Modified BuShenYiQi formula alleviates experimental allergic asthma in mice by negative regulation of type 2 innate lymphoid cells and CD4+ type 9 helper T cells and the VIP-VPAC2 signalling pathway.

CONTEXT: Modified BuShenYiQi formula (M-BYF) is derived from BuShenYiQi formula, used for the treatment of allergic asthma. The exact effect and mechanism of M-BYF on the improvement of asthma remain unclear. OBJECTIVE: We investigated the mechanism underlying the therapeutic effect of M-BYF on allergic asthma. MATERIALS AND METHODS: The asthma model was established in female BALB/c mice that were sensitized and challenged with ovalbumin (OVA). Mice in the treated groups were orally treated once a day with M-BYF (7, 14 and 28 g/kg/d) or dexamethasone before OVA challenge. Control and Model group received saline. Pathophysiological abnormalities and percentages of lung type 2 innate lymphoid cells (ILC2s) and Th9 cells were measured. Expression levels of type 2 cytokines and transcription factors required for these cells function and differentiation were analysed. Expression of vasoactive intestinal polypeptide (VIP)-VPAC2 signalling pathway-related proteins, and percentages of VIP expressing (VIP+) cells and VPAC2, CD90 co-expressing (VPAC2+CD90+) cells were detected. RESULTS: M-BYF alleviated airway hyperresponsiveness, inflammation, mucus hypersecretion and collagen deposition in asthmatic mice. M-BYF down-regulated percentages of ILC2s and Th9 cells with lower expression of GATA3, PU.1 and IRF4, reduced IL-5, IL-13, IL-9 and VIP production. The decrease in the expression of VIP-VPAC2 signalling pathway and percentages of VIP+ cells, VPAC2+CD90+ cells were observed after M-BYF treatment. The LD50 value of M-BYF was higher than 90 g/kg. DISCUSSION AND CONCLUSIONS: M-BYF alleviated experimental asthma by negatively regulating ILC2s and Th9 cells and the VIP-VPAC2 signalling pathway. These findings provide the theoretical basis for future research of M-BYF in asthma patient population.

Arsenic trioxide plus cisplatin/interferon α-2b/doxorubicin/capecitabine combination chemotherapy for unresectable hepatocellular carcinoma.

BACKGROUND AND OBJECTIVES: The failure of existing treatments for liver cancer has recently been attributed to the existence of cancer stem cells, which are difficult to kill using current drugs due to their chemoresistant properties as well as their ability to stimulate neoangiogenesis. The aim of the current study was to evaluate in vitro the antitumor efficacy of arsenic trioxide in combination with conventional chemotherapy, as proposed by the concept of "differentiation therapy" in anticancer research. MATERIALS AND METHODS: Cancer stem cells showed enhanced chemoresistance to cancer drugs (carboplatin and doxorubicin) and had the ability to exclude rhodamine 123 dye, proving the existence of the multidrug resistance efflux pump. Arsenic trioxide was added prior to a tyrosine kinase inhibitor or to a slightly modified PIAF regimen with capecitabine replacing 5-fluorouracil. We also compared both cancer and normal stem cell lines with the hepG2 non-stem liver cancer cell line to investigate the differences between differentiated and more anaplastic cells. Molecular characterization (immunocytochemistry and RT-PCR analysis) of all the cell lines was carried out. RESULTS: Initially, the cells had a high proliferative potential, even when cultured in a medium supplemented with cytostatics, eliminated rhodamine 123 immediately in culture and also formed spheroids in suspension. The molecular characterization showed the expression of albumin, α1-antitrypsin, α-fetoprotein, citokeratin-18, telomerase, CD90 and CD133. Low concentrations of arsenic trioxide lead to morphologic differentiation and differentiation-associated cytochemical features, like increased sensitivity to cytostatic drugs. CONCLUSION: Our study suggests that arsenic trioxide sensitizes liver stem-like cancer cells to conventional chemotherapy. Still, further studies on animal models will be needed before we implement this idea in human clinical trials.

Effects of TJN-598, a new selective phosphodiesterase type IV inhibitor on anti-Thy1 nephritis in rats.

BACKGROUND: Phosphodiesterase type IV (PDEIV) plays an important role in the immune response and inflammation. However, it is well known that classical PDEIV inhibitors have systemic side effects, so the clinical and chronic use of these agents as therapy for glomerulonephritis is difficult. This study was performed to elucidate the anti-nephritic effects of TJN-598, a new chemical compound derived from herbal components, on experimental mesangial proliferative glomerulonephritis. METHODS: We first examined the effects of TJN-598 and captopril on mesangial expansion induced by anti-Thy1 serum in rats. Second, to investigate the effects of TJN-598 and rolipram, which are typical PDEIV inhibitors, on the production of tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-ß1, glomeruli were isolated from rats with anti-Thy1 nephritis and incubated with the test drugs in vitro for 48 h. RESULTS: Treatment with TJN-598 prevented an increase in the mesangial area/total glomerular area, in the number of cells in the glomerular cross section and matrix index. TJN-598 also inhibited the increases in the expression of α-smooth muscle actin, the TGF-ß1-positive area, in the number of ED-1 positive cells and proliferating cell nuclear antigen-positive cells in the glomeruli. Furthermore, administration of TJN-598 inhibited increases in the levels of TGF-ß1 protein derived from glomeruli with anti-Thy-1 nephritis. The addition of both TJN-598 and rolipram to the culture supernatant inhibited both increased expression of TGF-ß1 and increases in levels of TNF-α in glomeruli isolated from rats with anti-Thy1 nephritis in a dose-dependent manner. CONCLUSION: These results suggest that TJN-598, a PDEIV inhibitor, is effective against expansion of mesangial cells, via the suppression of secretion of TGF-ß1 and TNF-α from inflamed glomeruli.

Ag-specific type 1 CD8 effector cells enhance methotrexate-mediated antitumor responses by modulating differentiated T cell localization, activation and chemokine production in established breast cancer.

The chemotherapeutic agent methotrexate is widely used in the treatment of breast cancer. Although its mechanism-of-action has been defined, less is known about its interaction with T cell-mediated antitumor responses. Type 1 CD8 T cell-mediated immune responses (Tc1) are cytolytic, produce IFN-gamma and are associated with effective antitumor responses. Using a murine transgenic TCR tumor model, we show that single-dose treatment with methotrexate enhanced CD8-mediated type 1 antitumor responses when administered 3 days prior to Tc1 effector cell transfer. Co-treatment with methotrexate not only enhanced donor Tc1 cell accumulation and persistence at sites of primary tumor growth, but also promoted elevated levels of activated donor TIL cells. This markedly enhanced the appearance of endogenous differentiated (CD44(High)) CD8 tumor-infiltrating cells when compared to that of corresponding groups receiving either MTX or Tc1 cell transfer alone. Such cells were acutely activated as defined by co-expression of surface markers associated with TCR engagement (CD69) and T cell activation (CD25) at both early (days 1-8) and late (days 12-20) stages following treatment. Conversely, such animals showed an early decrease in CD4(+)/CD44(High)/CD25(+)/CD69(+) T cells that correlated with delays in tumor growth in vivo. Moreover, cellular response kinetics appeared to further correlate with the up-regulation of endogenous T cells producing the chemokine IP-10 in vivo. This suggested that Tc1 cell transfer, in combination with chemotherapy, can enhance antitumor responses by modulating immunoregulatory T cells involved in homeostasis and immune tolerance within the tumor environment. These studies offer insight into mechanisms that enhance T cell-based immunotherapy in cancer.

Beneficial effect of neutrophil elastase inhibitor on anti-Thy1.1 nephritis in rats.

BACKGROUND: Neutrophil elastase, one of the proteinases released by neutrophils, plays an important role at the sites of inflammation and was reported to be involved in the pathogenesis of glomerulonephritis. Sivelestat is a selective neutrophil elastase inhibitor used for acute lung injury associated with systemic inflammatory response syndrome. There have been few reports on the effects of sivelestat on renal disease. METHODS: In male Wistar rats, anti-Thy1.1 nephritis was induced by the injection of anti-Thy1.1 antibody. The rats were divided into four groups: nephritic rats treated with low- (group A) and high-dose sivelestat (group B), those not treated with sivelestat (group C) and control rats (group D). Urine samples were obtained every day during the experiment. The rats were killed on day 6 in order to obtain the blood plasma and kidneys. Measurement of urine protein levels, blood biochemical values and histological examination of the kidneys were carried out. RESULTS: Increased levels of proteinuria were observed in the nephritic rats (groups A, B and C) compared with group D. The proteinuria level was significantly suppressed by sivelestat in groups A and B in a dose-dependent fashion compared with group C. The light microscopy revealed an increased glomerular cell count in group C, which was significantly suppressed in group B. In the electron microscopic study, sivelestat suppressed the fusion of epithelial foot process, especially in group B. CONCLUSION: Neutrophil elastase is suggested to be involved in the development of anti-Thy1.1 nephritis, and the neutrophil elastase inhibitor sivelestat reduces the tissue injury of anti-Thy1.1 nephritis in rats.

[Nephritic model induced by anti-Thy1.1 monoclonal antibody and its application to study on Chinese materia medica].

The anti-Thy1.1 glomerulonephritis (GN) model induced by anti-Thy1.1 monoclonal antibody (mAb) is a widely used animal model for human mesangial proliferative glomerulonephritis (MsPGN), which is characterized by significant proteinuria and acute or progressive mesangial injury following the complement-mediated mesangiolysis and glomerular inflammatory cell infiltration. In this review, it has been discussed that the pathogenesis of reversible anti-Thy1.1 GN or irreversible anti-Thy1.1 GN induced by mAb 1-22-3 injection, the mechanisms governing inflammatory cells infiltration and several injurious cytokines in glomeruli, and some of the processes involved in the resolution of mesangial lesion such as mesangial cell proliferation and matrix expansion. Using these models, it has been reported to examine the effects of Chinese materia medica, including multi-glycoside of Tripterygium wilfordii Hook. f. (GTW) and Sairei-to on mesangial damage and proteinuria, and then to clarify the mechanism of these herbs at molecular level by examining the effects on various injurious factors.

[Effects of multi-glycoside of Tripterygium wilfordii Hook. f. on proteinuria and expression of slit diaphragm-associated molecules in rats with anti-thy1.1 glomerulonephritis].

OBJECTIVE: To examine the effect of multi-glycoside of Tripterygium wilfordii Hook. f. (GTW) on proteinuria and expression of slit diaphragm-associated molecules such as nephrin and podocin in glomerulonephritis induced by anti-Thy1.1 antibody (anti-Thy1 . 1 GN). METHODS: Anti-Thy1.1 GN was induced in rats by a single intravenous injection with 500 microg of anti-Thy1.1 mAb 1-22-3. Fourteen rats were randomly divided into 2 groups, the GTW-treated group and vehicle treated group, and sacrificed on day 14 in Experiment 1 or on day 7 in Experiment 2 after induction of Anti-Thy1.1 GN. Daily oral administration of GTW and vehicle as a control was started from 3 days before injection or at the same time of injection to the day of sacrifice in Experiment 1 or 2. Proteinuria was determined during 14 days in Experiment 1 or during 7 days in Experiment 2. From kidneys taken at sacrifice, glomerular morphological changes, glomerular macrophage infiltration, glomerular expression of nephrin and podocin, and its mRNA expression in renal tissue were examined. RESULTS: In Experiment 1, proteinuria and mesangial matrix expansion were significantly attenuated by GTW treatment. No difference in staining intensity of nephrin and podocin in glomeruli was observed between GTW treated group and vehicle treated group on day 14. In Experiment 2, GTW treatment significantly ameliorated proteinuria, mesangial injury and activated macrophage infiltration in glomerulus. In addition, it significantly increased the expression of nephrin and podocin and its mRNA expression in glomeruli on day 7. CONCLUSION: In anti-Thy1.1 GN, the reduced expression of nephrin and podocin may contribute to the development of mesangial injury and proteinuria. The findings suggest that GTW ameliorates not only proteinuria but also mesangial lesions in anti-Thy1 . 1 GN most likely by increasing the expression of nephrin and podocin.

[Preventive effect of multi-glycoside of tripterygium Wilfordii Hook. f. on proteinuria and mesangial injury in experimental mesangial proliferative glomerulonephritis].

OBJECTIVE: To observe the preventive effect of multi-glycoside of Tripterygium Wilfordii Hook. f. (GYW) on proteinuria and mesentery injury in experimental mesangial proliferative glomerulonephritis in vivo. METHODS: The reversible anti-Thyl.1 antibody glomerulo nephritis model of rats was established with monoclonal antibody 1-22-3 and intervened with GTW, and a control group was set up in the same time. Changes of 24h urinary protein excretion, serum creatinine (Scr), blood urea nitrogen (BUN), total plasma protein (TP) and glomerular morphology were observed, and the level of mRNA expression of proliferative factors, including platelet-derived growth factor-BB (PDGF-BB) and transforming growth factor-beta (TGF-beta), in renal tissue was determined. RESULTS: GTW could inhibit proteinuria and mesangial injury in anti-Thyl. 1 antibody nephritis model. The PDGF-BB and TGF-beta mRNA expression in the anti-Thy1.1 antibody nephritis model rats were increased for 2.84 and 1.64 times respectively to those in the normal control group. GTW could down-regulate the over-expression of PDGF-BB mRNA by 33.1%, it was significantly different to that in the control group (P < 0.05). CONCLUSION: GTW could reduce the proteinuria and inhibit mesangial cells proliferation and extracellular matrix deposition, these effects maybe related to the down-regulating of PDGF-BB mRNA expression.

Mycophenolate mofetil slows progression in anti-thy1-induced chronic renal fibrosis but is not additive to a high dose of enalapril.

Tubulointerstitial inflammation and fibrosis are hallmarks of chronic progressive renal diseases. To characterize the functional interaction between cell infiltration and matrix expansion, this study compared the immunosuppressant mycophenolate mofetil (MMF), intended as primarily anti-inflammatory intervention, the angiotensin-converting enzyme inhibitor enalapril, intended as primarily an anti-fibrotic drug, and a combination of both as anticipated anti-inflammatory/anti-fibrotic intervention. The model used was anti-thy1-induced chronic-progressive glomerulosclerosis (cGS) in the rat, where a brief anti-thy1-induced glomerular injury progresses spontaneously toward tubulointerstitial fibrosis and renal insufficiency. cGS was induced by injection of anti-thy1 antibody into uninephrectomized Wistar rats. One week after disease induction, animals were randomly assigned to the following groups: cGS, cGS plus MMF (20 mg.kg body wt(-1).day(-1)), cGS plus high-dose enalapril (12 mg.kg body wt(-1).day(-1)), and cGS plus both. At week 16 after disease induction, MMF or enalapril alone reduced signs of chronic renal disease significantly and similarly compared with the untreated cGS group. Variables measured included proteinuria, blood pressure, tubulointerstitial and glomerular matrix accumulation, expression of transforming growth factor-beta(1), fibronectin, and plasminogen activator inhibitor-1, infiltration of lymphocytes and macrophages, plasma creatinine and urea levels, and glomerular filtration rate. Combined MMF and enalapril treatment was not superior to single therapy. In conclusion, MMF slows the progression of chronic renal fibrosis and renal insufficiency as effectively as high-dose enalapril in the anti-thy1-induced chronic-progressive glomerulosclerosis model. The dual anti-inflammatory/anti-fibrotic intervention does not yield additive renoprotective effects, indicating that MMF and enalapril interfere with similar or very closely related pathways involved in progression of renal disease.

Multi-glycoside of Tripterygium wilfordii Hook f. ameliorates proteinuria and acute mesangial injury induced by anti-Thy1.1 monoclonal antibody.

BACKGROUND/AIMS: Multi-glycoside from Tripterygium wilfordii Hook f. (GTW) is used for various immune and inflammatory diseases including renal diseases represented by mesangial proliferative glomerulonephritis (MsPGN) in China. However, there have been no fundamental studies on the operating mechanism of GTW on MsPGN. The aim of this study is to examine as the first step the effects of GTW on acute injurious process such as mesangial injury and proteinuria in an acute and reversible Thy.1.1 glomerulonephritis (Thy1.1GN) model and then to clarify the action mechanism of GTW at molecular level by examining its effects on various injurious factors in this model. METHODS: Thy1.1 GN was induced in rats by a single intravenous injection with 500 microg of anti-Thy1.1 mAb 1-22-3. Daily oral administration of GTW and vehicle as a control was started from 3 days before injection of mAb to the day of sacrifice in each experiment. Fourteen rats were randomly divided into 2 groups, GTW-treated and vehicle-treated groups, and sacrificed on day 14 in experiment 1 or on day 7 in experiment 2 after induction of Thy1.1 GN. Proteinuria was determined on days 1, 3, 5, 7, 10 and 14 in experiment 1 or on 1, 3, 5 and 7 in experiment 2. From blood and kidneys taken at sacrifice, blood biochemical parameters, mesangial morphological changes, glomerular macrophage infiltration, and glomerular mRNA expression of cytokines were examined. RESULTS: In experiment 1, proteinuria and mesangial matrix expansion were significantly attenuated by GTW treatment. In experiment 2, GTW treatment significantly ameliorated proteinuria, mesangial lesions and macrophage accumulation in glomerulus. In addition, it significantly reduced the glomerular expression of mRNA for PDGF, MCP-1 and IL-2. CONCLUSION: GTW ameliorated not only proteinuria but also mesangial alterations in Thy1.1 GN most likely by reducing expression of injurious cytokines, indicating that GTW has suppressive effects on acute inflammatory changes in glomeruli.

[Therapeutical effects of esculentoside A on rats with MsPGN induced by anti-Thy1.1 antibody].

OBJECTIVE: To observe the therapeutical effects of esculentoside A (EsA) on rats with mesangial proliferative glomerulonephritis (MsPGN) induced by anti-Thy1.1 antibody and make a comparison of the effects between EsA and dexamethasone (DXM). METHODS: Wistar rats with MsPGN induced by anti-Thy1.1 serum (ATS) were randomly divided into 3 groups: EsA group, DXM group, and model group. Moreover, a normal group was used for comparison. The BUN, SCr, urinary protein and renal pathological changes were examined after 7 d treatment with EsA and DXM. RESULTS: The urinary protein, cell count and mesangium area of glomerulus were significantly higher in all modeled groups than in normal group (P<0.001-0.05), and they were significantly lower in the treated groups than in untreated group (P<0.001-0.01). CONCLUSION: The results suggest that EsA is effective for reducing the urinary protein excretion and inhibiting the proliferation process of glomerular mesangium and matrix in rats with MsPGN.

Effects of antioxidants on kidney disease.

Kidney mesangial cells (MCs) and vascular smooth muscle cells (VSMCs) are closely related in terms of origin, microscopic anatomy, histochemistry, and contractility. This relationship suggests a similarity between kidney glomerular sclerosis and atherosclerosis. Vitamin E appears beneficial in the prevention and treatment of coronary disease and also inhibits the proliferation of VSMCs in vitro. We used vitamin E and probucol to treat glomerular sclerosis and MC-proliferative glomerulonephritis (GN) in two animal models of glomerular disease. Using rats, a remnant kidney model accelerated with hyperlipidemia was employed to reflect progressive glomerular sclerosis leading to chronic renal failure, and an anti-thymocyte serum treatment was used to model acute MC-proliferative GN. Supplemental dietary antioxidants suppress MC proliferation and glomerular sclerosis in models of glomerular disease in rats. These results suggest that treatment with antioxidants may be a promising intervention to prevent progression of kidney disease.

Characterization of a transformed rat retinal ganglion cell line.

The purpose of the present study was to establish a rat retinal ganglion cell line by transformation of rat retinal cells. For this investigation, retinal cells were isolated from postnatal day 1 (PN1) rats and transformed with the psi2 E1A virus. In order to isolate retinal ganglion cells (RGC), single cell clones were chosen at random from the transformed cells. Expression of Thy-1 (a marker for RGC), glial fibrillary acidic protein (GFAP, a positive marker for Muller cells), HPC-1/syntaxin (a marker for amacrine cells), 8A1 (a marker for horizontal and ganglion cells) and neurotrophins was studied using reverse transcriptase-polymerase chain reaction (RT-PCR), immunoblotting and immunocytochemistry. One of the retinal cell clones, designated RGC-5, was positive for Thy-1, Brn-3C, Neuritin, NMDA receptor, GABA-B receptor, and synaptophysin expression and negative for GFAP, HPC-1, and 8A1, suggesting that it represented a putative RGC clone. The results of RT-PCR analysis were confirmed by immunocytochemistry for Thy-1 and GFAP. Upon further characterization by immunoblotting, the RGC-5 clone was positive for Thy-1, negative for GFAP, 8A1 and syntaxin. RGC 5 cells were also positive for the expression of neurotrophins and their cognate receptors. To establish the physiological relevance of RGC-5, the effects of serum/trophic factor deprivation and glutamate toxicity were analyzed to determine if these cells would undergo apoptosis. The protective effects of neurotrophins on RGC-5 after serum deprivation was also investigated. Apoptosis was studied by terminal deoxynucleotidyl transferase-mediated fluoresceinated dUTP nick end labeling (TUNEL). Serum deprivation resulted in apoptosis and supplementation with both BDNF and NT-4 in the growth media, protected the RGC-5 cells from undergoing apoptosis. On differentiation with succinyl concanavalin A (sConA), RGC-5 cells became sensitive to glutamate toxicity, which could be reversed by inclusion of ciplizone (MK801). In conclusion, a transformed rat retinal cell line, RGC-5, has certain characteristics of retinal ganglion cells based on Thy-1 and Brn-3C expression and its sensitivity to glutamate excitotoxicity and neurotrophin withdrawal. These cells may be valuable in understanding of retinal ganglion cell biology and physiology including in vitro manipulations in experimental models of glaucoma.

Stimulation of thymocyte proliferation by phosphorothioate DNA oligonucleotides.

DNA is a complex macromolecule the immunological properties of which depend on short sequence motifs called CpG motifs or immunostimulatory sequences (ISS). These sequences are mitogenic for B cells and can stimulate macrophage cytokine production. While these sequences do not directly activate T cells, they can augment effects of stimulation via the TCR. Furthermore, ISS can affect T cells because of macrophage production of IL-12 and IFN-alpha/beta. In these studies, we further evaluated the immune effects of DNA on T cells, testing the possibility that certain T cell populations can respond directly to this stimulus. We therefore tested the in vitro responses of thymocytes to a series of phosphodiester (Po) and phosphorothioate (Ps) oligonucleotides (ODNs) varying in sequence. In in vitro cultures, phosphorothioate ODNs (sODNs) containing CpG motifs induced significant proliferation of murine thymocytes, although phosphodiester compounds lacked activity. The magnitude of stimulation varied with sequences flanking the CpG motifs, as both dA and dT sequences enhanced the stimulatory capacity of the CpG motif. Furthermore, CpG sODNs were strong costimulators of anti-CD3-mediated thymocyte activation, increasing proliferation compared to anti-CD3 in the absence of DNA. This activation was only partially inhibited by cyclosporine A and was not dependent on a calcium influx. Together, these results indicate that phosphorothioate oligonucleotides containing CpG motifs can directly induce thymocyte proliferation as well as augment TCR activation. These observations thus extend the range of actions of CpG DNA and suggest additional mechanisms for its function as an immunomodulatory agent or adjuvant.

Suppressive effects of fish oil on mesangial cell proliferation in vitro and in vivo.

BACKGROUND: Mesangial cell proliferation is a characteristic feature of IgA nephropathy and many other forms of glomerulonephritis. Recent clinical studies have shown that dietary fish oil supplementation retards renal disease progression in patients with IgA nephropathy. The mechanism by which this effect occurs is unknown. METHODS: The anti-Thy 1.1 (ATS) model of mesangial proliferative glomerulonephritis was employed to test the hypothesis that dietary fish oil supplementation reduces mesangial cell proliferation following acute injury. Subcultured rat mesangial cells were used to determine the in vitro effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the primary components of fish oil, on proliferation. RESULTS: Following antithymocyte serum (ATS) administration, proteinuria was significantly decreased in animals treated with fish oil compared with sesame oil-treated controls. In ATS rats given fish oil, there was less mesangial cell and matrix expansion, mesangiolysis, or basement membrane disruption (delta% = -40%). ATS rats receiving fish oil had less glomerular cell proliferation (PCNA-delta% = -50%) and a reduction of alpha-smooth muscle actin expression (delta% = -27%) by mesangial cells. In subcultured rat mesangial cells, DHA, but not EPA, significantly inhibited proliferation. CONCLUSIONS: Fish oil inhibits mesangial cell activation and proliferation in ATS glomerulonephritis, reduces proteinuria, and decreases histologic evidence of glomerular damage. In vitro, the antiproliferative effects of fish oil are more likely related to the action of DHA. We suggest that orally administered fish oil, or purified DHA, may have a suppressive effect in acute phases or relapses of glomerulopathies by inhibiting activation and proliferation of mesangial cells.

Non-CD28 costimulatory molecules present in T cell rafts induce T cell costimulation by enhancing the association of TCR with rafts.

While CD28 functions as the major T cell costimulatory receptor, a number of other T cell molecules have also been described to induce T cell costimulation. Here, we investigated the mechanisms by which costimulatory molecules other than CD28 contribute to T cell activation. Non-CD28 costimulatory molecules such as CD5, CD9, CD2, and CD44 were present in the detergent-insoluble glycolipid-enriched (DIG) fraction/raft of the T cell surface, which is rich in TCR signaling molecules and generates a TCR signal upon recruitment of the TCR complex. Compared with CD3 ligation, coligation of CD3 and CD5 as an example of DIG-resident costimulatory molecules led to an enhanced association of CD3 and DIG. Such a DIG redistribution markedly up-regulated TCR signaling as observed by ZAP-70/LAT activation and Ca2+ influx. Disruption of DIG structure using an agent capable of altering cholesterol organization potently diminished Ca2+ mobilization induced by the coligation of CD3 and CD5. This was associated with the inhibition of the redistribution of DIG although the association of CD3 and CD5 was not affected. Thus, the DIG-resident costimulatory molecules exert their costimulatory effects by contributing to an enhanced association of TCR/CD3 and DIG.

T-cell-activating monoclonal antibodies, reacting with both leukocytes and erythrocytes, recognize the guinea pig Thy-1 differentiation antigen: characterization and cloning of guinea pig CD90.

A glycophosphatidylinositol (GPI)-linked differentiation antigen expressed on guinea pig T and B lymphocytes was identified by several monoclonal antibodies; it has been shown previously that this membrane protein induced strong polyclonal T cell proliferation upon antibody binding and costimulation by PMA. Purification by immunoadsorption and microsequencing revealed that this T-cell-activating protein is the homologue of Thy-1 or CD90. In contrast to the Thy-1 antigen of most other species, guinea pig Thy-1 has a much higher molecular weight, which is due to a more extensive N-linked glycosylation, bringing the molecular weight of the total antigen up to 36 kDa. Molecular cloning of guinea pig Thy-1 indicated that the deduced molecular weight of the protein backbone is 12,777 after removal of an N-terminal 19-amino-acid leader peptide and cleavage of the 31 amino acids for GPI anchoring the C-terminal end. Sequence comparison showed that guinea pig Thy-1 has an 82% homology to human and a 72% homology to mouse Thy-1 on the amino acid level. Immunohistological staining of cryostat sections revealed intensive staining with the monoclonal antibody H154 on fibroblasts, fibrocytes, Kupffer cells, alveolar macrophages, and mesangial cells. As observed in the human, mouse, and rat, Thy-1 is abundant in the guinea pig brain. Unlike Thy-1 expression in other species, guinea pig Thy-1 is strongly expressed on most resting, nonactivated B cells and, to a lesser extent, on erythrocytes. While treatment of erythrocytes and lymphocytes with GPI-specific phospholipase C largely decreased reactivity with mAb H154, T cells retained the proliferative response to antibody and phorbol esters.

L-arginine may mediate the therapeutic effects of low protein diets.

We have previously shown beneficial effects of dietary protein restriction on transforming growth factor beta (TGF-beta) expression and glomerular matrix accumulation in experimental glomerulonephritis. We hypothesized that these effects result from restriction of dietary L-arginine intake. Arginine is a precursor for three pathways, the products of which are involved in tissue injury and repair: nitric oxide, an effector molecule in inflammatory and immunological tissue injury; polyamines, which are required for DNA synthesis and cell growth; and proline, which is required for collagen production. Rats were fed six isocaloric diets differing in L-arginine and/or total protein content, starting immediately after induction of glomerulonephritis by injection of an antibody reactive to glomerular mesangial cells. Mesangial cell lysis and monocyte/macrophage infiltration did not differ with diet. However, restriction of dietary L-arginine intake, even when total protein intake was normal, resulted in decreased proteinuria, decreased expression of TGF-beta 1 mRNA and TGF-beta 1 protein, and decreased production and deposition of matrix components. L-Arginine, but not D-arginine, supplementation to low protein diets reversed these effects. These results implicate arginine as a key component in the beneficial effects of low protein diet.

Immunostimulation by Alsophila spinulosa extract fraction VII of both humoral and cellular immune responses.

Alsophila spinulosa (Cyatheaceae) has been used in Asia as a herbal medicine. In this study, the immunomodulatory effects of Alsophila spinulosa dried stems water extract fraction VII (AS-VII) were studied in vitro using an animal model. The results showed that AS-VII stimulated splenocyte proliferation in both BALB/c and C3H/HeJ mice. By cell fractionation analysis, the results showed that the mitogenic effect of AS-VII was predominantly on B cell population. The antibody response was also augmented by AS-VII in BALB/c and C3H/HeJ mice. The augmentation of immune responses in C3H/HeJ, the lipopolysaccharide (LPS)-hyporesponsive mouse strain, indicated that the activity was not simply due to the LPS contamination which may be present in AS-VII preparation. Furthermore, AS-VII caused an increase in cytotoxic T cell activity in a mixed lymphocyte reaction culture. These data indicate that AS-VII possesses the capability of augmenting both humoral and cellular immune responses.