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Isolation of enteric glia and establishment of transformed enteroglial cell lines from the myenteric plexus of adult rat.

Although enteroglial cells (EGCs) may play a key role in the inflammatory response of the enteric nervous system, little is known about their immunophysiological properties. To facilitate further characterization of enteric glia, we have developed a novel method to isolate and purify EGCs from the myenteric plexus. Myenteric plexus preparations were enzymatically dissociated and EGCs purified by complement-mediated cytolysis of contaminating cells and transformed by retroviral gene transfer. Primary and transformed cells were characterized immunohistochemically and by dot-blot analysis. Functionally, c-fos mRNA expression was assessed in primary and transformed enteroglial cells. All cells displayed robust glial fibrillary acidic protein, S-100 and vimentin immunoreactivities, but no Thy-1.1, desmin, smooth muscle alpha-actin or C3 complement receptor immunoreactivity. This confirmed their enteroglial lineage and excluded contamination with other cell types. Both primary and transformed EGCs displayed little constitutive c-fos mRNA expression. This, however, could be upregulated by various stimuli, including proinflammatory cytokines. In summary, we present a novel method to purify EGCs from rat myenteric plexus for tissue culture and to establish transformed EGC lines that retain their glial nature and functional properties. Such cell lines are now available for physiological studies of the functional properties of enteric glia in vitro.

Animals↗

Triggering of respiratory burst by phagocytosis in monocytes of patients with systemic lupus erythematosus.

The triggering of the respiratory burst by phagocytosis via different receptors in monocytes of patients with systemic lupus erythematosus (SLE) was investigated. The superoxide anion synthesis was assayed by reduction of ferricytochrome C that was inhibited by superoxide dismutase. The mononuclear cell suspensions were triggered by IgG-coated latex, C3 complement fragment-coated and uncoated yeast (Saccharomyces cerevisiae). Superoxide generation induced by phagocytosis via Fc gamma R was decreased in monocytes of patients with SLE. On the other hand, MoAbs against Fc gamma RI, Fc gamma RII and especially CR3 could also induce superoxide anion synthesis. At the same time, superoxide generation induced by anti-CR3 could be inhibited with C3-coated yeast.

Antibodies, Monoclonal↗

Protein clearances and selectivity determinations in childhood nephrosis: a reappraisal.

To critically evaluate the clinical utility of determining specific proteins in patients with extensive proteinuria, we used immunonephelometric methods to measure albumin, transferrin, IgG, and alpha 2-macroglobulin in serum and in 24-h urine specimens from 37 children with idiopathic nephrotic syndrome. Renal biopsy demonstrated minimal change disease (I) in 15, focal glomerulosclerosis (II) in 15, and membranoproliferative glomerulonephritis (III) in seven patients. A three-group nonparametric rank test and three-group discriminant function analysis of the protein excretion and clearances of the four proteins we measured revealed significant differences in the excretion of IgG and the clearance of alpha 2-macroglobulin among the three groups of patients (p less than 0.05). Only patients with III had low serum complement C3 concentrations. Patients with I or II were best discriminated by differences in the excretion of transferrin and IgG, the clearance of alpha 2-macroglobulin, and the selectivity index (the clearance ratio of IgG/transferrin). These data indicate that measurement of specific urinary proteins and selectivity determinations may be helpful in predicting the type of histopathology and the prognosis of nephrotic children who have normal complement concentrations.

Adolescent↗

A case of atypical hemolytic uremic syndrome with a transient decrease in complement factor H.

We report a case of sporadic atypical hemolytic uremic syndrome (HUS) with a transient decrease in complement factor H. Referred for hemolysis and azotemia without diarrhea prodrome, this 31-month-old boy showed a decreased complement 3 (C3) and complement factor H (FH) level. However, the factor H gene (HF1) mutation was missing. After the hemolysis was controlled with plasma infusion, the C3 and FH levels recovered. The patient's renal function fully recovered and remained normal, and there was no recurrence of the HUS.

Child, Preschool↗

Effects of cyclosporine A on serum and urinary soluble interleukin-2 receptor in patients with lupus nephritis.

OBJECTIVE: To evaluate the association of the level of urine and serum soluble interleukin-2 receptor (sIL-2R) with disease activity and response to cyclosporine A (CsA) therapy in patients with lupus nephritis (LN). METHODS: Sixteen hospitalized patients with LN were studied. At admission, fifteen patients had type IV-LN and one had type V-LN. All patients received CsA 6 mg/kg per day for 6-8 weeks, then tapered off gradually to 2 mg/kg per day. The levels of urinary and serum sIL-2R were determined by enzyme-linked immunosorbent assay (ELISA). Serum antinuclear antibody (ANA), anti-dsDNA antibody (A-ds-DNA), complement C3 and C4, total IgG, creatinine, urinary red blood cells and protein excretion, and lymphocyte subpopulations in the peripheral blood were also measured before and after CsA treatment. RESULTS: In LN patients, both urinary (534 +/- 101 U/ml) and serum SIL-2R levels (326 +/- 148 U/ml) were higher than those in normal controls. These findings were associated with higher levels of peripheral blood CD4 + and CD8 + lymphocytes (29.3 +/- 4.24 and 28.6 +/- 9.12%), higher titer of serum anti-ds-DNA, lower levels of serum complement C2 and C4 (0.98 +/- 0.23 and 0.24 +/- 0.12 g/L), as well as more proteinuria (Upro 2.99 +/- 0.76 g/24 hrs) and hematuria (URBC 83.9 +/- 95.2 10(4)/ml). These abnormalities were gradually ameliorated by CSA therapy. The changes in the levels of both serum (116 +/- 58.6 U/ml) and urine (136 +/- 43.2 U/ml) SIL-2R induced by CsA (at 8 weeks) were correlated with the changes in the levels of CD4 + and CD8 + cells (23.2 +/- 3.30 and 26.7 +/- 3.54%), degrees of immune abnormalities (serum C3 and C4 1.28 +/- 0.14 and 0.42 +/- 0.06 g/L), and renal injuries (Upro 1.07 +/- 0.46 g/24 hrs, URBC 5.82 +/- 3.15 10(4)/ml). CONCLUSIONS: These results suggest that serum and urinary sIL-2R are sensitive markers for the disease activity in patients with LN. CsA, a powerful immunosuppressive agent, significantly improves both immunologic disorders and renal functional impairments, the mechanism of which on patients with LN appears to inhibit the lymphocyte activation in the peripheral blood and renal tissues as indicated by the decrease in sIL-2R levels.

Adolescent↗

Reticuloendothelial system Fc receptor-mediated clearance of IgG-tagged erythrocytes from the circulation of patients with idiopathic ulcerative colitis and chronic liver disease.

Immune complexes may be important in the pathogenesis of the liver disease associated with idiopathic ulcerative colitis. In the present study, we documented Fc receptor-mediated clearance by the reticuloendothelial system of immune complex-like material from the systemic circulation of 25 healthy control subjects, 19 patients with ulcerative colitis alone, 9 patients with ulcerative colitis and elevated liver enzyme tests and 8 patients with various other forms of chronic liver disease. Following an intravenous infusion of IgG-tagged 51Cr-labeled autologous erythrocytes, serial blood samples were drawn over a 2-hr period of time, and computer-generated clearance curves were obtained. The time required for clearance of 50% of infused erythrocytes (T1/2) was then calculated. Serum immunoglobulin (IgA, IgG and IgM), complement (C3 and C4) and immune complex-like activity (IgG and IgM types) were also determined. Sixteen of 19 (84%) ulcerative colitis patients and 7 of 8 (88%) chronic liver disease patients had normal clearance T1/2's (when compared to 25 healthy controls). Conversely, only 1 of 9 (11%) ulcerative colitis + chronic liver disease patients demonstrated normal clearance function. Aside from serum IgM levels, the results of serum immunoglobulin, complement and immune complex-like determinations were similar in ulcerative colitis and ulcerative colitis + chronic liver disease patients. Serum IgM levels, however, were significantly decreased in ulcerative colitis patients and increased in ulcerative colitis + chronic liver disease patients (p less than 0.001). The results indicate that the reticuloendothelial system of patients with ulcerative colitis and chronic liver disease is impaired in its ability to dear immune complex-like material from the systemic circulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

An immunoperoxidase study of immunological factors in high immune and low resistance granulomas in leprosy.

The epithelioid cell granuloma in high resistant tuberculoid (TT) leprosy was contrasted with the pure macrophage granuloma of anergic lepromatous leprosy (LL) by evaluating various immunological factors operating in these lesions. The immunoperoxidase technique using antisera to immunoglobulin IgG, IgM, complement C3, C3d and C1q and other products of macrophage secretion, lysozyme, plasminogen, a1 antitrypsin and C-reactive protein and of Ia antigens revealed peak levels in tissues of most of these factors in both types of granuloma. The tuberculoid response was linked to low antigenic load and Ia-like antigen and the lepromatous response was secondary to a high antigenic load in the absence of Ia antigen. Complement and other mediators were found intracellularly in both tuberculoid and lepromatous granulomas, but extracellularly only in tuberculoid lesions. This may indicate local hypersensitivity in the tuberculoid granuloma. It is suggested that the mediators in LL macrophages remain bound to lipids of mycobacterial degenerations in the phagocytic vacuole. Secretory cells were differently sited in the two types of granulomas: peripheral in epithelioid cell lesions and central around capillaries over the whole lesion in pure macrophage granulomas of LL. In tuberculoid leprosy many of the central vessels in the granuloma were obliterated. C1q was found in fibroblasts. However, the marked absence of fibrosis in any of the lesions of leprosy, except following severe reactions, casts some doubt on the link which has been postulated between epithelioid cells and fibroblasts as an explanation of fibrosis in granulomas.

Complement System Proteins↗

Protection of germinal centres from complement attack: decay-accelerating factor (DAF) is a constitutive protein on follicular dendritic cells. A study in reactive and neoplastic follicles.

The development of B-cell memory is linked to the presence of germinal centres. This process is dependent on the presence of antigen, usually in the form of immune complexes with antibody, on the surface of the follicular dendritic cells (FDCs) that form a network in the germinal centre. The presence of immune complexes poses a constant danger of activating complement. Decay accelerating factor (DAF, CD55) and the membrane attack complex (MAC) inhibitor (CD59) are two cell proteins whose sole function is to protect cells from the action of complement, the former affecting the earlier components of the complement cascade, and the latter the terminal ones; both are bound to the cell surface via a glycosylphosphatidylinositol link. DAF but not CD59 could be demonstrated on FDCs. DAF is also present on the FDCs in follicular lymphomas despite the absence of complement (C3) in neoplastic follicles. This indicates that DAF is constitutive to FDCs but does not preclude the possibility that its expression is increased when immune complexes are deposited.

Antigens, CD↗

An immunohistochemical study of canine disseminated aspergillosis.

An immunohistochemical study of 25 lesions from 7 dogs with disseminated aspergillosis (Aspergillus terreus) is presented. All had multiple fungal granulomas in many viscera, with centres of necrotic tissue and hyphal elements surrounded by a mixed infiltrate of predominantly mononuclear cells. Within these lesions, hyphae coated with immunoglobulin (IgG, IgM, IgA) and complement (C3, C4) were identified, together with peri-lesional mononuclear cells that reacted with antisera directed towards either IgG, IgM, IgA or a T lymphocyte marker (MUII). A conspicuous feature was the prominent hyphal fluorescence seen with IgA and C3 antisera. The IgA reagent also marked large numbers of mononuclear cells both around lesions and scattered throughout interstitial tissue, suggesting an abnormality of IgA production or regulation as a factor predisposing to this condition.

Animals↗

IgE class immune complexes in Felty's syndrome: characterisation of antibody activities in isolated complexes.

By means of a double polyethylene glycol (PEG) precipitation and PRIST technique IgE was detected in 3% PEG precipitates and in the immune complex enriched fractions purified by solid-phase Clq adsorption from sera of 11 of 20 patients with Felty's syndrome. No correlation was found between the occurrence of complexed IgE and total protein content of the immune complex enriched material. IgE rheumatoid factor and anti-IgE antibody activity were detected in some of the immune complex fractions. Serum levels of complement C3, C4, and factor B were low in IgE immune complex positive cases. Only 4 of 20 patients with articular rheumatoid arthritis had IgE-containing immune complexes.

Aged↗

Glomerular localization of nephritogenic protein complexes on a nonimmunologic basis.

BACKGROUND: In a preliminary study, we have found that a group of charge-distinct protein molecules can react with each other to form protein complexes in vitro. The present study was conducted to determine the nephritogenic effect and the mode of action of these proteins in vivo. EXPERIMENTAL DESIGN: To demonstrate the precipitating interactions, a phosphorylcholine (PC)-conjugated, cationized bovine serum albumin (BSA(+)-PC) was applied to react with dinitrophenyl (DNP)-protein conjugates by double diffusion test. The types of forces involved in binding actions were determined. The experimental groups of CDF1 mice were injected simultaneously with BSA(+)-PC and individual DNP-protein conjugates through the tail vein. Both clearance kinetics and renal tissue studies were performed. RESULTS: BSA(+)-PC was able to form precipitin lines with respective DNP-protein conjugates in the agarose gel without any antigen-antibody interactions. These precipitating reactions were partially prevented by the presence of either NaCl, urea, or trifluoroacetate, suggesting that electrostatic force, hydrogen bond, and/or hydrophobic force are involved in the precipitation of these modified protein molecules. The clearance kinetics of BSA(+)-PC/BSA-DNP, and BSA(+)-PC/DNP-apoferritin showed a significant acceleration of the rapid phase of elimination. All of the experimental mice had hematuria and systemic thrombotic microangiopathic changes 1 hour later. By immunofluorescence, both the BSA(+)-PC and the DNP-protein conjugate injected were present in the renal glomerular tufts of experimental groups, although these protein molecules failed to deposit in the glomerulus when injected alone. Concomitant fibrinogen deposition was noted in almost all of the glomeruli affected. Moreover, 10 to 50% of the glomeruli examined 4 hours after injection had deposition of the third component of complement (C3). CONCLUSIONS: These data strongly support a hypothesis that nondeposited nephritogenic protein molecules in a fashion of heterogeneous complexes can localize in the glomerulus, thereby initiating renal injury, with the lack of antibody involvement.

Animals↗

Identification of MCP/CD46 analogue on bovine erythrocytes using the new monoclonal antibody IVA-520.

MCP/CD46 is a widely distributed C3b/C4b binding regulatory glycoprotein of the complement system that has been identified on all human peripheral blood cells except erythrocytes. In this paper, we describe the identification of bovine CD46 on all blood cells, including erythrocytes, with the newly prepared monoclonal antibody IVA-520. This antibody cross-reacts with human and pig cells. Furthermore, the molecule identified by IVA-520 functionally behaves as the MCP molecule, showing cofactor activity for the factor I-mediated cleavage of bovine C3 complement factor.

Animals↗

[Autoantibodies in vitiligo. Clinical significance].

The occurrence of circulating autoantibodies was determined by indirect immunofluorescence in patients with vitiligo. In addition we determined the existence of anti-melanocytic antibodies by an immunofluorescence complement fixation technique, immunoglobulins in achromic and perilesional skin, complement (C3 and C4) and immunoglobulins in serum by immunoelectrophoresis. The results only indicate that a significant occurrence of circulating autoantibodies exists, especially antithyroid autoantibodies, which, moreover, are related to the vitiligos which affect important areas of the cutaneous surface (generalized vitiligo).

Autoantibodies↗

Expression of complement regulatory molecules and other surface markers on neutrophils from synovial fluid and blood of patients with rheumatoid arthritis.

In an effort to elucidate the activation status of neutrophils (PMN) in inflammatory joint disease the expression of relevant cell surface proteins was examined using immunofluorescence and flow cytometry. Paired samples of SF and peripheral blood were obtained from 18 patients with RA and PMN purified using methods designed to minimize activation in vitro. We then used flow cytometry to measure expression of the four membrane complement regulatory molecules, decay accelerating factor (DAF; CD55), complement receptor 1 (CR1; CD35), membrane cofactor protein (MCP; CD46) and CD59; two adhesion molecules of the integrin family LFA1 (alpha chain, CD11a), complement receptor 3 (CR3; alpha chain, CD11b), and their common beta chain (CD18); the major receptor for immune complexes Fc gamma RIII (CD16), and the leucocyte common antigen tyrosine phosphatase (L-CA; CD45). Expression of these molecules was also measured on peripheral blood PMN from 18 age- and sex-matched normal controls. In RA, SF PMN expressed significantly higher levels of the complement regulators CD55 and CD35, the adhesion molecule CR3 (CD11b/CD18) and of CD45 but significantly lower levels of CD46 and CD11a in comparison with blood PMN from the same patient. Expression of CD59 and CD16 did not differ between the two groups. These changes may increase adhesiveness and complement resistance of PMN in SF compared with blood. PMN from RA expressed significantly less of all the complement C3 convertase regulators (CD55, CD46, CD35), all the adhesion molecules (CD11a, CD11b, CD18) and the phosphatase CD45 than did blood PMN from age and sex-matched control individuals.

Adult↗

Bactericidal activity of ascitic fluid in patients with nephrotic syndrome.

Patients with nephrotic syndrome are unusually susceptible to infections, including primary peritonitis. In this study, we have evaluated nine adult patients with nephrotic syndrome and ascites for ascitic fluid bactericidal activity, complement and immunoglobulin concentrations. Eight of nine patients had diminished ascitic fluid bactericidal activity while twelve control peritoneal fluids had normal bactericidal activity. Complement (C3 and C4) and immunoglobulin (IgG and IgM) concentrations were significantly lower in nephrotic syndrome ascitic fluid than peritoneal fluid from normal subjects. These findings may explain the high occurrence rate of primary peritonitis in nephrotic patients with ascites.

Ascitic Fluid↗

Effect of corticosteroid treatment on various serological & bronchoalveolar lavage abnormalities in patients with sarcoidosis.

Effect of daily oral prednisolone treatment was studied in 29 patients with pulmonary sarcoidosis. Twenty normal control subjects were also studied. Pretreatment absolute lymphocyte counts and proportion of lymphocytes in peripheral blood were significantly lower in patients with sarcoidosis as compared to normal controls. Total cell count and the proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid were significantly higher in sarcoidosis. The proportion of CD3+ and CD4+ was significantly lower in peripheral blood and higher in BAL fluid in patients with sarcoidosis. Immunoglobulins (IgG, A and M) and complements (C3, C4 and CH50) were significantly higher both in peripheral blood and BAL fluid. Patients with sarcoidosis were treated with daily oral prednisolone (30 mg/day). Repeat studies were performed after an interval of 4-6 months in 20 patients with sarcoidosis. A significant increase in absolute lymphocyte counts in peripheral blood and decrease in the proportion of lymphocytes in BAL fluid occurred with prednisolone treatment. Proportion of CD3+, CD4+ and B cells increased in peripheral blood and decreased in BAL fluid. Complement and immunoglobulin levels revealed a significant reduction in peripheral blood and BAL fluid. It is concluded that patients with sarcoidosis have peripheral blood lymphopaenia and lymphocytic alveolitis. They have increased levels of complement and immunoglobulins both in the peripheral blood and BAL fluid. All these abnormalities show significant improvement with prednisolone treatment.

Adult↗

Effects of serum from HIV-infected subjects on the functional activity of polymorphonuclear neutrophils.

The oxidative capacity of polymorphonuclears neutrophils (PMN) was assessed in 17 subjects with asymptomatic infection (AI), 16 patients with acquired immnunodeficiency syndrome (AIDS) and 12 healthy normal subjects using a quantitative Nitroblue Tetrazolium (NBT) reduction test. The effect of the serum of patients on the functional activity of normal and patients' PMN was also investigated. The NBT reduction non stimulated and stimulated with zymosan particles in presence of normal serum was similar to normal controls in both groups of patients. The serum from 11 out of the 17 AI subjects (65%) induced an increase while the serum from 8 out of the 16 AIDS patients (50%) induced a diminution in the stimulated NBT reduction in normal and patients' PMN. Those effects did no, appear to be related to complement C3 and circulating immune complexes levels. These results are indicating that PMN of HIV-seropositive patients do not present an intrinsic disfunction and that the impact of serum factor/s affects the normal functionalism of these cells depending on the infection stages.

Adult↗

Obstructive lung disease in Behcet's syndrome.

Obstructive lung disease in two patients with Behcet's syndrome is presented. In both cases increased airways resistance, impaired PEF and FEV1.0 were found. In addition, diffusion capacity was slightly decreased in spite of enlarged total lung capacity and increased residual volumes. Both patients had mild hypoxaemia despite slight hyperventilation; a normal chest X-ray, and a decreased serum complement C3 level. Corticosteroids had a beneficial effect on VC in one of the two cases but failed to have any significant effect on the impaired ventilatory function in the other.

Adrenal Cortex Hormones↗