to the variant. The specificity of immunologic unresponsiveness, therefore, seems more closely related to the whole antigen molecule than does delayed hypersensitivity.
Article
This chapter formulates the basic concepts for understanding immunologic specificity and stresses the probable importance of apolar interactions in the antigen-antibody reactions. The notion of specificity was nurtured by the commonsense observations made over many centuries that individuals acquired immunity against a particular disease, for example, smallpox, following recovery from that disease. The intensive study of the chemical nature of the combining region of the antibody molecule has begun only very recently. The chapter discusses the aspects of the specific interaction, such as the complementary relationship, the affinity of the specific complex, the contribution of apolar (hydrophobic) interaction, the contribution of columbic interactions, the contributions of hydrogen bonding and the London dispersion force, the steric factor, and the size of the antibody-combining region. It also emphasizes the induction and purification of high-affinity antibody because only with such antibody the interactions reveal their full significance. In this connection the use of relatively large haptenic groups attached to a single kind of protein side chain will provide important advantages. In this way also it may be possible to ascertain the upper limits of the affinity of antigen and antibody and thereby, provide the quantitative basis for elucidating many biological immune processes. The chapter also presents the general considerations of immunologic specificity and molecular structure such as the molecular (organic) crystal as a mode, the haptenic group as a molecular probe, complex formation as the basic process, the free energy of the specific interaction, and intermolecular forces in specific reactions.
Article
The 2,4-dinitrophenyl group, combined with proteins through azo linkage or by substitution in free amino groups, has been studied as a determinant in the precipitin reaction. The precipitin curves obtained resemble those encountered with purified antigens of high molecular weight with the chief exception that in the region of antibody excess antigen is not completely precipitated. Dinitrophenyl-azo-ovalbumin was a less effective precipitant than the conjugated ovalbumin in which dinitrophenyl groups were substituted in free amino groups. The former, however, was relatively more effective in precipitating antibody from antisera to dinitrophenyl-azo-proteins than from antisera prepared against amino-substituted dinitrophenyl-proteins. The globulin fraction of pooled antisera to dinitrophenyl-bovine γ globulin contained at least three species of antibodies—viz: those precipitated by bovine γ globulin; those precipitated by dinitrophenyl-ovalbumin and those precipitated only by dinitrophenyl-bovine γ globulin. These were present in the ratio of 1:1:1.3, respectively. After maximal precipitation with each of these antigens the supernates' binding of ε-N-dinitrophenyllysine, a hapten in which dinitrophenyl is combined with lysine in the same way as in the immunizing conjugate, was determined by the method of equilibrium dialysis. The binding in the three cases, relative to the binding by the unabsorbed immune globulin, was in the ratio of 1:0.6:0.25, respectively. Hence, the antibodies precipitated by bovine γ globulin had no detectable specificity for the dinitrophenyl group, and the antibodies precipitated by the heterologous conjugate (dinitrophenyl-ovalbumin) had a greater affinity for the dinitrophenyl determinant than those antihapten antibodies that required for precipitation the fully homolgous conjugate (dinitrophenyl-bovine γ globulin). Antibodies with dual specificity, i.e., with one specificity for the hapten and a distinctly different one for the protein of the immunizing conjugate, were not detected.
Article
The delayed type of inflammatory response is the most common allergic response encountered in human disease states. It occurs extensively in man as a result of natural infections with bacteria. It does not affect only the genetically susceptible few.
Article
Simultaneous transfer of delayed hypersensitivity to diphtheria toxin and to tuberculin has been accomplished in eight consecutive instances in man using extracts from washed leucocytes taken from the peripheral blood of tuberculin-positive, Schick-negative donors who were highly sensitive (i.e., pseudoreactors) to purified diphtheria toxin and toxoid. The leucocyte extracts used for transfer contained no detectable antitoxin. The recipient subjects were Schick-positive (<0.001 unit antitoxin per ml. serum) and tuberculin-negative at the time of transfer. All the recipients remained Schick-positive for at least 2 weeks following transfer and in every case their serum contained less than 0.001 units antitoxin at the time when they exhibited maximal skin reactivity to toxoid. Evidence is presented which indicates that the transfer factor may be released from leucocyte suspensions under mild conditions in which most of the cells appear to remain morphologically intact. Four adult Schick-positive subjects have been sensitized to diphtheria toxoid by intradermal injection of a few micrograms of purified toxoid in the form of a washed toxoid-antitoxin precipitate. Two of these sensitized individuals showed severe delayed skin reactions specifically directed against diphtheria toxin (or toxoid) at a time when their serum antitoxin level was less than 0.001 units/ml.
Article
As inhibitors of the dextran-human 1 → 6 antidextran system on a molar basis, the series isomaltohexaose τ; isomaltopentaose τ; isomaltotetraose > isomaltotriose was found. The ratio of inhibiting power of these oligosaccharides to one another varied in the serum of different individuals, but remained quite constant in serum samples obtained from a given individual without further immunization over a 3-year period. The data are best interpreted as indicating that the antidextran combining sites produced by a single individual are not homogeneous with respect to the extent of their complementary areas but range in dimensions from sites complementary to a trisaccharide or tetrasaccharide to those complementary at least to a hexasaccharide. The significance of these findings in relation to specificity and cross reactions is discussed.
Article
Guinea pigs rendered hypersensitive (delayed-type) to protein antigen can be completely and specifically desensitized by a single injection containing a sufficient amount of the corresponding antigen. Although 1 to 2 mg. of specific antigen are required for complete desensitization, as little as 20 microg. suffices to decrease the size of specific skin reactions in sensitized animals. The duration of non-reactivity lengthens as the amount of antigen in the desensitizing injection is increased, but skin reactivity eventually returns and is accompanied by the appearance of excess circulating antibody. Desensitization can be accomplished with the antigen-antibody complex as well as by "free" antigen. The appearance of delayed skin reactions can be prevented in fully sensitized animals by intravenous desensitization 2 or more hours after intradermal challenge or by simply skin testing with a desensitizing dose of specific antigen. Injection of a desensitizing dose of antigen into specifically sensitized animals also results in a transient anergic state, the implications of which are discussed.
Article
A study has been made of the immunization of guinea pigs with proteins conjugated with picryl, acetyl and ethoxymethylene-phenyloxazolone groups. Immunization by means of complexes of these substances with anti-protein and anti-hapten antisera have also been studied. Antibody production, anaphylactic and Arthus-type sensitivity and delayed skin sensitivity to the conjugates, to the carrier proteins and to unrelated proteins carrying the same haptenic group have been investigated.Immunization with conjugates is found to be followed by the appearance of delayed hypersensitivity to the protein `carrier' in the absence of detectable antibodies against it, although antibodies are produced at that time against the haptenic group itself. Delayed hypersensitivity to the haptenic group has not been detected at any time: blocking it with specific antibody does not lead to the appearance of delayed sensitivity, but merely suppresses antibody formation against that group.Pure delayed sensitivity has been produced against gelatin, both alone and as a conjugate with picryl. Conjugates with homologous serum proteins are shown to provoke only Arthus-type sensitivity and antibody against the haptenic group.These findings are discussed in view of the light they may throw upon the relation of delayed hypersensitivity to antibody production and upon the process of immunization.
Article
1. The octapeptide Gly(Gly3,Ala3)Tyr was the most effective inhibitor of the fibroin-rabbit antifibroin precipitin reaction among the peptides tested that ranged in size from tetra- to octapeptides (40% inhibition at 5–18 μm/ml). 2. The tetrapeptides were considerably less effective than Gly(Gly3,Ala3)Tyr although one of them, Gly(Gly,Ala)Tyr (20% inhibition at 18–20 μm/ml) has the same qualitative amino acid composition as the most effective octapeptide inhibitor. 3. The dodecapeptide fraction was the most active of the peptides compared, giving 50% inhibition at 5–8 μm/ml. 4. Removal of carboxyl-terminal tyrosine from the active octapeptides resulted in a halving of their effectiveness as inhibitors. 5. The results indicate that, although tyrosine appears to account for a disproportionate part of the binding of peptide to antibody, a sizable segment (at least 8 to 12 residues) of the glycyl, alanyl chain is involved in specific combination.
Article
Guinea pigs sensitized with either hen, duck, or goose egg albumin showed delayed hypersensitivity followed by Arthus reactions to the homologous antigen, but tended to have much weaker delayed responses and slower antibody formation to heterologous antigens. Guinea pigs with delayed hypersensitivity to one of the avian antigens had a slower antibody response to a secondary injection of heterologous antigen than to one of the homologous antigen. Sensitization with a protein conjugated with a hapten such as picryl chloride (Pi) or dinitrofluorobenzene (DFB) resulted in delayed hypersensitivity to the homologous conjugate, the homologous protein, and the homologous protein with a heterologous hapten. Circulating antibody and Arthus reactions occurred subsequently to the homologous conjugate, as well as to the homologous hapten attached to a heterologous protein. Delayed hypersensitivity thus seemed associated with the protein moiety, and Arthus responses with the hapten. Anamnestic responses followed injection of an antigen causing delayed hypersensitivity, but not of a hapten not causing delayed reactions. Thus, animals sensitized initially with Pi·HEA, DFB·HEA, or HEA produced antibodies sooner after a secondary injection of Pi·HEA than did unsensitized animals. No anamnestic response resulted when animals sensitized to Pi·BGG were injected with Pi·HEA. Thus, delayed hypersensitivity is indicated to be a preliminary and immature step in the immune process, with specificity directed against broad, more general features of the protein antigen. This intermediate step is followed by production of circulating antibody to any antigen having a similar basic structure, with the specificity of the antibody also directed against smaller immunologically active sites on the antigen molecule.
Article
1. Quantitative precipitation studies of the antibodies produced in response to the immunization of rabbits immunized with bovine albumin modified by the addition of peptides of glutamic acid, lysine, leucine, or phenylalanine indicated that some of the antibodies were specific for the carrier protein, others were specific for the added polypeptide, and that some require both the modification and at least a part of the carrier protein. 2. Similar quantitative studies on the sera prepared against rabbit albumin which had been modified in the same manner indicated that there were antibodies toward the added polypeptide and possibly some which required a portion of the carrier protein and the modification. 3. The possible explanations for the existence of the antibodies requiring the modification and at least part of the carrier protein are discussed. 4. Absorption experiments on antisera to the modified bovine albumins indicate that similarly modified rabbit albumins precipitate all the antibodies produced in response to the added polypeptide, but that unmodified bovine albumin does not precipitate all of the antibodies and that it may form a nonprecipitating complex with some antibodies which prevents subsequent precipitation with the homologous antigen. 5. The modification of the bovine albumin with various polypeptides was found to weaken the antigenicity of the protein. The length of the added polypeptide chain appears to be more important in the change of specificity than the number of added polypeptide chains.
Article
The effects of the following parameters on the immunologic specificity of delayed and immediate hypersensitivity reactions were investigated in the guinea pig using the picryl and p-toluenesulfonyl systems: (a) the contribution of the carrier protein, (b) the effect of the number of hapten groups per molecule of the immunizing and challenging antigens, and (c) the effect of interposing a 6 carbon chain (ϵ-aminocaproic acid) between the hapten and its usual attachment to the lysine ϵ-NH2 groups of the carrier protein. It was found that induction of delayed hypersensitivity was accomplished equally well with both lightly and heavily coupled conjugates. Sensitized animals which gave strong delayed reactions to the immunizing conjugate cross-reacted poorly or not at all to (a) conjugates of the same hapten with a different carrier protein, or (b) conjugates differing from the immunizing conjugate by having an ϵ-aminocaproyl chain interposed between hapten and its attachment onto the carrier protein. Animals sensitized with either lightly or heavily substituted conjugates exhibited strong delayed reactions to both conjugates, but more intense reactions to the immunizing conjugate were always observed. In contrast to the marker carrier specificity exhibited by the delayed hypersensitivity reactions, immediate hypersensitivity reactions, (specific precipitation, Arthus, and PCA reactions) could be elicited equally well with hapten conjugates of all carrier proteins, as well as with conjugates containing ϵ-aminocaproyl chains interposed between hapten and the carrier protein, provided the number of hapten groups per molecule conjugate was sufficiently high. Both in inducing antibody response and in provoking immediate hypersensitivity reactions, heavily substituted conjugates were considerably more effective than were lightly substituted conjugates. Alternative explanations for these observed differences in specificity between immediate and delayed hypersensitivity reactions are discussed.
Article
Rabbit antisera prepared against conjugates of the benzylpenicilloyl (BPO) bifunctional haptenic group were analyzed to determine whether the antibodies are adapted to only a portion of the large BPO molecule, or to the entire molecule, and whether specificity extends to the lysine side chain and adjoining structures of the immunizing carrier protein. No antibodies adapted to the phenylacetylamine portion of the BPO group could be detected in a pooled rabbit anti-BPO serum globulin fraction by PCA and quantitative precipitin analysis using several phenylacetylamine-protein conjugates as antigens. No antibodies adapted only to the thiazolidine carboxylic acid portion of the BPO molecule were detected in the anti-BPO globulin fraction using quantitative precipitin and hapten inhibition methods. At least the bulk of the anti-BPO antibodies was found to be adapted to the entire BPO haptenic group. By quantitative hapten inhibition of precipitation of the anti-BPO globulin fraction, the anti-BPO antibodies were found to show specificity for a 6 carbon amide side chain corresponding to the lysine side chain through which BPO groups are bound predominantly to protein. The contribution of this 6 carbon chain to antibody-hapten binding was small; (–ΔF°) was calculated to be 460 calories per mole (average). Rabbit anti-BPO antibodies prepared against BPO-rabbit serum albumin conjugates showed specificity also toward structures of the immunizing carrier protein, and possibly toward secondary or tertiary structural configurations. Penicilloyl conjugates of rabbit serum albumin precipitated from 3 individual rabbit antisera more anti-BPO antibodies than did penicilloyl conjugates of heterologous carriers (poly-L-lysine, human serum albumin, and human γ-globulin). Anti-BPO antibodies demonstrated heterogeneity with regard to closeness of fit to the haptenic group, or with regard to the dimensions of the combining sites, or both. It was concluded that at least a large part of anti-BPO antibodies are specifically adapted to a large antigenic unit comprised of the entire BPO group, the lysine side chain, and structural configurations of the immunizing carrier protein.
Article
Dinitrophenyl conjugates of poly-L-lysine, varying in percentage conjugation and molecular weight have been found to induce skin reactivity and precipitating antibodies in guinea pigs. At best, 40 per cent of immunized animals developed delayed and immediate responses to DNP-polylysine, which is believed to reflect constitutional differences among the animals assayed. Only those animals capable of responding to DNP-polylysine, responded to an immunologically distinct poly-alpha-amino acid consisting of glutamyl and lysyl residues ("copolymer glu-lys"). The percentage of animals responding to the DNP-polylysine antigen decreased as the degree of DNP conjugation increased.
Article
The main features of this phenomenon are explicable in terms of high-affinity humoral antibody.
Studies on artificial antigens. I. Antigenicity of DNP-polylysine and DNP copolymer of lysine and glutamic acid in guinea pigs Delayed hypersensitivity. III. Specific desensitization of guinea pigs sensitized to protein antigens
  • F S Kantor
  • A Ojeda
  • B Benacerraf
Kantor, F. S., Ojeda, A., and Benacerraf, B., Studies on artificial antigens. I. Antigenicity of DNP-polylysine and DNP copolymer of lysine and glutamic acid in guinea pigs, J. Exp. Meal., 1963, 117, 55. 13. Uhr, J. W., and Pappenheimer, A. M., Delayed hypersensitivity. III. Specific desensitization of guinea pigs sensitized to protein antigens, J. Exp. Med., 1958, 108, 891.
  • E A Kabat
  • M F Mayer
Kabat, E. A., and Mayer, M. F., Experimental Immunochemistry, Springfield, Illinois, Charles C. Thomas, 2nd edition, 1961, 480.
Delayed hypersensitivity to hapten-protein conjugates. II. Anti-hapten specificity and the heterogeneity of the delayed response
  • A M Silverstein
  • P G H Gell
Silverstein, A. M., and Gell, P. G. H., Delayed hypersensitivity to hapten-protein conjugates. II. Anti-hapten specificity and the heterogeneity of the delayed response, J. Exp. Med., 1962, 115, 1053.