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Division of Rheumatology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
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latency-associated protein. These findings suggest possible relevance of Ag specificity in the mechanism of TR-mediated immune tolerance to Ig-derived peptides in NZB/W F1 mice. |
Introduction |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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We have recently shown that NZB/W F1 mice can be protected from developing SLE when given high i.v. doses of a synthetic peptide (pConsensus, pCons) that is based on shared CDR1/framework 2 epitopes encoded within the VH region of several murine anti-dsDNA Ig (4). Tolerance with pCons is very powerful and clinically superior to that achievable with other wild anti-dsDNA-Ig-derived peptides in delaying proteinuria and kidney disease in NZB/W F1 mice (4). The purpose of this work was to investigate the characteristics of peptide-reactive T lymphocytes in this murine model of acquired peripheral tolerance to systemic autoimmunity using soluble I-Ed dimers loaded with pCons. We describe in this work some characteristics of the CD4+ T cells reactive to the tolerizing Ig-derived peptide that suppress in vitro production of anti-dsDNA Ab.
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Materials and Methods |
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NZB (H-2d/d), NZW (H-2z/z), and NZB/W F1 (H-2d/z) mice were bred and maintained at the University of California or purchased from The Jackson Laboratory (Bar Harbor, ME). Mice were treated in accordance with the guidelines of the University of California Institutional Animal Care and Use Committee, which is accredited by the Association for Assessment and Accreditation of Laboratory Animal Care. All experiments were conducted in female mice.
Antigens
The synthetic peptide pCons (FIEWNKLRFRQGLEW) is an artificial peptide designed to contain I-Ed-binding T cell determinants identified in several different J558 VH regions of anti-dsDNA Ig of NZB/W F1 mice, and has been described previously (4). The control peptide pHyHEL (VKQRPGHGLEWIGEI) is nonstimulatory for T cells of naive NZB/W F1 mice; it is I-Ed restricted, derives from the CDR1/framework 2 VH region of a murine mAb against hen egg lysozyme (HEL), and is highly immunogenic in NZB/W F1 mice (4). Peptides were synthesized by a macrocrown method at Chiron (San Diego, CA), purified to single peak on high-performance liquid chromatography, and analyzed by mass spectroscopy for expected amino acid content.
Treatment of mice
For tolerance induction, 10- to 12-wk-old NZB/W F1 female mice received a single i.v. dose of 1 mg of peptide dissolved in saline (4). Age- and sex-matched NZB/W F1 controls received equal volume of saline i.v. For immunization, age-, sex-, and strain-matched mice were immunized once s.c. with 20 µg of peptide dissolved in CFA (1:1 v/v) with or without boost (depending on the experimental protocol) with the same peptide in IFA (1:1 v/v) 10 days after immunization (5).
Cell isolation and staining
Single cell suspensions were prepared by passing through a sterile wire mesh the spleens of mice 1 wk after tolerization or immunization or after control saline treatment. After lysis of RBC with lysing buffer, cells were centrifuged and washed before resuspension in HL-1 complete medium (BioWhittaker, Walkersville, MD). To isolate peptide-reactive T cells, divalent MHC class II (I-Ed) molecules covalently bound to human IgG1-Fc (generous gift of K. Karjalainen, Institute for Research in Biomedicine, Bellinzona, Switzerland) were loaded at a molar ratio of 1:10 with peptide at pH 4.8 (6) before incubation for 30 min with purified splenocytes. The multimeric nature of the MHC class II complex significantly increases the avidity of this chimeric molecule for cognate ligands, thus overcoming the low-affinity constraint of the I-Ed/TCR interaction and enabling direct isolation of Ag-reactive T cells (7, 8). After wash and mouse Fc
R block, FITC-conjugated goat anti-human IgG1-Fc and fluorochrome-labeled Ab to relevant surface markers or control isotype-matched fluorochrome-labeled Ab were added for 20–30 min at 4°C in PBS/2% FCS. The following mAb were used (all from BD Pharmingen, San Diego, CA): anti-CD4 (PerCP), anti-CD25 (allophycocyanin), anti-CD45RB (PE), anti-CD69 (PE), anti-CTLA-4 (PE), and related Ig isotype- and fluorescence-matched control Ab. The following biotinylated Ab and matched biotinylated controls were from R&D Systems (Minneapolis, MN) and were detected with streptavidin-PE (BD Pharmingen): anti-TGF1 latency-associated protein (LAP), antiglucocorticoid-induced TNFR family member 18 (GITR) anti-TGF-RII, and GITR ligand (GITR-L). After wash, cells were sorted via FACSVantage cell sorter or analyzed on a FACSCalibur (BD Biosciences, San Jose, CA) with CellQuest software (BD Biosciences).
For ELISPOT assays, selected lymphocyte subsets were sorted via magnetic bead separation with the automated AutoMACS system (Miltenyi Biotec, Auburn, CA). Briefly, splenocytes prepared as above underwent AutoMACS positive selection with CD4 or B220 magnetic beads (Miltenyi Biotec). Moreover, FACSVantage-sorted Ag-specific cells were AutoMACS purified using the Miltenyi CD4+CD25+ regulatory T cell isolation kit, according to the manufacturer’s instructions. Purity of sorted lymphocytes was always >98%, as assessed by flow cytometry analysis on purified cells. Eluted cells were washed before experimental use.
Proliferation assays
Triplicate cultures (200 µl each) were established in 96-well flat-bottom microtiter plates with HL-1 complete medium and maintained at 37°C in 5% CO2 for 3 days. Peptides (20 µg/ml) and/or mouse rIL-2 (R&D Systems) (10–100 U/ml) were added to the wells according to the experimental protocol. Cells were pulsed with 1 µCi of [3H]thymidine for the last 12–18 h, and incorporation of [3H]thymidine into DNA assessed by liquid scintillation counting in an automated counter (Beckman Coulter, Fullerton, CA). Results are expressed as mean stimulation index or mean cpm ± SE and represent the average cpm of triplicate determinations.
Cytotoxicity assays
CD4+CD25+ and B cells, purified as described above, were incubated in the presence or in the absence of 20 µg/ml pCons. Standard 4-h cytotoxicity assays were performed using the CytoTox 96 nonradioactive cytotoxicity assay from Promega (Madison, WI), following the manufacturer’s instructions.
RT-PCR
Total cellular RNA was extracted with TRIzol reagent (Invitrogen Life Technologies, Carlsbad, CA) from 1 x 105 pCons-reactive CD4+CD25+ cells sorted, as described above, from tolerized mice or saline-treated controls. RT-PCR was performed using the Invitrogen Superscript One-Step RT-PCR with Platinum Taq kit in a volume of 50 µl/reaction, following the manufacturer’s instructions, on a Hybaid PCR Express thermocycler (Milford, MA). The sequence of Foxp3 and hypoxanthine phosphoribosyltransferase primers and the PCR conditions have been described by Hori et al. (9).
ELISA
Cytokine measurement in the supernatant of cultured cells was performed with BD OptEIA ELISA kits (BD Biosciences).
ELISPOT assays
AutoMACS-purified cells (see above) were cultured in 12-well microtiter plates at 37°C in complete medium in the absence or in the presence of pCons (20 µg/ml). B cells derived from untreated 24- to 32-wk-old nephritic NZB/W F1 mice were seeded at a 1:10 ratio of B cells to CD4+ or CD4+CD25+ T cells (in toto or pCons reactive) from tolerized or saline-treated control mice. Ratio of CD4+ or CD4+CD25– cells from control mice and CD4+CD25+ T cells from treated mice was 1:1. In selected experiments, at the beginning of culture, 10–50 µg/ml anti-TGF-LAP or anti-GITR or CTLA-4 Ig (all from R&D Systems) was added to plates. After 5 days, cells were transferred to microtiter plates coated with calf thymus dsDNA, and cells secreting anti-DNA IgG identified by incubation with alkaline phosphatase-conjugated anti-mouse IgG, followed by addition of 5-bromo-4-chloro-3-indolyl phosphate chromogen/0.6% agarose. Enumeration of blue spots was reported as number of Ab-forming cells (AFC) per 105 or 106 B cells. Data for each experiment were reported as means (± SD) of each set of triplicate assays.
Statistics
Statistical analysis was performed using Prism 4 software (GraphPad, San Diego, CA). Parametric testing was performed using the unpaired t test; nonparametric testing was used when data were not normally distributed. Values of p <0.05 were considered significant.
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Results |
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Ten-week-old mice were injected i.v. with 1 mg of the anti-dsDNA Ig-derived synthetic peptide pCons and Ag-specific proliferative responses assayed 1 wk after treatment. The treatment is known to delay development of SLE in NZB/W F1 mice by delaying appearance of anti-dsDNA Ab and proteinuria (4). Control mice received either pCons under immunizing conditions (1:1 v/v in CFA) or saline, respectively. One week after treatment, splenocytes were harvested and stimulated in vitro with either pCons or with pHyHEL, an I-Ed-binding, nonself peptide. As shown in Fig. 1a (columns), splenocytes of tolerized mice had weak proliferative responses to pCons or to control pHyHEL (p NS), whereas significant Ag-specific proliferation was observed when splenocytes derived from pCons-immunized mice (p < 0.001). We also found significant decrease of IL-2 production in the presence of pCons, but not pHyHEL, in the cultures of splenocytes from tolerized mice (p < 0.002) (Fig. 1a, top bars). To test the possibility of anergy in Ag-reactive T lymphocytes after i.v. administration of pCons, we measured lymphocyte proliferation in the presence of rIL-2. Exogenous IL-2 induced proliferation to pCons of splenocytes from tolerized mice (p < 0.002), but not saline-treated controls (NS) (Fig. 1b). To link these findings to functional outcome on immune cell subsets, ELISPOT experiments were conducted in which B cells from old mice were cocultured with purified CD4+ T cells from saline-treated or tolerized mice in the presence of scalar doses of pCons. Dose-dependent increase of T cell help for the production of anti-dsDNA AFC with increased concentrations of peptide in saline-treated mice was accompanied by significantly reduced T cell help for the B cell production of anti-dsDNA AFC in pCons-tolerized mice (p < 0.0003, <0.005, and <0.02 at 40, 20, and 10 µg/ml, respectively) (Fig. 1c).
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To further study the effects of pCons-induced tolerance in NZB/W F1 mice, we isolated Ag-reactive T cells using I-Ed dimers loaded with peptide. First, to confirm validity of the approach, we immunized s.c. 10-wk-old mice with pCons in CFA (1:1 v/v) and boosted immunized animals 10 days later with pCons in IFA. A control group of mice was treated with saline following the same protocol. One week after boost, mice were sacrificed and splenocytes were incubated with pCons-loaded dimers before analysis by flow cytometry. Fig. 2 shows that there was 
10-fold increase in the number of pCons-reactive CD4+ cells in the peptide-immunized mice vs controls. Background staining with dimers loaded with a nonself-derived control peptide (pHyHEL) on splenocytes from saline-treated control mice ranged from 0.4 to 1% (data not shown).
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23.1 ± 11.1 vs 1 ± 0.4% in the control mice. The expansion of pCons-reactive CD4+CD25+ T cells after tolerization pertained to bona fide regulatory T cells, as Foxp3 mRNA was expressed in pCons-reactive CD4+CD25+ T cells of both tolerized and control NZB/W F1 mice, but not in control CD4+CD25– cells (Fig. 3f).
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The phenotype of CD4+CD25+ T cells was only moderately affected by tolerance induction, as indicated by flow cytometry studies. Analysis of molecules involved in immune regulation (10) indicated that peptide-induced tolerance up-regulated the expression of TGF-LAP on CD4+CD25+ T cells, independently of Ag specificity but depending on tolerance, while surface expression of CTLA-4 or GITR was not affected (Fig. 4). However, no significant differences were observed in the surface expression of markers of cellular activation (CD69) or memory (CD45RBlow) on in toto CD4+CD25+ T cells or on pCons-reactive CD4+CD25+ T cells from controls vs tolerized mice (Fig. 4).
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Next, we wondered whether expansion of pCons-reactive CD4+CD25+ T cells after tolerance (Fig. 3) was associated with regulation of autoantibody production. In particular, we asked whether the use of pCons would be responsible for different quantitative or qualitative functional outcomes if administered under tolerizing vs immunizing conditions. Because immunization with pCons also elicited expansion of T cells (Fig. 1a), we addressed whether quantitative influences or qualitative (functional) differences between immunization and tolerization were secondary to the route and regimen of administration of pCons. To address this issue, we isolated pCons-reactive CD4+CD25+ T cells from tolerized or immunized mice for ELISPOT assays, to assess provision of T cell help to the production of anti-dsDNA from B cells. Interestingly, tolerization with pCons induced Ag-reactive CD4+CD25+ T cells that suppressed anti-dsDNA AFC, while pCons-reactive CD4+CD25+ T cells raised by immunization provided help for the production of anti-dsDNA AFC (Fig. 5). In contrast, suppression of anti-dsDNA AFC between in toto CD4+CD25+ T cells from tolerized and immunized mice was not significant (Fig. 5).
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Suppression did not occur in transwell experiments in which peptide-binding T regulatory cells (TR) from tolerized mice were seeded in wells separated from B cells (data not shown), suggesting that pCons-reactive CD4+CD25+ T cells might suppress anti-dsDNA Ab production via cell contact. Therefore, we investigated whether CD4+CD25+ T cells were cytotoxic for B cells. Purified CD4+CD25+ T cells from tolerized mice were coincubated with B cells of untreated old mice in the presence or in the absence of 20 µg/ml pCons, and cytotoxic responses were analyzed. No differences in lysis were observed in the presence or in the absence of peptide (10.8% ± 4.2 vs 13.4% ± 5.1 at an E:T ratio of 50:1, and 7.6% ± 4.0 vs 7.2% ± 3.4 at an E:T ratio of 25:1, respectively; NS) (p between B cells only and B cells plus pCons also NS). These findings suggested that tolerance could not induce TR-mediated cytotoxicity against B cells. B cells plus pCons only had spontaneous lysis similar to B cells alone, indicating lack of peptide toxicity for B cells. Next, we tested whether suppression of TR targeted CD4+CD25– T cells, as suggested in several other systems (10). To this aim, we performed ELISPOT assays in which purified pCons-reactive CD4+CD25+ T cells were either coincubated with only B cells from old NZB/W F1 mice or with B cells together with CD4+CD25– T cells. Suppression of anti-dsDNA AFC occurred to a similar extent when CD4+CD25+ T cells were coincubated with B cells only or when CD4+CD25+ T cells were cocultured with B cells and CD4+CD25– cells (Fig. 6). Because Ag-reactive CD4+CD25+ T cells might not require CD4+CD25– T cells for suppression of anti-dsDNA AFC, we performed ELISPOT experiments in which Ag-reactive tolerized CD4+CD25+ T cells were coincubated with B cells only in the presence or in the absence of Ab to molecules possibly involved in CD4+CD25+-mediated immune regulation. Presence in culture of Ab to GITR or to TGF-LAP, but not isotype control Ab (data not shown), reversed suppression of anti-dsDNA AFC, whereas presence of CTLA-4 Ig in the culture did not significantly affect the response (Fig. 6). Reversal of suppression was possibly related to interactions between TR and B cells, as both TGF-RII and GITR-L were expressed on the B cells of NZB/W F1 mice (Fig. 7).
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Discussion |
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Following the identification of CD4+CD25+ T cells as suppressors of immune responsiveness by Sakaguchi et al. (13), there has been widespread interest in dissecting the mechanisms by which these cells may exert their regulatory effects and which autoimmune diseases they may regulate. Recently, Crispin et al. (14) found that CD4+CD25+ T cells are significantly decreased in the blood of patients with clinically active SLE when compared with healthy controls. NZB/W F1 mice have low numbers of peripheral CD4+CD25+ T cells compared with other strains, and this might contribute, at least in part, to the inability of these mice to maintain immune homeostasis. Interestingly, we show that there is a possibility to expand functional regulatory T cells in this mouse poised to develop systemic autoimmunity. These findings are consistent with the observation in other systems of expansion of Ag-reactive TR to self Ag or to Ag presented in a tolerogenic form or by a tolerogenic route (15, 16, 17). In view of those observations and ours, it would be tempting to speculate that Ag specificity of TR cells might have the teleological advantage of specifically dampening autoreactive responses to avoid deleterious broader effects. However, additional studies are required to address this issue and define related operating mechanisms.
In a recent study, Mozes and colleagues (18) found that suppression exerted by a dual altered peptide ligand (composed of two myasthenogenic peptides) in experimental autoimmune myasthenia gravis was mediated by both CD4+CD25+ TR cells and by up-regulated secretion of TGF. Similarly, Horwitz and colleagues (19) showed that depletion in humans of peripheral blood CD4+CD25+ T cells before priming with TGF markedly decreased immune suppression. Other studies had concluded that CD4+CD25+-mediated suppression did not occur via secreted TGF1 because of the requirement for cell contact and the failure to reverse suppression with anti-TGF Ab (10). However, Nakamura et al. (20) proposed that CD4+CD25+ T cells expressing cell surface latent TGF1 on target CD4+/CD25– T cells (TGF-LAP) could mediate cell contact-dependent suppression through latent TGF1 via the TGF receptor. This conclusion was based on the evidence of cell surface TGF-LAP on CD4+CD25+ T cells and on the observation that Ab to TGF completely abrogated suppression (20). In contrast, Piccirillo et al. (21) found that CD4+CD25+ T cell suppression was equally effective on responder CD4+CD25– T cells from wild-type mice or from Smad3–/– or dominant-negative TGF-RII transgenic mice (which are unresponsive to TGF). Moreover, CD4+CD25+ cells from neonatal TGF1–/– mice suppressed CD4+CD25– as much as CD4+CD25+ T cells from TGF1+/+ mice (21). Although the findings by Piccirillo et al. suggested independence from TGF for CD4+CD25+-mediated suppression on CD4+CD25– responses, we find that CD4+CD25+ T cells may still use this pathway to suppress B cell-mediated humoral responses, consistent with the findings of other authors in other systems (18, 22). Our results are not in contrast with the findings by Piccirillo et al. because: 1) those authors only evaluated suppression on CD4+CD25– cells, but not on B cells (which also express the receptor for TGF-LAP); 2) in our system, TGF-LAP was up-regulated under tolerizing conditions; and 3) there is evidence for the presence of Smad-independent pathways in TGF receptor signaling (23).
In any case, the finding of tolerance-induced expansion of pCons-reactive CD4+CD25+ T cells seems to suggest a (self) Ag-driven process in a fashion similar to that recently reported by Cozzo et al. (15) in a transgenic mouse system in which a self peptide drives peripheral expansion of CD4+CD25+ TR. Because in our model pCons accelerates onset and progression of SLE when administered under immunizing conditions (data not shown), it is reasonable to imagine that the T cells reactive to the self Ig in NZB/W F1 mice can either promote or suppress pathogenic autoimmunity depending on the context (environment) in which the response takes place. In other words, triggering protective vs pathogenic responses might not depend on the presence of the self Ag per se, but rather on the context in which it is recognized (24). We may imagine a scenario in which several factors may contribute to determining quantitative and qualitative outcomes of the Ag-reactive T cells. In particular, the maturation/activation state of the APC that activates the TR and its anatomical location should be a pivotal factor (25), while other important players could be the avidity and composition of the naive repertoire of the Ig-reactive TR cells emerged from the thymus (26). In this sense, our findings of peripheral pCons-reactive cells in controls need an explanation. When using I-Ed dimers loaded with other individual anti-dsDNA Ig-derived peptides, we always found lesser amounts of Ag-reactive cells to the other peptides (our unpublished observations). We hypothesize that because pCons is based on an algorithm that encompasses several sequences common to different anti-dsDNA Ig, it may be responsible for broad reactivity. This could as well explain why pCons induces suppression of T cell help to several stimulatory anti-dsDNA Ig peptides and tolerizes to several other autoantigens (4). In contrast, it must be acknowledged that induction of TR via i.v. delivery of high quantities of the pCons (self Ig-derived) peptide most likely also involves additional factors that influence the signaling at the immune synapse such as professional APCs (and related expression of costimulatory molecules), concentration of available peptide/MHC complexes, avidity and kinetics of T cell/APC interaction, and other factors including the cytokine milieu (27).
Thus, TR cell activity in our system may be only one of several mechanisms aiming in concert at preserving immune homeostasis and protect from autoimmunity. Other mechanisms could include decreased concentration of self Ag, exhaustion of autoreactive effectors, molecular and cellular feedback circuits that decrease the number or function of specific lymphocyte subsets different from TR via apoptosis, tuning of the repertoire (28), and/or the induction of CD8+ suppressors (29). Regarding this last possibility, Fan and Singh (30) reported that genetic vaccination with minigenes encoding NZB/W F1 anti-DNA (VH-derived) MHC class I-binding epitopes activated cytotoxic CD8+ T lymphocytes, which lysed autoantibody-producing NZB/W F1 B cells, with subsequent protection from SLE. In a separate work, we show that certain subsets of CD8+ T cells of NZB/W F1 mice can suppress clinical autoimmunity, under certain circumstances (B. H. Hahn, R. P. Singh, F. M. Ebling, and A. La Cava, manuscript in preparation). Although several mechanisms may therefore be operating in young NZB/W F1 mice to avert autoimmunity, the data presented here suggest that intervention inducing TR during early or preclinical stages of the disease, possibly complemented by concomitant depletion of autoantibody-producing B cells, could possibly have beneficial effects.
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Acknowledgments |
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Footnotes |
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1 This work was supported by Grants AI46776 and AR36834 from the National Institutes of Health (to B.H.H.), by grants from the Lupus Foundation and Arthritis National Research Foundation (to A.L.C.), and by gifts from the Arthritis Foundation Southern California Chapter, the Dorough and Paxson Foundations, and Jeanne Rappaport. 
2 Address correspondence and reprint requests to Dr. Antonio La Cava, Division of Rheumatology, David Geffen School of Medicine, University of California, 1000 Veteran Avenue 32-59, Los Angeles, CA 90095-1670. E-mail address: alacava{at}mednet.ucla.edu
3 Abbreviations used in this paper: NZB, New Zealand Black; GITR-L, GITR ligand; AFC, Ab-forming cell; GITR, glucocorticoid-induced TNFR family member 18; HEL, hen egg lysozyme; LAP, latency-associated protein; NZW, New Zealand White; pCons, pConsensus; SLE, systemic lupus erythematosus; TR, regulatory CD4+ T cell.
Received for publication December 16, 2003. Accepted for publication June 17, 2004.
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References |
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-chains (CD25): breakdown of a single mechanism of self-tolerance causes various autoimmune diseases. J. Immunol. 155:1151.[Abstract]
in the generation and expansion of CD4+CD25+ regulatory T cells from human peripheral blood. J. Immunol. 166:7282.. J. Exp. Med. 194:629.1 production and responsiveness. J. Exp. Med. 196:237. family signalling. Nature 425:577.[Medline]
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) or with 20 µg of pHyHEL (
) or pCons peptides (
). Ag-specific proliferation was seen after immunization (p < 0.001), but not after tolerization or in controls. Also, secretion of IL-2 was decreased in the supernatant of splenocytes from tolerized mice stimulated with pCons (p < 0.01) (top). Stimulation index (S.I.) to Con A was 
7 in all groups (data not shown). b, Tolerization with pCons anergizes peptide-reactive T cells, as indicated by proliferation (columns ± SD) to pCons in the presence of IL-2 (p < 0.002). Representative of three experiments on groups of four to six mice. c, Tolerization of NZB/W F1 mice with pCons induces CD4+ T cell hyporesponsiveness, as indicated by ELISPOT assays with scalar doses of pCons. Less AFC were produced by B cells from nephritic NZB/W F1 mice in the presence of CD4+ cells from tolerized (
) than saline-treated (•) mice. Representative experiment of three on groups of three mice each.
