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PubMed1981

In vitro studies on cellular and humoral chemotaxis in Crohn's disease using the under agarose gel technique.

The locomotor function of polymorphonuclear cells (cellular chemotaxis) and serum chemotactic activity (humoral chemotaxis) were studied in 51 patients with Crohn's disease using a method of migration under agarose gel. To study cellular chemotaxis patient's polymorphonuclear cells were challenged against normal Zymosan activated serum and humoral chemotaxis was evaluated testing the patient's Zymosan activated serum against normal polymorphonuclear cells. Cellular chemotaxis in the Crohn's disease group was normal (although 30% of the 51 patients had migration values out of the normal range), while humoral chemotaxis was significantly lower in Crohn's disease patients than in the control group. However, the value of humoral chemotaxis in the group of Crohn's disease patients treated with steroids was lower than that of patients not treated, thus accounting for the low mean value observed inthe Crohn's disease-group as a whole. The present results suggest that a defective chemotactic response may occur in some Crohn's disease patients, particularly during steroid treatment. These findings might be related either to a defective generation of complement derived chemotactic factors or to the presence of circulating inhibitors.

Adrenal Cortex Hormones↗
PubMed2004

Glomerular deposition and urinary excretion of complement factor H in idiopathic membranous nephropathy.

BACKGROUND/AIMS: The complement system plays an important role in the pathogenesis of membranous nephropathy (MN). In order to elucidate the regulatory mechanism of complement activation, we demonstrated glomerular deposition and urinary excretion of complement factor H, which controls the alternative pathway and the amplification loop at the C3 step, in patients with idiopathic MN. METHODS: Renal biopsy specimens from 20 patients with idiopathic MN were studied immunohistochemically using monoclonal antibodies against complement components including factor H. SDS-PAGE and Western blotting analysis of urine samples were performed, and the urinary excretion of factor H and C5b-9 were measured by quantitative sandwich ELISA. RESULTS: Intense glomerular deposition of factor H was observed with C3b.C3c and C5b-9 at an early stage of the disease. Factor H was detected in Western blots of urine samples, but factor H-like protein 1 (FHL-1) was not. The mean level of urinary factor H was elevated (86.30 +/- 21.93 U/mg urinary creatinine) in comparison to that of normal controls (4.76 +/- 1.03 U/mg urinary creatinine). Urinary factor H level exhibited no correlation with clinical parameters; however, a negative correlation was found between urinary C5b-9/factor H and creatinine clearance (r = 0.662, p < 0.01). CONCLUSION: The source of glomerular and urinary factor H is supposedly a 150-kD protein. There was no evidence to suggest that FHL-1 is synthesized at the site of inflammation. The urinary C5b-9 to urinary factor H ratio is indicative of the degree of ongoing complement activation in the glomeruli and complement-mediated renal injury. These findings suggest that factor H contributes to the control mechanism of in situ complement activation and prevents renal damage in idiopathic MN.

Alternative Splicing↗
PubMed1991

Analysis of proteins eluted from hemodialysis membranes.

To further investigate the types of interactions occurring between blood and hemodialysis membranes, proteins were sequentially eluted from used dialysers. Four different membranes (cuprophan, hemophan, cellulose acetate and polyacrylonitrile) were successively treated with a hydrogen bond cleaving agent (10 M urea), an ionic detergent destabilizing the hydrophobic interactions between apolar groups (SDS solution), and a hydroxylamine solution at alkaline pH to release postulated covalently bound C3 fragments. The eluted proteins were analyzed by SDS-PAGE and immunological techniques. Total protein determinations demonstrate different behaviour of the membranes as regards the 'protein cake'. Electrophoretic analysis suggests that qualitative and quantitative differences in the binding of the blood proteins are related to the membrane material. Complement fragment studies indicate that the complement activating potential of the dialysis membrane may not be determined by the availability of potential binding sites for activated C3b. An attempt is made to correlate these results with the biocompatibility concept.

Acrylic Resins↗
PubMedDate not supplied

Nutritional and immunological evaluations in cancer patients. Relationship to surgical infections.

Several reports provide evidence of the synergism between malnutrition and infection in hospitalized patients. In this study, preoperative complete nutritional assessment (NA) was performed to: 1) evaluate NA modifications in 21 controls with benign minor surgical diseases and in 71 surgical cancer patients; 2) determine the relative value of nutritional and immunological indicators in relation to the postoperative septic complications in cancer patients. The following parameters were used: percent weight loss/month, percent standard arm circumference, percent standard triceps skinfold; hematocrit, hemoglobin, serum proteins, albumin, iron, transferrin, ceruloplasmin, retinol binding protein (RBP); serum creatinine, urine creatinine, creatinine/height index, percent arm muscle circumference; peripheral lymphocytes, white blood cells, complement (C3c), skin tests. In the cancer group percent usual body weight, percent arm muscle circumference, hematocrit, hemoglobin, albumin, iron, ceruloplasmin, retinol binding protein, C3c and delayed hypersensitivity response (DHR) were significantly different from controls. Ceruloplasmin and DHR were the only tests significantly different in the cancer patients who developed postoperative infections. Duration of anesthesia and operative field contamination are other important causative factors which, if associated with malnutrition, may determine a higher susceptibility to infections in surgical cancer patients.

Adolescent↗
PubMed1988

Spontaneous glomerular immunoglobulin deposition in young Sprague-Dawley rats.

The frequency, age-onset and distribution of spontaneously deposited immunoglobulins (Igs) in glomeruli of Sprague-Dawley rats has been investigated. Groups of rats (n = 10) were examined at 4-7 day intervals from birth (presuckling) until 30 days of age. Findings were compared with circulating immunoglobulin concentrations in each age group. Immunoglobulins were undetectable in immature kidneys of newborn rats. However, as early as 5 days, scanty IgA and IgM deposits were observed predominantly in mesangial areas of mature glomeruli, corresponding to low circulating concentrations of these immunoglobulins. By contrast, glomerular IgG deposits were not observed until 21 days, despite relatively high concentrations of circulating maternal IgG from birth. Mesangial deposition of immunoglobulins increased with age. Absence of complement C3c or electron dense deposits associated with this mesangial localization suggests that immunoglobulins were not deposited as immune complexes. Accumulation of non-phlogogenic immunoglobulins in the mesangium of normal rats supports the concept that the mesangium is constantly perfused by circulating macromolecules and filtration residues. The results indicate problems of interpretation of the significance of endogenous immunoglobulin deposition in models of experimental glomerulonephritis, even in studies involving weanling rats.

Animals↗
PubMed2006

Serum proteomic fingerprints of adult patients with severe acute respiratory syndrome.

BACKGROUND: Severe acute respiratory syndrome (SARS) is an emerging infectious disease caused by a new coronavirus strain, SARS-CoV. Specific proteomic patterns might be present in serum in response to the infection and could be useful for early detection of the disease. METHODS: Using surface-enhanced laser desorption/ionization (SELDI) ProteinChip technology, we profiled and compared serum proteins of 39 patients with early-stage SARS infection and 39 non-SARS patients who were suspected cases during the SARS outbreak period. Proteomic patterns associated with SARS were identified by bioinformatic and biostatistical analyses. Features of interest were then purified and identified by tandem mass spectrometry. RESULTS: Twenty proteomic features were significantly different between the 2 groups. Fifteen were increased in the SARS group, and 5 were decreased. Their concentrations were correlated with 2 or more clinical and/or biochemical variables. Two were correlated with the SARS-CoV viral load. Hierarchical clustering analysis showed that a majority of the SARS patients (95%) had similar serum proteomic profiles and identified 2 subgroups with poor prognosis. ROC curve analysis identified individual features as potential biomarkers for SARS diagnosis (areas under ROC curves, 0.733-0.995). ROC curve areas were largest for an N-terminal fragment of complement C3c alpha chain (m/z 28 119) and an internal fragment of fibrinogen alpha-E chain (m/z 5908). Immunoglobulin kappa light chain (m/z 24 505) positively correlated with viral load. CONCLUSIONS: Specific proteomic fingerprints in the sera of adult SARS patients could be used to identify SARS cases early during onset with high specificity and sensitivity.

Adult↗
PubMed1989

Serum immunoglobulins, complement levels and lymphocyte subpopulations in phenytoin-treated epileptic patients.

The peripheral blood lymphocytes, serum immunoglobulins, C3 and C4 complement protein concentrations of 20 patients with idiopathic epilepsy who were receiving phenytoin were examined and compared with 30 healthy controls in order to obtain a detailed profile of the effects of the drug on the humoral and cellular immune systems. The T-lymphocyte subsets were identified using monoclonal antibodies. A significant decrease in suppressor T-cells (p less than 0.05) and an increase in the ratio of T-helper to T-suppressor lymphocytes (p less than 0.01) have been found. Furthermore, an increase in B-lymphocytes (p less than 0.01) and a significant rise in serum Ig M concentrations (p less than 0.05) have been observed. No significant changes in serum concentrations of Ig G, Ig A and complement proteins were detected.

Adolescent↗
PubMed1977

Immunoproteins in human brain tumor cyst fluids.

Quantitation of the concentration of immunoproteins in serum, and cystic fluids from six patients (three with cerebral astrocytoma and three with cerebellar hemangioblastoma) has been determined. The values for total protein, albumin, immunoproteins IgG, IgA, and IgM, and C3C (complement) in cyst fluid more closely correspond to serum than to cerebrospinal fluid values. Values for cyst fluid, cerebrospinal fluid, and serum were determined using albumin ratios in order to compare relative differences between fluids from these three compartments. Our data suggests that: 1) the major protein content of brain tumor cyst fluid is consequential to a transudative process from serum, and 2) that immunoglobulins IgG and IgA are present in higher concentrations in human brain tumor cyst fluids in comparison to IgM concentrations. These studies further question the concept of the brain as an "immunological privileged site", and may be of direct relevance to the investigation of the use of immunotherapeutic modalities as an adjunct after surgical tumor removal.

Adolescent↗
PubMed2001

Regulation of in situ complement activation via the lectin pathway in patients with IgA nephropathy.

The lectin pathway, which is initiated by mannose-binding lectin (MBL) and MBL-associated serine protease (MASP), is one of the possible routes to activate the complement cascade in immunoglobulin A (IgA) nephropathy. The purpose of this study was to elucidate the regulatory mechanism of the pathway. Levels of complement activation products and regulatory proteins were measured in sera from 27 patients with IgA nephropathy, and generation of fluid-phase complement activation products in the presence of pooled normal human serum was quantified to evaluate activation in vitro. Although there were no significant differences in the serum levels and in vitro activation between the MBL-MASP positive (n = 14) and negative (n = 13) groups, there were positive correlations between complement activation products (Bb fragment and C4d fragment) and regulatory proteins (factor H, C4-binding protein, and C1 inhibitor) in the MBL-MASP-positive group. Furthermore, immunohistochemical studies demonstrated glomerular deposition of the regulatory protein (C4-binding protein, alpha2-macroglobulin, and factor H) in all patients in the MBL-MASP-positive group. These findings suggest that the regulatory proteins control in situ complement activation via the lectin pathway immediately, and continuous activation due to inadequate control will lead to the advanced glomerular injury.

Carrier Proteins↗
PubMed1991

Clustering of integral membrane proteins of the human erythrocyte membrane stimulates autologous IgG binding, complement deposition, and phagocytosis.

Damaged or old erythrocytes are cleared rapidly from circulation. Because several common biochemical lesions can induce the clustering of integral membrane proteins, we have proposed that formation of microscopic protein aggregates in the membrane might constitute a cell surface marker that promotes removal of the defective/senescent cells. We demonstrate here that treatments that cluster integral membrane proteins in erythrocytes (1 mM ZnCl2, 1 mM acridine orange, and 0.35 microM melittin) induce autologous IgG binding, complement fixation, and phagocytosis by human monocytes in vitro. Removal of the clustering agents prior to incubation in autologous serum or cross-linking of cell surface proteins before addition of clustering agents prohibited the above response, while cross-linking after treatment with the clustering agents preserved the response even if the clustering agents were later removed. Furthermore, subsequent reversal of the chemical cross-link maintaining the clustered distribution also reversed the induction of IgG binding, complement deposition, and phagocytosis. Finally, by deleting or inactivating different steps in the phagocytosis pathway, the chronology of steps was shown to be: (i) integral protein clustering, (ii) IgG binding, (iii) complement deposition, and (iv) phagocytosis.

Acridine Orange↗
PubMed1990

A constitutive antibody in normal human serum directed against rabbit bone marrow cells: lack in parturients, neonates, and hematologic disorders.

Normal human serum effectively inhibits a bioassay for erythropoietin based on DNA synthesis by rabbit erythroid precursors. This heat-sensitive inhibitory activity is readily lost on dilution of serum, revealing the presence of erythropoietin-potentiating activity. Inhibitory activity is caused by a rapid cytotoxic effect on rabbit bone marrow cells; mouse cells are less sensitive. Cytotoxic activity is removed from serum by adsorption to protein A, is not expressed at 4 degrees C, and is neutralized by anti-C3c complement antibody. Cytotoxicity is inhibited by EGTA; the effect of EGTA is reversed by addition of Ca2+ ions. These findings show that cytotoxicity is exerted through an antibody via the classical pathway of complement-dependent cell lysis. Although serum from healthy, adult human donors consistently contains cytotoxic activity, no such activity is observed in most serum samples from neonates, parturients, and patients with severe anemia. Patients with polycythemia or chronic renal failure occasionally lack cytotoxic activity in their serum. Serum samples lacking cytotoxic activity were found to be deficient in the antibody component in 34 out of 35 cases examined. These results show that an antibody directed against rabbit cells is constitutively present in normal human serum but is absent in a number of pathologic situations as well as being absent in neonates and parturients.

Anemia↗
PubMed1989

The role of the complement system in the pathogenesis of multiple organ failure in shock.

The results of our experiments suggest that the development of MOF is the result of a concerted autodestructive inflammatory process affecting the endothelium which is probably triggered off by the complement system. The combination of two noxious events (application of a low dose of endotoxin during hemorrhagic shock) leads to an enormous intravasal activation of complement including formation of C5a and the deposition of active split products of C3 (C3a, C3b) in the tissue of lung, liver, small intestine and kidney. Histological examination revealed ARDS-like pulmonary changes with inflammatory microvascular lesions and granulocytic infiltration primarily in the liver and to a lesser degree in the intestines and the kidney. The severity of organic lesion closely correlated with the extent of complement deposited. This corroborates the clinical observation that pulmonary and hepatic lesions are always the first signs of MOF, no matter what kind of noxious influence (trauma or peritonitis) gave rise to its development (Mc Menamy, 1980). Which mechanisms are involved in the processes by which active split products of C3 cause damage to tissue? C3a possesses strong chemotactic forces which can bring about aggregation of granulocytes in the tissue. Deposition of C3b on the contrary may lead to the formation of the cytolytically active membrane-attack-complex with the result of direct cell damage. We did not find any severe organic lesion or deposition of complement in our controls (endotoxin only, hemorrhage only). Our results suggest that MOF is a sequel of a generalized, autodestructive, inflammatory process which results from a hyperintensive and uncontrolled humoral immunoresponse to noxious events.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaphylatoxins↗