Inter-alpha-trypsin inhibitor attenuates complement activation and complement-induced lung injury

Complement activation is a central component of inflammation and sepsis and can lead to significant tissue injury. Complement factors are serum proteins that work through a cascade of proteolytic reactions to amplify proinflammatory signals. Inter-alpha-trypsin inhibitor (IaI) is an abundant serum protease inhibitor that contains potential complement-binding domains, and has been shown to improve survival in animal sepsis models. We hypothesized that IaI can bind complement and inhibit complement activation, thus ameliorating complement-dependent inflammation. We evaluated this hypothesis with in vitro complement activation assays and in vivo in a murine model of complement-dependent lung injury. We found that IaI inhibited complement activation through the classical and alternative pathways, inhibited complement-dependent phagocytosis in vitro, and reduced complement-dependent lung injury in vivo. This novel function of IaI provides a mechanistic explanation for its observed salutary effects in sepsis and opens new possibilities for its use as a treatment agent in inflammatory diseases.

Peroxisome Proliferator–Activated Receptor α Protects against Glomerulonephritis Induced by Long-Term Exposure to the Plasticizer Di-(2-Ethylhexyl)Phthalate

Safety concerns about di-(2-ethylhexyl)phthalate (DEHP), a plasticizer and a probable endocrine disruptor, have attracted considerable public attention, but there are few studies about long-term exposure to DEHP. DEHP toxicity is thought to involve peroxisome proliferator-activated receptor alpha (PPARalpha), but this contention remains controversial. For investigation of the long-term toxicity of DEHP and determination of whether PPARalpha mediates toxicity, wild-type and PPARalpha-null mice were fed a diet that contained 0.05 or 0.01% DEHP for 22 mo. PPARalpha-null mice that were exposed to DEHP exhibited prominent immune complex glomerulonephritis, most likely related to elevated glomerular oxidative stress. Elevated NADPH oxidase, low antioxidant enzymes, and absence of the PPARalpha-dependent anti-inflammatory effects that normally antagonize the NFkappaB signaling pathway accompanied the glomerulonephritis in PPARalpha-null mice. The results reported here indicate that PPARalpha protects against the nephrotoxic effects of long-term exposure to DEHP.

Local IL-13 gene transfer prior to immune-complex arthritis inhibits chondrocyte death and matrix-metalloproteinase-mediated cartilage matrix degradation despite enhanced joint inflammation

During immune-complex-mediated arthritis (ICA), severe cartilage destruction is mediated by Fcgamma receptors (FcgammaRs) (mainly FcgammaRI), cytokines (e.g. IL-1), and enzymes (matrix metalloproteinases (MMPs)). IL-13, a T helper 2 (Th2) cytokine abundantly found in synovial fluid of patients with rheumatoid arthritis, has been shown to reduce joint inflammation and bone destruction during experimental arthritis. However, the effect on severe cartilage destruction has not been studied in detail. We have now investigated the role of IL-13 in chondrocyte death and MMP-mediated cartilage damage during ICA. IL-13 was locally overexpressed in knee joints after injection of an adenovirus encoding IL-13 (AxCAhIL-13), 1 day before the onset of arthritis; injection of AxCANI (an empty adenoviral construct) was used as a control. IL-13 significantly increased the amount of inflammatory cells in the synovial lining and the joint cavity, by 30% to 60% at day 3 after the onset of ICA. Despite the enhanced inflammatory response, chondrocyte death was diminished by two-thirds at days 3 and 7. The mRNA level of FcgammaRI, a receptor shown to be crucial in the induction of chondrocyte death, was significantly down-regulated in synovium. Furthermore, MMP-mediated cartilage damage, measured as neoepitope (VDIPEN) expression using immunolocalization, was halved. In contrast, mRNA levels of MMP-3, -9, -12, and -13 were significantly higher and IL-1 protein, which induces production of latent MMPs, was increased fivefold by IL-13. This study demonstrates that IL-13 overexpression during ICA diminished both chondrocyte death and MMP-mediated VDIPEN expression, even though joint inflammation was enhanced.

Involvement of dipeptidyl peptidase IV in immune complex-mediated glomerulonephritis

Dipeptidyl peptidase IV (DPPIV) is widely expressed in many tissues; however, its precise biological function is poorly understood. One of its possible physiologic roles is an involvement in the immune system, which plays a pivotal role in the pathogenesis of glomerulonephritis. The present study focused on the involvement of DPPIV in immune complex-mediated glomerulonephritis. Experimental nephritis was induced by anti-Thy-1.1 monoclonal antibody E30 using Wistar or F344 rats. The application of a new monoclonal antibody against DPPIV, F16, completely suppressed E30-induced proteinuria and mesangial proliferation in Wistar rats, whereas these preventive effects of F16 were not observed in F344 rats, which spontaneously lack DPPIV protein. Treatment with F16 inhibited glomerular deposition of complement C3 and complement C4 after the binding of E30 to the mesangial cell surface. Because the preventive effect of F16 was attributable to suppression of the complement cascade, we examined its influences on complement-dependent mesangial cell lysis in vitro. We discovered that the complement cascade was markedly inactivated in F16-treated Wistar rat serum but not in F16-treated F344 rats. These results indicate that DPPIV may play a somewhat crucial role in regulating the complement cascade and that inhibition of DPPIV may serve as a new target for preventing complement-dependent tissue injury.

[Beta-carotene prevention of immune disorders in workers engaged in the fire copper refining]

The paper deals with the studies of the human status and immunological responsiveness of workers engaged in copper-smelting industry. The examinees were found to more frequently develop lower environmentally induced immunological responsiveness followed by leuko- and lymphopenia, higher lymphocytic CD4+/CD8+ ratios, phagocytic dysfunction in peripheral blood. Preventive use of beta-carotene prevented negative changes in immunological parameters.

Anti-idiotype antibodies abrogate the tissue deposition of anti-RNP human autoantibodies injected into neonatal BALB/c mice

OBJECTIVE

The goals of the current work are: 1) to examine the epidermal deposition of anti-RNP IgG human autoantibodies in neonatal BALB/c mice; 2) to look for immunoregulatory effects of anti-idiotypes allowing one to inhibit the epidermal deposition of anti-RNP antibodies; and 3) to elicit antinuclear antibodies in adult BALB/c mice by internal images of anti-idiotypes.

MATERIALS AND METHODS

Anti-idiotype antibodies were produced with human anti-RNP IgG obtained by ion exchange chromatography; F(ab')2 fragments were recovered from pepsin digestion and were purified using Sephacryl S-300. F(ab')2 fragments were then used to immunize New Zealand rabbits.

RESULTS

The anti-RNP IgG recognized the 70 kDa protein and the A (31 kDa) and C (19 kDa) proteins, while the anti-idiotype antibody specifically recognized the light or heavy chain of the anti-RNP (Fab')2 fragments. Additionally, anti-idiotypes recognized the anti-RNP IgG from some sera, but not the IgG from other specificities or from normal IgG. When anti-RNP IgG was injected intraperitoneally into BALB/c mice it induced immune complex deposition in the epidermis and at the dermal-epidermal junction. Previous injection of anti-idiotype antibodies abrogated the anti-RNP IgG deposits. Vaccination with anti-idiotypes elicit antinuclear antibodies in adult BALB/c mice.

CONCLUSIONS

Anti-idiotype antibodies abrogate in vitro the antinuclear antibody deposition in neonatal BALB/c mice. Anti-idiotype antibodies elicit antinuclear antibodies in adult BALB/c mice.

Uptake of apoptotic leukocytes by synovial lining macrophages inhibits immune complex-mediated arthritis

Previously we have shown that synovial lining macrophages (SLMs) determine the onset of experimental immune complex-mediated arthritis (ICA). During joint inflammation, many leukocytes undergo apoptosis, and removal of leukocytes by SLMs may regulate resolution of inflammation. In this study we investigated binding and uptake of apoptotic leukocytes by SLMs and its impact on the onset of murine experimental arthritis. We used an in vitro model to evaluate phagocytosis of apoptotic cells on chemotaxis. Phagocytosis of apoptotic thymocytes resulted in a significant decrease (58%) of chemotactic activity for polymorphonuclear neutrophils (PMNs). If apoptotic cells were injected directly into a normal murine knee joint, SLMs resulted in a prominent uptake of cells. After ICA induction, electron micrographs showed that apoptotic leukocytes were evidently present in SLMs on days 1 and 2. Injection of apoptotic leukocytes into the knee joint 1 h before induction of ICA significantly inhibited PMN infiltration into the knee joint at 24 h (61% decrease). This study indicates that uptake of apoptotic leukocytes by SLM reduces chemotactic activity and inhibits the onset of experimental arthritis. These findings indicate an important mechanism in the resolution of joint inflammation.

Intravenous immunoglobulin protects against experimental thrombotic microangiopathy

BACKGROUND

Intravenous immunoglobulin (IVIG) has been utilized in several forms of vasculitis and has many potential mechanisms of action, including the inhibition of C3 activation. We have previously demonstrated that IVIG can reduce glomerular injury in a model of membranous nephropathy mediated by C5b-9 [1]. C5b-9 has also been shown to mediate the thrombotic microangiopathy (TMA) induced by antibody to glomerular endothelial cells leading to a hemolytic uremic syndrome-type lesion [2].

METHODS

To test the hypothesis that IVIG might be effective in treating antibody-induced TMA, male uninephrectomized rats underwent right renal artery perfusion with goat anti-rat glomerular endothelial cell (GEN) antibody (20 mg/kg). Sheep IgG (200 mg/kg) was administered either 30 minutes before the renal artery perfusion (group I, N = 6) or 30 minutes postperfusion (group II, N = 9). A third control group received phosphate-buffered saline (PBS; group III, N = 12). A survival biopsy was performed at 15 minutes, and the animals were sacrificed on day 2.

RESULTS

There were no significant differences in proteinuria or hematocrit between the groups. Animals pretreated with IVIG had significantly improved survival and renal function, which was associated with a decrease in glomerular C3 deposition. The protective effect of IVIG was abolished if the administration was delayed 30 minutes after perfusion.

CONCLUSIONS

IVIG is effective in reducing injury in experimental TMA only if given prophylactically. The effect is mediated by inhibition of local intraglomerular complement activation.

Novel therapies in the treatment of systemic lupus erythematosus

This review highlights the advances made in the use of biological and immunomodulatory agents in systemic lupus erythematosus. Although there have been disappointments (eg, anti-CD40 ligand, DNAse), it is clear that DHEA and mycophenolate mofetil will have a place in the management of the disease. In our opinion, leflunomide and LJP-394 are the most promising therapies currently, under study.

Administration of IgG Fc fragments prevents glomerular injury in experimental immune complex nephritis

Most human nephritis is due to glomerular deposition and/or formation of immune complexes (IC). In cultured mesangial cells, Fc receptor stimulation induces proliferation, matrix synthesis, and release of several mediators implicated in the initiation and progression of glomerular injury. Since Ig Fc fragments in vitro modified these phenomena, we studied the effects of systemic administration of IgG Fc fragments on the evolution of experimental IC nephritis. Fc fragment injection (1 mg/day i.p.) to rats with ongoing nephritis (proteinuria 20-50 mg/24 h vs 9 +/- 0.2 mg/24 h in controls) markedly ameliorates proteinuria, renal function, and morphological renal lesions. This was accompanied by a reduction in the renal synthesis of chemokines (monocyte chemoattractant protein-1, IFN-inducible protein-10, and cytokine-induced neutrophil chemoattractant-1), matrix proteins, and growth factors (platelet-derived growth factor, and TGF-beta), and in the activity of transcription factors. The treatment did not affect the glomerular deposition of IgG IC and complement C1q. In contrast, a decrease in the renal expression and production of C3 was observed without changes in serum complement levels. In vitro, very low complement consumption and no C3b covalent interaction were observed with Fc fragments, confirming that they did not modify systemic complement activity. These results indicate that the administration of Fc fragments prevents the development of glomerular damage in an aggressive model of proliferative glomerulonephritis through mechanisms involving a reduced local generation of complement, chemokines and growth factors. Modulation of IC-mesangial cell interaction by Fc fragment administration could represent a new approach to the treatment of severe immune nephritis.

[Management and choice of antibiotics for patients with an allergy to penicillin]

Allergic reactions to penicillin occur in 0.7-8% of treatments. Management of bacterial infections in patients allergic to penicillin depends on the availability of alternative antibiotics and on the type of allergy. Skin tests can be used to exclude the risk of IgE-mediated reactions (e.g. anaphylaxis) to subsequent penicillin administration. If penicillin is the first choice for treatment and the patient has an IgE-mediated allergy (on the basis of a positive skin test), desensitization therapy to the drug can be performed.

A role for P-selectin in neutrophil and platelet infiltration in immune complex glomerulonephritis

P-selectin is one of the key early mediators of leukocyte adhesion in inflammatory conditions. This report examines the role of P-selectin in a neutrophil- and platelet-mediated model of glomerulonephritis (the concanavalin A [con A] model). The administration of neutralizing anti-P-selectin antibody (PB 1.3) reduced the platelet influx at 10 min (P < 0.05) and was associated with a 60% reduction in the neutrophil infiltrate and a 50% reduction in the number of oxidant-producing cells at 3 h within glomeruli. No effect on glomerular monocyte-macrophage accumulation was observed, and proteinuria was reduced by 20% but did not reach significance. It is concluded that P-selectin plays an important role in mediating the neutrophil and platelet accumulation in this model and likely has a role in mediating the glomerular injury.

The diseases of Alzheimer and Pick from the viewpoint of prevention

Alzheimer disease, Pick disease and senile dementia are all characterized by similar morphological changes, both macroscopic and microscopic, and similar psychiatric symptoms. All three should, therefore, be viewed as aspects of one disease, which is termed Alzheimer-type dementia. Nothing contradicts the view that immune complexes take part in the etiology of Alzheimer-type dementia. There are various types of immune complexes and so their points of action in the organism may vary. There might be two main means of preventing Alzheimer-type dementia: the first could be named the serological (basic) and the second relying on pharmacotherapy (additional). Pharmacological prevention of disease might be aided by the use of parasympathomimetic drugs, e.g. pilocarpine.

Attenuation of immune complex nephritis in NZB/WF1 mice by a prostacyclin analogue

Although prostaglandins have been shown to inhibit the evolution of the nephritis in NZB/W mice, the mechanisms of this effect are unknown. To characterize such inhibition, we injected the prostacyclin (PGI2) analogue, beraprost, into NZB/W mice, using 0.5 mg, 1.0 mg or 5.0 mg beraprost/kg body weight of test animals three times in 1 week when the mice were 2 months old. Evaluation included measurement of urine albumin excretion, serological parameters and splenic T cell subset, as well as examination of renal histology by light and fluorescence microscopy. Mice given beraprost showed a marked decrease in urine albumin excretion and in glomerular hypercellularity compared with untreated controls. Maximal beneficial effects occurred when the dose was 5.0 mg/kg of beraprost. These effects correlated with a reduction of immune complex deposition in glomeruli. In addition, beraprost reduced serum levels of immunoglobulins and anti-double-stranded DNA antibodies, and decreased the number of helper (L3T4+) T cells in splenocytes. These results indicate that beraprost attenuates the nephritis of NZB/W mice, and that the source of this effect is the reduced production of autoantibodies and deposition of immune complexes in glomeruli.

Protective effects of sialylated oligosaccharides in immune complex-induced acute lung injury

Using sialyl Lewisx (SLX) oligosaccharides derived from fucosyl transferase-expressing cells or generated synthetically, the ability of these compounds to protect against acute lung damage after deposition of immunoglobulin (Ig)G or IgA immune complexes has been determined. The synthetic compounds were tetra- and pentasaccharide derivates of SLX as well as the nonfucosylated forms of SLX as controls. In the IgG immune complex model of lung injury, which is E-selectin dependent, SLX preparations provided dose-dependent protective effects, as assessed by changes in lung vascular permeability and hemorrhage. Protective effects were associated with diminished tissue accumulation of neutrophils in lungs (as assessed by myeloperoxidase). Morphological assessment revealed reduced physical contact of neutrophils with the pulmonary vascular endothelium and reduced tissue accumulation of neutrophils. In the model of IgA immune complex-induced lung injury, which does not involve participation of neutrophils and is independent of the requirement for E-selectin, SLX preparations were not protective. These data suggest that, in neutrophil-mediated and E-selectin-dependent lung injury, SLX preparations provide significant, protective effects against inflammatory vascular injury. The ability to achieve antiinflammatory outcomes in vivo with appropriate oligosaccharides suggests a new approach to the blocking of acute inflammatory responses.

Protective effects of inhibitors of nitric oxide synthase in immune complex-induced vasculitis

1. The ability of analogues of L-arginine (N-iminoethyl-L-ornithine (L-NIO), NG-monomethyl-L-arginine (L-NMMA), NG-nitro-L-arginine methyl ester (L-NAME) and NG-nitro-L-arginine (L-NNA)) to protect against inflammatory injury induced by activated neutrophils was investigated in rats following intradermal or intrapulmonary deposition of immune complexes. 2. The descending order of potency for protective effects of these analogues was: L-NIO > L-NMMA > L-NNA = L-NAME. The approximate IC50 value for L-NIO in the dermal vasculitis model was 65 microM. For all other compounds, the IC50 values were > 5 mM. 3. The protective effect of L-NIO in the skin was reversed in a dose-dependent manner by the presence of L-arginine, but not by D-arginine. L-Arginine also reversed the protective effects of L-NIO in immune complex-induced lung injury. 4. The protective effects of L-NIO were not associated with reductions in neutrophil accumulation, as measured by extraction from tissues of myeloperoxidase. 5. These data demonstrate that L-NIO has the most potent protective effects against immune complex-induced vascular injury induced by activated macrophages. Furthermore, they indicate that this injury is dependent upon the generation of nitric oxide.

An in vivo model for the experimental selection of drugs able to prevent immune complex glomerulonephritis

Polyclonal activation of lymphocytes and immune complex-mediated glomerular lesions were induced in C57Bl/6 mice by injecting bacterial lipopolysaccharide (LPS) twice a week for 2 weeks. The usefulness of such a model for in vivo evaluation of immunomodulatory and therapeutic effects of drugs, was investigated by treating mice with DIAM4, a cyclophosphazenic compound known to modulate polyclonal activation of lymphocytes and to prevent mouse lupus nephritis. Prevention of LPS-triggered lymphocyte polyclonal activation and glomerular lesions was observed in the DIAM4-treated mice. Such a model can be used conveniently to select compounds effective in the treatment of immune glomerulonephritis.

Effect of cyclosporin on immune complex deposition in murine glomerulonephritis

Chronic glomerulonephritis (GN) was induced in N/M mice by daily injections of human serum albumin (HSA). The glomerular lesion was similar to that observed in human membranous GN and was characterized by intense mesangial and capillary loop immunofluorescent staining for HSA, IgG and C3. Electron microscopic examination revealed numerous electron-dense deposits in the mesangium and along the subepithelial side of the glomerular basement membrane, the latter deposits being associated with membranous spikes. Chronically injected mice that had been treated with cyclosporin (CsA) from Day 1 had different patterns of immune complex deposition. Mesangial deposition was apparently unaltered but no subepithelial deposits or spikes were evident. In addition, only two out of 21 HSA-injected mice which began CsA treatment on Day 21 had subepithelial deposits. There was no significant difference in serum levels of HSA-specific IgG between the three groups of mice. CsA treatment would therefore appear to ameliorate the immunopathology of antigen-induced glomerulonephritis in this model without affecting serum antibody levels, and may be of therapeutic value in the treatment of human membranous GN.

[Effects of YM-13650 on experimental nephritis in rats and mice]

We investigated the effects of YM-13650, 2-(m-carboxyacetoxyphenyl) imidazo [2, 1-b] benzothiazole, on BSA-immune complex nephritis in rats and lupus nephritis in NZB/W F1 mice. In preventative experiments on immune complex nephritis in rats, YM-13650 (10 approximately 100 mg/kg, p.o.) dose-dependently inhibited the increase in urinary protein, serum cholesterol, and urea nitrogen. Histopathological observation showed striking hypercellularity and mesangial widening in nephritic control; however, glomerular injury was reduced in YM-13650-treated animals. In therapeutic study, control rats maintained high levels of urinary protein, serum cholesterol and urea nitrogen throughout the experimental period. These variables were lower in YM-13650-treated rats. In preventative experiments in lupus mice treated from 8 weeks of age, YM-13650 in comparison with the control group showed a lesser degree of proteinuria throughout the experimental period. It also significantly prolonged or tended to prolong the life span of NZB/W F1 mice compared with the control. In therapeutic experiments conducted after the onset of lupus nephritis in mice, the drug also inhibited an increase in urinary protein and tended to prolong the life span. These results show that YM-13650 has preventative and therapeutic effects on experimental nephritis in rats and mice, and it may prove valuable as an anti-nephritic drug.

Murine mercury-induced immune-complex disease: effect of cyclophosphamide treatment and importance of T-cells

The renal immune-complex (IC) disease induced in BALB/c mice by subcutaneous injection of mercuric chloride (1.6 mg/kg b.w.) every third day for 8 weeks was prevented by the intraperitoneal injection of cyclophosphamide (20 mg/kg b.w.) 24 h prior to mercury injection. The importance of T-cells in the induction of immune-complex disease was studied. BALB/c mice given drinking water containing 20 mg/l of HgCl2 for 10 weeks showed an increased titre of granular, mesangial IgG deposits and vessel wall IgG deposits. Identically treated, congenic nude BALB/c mice with a similar body burden of mercury developed no IC-disease. Cytophotometric analysis of the T-cell subsets in subcutaneously mercury-treated mice revealed a decrease in the fraction of T-helper (L3T4+) splenic cells in the SJL and C57BL/6J strains; no significant change in the T-cell subsets was found in BALB/c mice. C57BL/6J mice, resistant to induction of IC-disease by mercury, showed no increase in the fraction of T-suppressor/cytotoxic (Lyt-2+) cells and no change in the T-helper/T-suppressor cell ratio. C57BL/6J mice could not be rendered susceptible to mercury-induced IC-disease by treatment with different doses of cyclophosphamide.

Effect of several kinds of drugs on the development of autoimmunity in MRL/Mp-lpr/lpr mice; lack of correlation between the suppression of autoantibody production and prevention of autoimmune disease

MRL/Mp-lpr/lpr (MRL/l) mice spontaneously develop autoimmune kidney disease which resembles human systemic lupus erythematosus (SLE). Employing this strain of mouse, we examined the effect of several immunosuppressants and a newly synthetized anti-nephritic agent, 4-chloro-3',6'-dimethyl-2,2'-iminodibenzoic acid (TO-115) on both the development of immunological abnormalities and the clinical symptoms of autoimmune kidney disease. This study aimed to determine how much the magnitude of autoantibody suppression related to the degree of prevention of autoimmune nephritis. Immunological abnormalities were assessed by measuring the serum levels of anti-deoxyribonucleic acid and anti-trinitrophenyl antibodies, rheumatoid factor (RF), and immune complex (IC). The status of autoimmune kidney disease was monitored by means of the appearance of proteinuria and survival time and the measurement of serum levels of blood urea nitrogen (BUN) and cholesterol. Immunosuppressants such as cyclophosphamide (CY), 6-mercaptopurine (6 MP) and sodium aurothiomalate (SAT) remarkably suppressed the development of immunological abnormalities in a dose dependent manner. Interestingly, however, only CY showed the suppressive effect on the development of autoimmune kidney disease with prolongation of survival time and the excretion of proteinuria. In contrast, 6-MP and SAT did not inhibit the development of autoimmune kidney disease. On the other hand, TO-115 did not suppress the development of immunological abnormalities, but it restrained the symptoms of autoimmune kidney disease. Taken together, the suppression of autoantibody production does not always lead to prevention of the development of autoimmune kidney disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Protective effect of polyunsaturated fatty acid supplementation in apoferritin induced murine glomerulonephritis

The effects of increasing two dietary polyunsaturated fatty acids, eicosapentaenoic and linoleic, on the glomerulonephritis induced by repeated injections of apoferritin in the mouse were studied. Urinary protein excretion was measured serially; serum creatinine, aortic and renal production of eicosanoids and kidney histology were measured at sacrifice at 8 weeks. Both high EPA and LA feedings were associated with lesser proteinuria, normalization of renal function and profound changes in the tissue production of prostaglandin and thromboxane, which may explain their protective effect in this model of renal disease.

Effects of dietary linoleic acid enrichment on induction of immune complex nephritis in mice

In pharmacologic doses E series prostaglandins attenuate the development of immune complex nephritis. We studied the effect of the dietary prostaglandin precursor linoleic acid on murine apoferritin-induced immune complex glomerulonephritis. High, normal, or low linoleic acid diets were fed to mice for 4 weeks prior to and during the intraperitoneal apoferritin administration. A high linoleic acid diet feeding was associated with less proteinuria, less renal histologic damage, and prevented a rise in serum creatinine. We conclude that linoleic acid has a protective effect on the development of murine apoferritin-induced immune complex nephritis.

Antigen-specific suppression of the experimental immune complex glomerulonephritis in rabbits by means of highly hot labelled antigen

We succeeded in suppressing almost completely the development of glomerular immune disease in a new experimental model, i.e. in the model of immune complex glomerulonephritis. Previous injection of highly hot labelled BSA was able to prevent very significantly the appearance of kidney injury. This result must be interpreted as the consequence of suppression of the synthesis of anti-BSA-antibody by means of previously applied highly hot labelled BSA. As a consequence of the lack of anti-BSA-antibodies there is no formation of antigen-antibody complexes, no deposition of these complexes in the glomerulus basement membrane, and no development of glomerular immune complex disease. Radioactivity alone (125I coupled to HGH) was not capable of modifying or suppressing the synthesis of antibody and consequently, the formation of antigen-antibody complexes.

Antigen feeding modifies the course of antigen-induced immune complex disease

Low affinity mice, prone to chronic immune complex disease (ICD) induced by daily injection of antigen, were fed 0.05% HSA in their drinking water for 7 days before the start of daily injections of HSA. Antigen feeding resulted in a marked decrease in the incidence of ICD despite the presence of high levels of circulating immune complexes. These complexes, which persisted in the circulation for long periods, were of low molecular weight and did not localize in the glomeruli. Antigen fed mice had lower levels of free antibody in their sera compared with control mice which may have favoured the formation of small latticed complexes in antigen excess. Antibody affinity was not apparently affected by prior feeding with antigen.

Immunotherapy of murine leukemia. V. Protection against Friend leukemia virus-induced immune complex glomerulonephritis by passive serum therapy

The development of immune complex glomerulonephritis in DBA/2 mice infected with Friend murine leukemia virus (F-MuLV) was compared with that in mice protected against virus-induced disease by administration of chimpanzee anti-F-MuLV antiserum (CaF-MuLV). Morphologic analysis of glomeruli from viremic (infected) normal chimpanzee serum-treated animals revealed significant renal disease within 2 weeks following virus inoculation, with glomerular immune complex deposits and C-type viral particles seen by electron microscopy. Localization of F-MuLV envelope and core antigens (gp71 and p30, respectively) was also detected by immunofluorescence, as was murine IgG and C3. However, age-matched DBA/2 mice treated with CaF-MuLV antiserum alone or following F-MuLV inoculation showed no evidence of systemic disease and neither localization of F-MuLV antigens nor detectable virus particles. These data indicate that in addition to erythroleukemia, F-MuLV infection results in severe immune complex glomerulonephritis and that passive immunotherapy can protect susceptible mice from both aspects of viral pathogenesis.

Prevention of glomerulonephritis and prolonged survival in New Zealand Black/New Zealand White F1 hybrid mice fed an essential fatty acid-deficient diet

Female B/W mice spontaneously develop an autoimmune disease that is similar to systemic lupus erythematosus. Antibodies to doublestranded DNA (dsDNA) and antinuclear antibodies develop in aging animals; death from immune complex-mediated glomerulonephritis occurs from 8 to 12 mo of age. It has been reported that prostaglandin (PG)E(1) treatment of such mice prolongs survival. In the present study, four groups of female B/W mice were studied beginning at 6-11 wk of age on the following regimens: (a) a synthetic diet that contained 20% safflower oil, (b) a standard laboratory chow diet, (c) a standard diet together with injections of PGE(1), and (d) an essential fatty acid-deficient synthetic diet that contained 20% coconut oil. All animals were tested monthly for antinuclear antibodies and anti-dsDNA. Kidney tissue was obtained for light and immunofluorescence microscopy when animals were dying. All disease manifestations were altered strikingly in the essential fatty acid (EFA)-deficient animals. Intermediate benefit was seen in PGE(1)-treated animals. 7% of the control animals and 18% of safflower oil-fed animals survived to 10 mo. In contrast, the PGE(1)-treated and EFA-deficient mice had a similar survival rate (78-88%). At age 16 mo, 78% of EFA-deficient mice and 45% of PGE(1)-treated mice were alive. 25% of the PGE(1)-treated and 55% of the EFA-deficient animals survived to 20 mo. Serum anti-dsDNA appeared at age 5 mo in safflower oil-fed and control animals, but not until 9 and 12 mo for PGE(1)-treated and EFA-deficient animals, respectively. All kidneys from 7- to 9-mo-old safflower oil-fed and control animals and the majority of kidneys from PGE(1)-treated animals were abnormal by light and immunofluorescence microscopy. Kidneys from EFA-deficient animals were essentially normal at 10 mo. At 13 mo, all PGE(1)-treated animals examined had significant kidney involvement, whereas none of the EFA-deficient animals had glomerulonephritis. These findings demonstrate that an EFA-deficient diet has a beneficial effect on murine lupus erythematosus.

Thiamphenicol and lupus nephritis. II. The effects of giving the drug from weaning to NZBxOUW F1 hybrid female mice

Thiamphenicol at the rate of 50 mg/kg/day given to female NZBxOUW F1 hybrid mice from weaning and continuing throughout life resulted in a considerable extension of lifespan, although this was less than in mice given the same drug dosage from first antinuclear antibody (ANA) positivity (Simpson, Aarons and Howie, 1979). Assessment of the changes in renal dysfunction and renal histology shows that thiamphenicol treatment did not prevent the development of immune complex glomerulonephritis although the rate of progression of the disease was slower than in untreated controls. Thiamphenicol failed to influence greatly the progressive anaemia which develops in these mice or to alter the pattern of ANA production. Although azotaemia developed in treated mice it was a terminal event. It was concluded that the action of thiamphenicol was to depress but not prevent immune complex formation possibly by impairing immunoglobulin formation although why immunofluorescent ANA formation remained unaffected is not understood.

Prostaglandin E1 treatment of NZB/NZW F1 hybrid mice. II. Prevention of glomerulonephritis

The F1 hybrid of New Zealand black and New Zealand white mice--the NZB/NZW mouse--spontaneously develops a disease similar to human systemic lupus erythematous, characterized by impaired cell-mediated and enhanced humoral immune responses, development of antibodies to nuclear antigens, and immune complex glomerulonephritis. Because there is experimental evidence that prostaglandin E1 (PGE1) can enhance T-cell function and cell-mediated responses and suppress B-cell activity, NZB/NZW mice were treated with 200 microgram PGE1 subcutaneously once or twice daily from 6 weeks of age. PGE1 treatment of female and male mice prevents giomerular deposition of immunoglobulins and complement (monitored by immunofluorescence), and development of the proliferative glomerulonephritis (determined by light and electron microscopy) characteristic of untreated NZB/NZW mice. After 1 year of treatment, 18 of 19 female mice survived, whereas only 2 of 19 untreated control mice were alive. Male mice treated with 200 microgram PGE1 daily were also protected: 9 of 11 versus 2 of 9 untreated mice were alive at 65 weeks. PGE1 treatment did not prevent development of antibodies to nuclear material in any of the treated groups.

Rational management of uveitis

Endogenous uveitis is an important cause of blindness in young adults. The need for a comprehensive search for an aetiological 'antigen' is stressed. A source of adjuvant, disturbance in host immunology and any associated syndromes are also sought. Treatment then involves elimination of 'antigen', suppression of host hypersensitivity and the enhanced vascular permeability, and improvement of host resistance. The value of antihistamine and antiserotonin drugs in successful treatment is emphasised.

Therapeutic studies in NZB/W mice. IV. Effect of combination drug therapy on immune complex deposition

Azathioprine, cyclophosphamide, and methylprednisolone given individually to NZB/NZW mice retard the development of autoimmune nephritis and prolong survival in these mice. Administration of the combination of all three drugs is superior to one or two drug regimens. In the present study the kidneys of mice treated with all single, double, and triple drug regimens were compared for the degree of deposition of immunoglobulin and complement. The triple drug regimen significantly reduced overall deposition of immunoglobulin and complement compared with any other regimen. Complement and gamma2 were significantly reduced by triple drug therapy compared with any other regimen. The triple drug regimen reduced gamma1 compared with untreated and double drug treated mice. The single, double, and triple drug regimens significantly reduced gammaM deposition to about the same degree. Deposition of gammaA was not significantly reduced by any regimen. Circulating levels of these immunoglobulin classes were not reduced, a fact suggesting that the reduction in autoimmune nephritis resulting from triple drug therapy is associated with superior reduction in immune complex deposition rather than with generalized, non-specific immunodepression.

Cyclophosphamide protection in NZB/NZW disease. Mechanisms and therapeutic regimens

Regular administration of cyclophosphamide to NZB/NZW female mice effectively protects against the nephritis that is thought to be a model for human SLE nephritis. Reductions in serologic, histologic, and immunogluorescent parameters of the disease are correlated. Intermittent as well as continuous administration of the drug is effective without the development of leukopenia. Possible mechanisms of drug action and a modified approach to therapy of immune complex disease are discussed.