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1.
An eluate prepared by brief incubation of spleen cells from 2,4,6-trinitrophenyl (TNP) lysyl-Ficoll immunized mice with TNP-epsilon-amino-n-caproic acid causes a specific inhibition of the induction of contact sensitivity by 2,4,6-trinitrochlorobenzene skin painting. The active factor in the eluate binds to an anti-mouse immunoglobulin (Ig) immunoadsorbent column but not to a TNP immunoadsorbent column and is therefore Ig but not anti-TNP antibody. The active factor does bind to an immunoadsorbent prepared from anti-TNP antibody, suggesting that the factor has anti-idiotype specificity. Evidence based upon hapten-reversible inhibition of plaque formation and an enzyme-linked immunosorbent assay (ELISA) indicates that the eluates contain auto-anti-idiotype antibody specific for anti-TNP antibody. It is suggested that auto-anti-idiotype antibody spontaneously produced during the immune response to a T-independent antigen can specifically downregulate contact sensitization to the same epitope.  相似文献   

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Using hapten-reversible inhibition of plaque formation as an assay for auto-anti-idiotype antibody (anti-Id) and as a means for following idiotype (Id) expression, we have obtained evidence that following immunization with trinitrophenyl (TNP) conjugates (a) there are differences in Id expression in the anti-TNP antibody response to different TNP conjugates although there is some overlap; (b) different strains, although showing some differences in Id expression, tend to produce cross-reactive Ids, thus no obvious allotype linked inheritance of Id expression is observed in this heterogeneous immune response; (c) the auto-anti-Id produced following immunization with TNP-Brucella abortus or TNP-Ficoll tends to be of the IgG2a and IgG2b isotypes.  相似文献   

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The responses to 2,4,6-trinitrophenyl conjugates of different Ficoll preparations differ with respect to the magnitude of the accompanying auto-anti-idiotype (Id) response in both mice and chickens. Evidence is presented that reduced auto-anti-Id production in the chicken is due to the activation of suppressor activity by some preparations of Ficoll.  相似文献   

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The spontaneous production of auto-anti-idiotype (Id) was demonstrated after injection of chickens with trinitrophenylated Ficoll (TNP-F) by: (a) the presence of hapten-augmentable plaque-forming cells (PFC), (b) the ability of serum and of hapten eluates from immune spleen cells to cause hapten-reversible inhibition of anti-TNP plaque formation, and (c) an enzyme-linked immunosorbent assay (ELISA). Tests for anti-Id using the ELISA and hapten-reversible inhibition of PFC correlated very well. As in the mouse, the incidence of hapten-augmentable PFC was reduced by thymectomy and increased by the transfer of TNP-F-immune spleen cells. Hapten-augmentable PFC were also observed during the immune response of chickens to p-azobenzene arsonate-conjugated Brucella abortus.  相似文献   

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An antigen fraction has been isolated from the water insoluble component of cattle filarial parasiteSetaria digitata by detergent NP-40 solubilization, precipitation with ammonium sulphate and fractionation on sephadex G-100. Immunoglobulin G response to the isolated antigenic fraction was selectively suppressed in asymptomatic microfilaraemic people in comparison to the amicrofilaraemic groups of endemic normals and chronic patients. However, treating microfilaraemic people with diethylcarbamazine enhanced the antibody levels by 10-fold. These results suggest that active infection suppresses the response induced by the isolated antigenic fraction which is elevated after clearance of microfilariae.  相似文献   

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Pompe disease, which results from mutations in the gene encoding the glycogen-degrading lysosomal enzyme acid alpha -glucosidase (GAA) (also called "acid maltase"), causes death in early childhood related to glycogen accumulation in striated muscle and an accompanying infantile-onset cardiomyopathy. The efficacy of enzyme replacement therapy (ERT) with recombinant human GAA was demonstrated during clinical trials that prolonged subjects' overall survival, prolonged ventilator-free survival, and also improved cardiomyopathy, which led to broad-label approval by the U.S. Food and Drug Administration. Patients who lack any residual GAA expression and are deemed negative for cross-reacting immunologic material (CRIM) have a poor response to ERT. We previously showed that gene therapy with an adeno-associated virus (AAV) vector containing a liver-specific promoter elevated the GAA activity in plasma and prevented anti-GAA antibody formation in immunocompetent GAA-knockout mice for 18 wk, predicting that liver-specific expression of human GAA with the AAV vector would induce immune tolerance and enhance the efficacy of ERT. In this study, a very low number of AAV vector particles was administered before initiation of ERT, to prevent the antibody response in GAA-knockout mice. A robust antibody response was provoked in naive GAA-knockout mice by 6 wk after a challenge with human GAA and Freund's adjuvant; in contrast, administration of the AAV vector before the GAA challenge prevented the antibody response. Most compellingly, the antibody response was prevented by AAV vector administration during the 12 wk of ERT, and the efficacy of ERT was thereby enhanced. Thus, AAV vector-mediated gene therapy induced a tolerance to introduced GAA, and this strategy could enhance the efficacy of ERT in CRIM-negative patients with Pompe disease and in patients with other lysosomal storage diseases.  相似文献   

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Although Freund's adjuvant has been used for decades as an immune enhancer in rabbits, adverse physiologic side effects have prompted the search for more suitable alternatives. We used osteocalcin, a bovine bone protein (M.W. 5,800), as the test antigen to evaluate four adjuvant regimens: a) primary inoculation with complete Freund's adjuvant (CFA) followed by three boosts with incomplete Freund's adjuvant (IFA), b) four serial inoculations with RIBI MPL+TDM+CWS adjuvant, c) four serial inoculations with TiterMax #R-1, and d) primary inoculation (only) with TiterMax #R-1. The antibody yield associated with the CFA/IFA regimen (mean OD = 2.152) was at least sixfold that of either TiterMax (mean OD = 0.358) or RIBI (mean OD = 0.239) multiple injection regimens. No antibody response was observed after the single injection of TiterMax antigen emulsion. Maximal antibody production occurred rapidly in response to Freund's adjuvant (day 31) as compared with TiterMax (day 74) and RIBI (day 66).  相似文献   

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Polyclonal antibody production in subcutaneous chambers was compared to traditional antibody production methods in rabbits. The chamber, a sterilized plastic wiffle golf ball that had been surgically implanted in the subcutis of the thoracic region, was immunized via a percutaneous injection of antigen into the core of the ball through one of the perforations in the chamber wall. Rabbits bearing chambers were immunized on the same schedule and with the same concentrations of antigens as were provided the adjuvant injected rabbits. Fluid volumes of 12 to 22 ml could be removed from each chamber at weekly intervals. Chamber antibody to specific microbial antigens was equal to or better than serum antibody produced to the same antigens with Freund's or acrylamide adjuvants. The comfort of the rabbit, the ease in chamber immunization, and the recovery of high titer antibody in large volumes make the subcutaneous chamber an attractive method for polyclonal antibody production.  相似文献   

11.
The enzyme dextranase could degrade antigenic dextran in vivo even when given 6-15 d after the antigen. Dextranase injected after the antigen suppressed the immune response when given 24 but not 48 h after the antigen, indicating that the antigen must interact with the immune system for 48 h to initiate a response. Thereafter, the B cells are independent of further antigen stimulation. To show whether antibody-mediated suppression of the immune response was determinant specific FITC-conjugated SRC were applied as immunogen and antibodies were raised both against the carrier (SRC) and the FITC hapten. When these antibodies were injected 1-3 h after the immunogen they only suppressed the immune response to the corresponding determinant. Anti-carrier antibodies usually enhanced the response to the hapten. Therefore, antibody-mediated suppression of the immune response is determinant-specific and cannot be mediated in vivo to a detectable extent by the Fc part of the antibodies.  相似文献   

12.
Some T lymphocytes produce extracellular proteins that bind nominal antigen specifically (TABM), and these proteins exhibit potent immunoregulatory activity. We have utilized an ELISA for Ag binding by Ag-specific TABM to detect and quantitate the appearance of Ag-specific TABM in murine serum during a humoral Ir to protein Ag. The TABM response was specific for the inducing Ag, stronger and more rapid during a secondary response, and temporally distinct from the appearance of Ig. The non-Ig serum TABM were bound by mAb specific for TCR-alpha chains and isolated by affinity for Ag were Mr 110,000 polypeptides. The TABM response did not occur in scid/scid mice unless the mice were reconstituted with thymocytes and thymocyte-reconstituted scid/scid mice produced TABM, but did not produce Ig. The results suggest that soluble TABM are an Ag-specific humoral manifestation of the Ir of some T lymphocytes.  相似文献   

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Feeding mice sheep erythrocytes (SRBC) caused a significant decrease in splenic IgM antibody responses to SRBC given ip. Reduced IgM responses were due to a suppressor factor in the serum of fed mice rather than due to a lack of IgM antibody-forming cell precursors or to the presence of suppressor T cells. Although feeding initially primed mice to produce greater IgA and IgG anti-SRBC responses after SRBC challenge, the initial primed state was transitory. Mice fed SRBC for longer than 8 weeks had significantly reduced splenic IgG and IgA responses after SRBC challenge.Suppression of IgM responses by serum from fed mice was antigen-specific and not H-2 restricted. Serum from fed mice inhibited the induction of IgM anti-SRBC responses but did not block the expression of already established responses. The size of the suppressor factor and the ability to remove suppressor activity from serum by anti-mouse immunoglobulin suggested that suppression was mediated by antibody. However, the determinants against which the antibody was directed appeared to differ among batches of suppressor sera. Suppressor activity did not appear to be mediated by immune complexes, or soluble antigen. Oral feeding of antigen can have a marked influence on host systemic immune responses when the antigen used for feeding is subsequently administered parenterally. Thus, oral antigen administration may provide a way for specifically manipulating systemic immune responses in vivo. In addition, antigen-feeding may provide a means for producing transferable factors that suppress humoral antibody responses.  相似文献   

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A Mates  N A Hinton 《Microbios》1976,17(68-69):79-86
The primary antibody response of dogs and rabbits to both 'H' and 'O' antigens of Salmonella typhosa following intravenous injection with a formalin killed vaccine from 2.4 x 10(6) to 2.4 x 10(10) organisms/kg body weight was analysed. The animals were restimulated 80 days later with various vaccine concentrations. The lgM anti-'O' and lgG anti-'H' and 'O' antigens in the dogs, were significantly weaker in both primary and secondary response than the comparable rabbit group. Primary lgM anti-'H' response in the dog was found to be greater, equal, or less than that observed in the rabbit. A closer analysis of the primary response indicated that both animal species show the same latent period and doubling time in respect of anti-'H', and the differences observed are probably the result of the number of progenitor cells stimulated by the antigen. On the other hand the suppressed response of the dog to 'O'-antigen is the result of an overall weaker response of this animal to the antigen. The secondary anti-'H' lgM response was found to be greater than, equal to, or less than the primary response in the same animal. The significant inhibition of this response was observed in those animals which received a high primary dose of antigen.  相似文献   

19.
Procedures to quantitate accurately the in vitro phagocytosis of sheep erythrocytes and Aerococcus viridans var. homari (formerly Gaffkya homari) bacteria by hemocytes of the American lobster were utilized to assess the effect of various vaccines on the humoral and cellular defense mechanisms of the lobster. Both the percent of hemocytes showing phagocytosis and the number of particles phagocytosed increased markedly in many of the animals injected with Pseudomonas perolens cells or endotoxin. A lesser response was elicited by A. viridans cellular vaccines. In vivo phagocytosis was observed in the circulatory system of lobsters infected with A. viridans var. homari.Natural hemolymph agglutinins for sheep or rabbit erythrocytes were not affectd by any vaccines. Hemocyte numbers dropped initially after administration of P. perolens endotoxin or cells. The bactericidin level was enhanced in samples taken from vaccinated animals.  相似文献   

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