Jin-Gui-Shen-Qi Wan alleviates fibrosis in mouse diabetic nephropathy via MHC class II

ETHNOPHARMACOLOGICAL RELEVANCE

Jin-Gui-Shen-Qi Wan (JGSQW) is a traditional Chinese medicine formula that has been traditionally used to alleviate urinary system ailments such as frequent urination and polyuria. Clinical studies have indicated that when combined with hypoglycaemic drugs, JGSQW exhibits a synergistic effect and can improve diabetic nephropathy (DN), yet its underlying mechanism and targets remain unclear.

AIM OF THE STUDY

This study aims to investigate the therapeutic efficacy of JGSQW and its underlying mechanisms using a DN db/db mouse model.

MATERIALS AND METHODS

Ultrahigh-performance liquid chromatography coupled with mass spectrometry was utilized to analyse the primary active compounds, blood levels, and pharmacokinetics of JGSQW. Additionally, the therapeutic effects of JGSQW and metformin on blood glucose levels, lipid levels, renal function, and renal pathology in diabetic nephropathy mice were investigated using a db/db mouse model. Proteomic analysis was carried out to identify the primary target of JGSQW in treating DN. The mechanism of action was verified by western blotting, immunohistochemistry, and immunofluorescence. Then, molecular docking and molecular dynamics, transfection, drug affinity responsive target stability (DARTS) assay and cell thermal migration assay (CETSA) further validated the targeted binding effect.

RESULTS

JGSQW combined with metformin significantly improved the blood glucose levels, blood lipids, renal function, and renal pathology of DN mice. JGSQW mainly exerted its therapeutic effect on DN by targeting major histocompatibility complex class II (MHC class II) molecules. Immunohistochemistry results showed that JGSQW inhibited the expression of collagen I, fibronectin, and alpha smooth muscle actin (α-SMA) expression. Immunofluorescence and Western blot results showed that JGSQW inhibited the expression of H2-Ab1 and H2-Aa, which are MHC class II molecules, thereby suppressing CD4+ T-cell infiltration and improving diabetic kidney fibrosis. The binding ability of paeoniflorin to H2-Aa was predicted and verified by molecular, DARTS, and CETSA assays. Treatment with 80 μM paeoniflorin effectively alleviated high glucose-induced injury in the MPC-5 injury model. H2-Aa was overexpressed at this model concentration, and Western blotting further confirmed that paeoniflorin reduced glomerular podocyte fibrosis by regulating H2-Aa.

CONCLUSIONS

JGSQW combined with metformin may have a synergistic effect to alleviates renal fibrosis in diabetic nephropathy by downregulating immune complex MHC class II molecules and attenuating the antigen presentation effect of MHC class II on CD4.

Opportunities and challenges in the immunological therapy of pediatric malignancy: a concise snapshot

Over the last 50 years, collaborative clinical trials have reduced the number of children dying from pediatric cancer significantly. Unfortunately, certain tumor types have remained resistant to conventional surgical, radiotherapy and chemotherapy combinations, and relapsing and/or refractory disease remains associated with dismal outcomes. Recently, renewed attention has been given to the role for immunotherapies in pediatric oncology. In fact, these combine several attractive features, including (but possibly not limited to) the specificity for cancer cells, potentially in vivo persistence and longevity, and potency against refractory disease. In this narrative review designed for the academic pediatrician, we will concisely review the biological underpinnings behind the immunological therapy of pediatric neoplasms and illustrate the current humoral, cellular approaches, and novel drugs targeting the immune checkpoint, oncolytic viruses, and tumor vaccines. We will also comment on the future directions, challenges, and open questions faced by the field. What is Known: • Cancer immunotherapy drives immune cells and its humoral weaponry to eliminate tumor cells. • This occurs by recognizing antigens ideally expressed only on tumoral, but not normal/healthy, cells. What is New: • Clinical immunotherapy trials have shown responses in children with relapsing/refractory neoplasms. • Novel humoral/cellular immunotherapies, immune checkpoint inhibitors, oncolytic viruses, and tumor vaccines are currently being investigated in pediatric oncology.

Design of a ProDer f 1 vaccine delivered by the MHC class II pathway of antigen presentation and analysis of the effectiveness for specific immunotherapy

Dermatophagoides farinae (Der f 1) is one of leading cause for allergic asthma, and allergen-specific immunotherapy (SIT) is currently recognized as the only etiological therapy to ameliorate asthmatic symptom. The current study was designed on the major histocompatibility complex (MHC) class II pathway, invariant chain (Ii)-segment hybrids as vaccine basis to explore the efficacy of Der f 1 hybrid vaccine by virtue of Ii as carrier in enhancing the protective immune response to asthma. Initially, we engineered a fused molecule, DCP-IhC-ProDer f 1, to deliver ProDer f 1 antigen via specific dendritic cell-targeting peptides to dendritic cells (DCs). Then the DCP-IhC-ProDer f 1 was immunized to the asthmatic models of murine induced by ProDer f 1 allergen. The findings showed that the cytokine repertoire in the murine model was shifted after SIT, including stronger secretion of IFN-γ and IL-10, and a decreased production of IL-4 and IL-17. ELISA determination revealed that the hybrid displayed weak IgE and IgG1 reactivities, and IgG2a levels were elevated. Furthermore, DCP-IhC-ProDer f 1 treatment inhibited inflammatory cell infiltration in the lung tissues. Our results suggest that the DCP-Ihc-ProDer f 1 may be used as a candidate SIT against asthma.

Gilt required for RTL550-CYS-MOG to treat experimental autoimmune encephalomyelitis

MHC class II-derived recombinant T cell receptor ligands (RTLs) modulate the behavior of pathogenic T cells and can reverse clinical and histological signs of autoimmune disease in experimental autoimmune encephalomyelitis (EAE), experimental autoimmune uveitis (EAU) and collagen-induced arthritis (CIA), and are currently in clinical trials for treatment of multiple sclerosis (MS). To expand the utility of these rationally-designed biologics and explore their mechanism(s) of activity in vivo, we have engineered RTL constructs bearing cysteine-tethered antigenic peptides and demonstrate that the appropriate cysteine-tethered RTLs effectively treat EAE. The data presented here suggests that the mechanism by which antigen-specific tolerance induction by RTLs bearing cysteine-tethered antigenic peptides in vivo involves delivery of RTL/antigen to endosomal compartments for processing and re-presentation by full-length MHC class II, with RTLs bearing cysteine-tethered antigenic peptides requiring gamma-interferon-inducible lysosomal thiol-reductase (GILT) for therapeutic activity.

Therapeutic vaccination of active arthritis with a glycosylated collagen type II peptide in complex with MHC class II molecules

In both collagen-induced arthritis (CIA) and rheumatoid arthritis, T cells recognize a galactosylated peptide from type II collagen (CII). In this study, we demonstrate that the CII259-273 peptide, galactosylated at lysine 264, in complex with Aq molecules prevented development of CIA in mice and ameliorated chronic relapsing disease. In contrast, nonglycosylated CII259-273/Aq complexes had no such effect. CIA dependent on other MHC class II molecules (Ar/Er) was also down-regulated, indicating a bystander vaccination effect. T cells could transfer the amelioration of CIA, showing that the protection is an active process. Thus, a complex between MHC class II molecules and a posttranslationally modified peptide offers a new possibility for treatment of chronically active autoimmune inflammation such as rheumatoid arthritis.

Efficacy of clonal deletion vs. anergy of self-reactive CD4 T-cells for the prevention and reversal of autoimmune diabetes

The self-reactive CD4 T-cells play an essential role in triggering and sustaining organ-specific autoimmune diseases. Silencing or elimination of these cells can prevent and reverse an autoimmune process. We have previously showed that a single dose-administration of a soluble dimeric MHC II-peptide chimera (DEF) in double-transgenic mice delayed the onset autoimmune diabetes, and restored the euglycemia in already diabetic mice for a period of 1 week. DEF dimer protection relied on induction of anergy of diabetogenic CD4 T-cells in spleen, and stimulation of IL-10-secreting T regulatory type 1 cells in pancreas. Herein, we show that an octameric form of DEF has doubled the period of protection and reversal of disease by clonal deletion of diabetogenic CD4 T-cells in both the thymic and peripheral compartments. Deletion occurred by activation-induced cell death subsequent to repartitioning and signaling of FAS-FADD apoptotic module in the plasma membrane lipid rafts. Our previous and present data indicated first, that DEF valence translates into various effects on the antigen-specific CD4 T-cells, i.e., Th2 immune deviation, anergy, and apoptosis. Second, the present findings argue for a better efficacy of clonal deletion than anergy of diabetogenic CD4 T-cells for the protection and reversal of autoimmune diabetes.

Experimental therapy of disseminated B-Cell lymphoma xenografts with 213Bi-labeled anti-CD74

A (213)Bi-labeled antibody to CD74 was evaluated as a therapeutic agent for B-cell lymphoma. The alpha-particle emission, with a half-life of 46 min, is appropriate for therapy of micrometastases. The labeled Ab retained full immunoreactivity, and was potent at single-cell kill of the Raji B-lymphoma cell line. Approximately 30 decays of cell-bound (213)Bi was required for a cell kill of 99%, and dosimetry calculations suggested that the cGy dose delivered was sufficient to produce the level of toxicity observed. A non-reactive control Ab, labeled similarly, also produced toxicity, due to decays occurring in the medium, but was approximately 3-fold less potent than the reactive Ab. In a SCID mouse xenograft micrometastatic model, Ab injection at day 2 or day 5 after tumor inoculation resulted in strong, specific suppression of tumor growth, with some apparent cures.

Monomeric Recombinant TCR Ligand Reduces Relapse Rate and Severity of Experimental Autoimmune Encephalomyelitis in SJL/J Mice through Cytokine Switch

Our previous studies demonstrated that oligomeric recombinant TCR ligands (RTL) can treat clinical signs of experimental autoimmune encephalomyelitis (EAE) and induce long-term T cell tolerance against encephalitogenic peptides. In the current study, we produced a monomeric I-A(s)/PLP 139-151 peptide construct (RTL401) suitable for use in SJL/J mice that develop relapsing disease after injection of PLP 139-151 peptide in CFA. RTL401 given i.v. or s.c. but not empty RTL400 or free PLP 139-151 peptide prevented relapses and significantly reduced clinical severity of EAE induced by PLP 139-151 peptide in SJL/J or (C57BL/6 x SJL)F(1) mice, but did not inhibit EAE induced by PLP 178-191 or MBP 84-104 peptides in SJL/J mice, or MOG 35-55 peptide in (C57BL/6 x SJL/J)F(1) mice. RTL treatment of EAE caused stable or enhanced T cell proliferation and secretion of IL-10 in the periphery, but reduced secretion of inflammatory cytokines and chemokines. In CNS, there was a modest reduction of inflammatory cells, reduced expression of very late activation Ag-4, lymphocyte function-associated Ag-1, and inflammatory cytokines, chemokines, and chemokine receptors, but enhanced expression of Th2-related factors, IL-10, TGF-beta3, and CCR3. These results suggest that monomeric RTL therapy induces a cytokine switch that curbs the encephalitogenic potential of PLP 139-151-specific T cells without fully preventing their entry into CNS, wherein they reduce the severity of inflammation. This mechanism differs from that observed using oligomeric RTL therapy in other EAE models. These results strongly support the clinical application of this novel class of peptide/MHC class II constructs in patients with multiple sclerosis who have focused T cell responses to known encephalitogenic myelin peptides.

Peptide-MHC Class II Dimers as Therapeutics to Modulate Antigen-Specific T Cell Responses in Autoimmune Diabetes

Type 1 diabetes is an autoimmune disorder caused by autoreactive T cells that mediate destruction of insulin-producing beta cells of the pancreas. Studies have shown that T cell tolerance can be restored by inducing a partial or altered signal through the TCR. To investigate the potential of bivalent peptide-MHC class II/Ig fusion proteins as therapeutics to restore Ag-specific tolerance, we have developed soluble peptide I-A(g7) dimers for use in the nonobese diabetic mouse model of diabetes. I-A(g7) dimers with a linked peptide specific for islet-reactive BDC2.5 TCR transgenic CD4(+) T cells were shown to specifically bind BDC2.5 T cells as well as a small population of Ag-specific T cells in nonobese diabetic mice. In vivo treatment with BDC2.5 peptide I-A(g7) dimers protected mice from diabetes mediated by the adoptive transfer of diabetogenic BDC2.5 CD4(+) T cells. The dimer therapy resulted in the activation and increased cell death of transferred BDC2.5 CD4(+) T cells. Surviving cells were hypoproliferative to challenge by Ag and produced increased levels of IL-10 and decreased levels of IFN-gamma compared with cells from control I-A(g7) dimer-treated mice. Anti-IL-10R therapy reversed the tolerogenic effects of the dimer. Thus, peptide I-A(g7) dimers induce tolerance of BDC2.5 TCR T cells through a combination of the induction of clonal anergy and anti-inflammatory cytokines.

A self MHC class II beta-chain peptide prevents diabetes in nonobese diabetic mice

We explored T cell responses to the self class II MHC (I-Ag7) beta-chain-derived peptides in diabetic and prediabetic nonobese diabetic (NOD) mice. We found that one of these immunodominant epitopes of the beta-chain of I-Ag7 molecule, peptide 54-76, could regulate autoimmunity leading to diabetes in NOD mice. T cells from prediabetic young NOD mice do not respond to the peptide 54-76, but T cells from diabetic NOD mice proliferated in response to this peptide. T cells from older nondiabetic mice or mice protected from diabetes do not respond to this peptide, suggesting a role for peptide 54-76-specific T cells in pathogenesis of diabetes. We show that this peptide is naturally processed and presented by the NOD APCs to self T cells. However, the peptide-specific T cells generated after immunization of young mice regulate autoimmunity in NOD mice by blocking the diabetogenic cells in adoptive transfer experiments. The NOD mice immunized with this peptide are protected from both spontaneous and cyclophosphamide-induced insulin-dependent diabetes mellitus. Immunization of young NOD mice with this peptide elicited T cell proliferation and production of Th2-type cytokines. In addition, immunization with this peptide induced peptide-specific Abs of IgG1 isotype that recognized native I-Ag7 molecule on the cell surface and inhibited the T cell proliferative responses. These results suggest that I-Abetag7(54-76) peptide-reactive T cells are involved in the pathogenesis of diabetes. However, immunization with this peptide at young age induces regulatory cells and the peptide-specific Abs that can modulate autoimmunity in NOD mice and prevent spontaneous and induced diabetes.

Effect of genetic background on Ea(d) transgene-mediated protection from murine lupus

The expression of a transgenic encoding the I-E alpha-chain, Ea(d), is highly effective in the protection from systemic lupus erythematosus (SLE) in BXSB and (MRL x BXSB)F1 male mice, in which a mutant gene, Yaa (Y-linked autoimmune acceleration), plays a critical role. To gain further insight into the protective role of the Ea(d) transgene, we compared the effect of the transgene in two additional lupus-prone (NZB x BXSB)F1 and (NZW x BXSB)F1 hybrid mice, in which both F1 female mice develop typical SLE in the absence of the Yaa gene and their F1 males bearing the Yaa gene develop a more accelerated form of SLE. Comparative analysis of the clinical development of SLE in these F1 hybrid mice showed that Ea(d) transgene expression was much more effective in the protection from SLE occurring in the F1 females than in their male counterparts. Our results indicate that the Ea(d) transgene is capable of preventing SLE by inhibiting autoimmune responses, independently of the Yaa gene-accelerating effect, and that its protective capacity is strongly influenced by the genetic susceptibility to SLE in individual strains of lupus-prone mice. In addition, this autoimmune inhibitory effect was shown to be selective for IgG, but not IgM, anti-DNA autoantibody production, and is more specific for anti-gp70 autoantibody than for anti-DNA autoantibody. These results favour the hypothesis that the transgene expression may lead to the modulation of self-peptide presentation, thereby preventing excessive T-cell-dependent activation of autoreactive B cells.

Transfection of IL-2 augments CTL response to human melanoma cells in vitro: immunological characterization of a melanoma vaccine

We have transfected human melanoma cell line 518A2 with the cDNA encoding interleukin-2 (IL-2) or granulocyte-macrophage colony-stimulating factor (GM-CSF), and compared cytokine-producing clones for their ability to induce melanoma-specific cytotoxic T lymphocytes (CTL) from autologous peripheral blood mononuclear cells (PBMC) in vitro. The parental cell line expressed HLA-A1, HLA-A2, ICAM-1, LFA-3, in addition to the common CTL antigens MAGE-1, MAGE-3, tyrosinase, gp100, and Melan-A/MART-1. Stimulation of autologous PBMC responders with the IL-2-transfected clone 518/IL2.14 specifically induced CTL lines reactive with all cell lines derived from the autologous patient. Strikingly, GM-CSF-transfected 518A2 cells did not induce anti-tumor CTL reactivity. CTL induction against 518/IL2.14 was independent of HLA class II expression or CD4 help. The parental cell line 518A2 gained immunogenic properties when high concentrations of IL-2 were supplied exogenously, indicating that IL-2 produced and present at high levels locally by itself enhanced immunogenicity. From the autologous CTL line reactive with 518/IL2.14, clones were generated against an as yet unknown antigen, which was present in all autologous melanoma cell lines as well as in 7 of 15 HLA-A2+ melanoma cell lines tested, but not in melanocytes. These results will be discussed with respect to the possibility of using IL-2-transfected melanoma cells as a vaccine for treatment of patients with melanoma.

Protective major histocompatibility complex genes and the role of interleukin-4 in collagen-induced arthritis

To investigate the role of interleukin (IL)-4 during the triggering of collagen-induced arthritis, we examined the effects of the I-A(b) and I-E protective/suppressive genes and passively administered anti-IL-4 monoclonal antibody. In contrast to the action of I-E expression on its own, which has mainly a suppressive effect post-triggering, the combination of I-A(b) and I-E had a marked protective effect. Assuming, on the basis of previous experience with the I-A(b) allele, that it might act through suppressing early IL-4 production, we treated mice with the 11B11 IL-4-neutralizing antibody around the time of initial immunization with collagen. Treatment over a period extending to 6 days post-immunization exacerbated the arthritis, but when curtailed to 2 days post-immunization (and tested in pristane-primed animals), the disease was reduced. We conclude that IL-4 plays an essential role in triggering the disease.

Prevention of murine lupus by an I-E alpha chain transgene: protective role of I-E alpha chain-derived peptides with a high affinity to I-Ab molecules

The expression of a transgene encoding the I-E alpha chain prevents a lupus-like autoimmune syndrome in BXSB mice. However, it had not been elucidated whether the E alpha d transgene-mediated protective effect results from I-E expression or from the generation of I-E alpha chain-derived peptides (E alpha peptide) displaying high affinity for the I-Ab molecule. To address this question, two different BXSB lines expressing the transgene at low or high levels were crossed with lupus-prone MRL mice; this resulted in three types of (MRL x BXSB)F1 mice, differing in the expression levels of I-E molecules and of E alpha peptides presented by I-Ab molecules. Comparative analysis of these three (MRL x BXSB)F1 mice as well as several BXSB transgenic lines showed that the E alpha d transgene-mediated protection paralleled the expression levels of E alpha peptide presented by I-Ab molecules, but not of I-E molecules on B cells. In addition, use of transgenic and nontransgenic double bone marrow chimeras showed a selective activation of nontransgenic B cells during I-Ab-restricted T cell-dependent immune responses, while both transgenic and nontransgenic B cells were comparably activated during T cell-independent responses. These results favor a model of autoimmunity prevention based on competition for antigen presentation, in which excessive generation of E alpha peptides prevents, because of their high affinity to the I-A molecules, activation of potential autoreactive T and B cells.

Major histocompatibility complex class II+B7-1+ tumor cells are potent vaccines for stimulating tumor rejection in tumor-bearing mice

Mice carrying large established major histocompatibility complex (MHC) class 1+ sarcoma tumors can be successfully treated by immunization with genetically engineered sarcoma cells transfected with syngeneic MHC class II plus B7-1 genes. This approach is significantly more effective than previously described strategies using cytokine- or B7-transduced tumor cells which are only effective against smaller tumor loads, and which cannot mediate regression of longer-term established tumors. The most efficient tumor rejection occurs if both the class II and B7-1 molecules are coexpressed on the same tumor cell. Immunity induced by immunization with class II+B7-1(+)-transfected sarcoma cells involves CD4+ and CD8+ T cells, suggesting that the increased effectiveness of the transfectants is due to their ability to activate both of these T cell populations.

MHC class II-transfected tumor cells induce long-term tumor-specific immunity in autologous mice

Many tumors express peptides that are potentially immunogenic; however, the host's immune system is often not sufficiently stimulated to mediate tumor rejection. The inability to mount a potent antitumor immune response has often been attributed to the lack of generation of sufficient tumor-specific T cell help. Efforts in this laboratory to improve tumor-specific immunity have therefore focused on improving the generation of tumor-reactive T helper cells. Previous studies have suggested that immunity to the murine SaI sarcoma can be significantly improved if the tumor is engineered to express syngeneic MHC class II molecules, and thereby directly present tumor peptides to Th lymphocytes. In the present study we demonstrate that vaccination with class II+ SaI transfectants results in immunity that is extremely effective against high-dose challenges of wild-type SaI tumor. The immunity induced by immunization with these transfectants is also exceptionally long-lived (greater than 6 months) and radiation resistant, suggesting that tumor-specific memory T cells are generated. The resulting immunity is specific for the immunizing tumor and protects autologous mice against challenges of both ascites and solid SaI variants. Depletion and adoptive transfer studies confirm the role of CD4+ T cells in the induced immunity, supporting the hypothesis that improving the generation of Th cells enhances the antitumor immune response. Inasmuch as irradiated or paraformaldehyde-fixed transfectants are as effective as live transfectants in stimulating tumor rejection, these genetically engineered tumor cells may serve as useful vaccines against wild-type neoplasms.

Peptide-antibody conjugates for tumour therapy: a MHC-class-II-restricted tetanus toxin peptide coupled to an anti-Ig light chain antibody can induce cytotoxic lysis of a human B-cell lymphoma by specific CD4 T cells

Anti-idiotype antibody therapy of B-cell lymphomas, despite numerous promising experimental and clinical studies, has so far met with limited success. Tailor-made monoclonal anti-idiotype antibodies have been injected into a large series of lymphoma patients, with a few impressive complete tumour remissions but a large majority of negative responses. The results presented here suggest that, by coupling to antilymphoma idiotype antibodies a few molecules of the tetanus toxin universal epitope peptide P2 (830-843), one could markedly increase the efficiency of this therapy. We show that after 2-hr incubation with conjugates consisting of the tetanus toxin peptide P2 coupled by an S-S bridge to monoclonal antibodies directed to the lambda light chain of human immunoglobulin, human B-lymphoma cells can be specifically lysed by a CD4 T-lymphocyte clone specific for the P2 peptide. Antibody without peptide did not induce B-cell killing by the CD4 T-lymphocyte clone. The free cysteine-peptide was also able to induce lysis of the B-lymphoma target by the T-lymphocyte clone, but at a molar concentration 500 to 1000 times higher than that of the coupled peptide. Proliferation assays confirmed that the antibody-peptide conjugate was antigenically active at a much lower concentration than the free peptide. They also showed that antibody-peptide conjugates required an intact processing function of the B cell for peptide presentation, which could be selectively inhibited by leupeptin and chloroquine.(ABSTRACT TRUNCATED AT 250 WORDS)