Predominant inhibition of Th1 cytokines in New Zealand black/white F1 mice treated with FK506

High Frequency of Concomitant Food Allergy Development and Autoantibody Formation in Children Who Have Undergone Liver Transplantation

BACKGROUND

Allergy and other immune-mediated diseases are more frequently reported in children who have undergone liver transplantation. Furthermore, autoantibodies are also prevalent, suggesting a state of immune dysregulation in these patients. Whether or not these processes occur simultaneously in the same individual has not been studied previously.

METHODS

A cohort of 43 children who had undergone liver transplantation for nonautoimmune liver disease at median age of 1.3 years was investigated for allergy and autoimmune disease. Sensitization to food and inhalant allergens was assessed, and autoantibodies were measured.

RESULTS

The prevalence of food allergy was 26% and that of respiratory allergy was 23%, whereas 33% and 26% of the subjects were sensitized to food and inhalant allergens, respectively. Autoimmune disease (ie, autoimmune hepatitis) occurred in a single individual (2%), whereas autoantibodies were present in 44% of the children. Food allergy and autoantibodies occurred concomitantly in 19% of the children, which was almost twice the frequency expected by chance (11%, P = 0.04). Respiratory allergy and the presence of autoantibodies were unrelated (12% concurrence versus the expected 10%, P = 0.73). In the logistic regression analysis, autoantibody formation was associated with discontinued immunosuppression and food allergy, with odds ratios of 13 (P = 0.01) and 7.1 (P = 0.03), respectively.

CONCLUSIONS

In contrast to respiratory allergy, food allergy and autoantibody formation occurred together in the same children who underwent liver transplantation at a frequency higher than would be expected by chance. This may reflect an underlying immune dysregulation that impairs immune tolerance to both food allergens and autoantigens.

Combinatory treatment using tacrolimus and a STAT3 inhibitor regulate Treg cells and plasma cells

Systemic lupus erythematosus (SLE; lupus) is a prototypical autoimmune disease characterized by circulating autoantibodies to nuclear antigens and immune complex deposition, resulting in damage to target organs. To investigate the effects of tacrolimus (TAC) on effector T cells and B cells, we examined its involvement in the development of effector T cells, germinal center (GC) B cells, and plasma cells in an in vitro system using wild-type (WT) and lupus-prone mice. The population of T helper (Th) 1, Th2, and Th17 cells interleukin (IL)-17-producing T (Th17) cells and the production of interferon-γ and interleukin-17A IL-17A were suppressed by TAC. TAC also reduced the population of regulatory T (Treg) cells; however, a combination treatment with the signal transducer and activator of transcription 3 (STAT3) inhibitor STA-21 promoted the population of Treg cells. TAC also suppressed the populations of GC B cells and plasma cells synergistically with STA-21. These findings suggest that the application of TAC with a STAT3 signal inhibitor may provide benefits in SLE treatment.

Promoter polymorphisms of the TIM-4 gene are correlated with disease activity in patients with systemic lupus erythematosus

Although the TIM gene family plays important roles in immune responses, little is known about TIM regulation in the development of systemic lupus erythematosus (SLE). This study aimed to investigate the association of two TIM-4 single nucleotide polymorphisms (SNPs) rs6874202 (-1419G>A) and rs62382402 (-1609G>A) with SLE susceptibility in a Chinese Han population. The results showed no significant differences between patients with SLE and control group for rs6874202 and rs62382402 (p = .72, .53 respectively). However, the anti-dsDNA levels in serum from SLE patients with GG genotype of TIM-4 gene at -1419 site were significantly higher than those with GA and AA genotype (p = .0335), and C3 levels of SLE patients with GG and GA genotype were much lower than those with AA genotypes (p = .0187). Moreover, the apoptotic cell levels of SLE patients with AA and GG genotypes were significantly higher than those with GA genotypes in patients with SLE (p = .0393). In addition, the C3 concentration of SLE patients with the GG genotype of TIM-4 gene at -1609 site was found to be significantly higher than those with the GA genotype (p = .0129). The results imply that GG genotype of the TIM-4 gene at -1419 site might be associated with the disease activity of SLE.

The constant region affects antigen binding of antibodies to DNA by altering secondary structure

We previously demonstrated an important role of the constant region in the pathogenicity of anti-DNA antibodies. To determine the mechanisms by which the constant region affects autoantibody binding, a panel of isotype-switch variants (IgG1, IgG2a, IgG2b) was generated from the murine PL9-11 IgG3 autoantibody. The affinity of the PL9-11 antibody panel for histone was measured by surface plasmon resonance (SPR). Tryptophan fluorescence was used to determine wavelength shifts of the antibody panel upon binding to DNA and histone. Finally, circular dichroism spectroscopy was used to measure changes in secondary structure. SPR analysis revealed significant differences in histone binding affinity between members of the PL9-11 panel. The wavelength shifts of tryptophan fluorescence emission were found to be dependent on the antibody isotype, while circular dichroism analysis determined that changes in antibody secondary structure content differed between isotypes upon antigen binding. Thus, the antigen binding affinity is dependent on the particular constant region expressed. Moreover, the effects of antibody binding to antigen were also constant region dependent. Alteration of secondary structures influenced by constant regions may explain differences in fine specificity of anti-DNA antibodies between antibodies with similar variable regions, as well as cross-reactivity of anti-DNA antibodies with non-DNA antigens.

Selective sequestration of STAT1 in the cytoplasm via phosphorylated SHP-2 ameliorates murine experimental colitis

The side effects of current immunosuppressive drugs have impeded the development of therapies for immune diseases. Selective regulation of STAT signaling is an attractive strategy for treating immune disorders. In this study, we used a small-molecule compound to explore possible means of targeting STAT1 for the treatment of Th1-mediated inflammation. Selective regulation of STAT1 signaling in T cells from C57BL/6 mice was accomplished using fusaruside, a small-molecule compound that triggers the tyrosine phosphorylation of Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2). The interaction of tyrosine phosphorylated SHP-2 (pY-SHP-2) with cytosolic STAT1 prevented the recruitment of STAT1 to IFN-γR and specifically inhibited STAT1 signaling, resulting in a reduction in Th1 cytokine production and an improvement in 2, 4, 6-trinitrobenzene sulfonic acid-induced colitis in mice. Blocking the pY-SHP-2-STAT1 interaction, with SHP-2 inhibitor NSC-87877 or using T cells from conditional SHP-2 knockout mice, reversed the effects of fusaruside, resulting in STAT1 activation and worsened colitis. The fusaruside-induced ability of pY-SHP-2 to selectively sequestrate STAT1 from recruitment to the receptor is independent of its function as a phosphatase, demonstrating a novel role for SHP-2 in regulating both STAT1 signaling and Th1-type immune responses. These findings could lead to increased options for the treatment of Crohn's disease and other Th1-mediated inflammatory diseases.

Tacrolimus versus cyclophosphamide as treatment for diffuse proliferative or membranous lupus nephritis: a non-randomized prospective cohort study

Treatment of lupus nephritis (LN) with cyclophosphamide (CYC) is effective but retains a certain severe adverse effect. Tacrolimus (TAC) may be a suitable treatment for LN. Forty patients with diffuse proliferative or membranous LN were recruited for this non-randomized open-label study — 67.5% (27/40) had nephrotic proteinuria (>3.5 g/day) and 50.0% (20/40) had low estimated glomerular filtration rate (eGFR) (<60 mL/min/1.73m2). We compared the efficacy and adverse effects of TAC (0.04–0.08 mg/kg/d)/prednisone for 12 months (TAC group, n = 20) with intravenous CYC (750 mg/m2 per month)/prednisone for six months followed by azathioprine (Aza) (100 mg/day)/prednisone for six months (CYC group, n = 20). The TAC target concentration was 6–8 ng/mL or 4–6 ng/mL, respectively, when induction or maintenance therapy was required and 4.0 ng/mL for patient with renal insufficiency. In the TAC group, mean urinary protein excretion decreased significantly from 5.00 ± 1.91 g/day at baseline to 2.54 ± 1.68 g/day after two weeks of therapy ( P < 0.001), compared with the CYC group (4.9 ± 19.4 g/day), P = 0.001, and 65.0% (13/20) achieved partial remission at one month, compared with the CYC group (0/20), P < 0.001. The incidence of complete remission (CR) was significantly higher in the TAC group than in the CYC group (55.0% vs.15.0% by five months, P = 0.008, and 75.0% vs.40.0% by 12 months, P = 0.025, respectively). The significant improvement in serum anti-dsDNA and systemic lupus erythematosus (SLE) disease activity index (DAI) was in the TAC group relative to the CYC group at 12 months ( P = 0.031, P = 0.003, respectively). The eGFR improved in the TAC group from 59.90 ± 23.64 mL/min/1.73m2 at baseline to 93.75 ± 28.52 mL/min/1.73m2 after 12 months, P = 0.001. In the CYC group, two patients developed end-stage renal disease (ESRD), three patients experienced serious pneumonia, and one patient died. Our preliminary study showed TAC is a safe and effective treatment for LN with severe renal disease, and with less-severe adverse events compared with CYC followed Aza therapy. Further larger sample studies are needed to confirm our conclusion.

Therapeutic strategies for SLE involving cytokines: mechanism-oriented therapies especially IFN-gamma targeting gene therapy

Systemic lupus erythematosus (SLE: lupus) is a chronic complicated autoimmune disease and pathogenesis is still unclear. However, key cytokines have been recognized. Interferon (IFN)-γ and also IFNalpha/beta are of particular importance. Depending on the concept that lupus is a helper T(Th)1 disease and that dendritic cells (DCs) determine the direction of lupus, balance shift of Th1/Th2 and immunogenic/tolerogenic DCs is reviewed for therapy. (IFN)-gamma- and IFN-alpha/beta-targeted (gene) therapies are introduced. These consist of Th1/Th2 balance shift and elimination of IFN-gamma and IFN-gamma-related cytokines such as (interleukin)IL-12 and IL-18. Other approaches include suppression of immunocompetent cells, normalization of abnormal T-cell function, costimulation blockade, B lymphocyte stimulator (Blys) blockade, and suppression of nephritic kidney inflammation. Moreover, balance shift of IFN-alpha/beta and tumor necrosis factor (TNF)-alpha together with regulatory T(Treg) cells are briefly introduced. Clinical application will be discussed.

Efficacy and cytokine modulating effects of tacrolimus in systemic lupus erythematosus: a review

Systemic lupus erythematosus (SLE) is a complex systemic autoimmune disease with involvement of both B cells and cytotoxic T lymphocytes and several cytokines aberrations. Standard therapy for SLE has its limitations. Tacrolimus, a novel calcineurin inhibitor with potent immunosuppressive effects, has been shown in the recent years to be effective in SLE therapy. This paper serves to collate the experimental and clinical data on the efficacy of tacrolimus in the treatment of SLE and lupus nephritis. Tacrolimus as a key component of multitarget therapy in SLE is also discussed. The immunocytokine modulatory effects of tacrolimus are also reviewed with reference to SLE. It can be concluded that tacrolimus has an established role in the management of SLE.

Clinical efficacy and cytokine network-modulating effects of tacrolimus in myasthenia gravis

To clarify the long-term efficacy, safety and the cytokine network-modulating effects of tacrolimus in myasthenia gravis, medical records of 86 newly diagnosed consecutive patients and nine steroid-dependent patients were retrospectively reviewed, and peripheral blood mononuclear cells (PBMC) were cultured for the cytokine profile. Steroid reduction effects were observed by using tacrolimus, and no serious adverse effects were observed. The culture study showed reduced IL-12, IL-17, IFN-gamma, GM-CSF, TNF-alpha and MIP-1beta, and elevated IL-10 in the PBMC from patients who received tacrolimus, which suggests inhibition of T cells and macrophages, and enhancement of type 1 regulatory T cells.

T cell cytokine imbalance towards production of IFN-gamma and IL-10 in NZB/W F1 lupus-prone mice is associated with autoantibody levels and nephritis

OBJECTIVE

The role of T cell-derived cytokine production in lupus is poorly understood. We analysed the cytokine production of CD4(+) T cells in the NZB/W F1 mouse strain, the mouse model probably most closely resembling human systemic lupus erythematosus (SLE), and assessed whether a possible shift in the cytokines expressed is associated with age or disease activity.

METHODS

We used intracellular cytokine staining and flow cytometry to determine the cytokine expression of splenic CD4(+) T cells for interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), interleukin-4 (IL-4) and IL-10. NZB/W F1 mice at different ages spanning 5 to 36 weeks were analysed, healthy Balb/cxNZW F1 (CWF1) mice were used as controls. Serum anti-double-stranded DNA (anti-dsDNA) antibody levels were determined by enzyme-linked immunosorbent assay (ELISA), and proteinuria and plasma creatinine were estimated using commercial test kits.

RESULTS

The cytokine profile of CD4(+) T cells was shifted towards T-helper 1 (Th1) cells and the frequencies of Th cells expressing IFN-gamma(+) correlated with age, anti-dsDNA-immunoglobulin G (IgG) titre and proteinuria. An increased percentage of IL-10 producers correlated positively with anti-dsDNA-IgG and proteinuria, and a small gain in IL-4 producers correlated with plasma creatinine. Neither the percentage of IL-10 producers nor IL-4 producers showed a significant correlation with age. There was no significant change observed in the frequency of TNF-alpha T cells. The IFN-gamma/IL-4 ratio demonstrated an increasing shift towards a Th1-type response during disease development that was not present in healthy mouse strains.

CONCLUSION

The association between the frequencies of T cells expressing IFN-gamma and IL-10 and clinical findings suggests a key role for these cells in the pathogenesis of lupus.

FK506 Controls CD40L-Induced Systemic Autoimmunity in Mice

Autoimmunity results from loss of mechanisms controlling self-reactivity. Autoimmune disorders play an increasingly important role and CD40-CD40 ligand (CD40L) interaction on immunocompentent cells is able to break established immunotolerance. To study the effects of the calcineurin-inhibitor FK506 on CD40L-induced systemic autoimmunity, CD40L transgenic (tg) mice, which spontaneously develop a mixed connective tissue-like disease, were treated with FK506 after onset of overt autoimmunity. Interestingly, FK506-treated CD40L tg mice showed significantly reduced autoimmune dermatitis scores and markedly decreased numbers of lesional infiltrating leukocytes. This finding was associated with diminished lymphadenopathy induced by FK506 treatment. Furthermore, FK506 suppressed the development of cytotoxic/autoreactive CD8(+) T cells as evidenced by the reduced expression of T cell activation markers in treated CD40L tg mice. Importantly, FK506 induced a significant reduction in autoantibody titers in the serum of CD40L tg animals. As CD40L tg mice develop nephritis leading to loss of renal function proteinuria was determined after FK506 injections. Notably, FK506 treatment re-established renal function as indicated by significantly reduced uric protein concentrations of treated CD40L tg mice. Together, these findings show the beneficial therapeutic effects of FK506 for the treatment of CD40L-induced autoimmunity. Additionally, these results demonstrate that FK506 is able to suppress ongoing severe autoimmune responses.