lpr T cells vaccinate against lupus in MRL/lpr mice

Prospects of the Use of Cell Therapy to Induce Immune Tolerance

Conditions in which abnormal or excessive immune responses exist, such as autoimmune diseases (ADs), graft-versus-host disease, transplant rejection, and hypersensitivity reactions, are serious hazards to human health and well-being. The traditional immunosuppressive drugs used to treat these conditions can lead to decreased immune function, a higher risk of infection, and increased tumor susceptibility. As an alternative therapeutic approach, cell therapy, in which generally intact and living cells are injected, grafted, or implanted into a patient, has the potential to overcome the limitations of traditional drug treatment and to alleviate the symptoms of many refractory diseases. Cell therapy could be a powerful approach to induce immune tolerance and restore immune homeostasis with a deeper understanding of immune tolerance mechanisms and the development of new techniques. The purpose of this review is to describe the current panoramic scope of cell therapy for immune-mediated disorders, discuss the advantages and disadvantages of different types of cell therapy, and explore novel directions and future prospects for these tolerogenic therapies.

Prenatal Administration of Betamethasone Causes Changes in the T Cell Receptor Repertoire Influencing Development of Autoimmunity

Prenatal glucocorticoids are routinely administered to pregnant women at risk of preterm delivery in order to improve survival of the newborn. However, in half of the cases, birth occurs outside the beneficial period for lung development. Glucocorticoids are potent immune modulators and cause apoptotic death of immature T cells, and we have previously shown that prenatal betamethasone treatment at doses eliciting lung maturation induce profound thymocyte apoptosis in the offspring. Here, we asked if there are long-term consequences on the offspring’s immunity after this treatment. In the non-obese diabetic mouse model, prenatal betamethasone clearly decreased the frequency of pathogenic T cells and the incidence of type 1 diabetes (T1D). In contrast, in the lupus-prone MRL/lpr strain, prenatal glucocorticoids induced changes in the T cell repertoire that resulted in more autoreactive cells. Even though glucocorticoids transiently enhanced regulatory T cell (Treg) development, these cells did not have a protective effect in a model for multiple sclerosis which relies on a limited repertoire of pathogenic T cells for disease induction that were not affected by prenatal betamethasone. We conclude that prenatal steroid treatment, by inducing changes in the T cell receptor repertoire, has unforeseeable consequences on development of autoimmune disease. Our data should encourage further research to fully understand the consequences of this widely used treatment.

T cell vaccination in systemic lupus erythematosus with autologous activated T cells

Systemic lupus erythematosus (SLE) is an autoreactive T cell mediated autoimmune disease. Immunization with inactivated autoreactive T cells may induce idiotype anti-idiotypic reaction to deplete specific subsets of autoreactive T cells involved in SLE. Six SLE patients unsuitable or refused to use immunosuppressants were treated with T cell vaccination. Their clinical manifestations and laboratory parameters including mixed lymphocyte reactions were evaluated. Autoreactive T cell clones were derived from peripheral blood mononuclear cells of the patients and 1 × 107 irradiated T cells were inoculated subcutaneously at 0, two, six and eight weeks, respectively. The enrolled patients were followed up for 32-40 months at an interval of three to six months. The clinical characteristics and laboratory abnormalities improved after inoculation without increasing the dose of corticosteroids and immunosuppressants in most patients. SLE disease activity index (SLEDAI) scores decreased. Proliferative responses against the T cell vaccine were observed in four of six patients. At the time of this report, the six patients remain in clinical remission. No significant side effect from the vaccination was noticed during the follow-up period. The results of this pilot study indicate that T cell vaccination is a safe and effective treatment in SLE.

The mechanisms and applications of T cell vaccination for autoimmune diseases: a comprehensive review

Autoimmune diseases (ADs) are a spectrum of diseases originating from loss of immunologic self-tolerance and T cell abnormal autoreactivity, causing organ damage and death. However, the pathogenic mechanism of ADs remains unclear. The current treatments of ADs include nonsteroidal anti-inflammatory drugs (NSAIDS), antimalarials, corticosteroids, immunosuppressive drugs, and biological therapies. With the need to prevent side effects resulting from current treatments and acquire better clinical remission, developing a novel pharmaceutical treatment is extremely urgent. The concept of T cell vaccination (TCV) has been raised as the finding that immunization with attenuated autoreactive T cells is capable of inducing T cell-dependent inhibition of autoimmune responses. TCV may act as an approach to control unwanted adaptive immune response through eliminating the autoreactive T cells. Over the past decades, the effect of TCV has been justified in several animal models of autoimmune diseases including experimental autoimmune encephalomyelitis (EAE), murine autoimmune diabetes in nonobese diabetic (NOD) mice, collagen-induced arthritis (CIA), and so on. Meanwhile, clinical trials of TCV have confirmed the safety and efficacy in corresponding autoimmune diseases ranging from multiple sclerosis (MS) to systemic lupus erythematosus (SLE). This review aims to summarize the ongoing experimental and clinical trials and elucidate possible molecule mechanisms of TCV.

Peripheral deletion of antigen-specific T cells leads to long-term tolerance mediated by CD8+ cytotoxic cells

Peripheral deletion is one mechanism by which potentially self-reactive clones are removed whether they escape thymic deletion. We have examined the consequences of deleting Ag-specific T cells by i.v. injection of soluble Ag. Deletion of DO11.10 T cells by peptide was mediated predominately via a Fas/FasL mechanism. Animals that underwent deletion were tolerant to subsequent immunization with Ag, even when tolerant mice were given fresh Ag-specific DO11.10 T cells before immunization. Tolerance was mediated by CD8(+) T cells that killed the DO11.10-transgenic T cells in vivo. These data demonstrate that the programmed cell death of large numbers of T cells leads to peripheral tolerance mediated by CD8(+) CTLs.

Apoptosis, tolerance, and regulatory T cells--old wine, new wineskins

Antigen-specific unresponsiveness (or tolerance) has always been an important area of research. Interest in the fate of apoptotic cells and their ability to tolerize has revived interest in some of the older models involving hapten-modified self. Recently, we have examined the mechanisms by which intravenous injection of trinitrophenol-coupled spleen cells leads to systemic tolerance. These studies have revealed an important role for Fas/Fas ligand interactions, caspases, CD40/CD40L, and regulatory CD4+ and CD8+ T cells. Extension of these studies to peripheral deletion of T-cell antigen receptor transgenic T cells has shown that deletion and active regulation of immune responses may be important mechanisms for the control of potentially damaging autoimmune responses.

Alleviation of renal disease and lymphadenopathy in MRL-Fasp(lrcg)/Fas(lprcg) (MR-lpr(cg)) mice neonatally infected with mouse mammary tumor virus encoding superantigen strongly reactive with TCR Vbeta8.2 element

Mouse mammary tumor virus transmitted by FM mice (FM-MMTV) encodes a superantigen (SAg) characterized by strong reactivity with TCR Vbeta8.2 element and broad spectrum of Vbeta reactivity. To investigate what effects the expression in vivo of FM-MMTV SAg exhibits on the course of the disease in a lupus-prone model, MRL/MpJ-Fas(lprcg)/Fas(lprcg) (MRL-lpr9cg) mice, neonatally FM-MMTV-infected MRL-lprcg(MMTV) and uninfected MRL-lpr(cg) mice were compared for various disease parameters. In MRL-lprcg(MMTV), survival was significantly prolonged, glomerulonephritis, proteinuria, and lymphadenopathy were clearly ameliorated, and the production of serum immunoglobulin G (IgG), complement-activating IgG2a, and cryogenic IgG3 autoantibodies, which are thought to be pathogenic to kidneys, and circulating immune complexes (IC), and glomerular IC deposition were significantly suppressed. FM-MMTV infection deleted Vbeta8.2+ cells by about 90% and Vbeta14+ cells less efficiently in all of the CD4+, CD8+, and B220+ CD4- CD8- or double-negative (DN) T-cell populations, and Vbeta8.1+ cells in the CD4+ population but not in the others. Similar deletion profiles of CD8+ and DN T cells support that DN T cells are derived from the CD8 lineage. The results imply that the specific regulation of the immune system with viral SAg has a potential for development of an attractive immunomodulatory therapy of autoimmune diseases.

Anti-T-cell receptor therapy in murine experimental systemic lupus erythematosus

Experimental systemic lupus erythematosus (SLE), similar to that observed after immunization with the human anti-DNA mAb 16/6 Id+, could be induced in mice by injection of 16/6 Id specific T-cell lines. The above T-cell lines were exclusively CD4+ CD8- and the majority of cells expressed the Vbeta8 T-cell receptor (TCR) gene products. Furthermore, lymph node cells of mice immunized with the 16/6 Id were enriched with CD4+ Vbeta8+ T-cells. The TCR used by 16/6 Id-specific T-cells showed a limited homology in their CDR3 junctional regions. Nevertheless, mice injected with the anti-Vbeta8 mAb developed autoantibody titers that were not significantly different from those found in the non-treated, 16/6 Id-injected group.

Lymph node cell vaccination against the lupus syndrome of MRL/lpr/lpr mice

Immunization with pathogenic lymphoid cells has been shown to induce resistance to disease in experimental animal models of cell mediated autoimmunity. In the present work we tested the effectiveness of this approach in a spontaneous murine autoimmune disease, the MRL/lpr/lpr (MRL/1) murine lupus model. We now report that the anti-DNA antibodies and glomerulonephritis of MRL/1 mice could be prevented by the adoptive transfer of spleen cells from MRL/+ mice that had been vaccinated with MRL/1 lymph node T lymphocytes, but not by direct vaccination of MRL/1 mice with their cells. These results indicate that the lupus of MRL/1 mice is susceptible to regulation by adoptive vaccination and that these autoimmune mice lack the ability to raise a suppressive response against their own pathogenic cells.

A quantitative model of autoimmune disease and T-cell vaccination: does more mean less?

According to a simple mathematical model, the activated effector T cells that cause an autoimmune disorder can also cure the disease if administered in large doses. This prediction has been tested in the nonobese diabetic (NOD) mouse model and demonstrates that administration of intermediate doses of a diabetogenic T-cell clone caused early hyperglycemia, whereas a higher dose cured the disease. As discussed here by Lee Segel and colleagues, the proposed application of T-cell vaccination to treat clinical disease obliges immunologists to consider the quantitative complexities of regulation.

Reverse engineering: a model for T-cell vaccination

A class of minimal models is constructed that can exhibit several salient phenomena associated with T-cell inoculations that prevent and cure autoimmune disease. The models consist of differential equations for the magnitude of two populations, the effectors E (which cause the disease), and an interacting regulator population R. In these models, normality, vaccination and disease are identified with stable steady-states of the differential equations. Thereby accommodated by the models are a variety of findings such as the induction of vaccination or disease, depending on the size of the effector inoculant. Features such as spontaneous acquisition of disease and spontaneous cure require that the models be expanded to permit slow variation of their coefficients and hence slow shifts in the number of steady-states. Other extensions of the basic models permit them to be relevant to vaccination by killed cells or by antigen, or to the interaction of a larger number of cell types. The discussion includes an indication of how the highly simplified approach taken here can serve as a first step in a modeling program that takes increasing cognizance of relevant aspects of known immunological physiology. Even at its present stage, the theory leads to several suggestions for experiments.

Attenuation of lpr-graft-versus-host disease (GVHD) in MRL/lpr spleen cell-injected SCID mice by in vivo treatment with anti-V beta 8.1,2 monoclonal antibody

When MRL/lpr (H-2k) spleen cells were intraperitoneally injected into C.B-17-scid/scid (severe combined immunodeficient (SCID)) (H-2d) mice, the SCID (SCID-MRL/lpr) mice manifested a severe wasting syndrome with weight loss, splenic atrophy, and lymphoid cell infiltration in the liver and lung, as seen in lpr-GVHD. In contrast, MRL/+ spleen cell-injected SCID (SCID-MRL/+) mice did not show lpr-GVHD. The spleens of SCID-MRL/lpr mice showed progressive increases in donor CD4+ and CD8+ T cells from 4 to 12 weeks after injection and a decrease in B cells at 12 weeks. SCID-MRL/+ mice showed a stable engraftment of CD4+ and CD8+ T cells and a progressive increase in B cells. Analyses of T cell receptor (TCR) repertoires (V beta 6, V beta 8.1,2 and V beta 11) revealed that the V beta 8.1,2+ T cells were found more frequently in SCID-MRL/lpr mice than in SCID-MRL/+ mice. When SCID-MRL/lpr mice were treated with intraperitoneal injection of an anti-V beta 8.1,2 (KJ16) MoAb, V beta 8.1,2+ T cells were markedly depleted, and the severity of lpr-GVHD was attenuated at 4 and 8 weeks after treatment, in contrast to normal rat IgG-injected SCID-MRL/lpr mice. However, the KJ16 MoAb-treated SCID-MRL/lpr mice suffered from severe lpr-GVHD 12 weeks after treatment, although V beta 8.1,2+ T cells were still maintained at a low level. These findings suggest that V beta 8.1,2+ T cells are a major T cell population that mediates lpr-GVHD in the early stage of lpr-GVHD, but that in the later stage, the other T cell populations may proliferate naturally or in accordance with the depletion of V beta 8.1,2+ T cells, and contribute to the development of lpr-GVHD.

The treatment of autoimmune disease in (NZB/NZW)F1 mice with syngeneic photomodulated splenocytes

(NZB x NZW)F1 (B/W) mice spontaneously develop a disease which is remarkably similar to systemic lupus erythematosus (SLE) in humans. This disease is characterized by the appearance of autoantibodies to double-stranded (ds)DNA and the subsequent development of fatal glomerulonephritis. The prophylactic treatment of B/W mice with syngeneic photomodulated autoimmune spleen cells was found to significantly improve survival, and to inhibit the outgrowth of autoreactive B cells and the production of high-titre IgG anti-dsDNA antibodies. The function of the autoreactive T cells in vivo, however, did not change significantly. Our findings suggested a novel treatment for spontaneously occurring autoantibody-related autoimmune diseases.

Dissociation of autoaggression and self-superantigen reactivity

Self-superantigens have been described as products of endogenous retroviruses of the mouse ('minor lymphocyte stimulating loci') that are capable of interacting without prior processing with conserved domains of TCR V beta chains, causing the activation and deletion of most T cells expressing products of determined V beta gene families [1-4]. The fact that superantigens activate a far higher percentage of T cells (1-20%) than conventional, peptidic antigens (< 0.1%) provides the methodological advantage that the degree of clonal deletion may be measured by the analysis of the TCR repertoire using appropriate anti-V beta antibodies. Although much information on the spatio-temporal organization of repertoire-purging has been gathered by virtue of self-superantigens, serious doubts exist as to the possibility that such structures serve as pathogenetically relevant autoantigens. Thus, certain inbred mice spontaneously develop autoimmune diseases, although they bear T-cell repertoires that appear to be purged from self-superantigen-reactive V beta products. In addition, therapeutic interventions targeted to V beta gene products that are not specific for self-superantigens are successful in preventing disease development. The lack of correlation between superantigen-related V beta deletions and autoimmune disease development is substantiated in further models of murine autoimmunity. Based on these observations, we formulate the hypothesis that self-superantigen-reactive T cells are not involved in the development of autoimmune diseases.

Attenuation of autoimmune disease and lymphocyte accumulation in MRL/lpr mice by treatment with anti-V beta 8 antibodies

MRL-MP-lpr/lpr mice are afflicted by a severe systemic autoimmune disease that is aggravated by the lpr mutation resulting in the accumulation of phenotypically abnormal lpr cells (CD3+CD4-CD8-) in all lymphoid issues including hyperplastic lymph nodes. Given that products of the T cell receptor V beta 8 gene family are overrepresented among lpr cells, different schedules aimed at selectively decreasing the frequency of lpr cells were designed. First, continuous administration of the monoclonal antibody F23.1 (specific for V beta 8 products) resulted in a significant depletion of V beta 8+ cells and prevented the manifestation of lymph accumulation at the same time as it reduced the serological, clinical, and histopathological signs of autoimmune disease. Along the same line, administration of either F23.1 or two different anti-F23.1 anti-idiotypic antibodies to MRL/Mp-lpr/lpr mothers elicited, in the offspring, the production of antibodies sharing a recurrent idiotype with F23.1 and resulted in long-term amelioration of autoimmunity and lymphadenopathy. Thus, a strategy aimed at specifically reducing the frequency of a subset of lpr cells proved successful in mitigating the autoimmune process.