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OBJECTIVE--Coinhibitory signals mediated via programmed death 1 (PD-1) receptor play a critical role in downregulating immune responses and in maintaining peripheral tolerance. Programmed death 1 ligand 1 (PD-L1), the interacting ligand for PD-1, widely expressed in many cell types, acts as a tissue-specific negative regulator of pathogenic T-cell responses. We investigated the protective potential of PD-L1 on autoimmune diabetes by transgenically overexpressing PD-L1 in pancreatic p-cells in nonobese diabetic (NOD) mice. RESEARCH DESIGN AND METHODS--We established an insulin promoter-driven murine PD-L1 transgenic NOD mouse model to directly evaluate the protective effect of an organ-specific PD-L1 transgene against autoimmune diabetes. Transgene expression, insulitis, and diabetic incidence were characterized in these transgenic NOD mice. Lymphocyte development, Th1 cells, and regulatory T-cells were analyzed in these transgenic mice; and T-cell proliferation, adoptive transfer, and islet transplantation were performed to evaluate the PD-L1 transgene-mediated immuneprotective mechanisms. RESULTS--The severity of insulitis in these transgenic mice is significantly decreased, disease onset is delayed, and the incidence of diabetes is markedly decreased compared with littermate controls. NOD/SCID mice that received lymphocytes from transgenic mice became diabetic at a slower rate than mice receiving control lymphocytes. Moreover, lymphocytes collected from recipients transferred by lymphocytes from transgenic mice revealed less proliferative potential than lymphocytes obtained from control recipients. Transgenic islets transplanted in diabetic recipients survived moderately longer than control islets. CONCLUSIONS--Our results demonstrate the protective potential of transgenic PD-L1 in autoimmune diabetes and illustrate its role in downregulating diabetogenic T-cells in NOD mice. Diabetes 57:1861-1869, 2008, Programmed death 1 (PD-1) is an immunoreceptor of the CD28/CTLA-4 family whose expression is induced in activated T- and B-cells and in macrophages (1,2). PD-1 has two cytoplasmic tyrosine motifs: [...]

Study objectives: In this study, we determined the effects of various body temperatures (BTs) after initiation of lipopolysaccharide (LPS)-induced lung injury. Design and setting: Forty-nine, adult, male, Sprague-Dawley rats each [...]

The mechanism by which some herbal medicines reduce inflammation may be the targeting of endothelial cellular adhesion molecules and also those of leucocytes. In testing Tripterygium Wilfordii Hook-f (TWH-f) and Tetrandine, endothelial cells, synovial fibroblasts and human neutriphils were each incubated with varying concetnrations of TWH-f with or without interleuken 1. TWH-f had a significant effect inhibitin secretion and expression of cellular adhesion molecules. The tetrandine did not have as marked an effect.

To explore associations between obstructive sleep apnea (OSA) and autoimmune diseases and evaluate whether OSA management reduces the incidence of autoimmune diseases.

The differential activation of T helper (Th) cells and production of cytokines contribute to graft rejection or tolerance. In general, the Th1-type cytokines and cytotoxic T-cells are detected consistently in a host who is undergoing rejection, whereas Th2 responses are linked to a tolerance condition. Galectin-9 modulates Th1 cell immunity by binding to the T-cell immunoglobulin mucin-3 (Tim-3) molecule expressed on the Th1 cells. We investigate whether overexpression of galectin-9 in islets prolongs grafts survival in diabetic recipients. Islets were transduced with lentiviruses carrying galectin-9 and were then transplanted to streptozotocin-induced diabetic NOD/SCID recipients. The normoglycemic recipients then received splenocytes from diabetic NOD mice. Blood glucose concentration was monitored daily after adoptive transfer. The histology of the islet grafts and flow cytometric analyses were assessed at the end of the study. Overexpression of galectin-9 in islets prolonged graft survival in NOD/SCID mice after challenge with diabetogenic splenocytes (mean graft survival, 38.5 vs. 26.0 days, n= 10, respectively; p= 0.0096). The galectin-9-overexpressed grafts showed decreased infiltration of IFN-γ-producing CD4+and CD8+T-cells, but not of IL-17-producing CD4+T-cells. Strikingly, this islet-specific genetic manipulation did not affect the systemic lymphocyte composition, indicating that galectin-9 may regulate T-cell-mediated inflammation in situ. We demonstrate that galectin-9 protects grafts from Th1 and Tc1 cellmediated rejections, suggesting that galectin-9 has preventive and/or therapeutic benefit in transplant therapy for autoimmune diabetes and may be applied further to the transplantation of other organs or tissues.

OBJECTIVE: To investigate the immune-modulated effects of decoy receptor 3 (DCR3) in an experimental model of rheumatoid arthritis (RA). METHODS: We delivered DCR3 plasmid into collagen-induced arthritis (CIA) mice using the hydrodynamic method and evaluated the serum level of DCR3 protein by ELISA. After immunization, we assessed disease severity of arthritis incidence, arthritis scores, paw thickness, and means of arthritic limbs, and used hematoxylin and eosin staining to observe synovial hyperplasia. We analyzed numbers of murine splenocytes and inguinal lymphocyte cells, cell populations, and serum proinflammatory cytokines by flow cytometry. We investigated B cell proliferation by carboxyfluorescein succinimidyl ester assay. We evaluated serum levels of total IgG2a and type II collagen-specific IgG and IgG2a using ELISA. RESULTS: DCR3 expression in sera significantly attenuated disease severity in CIA mice. We found that DCR3 inhibited the volume of inguinal lymph nodes, numbers of CD19+ B cells, and populations of interferon-γ, interleukin 4 (IL-4), IL-17A, and Foxp3-producing CD4+ T cell in vivo. We found that DCR3 inhibited Pam3CSK4 (Toll-like receptor 1/2 ligand)-induced B220+ B cell proliferation in vitro. DCR3 treatment reduced the serum level of IL-6, total IgG2a, and CII-specific IgG2a antibody. CONCLUSION: We postulated that the protective effects of DCR3 in CIA resulted from modulation of the immune system by maintaining the B/T cell balance and decreasing lymphocyte expansion. We suggest DCR3 as a prophylactic and potential therapeutic agent in the treatment of RA.

OBJECTIVE: Plectranthus amboinicus has been known to treat inflammatory diseases or swelling symptoms. We investigated whether P. amboinicus exhibited an inhibitory effect on osteoclastogenesis in vitro and inflammatory bone erosion in collagen-induced arthritis (CIA) mice, an animal model of rheumatoid arthritis. We attempted to identify the active component of P. amboinicus involved in regulation of osteoclastogenesis. METHODS: We treated M-CSF- and RANKL-stimulated murine bone marrow-derived macrophages (BMM) and RANKL-induced RAW264.7 cells with different concentrations of P. amboinicus or rosmarinic acid, a phytopolyphenol purified from P. amboinicus, to monitor osteoclast formation by TRAP staining. The mechanism of the inhibition was studied by biochemical analysis such as RT-PCR and immunoblotting. CIA mice were administered gavages of P. amboinicus (375 mg/kg) or placebo. Then clinical, histological, and biochemical measures were assessed to determine the effects of P. amboinicus on synovial inflammation and bone erosion by H&E staining of the inflamed joints and ELISA. RESULTS: Rosmarinic acid strongly inhibited RANKL-induced NF-κB activation and nuclear factor of activated T cells c1 (NFATc1) nuclear translocation in BMM, and also inhibited RANKL-induced formation of TRAP-positive multinucleated cells. A pit formation assay and the CIA animal model showed that P. amboinicus significantly inhibited the bone-resorbing activity of mature osteoclasts. CONCLUSION: We postulated that rosmarinic acid conferred the inhibitory activity on P. amboinicus for inhibition of osteoclastogenesis via downregulation of RANKL-induced NFATc1 expression. Our results indicated the possibility of P. amboinicus as a new remedy against inflammatory bone destruction.

OBJECTIVE: Imbalance of inflammatory and antiinflammatory cytokines plays a critical role in the pathogenesis of rheumatoid arthritis (RA). Precise determination of these cytokines would lead to better understanding of the progression of RA. METHODS: We developed an in vivo microdialysis technique to directly monitor cytokine profiles in knee joints of rats with adjuvant-induced arthritis (AIA). Microdialysates drained from knee joints of rats with AIA and controls were collected and cytokine concentrations were measured by ELISA. Pathological changes of the knee joints and the source of monocyte chemoattractant factor–1 (MCP-1) secretion were also determined by histology and immunohistochemistry. RESULTS: MCP-1 expression in knee joints was significantly higher in AIA rats with erosive changes in their ankles than in normal rats, while interleukin 6 (IL-6) levels were similar in both cases. IL-1β and interferon-g were not detectable in the microdialysates. Increased synovial proliferation and mononuclear inflammatory infiltrates were observed. Synovial cells and mononuclear inflammatory cells expressed both MCP-1 and its receptor, CCR2. CONCLUSION: Our results indicate that the in vivo microdialysis technique is capable of detecting cytokines in the knee joints of rats. Increased expression of MCP-1 and CCR2 in knee joints of AIA rats suggests a role for this cytokine in triggering the mechanisms involved in the pathogenesis of knee joint after ankle erosion.

Chronic inflammation is one of the important mechanisms involved in atherosclerosis formation. The activated monocytes and their secreted cytokines contribute significantly to this inflammatory process. Here we examined the effects of carvedilol, a recently introduced cardio-protective alpha-1- and beta-receptor blocker, on cytokine production from various stimuli-activated human immune effector cells. By ELISA analysis, we showed that carvedilol inhibited interferon-gamma (IFN-γ), but enhanced interleukin (IL)-12 production in phytohemagglutinin (PHA)- and concanavalin A (ConA)-stimulated human peripheral blood mononuclear cells (PBMCs). The production of tumor necrosis factor-alpha (TNF-α) was marginally affected. When purified monocytes were examined, we observed the consistent up-regulation of IL-12 production while both IL-10 and TNF-α were unaffected or marginally down-regulated, respectively, by carvedilol. In agreement with the observation in monocytes, the production of IL-12 from activated macrophages was also up-regulated by carvedilol. We concluded that carvedilol might mediate its therapeutic effects through differentially regulating cytokine production from activated mononuclear cells, including at least monocytes and macrophages.

To evaluate the efficacy and tolerability of dehydroepiandrosterone (DHEA) at a dosage of 200 mg/day in adult women with active systemic lupus erythematosus (SLE). In a multicenter randomized, double-blind, placebo-controlled trial, 120 adult women with active SLE received oral DHEA (200 mg/day; n = 61) or placebo (n = 59) for 24 weeks. The primary end point was the mean change from baseline in the Systemic Lupus Activity Measure (SLAM) score at 24 weeks of therapy. Secondary end points included time to first flare, change in SLE Disease Activity Index (SLEDAI) score, and physician's and patient's global assessment scores at week 24. The two groups were well balanced for baseline characteristics. Mean reductions in SLAM scores from baseline were similar and were not statistically significantly different between treatment groups (DHEA −2.6 ± 3.4 versus placebo −2.0 ± 3.8, mean ± SD). The number of patients with flares was decreased by 16% in the DHEA group (18.3% of DHEA-treated patients versus 33.9% of placebo-treated patients; P = 0.044, based on time to first flare). The mean change in the patient's global assessment was statistically significant between the two groups (DHEA −5.5 versus placebo 5.4; P = 0.005). The number of patients with serious adverse events, most of which were related to SLE flare, was significantly lower in DHEA-treated patients compared with placebo-treated patients (P = 0.010). Expected hormonal effects, including increased testosterone levels and increased incidence of acne, were observed. No life-threatening reactions or serious safety issues were identified during this study. The overall results confirm that DHEA treatment was well-tolerated, significantly reduced the number of SLE flares, and improved patient's global assessment of disease activity.

Graft versus host disease (GVHD) remains the major obstacle to the widespread application of allogeneic bone marrow transplantation (BMT) despite improvement in drug prophylaxis. T cells in the donor bone marrow recognize and react against host alloantigens and thereby initiate GVHD, but the precise mechanisms by which host tissues are damaged remain unclear. In the current study, we determined the cytokine secretion, cell population distribution, and cell surface markers expression by ELISA and flow cytometer, to understand further the pathophysiology of GVHD. Our results demonstrated that there was no significant change in the cell ratio of B-and T- lymphocytes, and helper/suppressor cells during GVHD development when compared to the condition before transplantation. Furthermore, the percentage of natural killer cells, the interleukin-2 receptor (IL-2R) or the HLA-DR antigen on both CD4 and CD8 positive cells presented no significant difference between pre-transplantation and during GVHD. The serum cytokine secretion of IL-1, TNF-alpha, IL-2, ICAM-1, endothelin, TGF-beta showed no difference before BMT and during GVHD. However, when patients in the developing of GVHD, there was significant difference in the serum levels of soluble IL-2R (sIL-2R), epidermal growth factor (EGF), and platelet derived growth factor (PDGF). In addition, with patients who develop GVHD, the mixed lymphocyte reaction also presented a significant difference. This study indicated that some serum cytokines such as sIL-2R. growth factors, and the mixed lymphocyte reaction may be used as parameters for the early detection of the development of GVHD.

T lymphocyte activation mediated by CD28 costimulation plays a critical role in graft rejection. Plant alkaloid tetrandrine, purified from a Chinese antirheumatic herb, is a potent immunosuppressant. Here, we examined its effects on several CD28-costimulated T-cell activities. In addition, such effects were readily compared with the effects of three tetrandrine analogs.

Abstract:: Adverse drug reactions of non-steroidal anti-inflammatory drugs (NSAIDs) are quite prevalent, but there are few reports about possible adverse psychiatric reactions, which may be ignored or underestimated. We describe here five psychiatric outpatients, two with major depressive disorders, one bipolar disorder, one schizophrenic disorder and one anxiety disorder, who were treated with NSAIDs for pain due to rheumatoid arthritis, osteoarthritis or other painful neuromuscular conditions. All five patients developed a moderate to severe depressive state, three patients became obviously paranoid, and four had either thoughts of suicide or an attempt while undergoing co-administration of NSAIDs. The psychiatric symptoms remitted when the NSAIDs were stopped. The depressive and paranoid symptoms returned on seven occasions of re-use or re-challenge with the same or a different type of NSAID in all five patients. When the NSAIDs were stopped again, the patients had another remission of the adverse psychiatric reactions, and eventually recovered to their baseline mental states in clear temporal relationships. The cases presented suggest that NSAIDs can induce or exacerbate idiosyncratic reproducible adverse psychiatric symptoms in certain vulnerable patients, including those with a variety of psychotic or neurotic disorders, and also in elderly persons, but these undesirable side-effects were generally transient and disappeared on withdrawal of the NSAIDs.

1.An intervention to reduce ischaemia–reperfusion lung injury will be an important advance in transplant medicine. Although the mechanisms associated with producing ischaemia–reperfusion endothelial injury have not been completely elucidated, many of the injury mediators have been studied in detail. While no single pharmacological therapy is likely to be totally effective in eliminating this complex injury, we have developed a mixture of agents that are known to block pathways involved in producing ischaemia–reperfusion-associated lung vascular injury. 2.The present study modified University of Wisconsin solution (UW) by adding one of the protective agents prostaglandin E1 (PGE1), dexamethasone (Dex) or dibutyryl cAMP (Bt2-cAMP), or a combination of these, to the perfusate of rat lungs exposed to 4 ;h of cold ischaemia followed by 1 ;h of reperfusion. Nine modified UW solutions were studied: (1) UW+Dex, (2) UW+PGE1, (3) UW+Bt2-cAMP, (4) UW+Dex×3, (5) UW+PGE1×3, (6) UW+Bt2-cAMP×3, (7) UW+Dex+PGE1, (8) UW+Dex+Bt2-cAMP, (9) UW+PGE1+Bt2-cAMP. These solutions were utilized in individual experiments to assess haemodynamic changes, lung weight gain, the capillary filtration coefficient (Kfc) and pathology in all lungs. 3.The results indicate that lung weight gain and Kfc values were significantly lower than with UW alone in groups 1, 2 and 3, which contained only one additional protective agent. In groups 4, 5 and 6, which contain three times the concentration of each protective agent, both Kfc and lung weight gain were similar to those measured in groups 1, 2 and 3, i.e. lungs were protected but the protection was not dose dependent. In groups 7, 8 and 9, which contained two protective agents, lung weight gain and Kfc were greatly reduced compared with UW alone. Histopathological studies showed similar decreases in the injury profiles of lungs. 4.Although UW contains several antioxidant protective agents such as allopurinol and glutathione, it did not provide effective protection in our ischaemia–reperfusion lung injury model. UW modified with an additive of PGE1, Dex or Bt2-cAMP attenuated ischaemia–reperfusion injury. Furthermore, UW containing two of these protective agents augmented the protection. Among the modified solutions, it appears that UW+PGE1+Bt2-cAMP protects the lungs to a greater extent than all other solutions used in our study. We suggest that preservation solutions containing PGE1-Bt2-cAMP will provide additional protective effects to organs stored for transplantation.

Chiang, Chi-Huei, Kang Hsu, Horng-Chin Yan, Horng-Jyh Harn, and Deh-Ming Chang.PGE1, dexamethasone, U-74389G, or Bt2-cAMP as an additive to promote protection by UW solution in I/R injury.J. Appl. Physiol.83(2): 583–590, 1997.—A method to reduce ischemia-reperfusion (I/R) injury can be an important criterion to improve the preservation solution. Although University of Wisconsin solution (UW) works as a lung preservation solution, its attenuation effect on I/R injury has not been investigated. We attempted to determine whether, by adding various protective agents, modified UW solutions will enhance the I/R attenuation by UW. We examined the I/R injury in an isolated rat lung model. Various solutions, e.g., physiological salt solution (PSS), UW, and modified UW solutions containing various protective agents such as prostaglandin E1, dexamethasone, U-74389G, or dibutyryl adenosine 3′,5′-cyclic monophosphate were perfused individually to evaluate the I/R injury. Isolated rat lung experiments, with ischemia for 45 min, then reperfusion for 60 min, were conducted in a closed circulating system. Hemodynamic changes, lung weight gain (LWG), capillary filtration coefficient (Kfc), protein content of lavage fluid, concentration of cytokines, and lung histopathology were analyzed. Results showed that the acute I/R lung injury with immediate permeability pulmonary edema was associated with an increase in tumor necrosis factor-α (TNF-α) production. A significant correlation existed between TNF-α and Kfc(r= 0.8,P< 0.0001) and TNF-α and LWG (r= 0.9,P< 0.0001), indicating that TNF-α is an important cytokine modulating early I/R injury. Significantly lower levels ofKfc, LWG, TNF-α, and protein concentration of lung lavage (P< 0.05) were found in the UW-perfused group than in the control group perfused with PSS. Modified UW promoted the protective effect of UW to further decreaseKfc, LWG, and TNF-α (P< 0.05). Histopathological observations also substantiated this evidence. In the UW+U-74389G group, bronchial alveolar lavage fluid contained lowest protein concentration. We conclude that the UW solution attenuates I/R injury of rat lung and that the modified UW solutions further enhance the effect of UW in reducing I/R injury. Among modified solutions, UW+U-74389G is the best. Further investigation of the improved effects of the modified UW solutions would be beneficial in lung transplantation.

The polypeptide cytokine interleukin-1 (IL-1) mediates a broad spectrum of inflammatory, metabolic, physiologic, hematopoietic, and immunologic properties. An inhibitor of IL-1 (IL-1ra) has been purified from monocytes, and its DNA has been cloned. Human immunoglobulin G stimulates monocytes to make IL-1ra, but the monocyte receptor(s) for this induction remains a mystery. Therefore, the cellular Fc receptors (FcγR) for IgG that induce IL-1ra production were tested. The FcγR were defined and quantitated by flow cytometer. Anti-FcγRIII (CD16), anti-FcγRII (CD32), and anti-FcγRI (CD64) had no blocking effect on IL-1ra production from monocytes after IgG stimulation. Monocytes express FcγRI and II and respond as anti-CD32 to secrete IL-1ra; neutrophils express FcγRII and III and respond as anti-CD16 to secrete IL-1ra; macrophages express FcγRI, II, and III and respond as both anti-CD16 and anti-CD32 to secrete IL-1ra. These studies strongly suggested that both Fcγ receptor II and III play a key role in IL-1ra production.

Accumulation of advanced glycation end products (AGEs) in joints contributes to the pathogenesis of cartilage damage in osteoarthritis (OA). We aim to explore the potential chondroprotective effects of resveratrol on AGEs-stimulated porcine chondrocytes and cartilage explants.