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PubMed1993

Treatment of cancer chemotherapy-associated thrombotic thrombocytopenic purpura/hemolytic uremic syndrome by protein A immunoadsorption of plasma.

BACKGROUND: Chemotherapy-associated thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (C-TTP/HUS) is a condition involving thrombocytopenia, microangiopathic hemolytic anemia, and progressive renal dysfunction that develops in 2-10% of patients with a history of malignant neoplasms treated with certain chemotherapeutic agents. Pathogenesis of the disease may depend on the following: (1) generation of endothelial lesions in the kidney microvasculature, resulting from drug toxic effects and/or generation of small soluble circulating immune complexes (CIC), and (2) generation of autoantibodies and/or CIC that trigger aggregation and deposition of platelets around the lesions. METHODS: Extracorporeal immunoadsorption treatment of plasma (PROSORBA columns, IMRE Corporation, Seattle, WA) to remove immunoglobulin G and CIC was evaluated in 55 patients for the potential to induce significant clinical benefits (increase in platelet count, decrease in hemolysis, stabilization of renal function) and longer survival. RESULTS: Response to therapy was achieved in 25 of 55 patients examined. Response was associated with an estimated 1-year survival rate of 61%, as compared with an estimated survival rate of only 22% in those who did not respond (P = 0.0001). Patients whose malignant neoplasms were in complete or partial remission at the time of development of C-TTP/HUS had a significantly higher estimated 1-year survival rate (74%) as compared with a historic control group of patients receiving other treatments (22%, P = 0.0161). Clinical responses were correlated with normalization of serum levels of CIC and complement components C3c and C4. There were no side effects associated with 75% of treatments. Immunoadsorption therapy was associated with generally mild to moderate manageable side effects, such as fever, chills, nausea/vomiting, respiratory symptoms, pain, hypertension, and hypotension, which were reported in 25% of procedures. CONCLUSIONS: This multicenter study establishes protein A immunoadsorption as an effective and safe treatment for cancer chemotherapy-associated TTP/HUS, an otherwise fatal disease.

Adult↗
PubMed1991

TEM immunogold staining of C3 from plasma onto titanium oxides.

Immunogold staining in conjunction with TEM was used to observe C3 adsorption from plasma in relation to the underlying titanium structure of thermal, anodic, and electropolished oxides. Heat treatments and oxide thickness were found to have no significant effect on the adsorption behavior of C3, while surface oxide type possibly has. Surface concentration of C3 was found to be time- and plasma concentration-dependent. Evidence is given for the possible involvement of C3 in protein exchange, i.e., the Vroman effect. Diluted plasma resulted in a random distribution of gold colloids, whereas clustering occurred with undiluted plasma. Although C3 concentrations present on grain boundaries followed the same trend as that found on the surface, C3 was found to have a higher grain boundary than bulk concentration for 0.1% plasma.

Adsorption↗
PubMed1994

In vitro plasma protein adsorption and kallikrein formation on 3-mercaptopropionic acid, L-cysteine and glutathione immobilized onto gold.

3-Mercaptopropionic acid (MPA), L-cysteine (L-cys), and glutathione (GSH) monolayers were immobilized onto gold and used in in vitro protein tests. The surfaces were characterized with ellipsometry, static contact angle measurements, atomic force microscopy, and Fourier transform infrared reflection absorption spectroscopy (FT-IRAS). After incubations in human plasma and antibody solutions, the surface antisera binding patterns were determined with ellipsometry. Using serum instead of plasma, complement activation was studied in the same fashion. Activated coagulation Factor XII and kallikrein formation on the surfaces and in the plasma were studied using a kallikrein-specific colorimetric assay. 3-Mercaptopropionic acid indicated contact activation of coagulation but L-cysteine did not. Glutathione displayed low deposition of plasma proteins, large deposition of proteins from serum, and did not promote kallikrein formation. None of the surfaces could be attributed complement activating properties, as determined by antibody deposition. The present study demonstrates that surface biology in complex model systems can be conveniently studied in vitro through systematic and well defined surface modifications.

3-Mercaptopropionic Acid↗
PubMed1995

Systemic autoimmunity due to mercury vapor exposure in genetically susceptible mice: dose-response studies.

Six groups of genetically mercury-susceptible female SJL/N (H-2s) mice were exposed to mercury vapor at a concentration of 0.3-1.0 mg Hg/m3 air for 0.5-19 hr/day 5 days a week for 10 weeks. The absorbed doses were calculated to be between 75 and 2365 micrograms Hg/week/kg body wt (micrograms Hg/week/kg). The correlation between the dose and the concentration of Hg in kidney, spleen, and thymus was highly significant (p < 0.0001; Spearman's rank correlation test). The lowest observed adverse effect level (LOAEL) for serum IgG antinucleolar antibodies (ANoA) was 170 micrograms Hg/week/kg, corresponding to a renal mercury concentration of 4.0 +/- 0.76 micrograms Hg/g wet wt. The correlation between the absorbed dose and the ANoA titer was highly significant (p < 0.0001; Spearman's rank correlation test), and all mice were ANoA-positive at a dose of 480 micrograms Hg/week/kg. High-titer ANoA targeted the nucleolar 34-kDa protein fibrillarin. The LOAEL for B-cell stimulation, measured as an increase in serum IgG2a and IgG1 concentrations, was 360 micrograms Hg/week/kg, but the increase was fivefold higher and also included IgE at a dose of 690 and 2365 micrograms Hg/week/kg. The serum Ig concentrations peaked after 2-4 weeks and then slowly declined but, except for IgE, remained significantly increased during the entire exposure time. Glomerular, mesangial IgG immune complex (IC) deposits, accompanied by systemic vessel wall IC deposits, were first detected at a dose of 480 micrograms Hg/week/kg. The mesangium also showed increased titers of IgM IC deposits and complement factor C3c. The correlation between the absorbed dose, and the individual titer of IgG, IgM, and C3c, was highly significant (p < 0.0001; Spearman's rank correlation test). In conclusion, mercury vapor efficiently induced an autoimmune syndrome in genetically susceptible mice, and the LOAEL for the adverse effects varied in the order ANoA < B-cell stimulation < IC deposits. Comparing the body burden of mercury in mice at the LOAEL for autoantibodies with the body burden in populations of occupationally exposed humans suggests that the safety margin may be narrow for genetically susceptible individuals.

Administration, Inhalation↗
PubMed1991

Fungal cell adhesion molecules in Candida albicans.

Adherence of Candida albicans to host tissues is considered a crucial step in the pathogenesis of candidiasis. Using in vitro assays, it was demonstrated that the yeast-mycelium transition was an important phenomenon in the acquisition of adhesive properties. Proteins with MWs of 60, 68, 200 and greater than 200 kDa seemed to be involved in germ tube adherence to plastic surfaces. Likewise, recent investigations have revealed that C. albicans expresses on its surface receptors which interact with a wide variety of host proteins, particularly some extracellular matrix components like fibronectin, laminin and collagen. Plasmatic components, such as fibrinogen, iC3b and C3d, have also been proposed as mediators of adherence of C. albicans. Thus, by their reaction with laminin, fibrinogen and C3d, the mannoproteins of 68 and 60 kDa demonstrated multiple biological activities. Proteins of similar MWs were detected as C3d and iC3b receptors, the latter showing similarities with the neutrophil CR3. Based upon the antigenic, structural and functional homologies between the candidal receptors and mammalian integrins, it was postulated that these fungal cell adhesion molecules (F-CAM) are members of the integrin family. Interactions with host proteins and molecular mimicry of mammalian adhesion molecules may be a fertile area for further research.

Basement Membrane↗
PubMed1991

Complement C3, coeruloplasmin and PMN-elastase in the ejaculate in chronic prostato-adnexitis and their diagnostic value.

The clinical differential of chronic prostatitis and psycho-vegetative urogenital syndrome with objective laboratory tests is very difficult. 265 ejaculates with possible chronic prostatitis were bacteriologically examined (including the search for STD agents). To verify an inflammatory process in the prostate and adnexae, we tested the C3 complement, coeruloplasmin and PMN-elastase levels in ejaculate. In addition, semiquantitative leucocyte counts in stained smears of the ejaculate were carried out. 185 of 265 patients had C3 complement below detection levels or in the normal range excluding inflammation of prostate or adnexae. 16.8% of the C3-negative ejaculates showed an elevated PMN-elastase level associated with urethritis anterior and/or posterior caused by STD agents. 80 patients showed elevated C3 levels; 38.8% with elevated coeruloplasmin and PMN-elastase levels. The semiquantitative leucocyte count in the stained smear proved the least sensitive method for verifying an inflammation. Enterococci (55.3%), Mycoplasma (18.8%) and Escherichia coli (16.5) were the dominant pathogens of chronic prostatitis present in number of 10(2) cfu/ml or greater than 10(5) cfu/ml. A correlation to the intensity of the inflammation was not found. These results show how important it is to realise a complete bacteriological examination as well as to determine the C3 complement, coeruloplasmin and PMN elastase.

Adult↗
PubMed1985

Activity of circulating monocytes in patients with chronic glomerulonephritis.

Monocytes of 95 patients with chronic glomerulonephritis (ch.g.) tested in vitro demonstrated characteristics of activation in proliferative, and of functional suppression in mesangiocapillary glomerulopathy. Fc and C3 receptor function studied by rosette assay and metabolic potential measured by the NBT reduction test constituted result patterns. Receptor tests were supplemented with their counterparts after monocyte triggering with heat-inactivated sera and in case of NBT assay - stimulation with zymosan. Membranous, minimal change, mesangial and focal glomerulonephritis monocytes presented less specific configurations of data than those of proliferative and mesangiocapillary, with a uniform increase of trypsin-resistant Fc receptor activity. There was no appreciable correlation between the presence of circulating immune complexes (c.i.c.) in patient sera and parameters tested. The mesangiocapillary "suppression pattern" suggests mononuclear phagocyte defect in this glomerulopathy.

Adolescent↗
PubMed1995

[Chronic bullous dermatosis in childhood. Association with salmonella enteritis].

We report on a 2-year-old girl with chronic bullous disease of childhood (CBDC). Concomitantly with a feverish gastrointestinal infection caused by Salmonella enteritidis, the child presented with lesions resembling impetigo contagiosa on the legs and face. Following antibiotic treatment with cephalosporins p.o. and flucloxacillin i.v. she developed typical symptoms of CBDC, i.e. tense blisters on erythematous skin in the perineal area, on the flexor aspects of the thighs and upper arms and on the face. Direct immunofluorescence revealed a linear IgA deposition along the basement membrane zone, confirming the diagnosis of CBDC. These lesions cleared rapidly after treatment with dapsone p.o. This case prompted us to consider new aspects of the pathogenesis, clinical entity and treatment of this rare bullous disease of childhood.

Anti-Bacterial Agents↗
PubMed1999

Low serum C3, leukopenia, and thrombocytopenia: unusual features of henoch-schonlein purpura.

Henoch-Schonlein purpura (HSP) affects predominantly the skin, joints, gastrointestinal tract and kidney. Although the pathogenesis is probably of immune origin and complement activation is thought to play a role, laboratory findings including the serum level of the complement components are usually normal. We present a patient with a severe form of HSP nephritis who had unusual laboratory findings of a low level of C3, mild leukopenia and thrombocytopenia. These findings may further support the importance of complement activation in the pathogenesis of HSP.

Biopsy, Needle↗
PubMed1994

Estrogenic effects of the antiprogestin onapristone (ZK98.299) in the rodent uterus.

OBJECTIVE: Our purpose was to assess the estrogenic action of onapristone (ZK299). STUDY DESIGN: Three rodent models of estrogen action in the uterus were used. Deoxyribonucleic acid synthesis in the uterine epithelium of neonatal mice was determined by thymidine autoradiography. In adult ovariectomized mice uterine wet weight and progesterone receptor and estrogen receptor concentrations were determined. In immature rats uterine deoxyribonucleic acid synthetic activity was determined by thymidine autoradiography, epithelial hypertrophy and stromal edema were assessed histomorphometrically, and complement C3 protein synthesis was assessed by metabolic labeling in vitro. The effects of ZK299 were challenged with the antiestrogens ICI164,384 and tamoxifen. The ability of ZK299 to displace tritiated estradiol from the estrogen receptor was assessed in cytosolic preparations from mouse uterus. RESULTS: In the neonatal mouse ZK299 stimulated epithelial deoxyribonucleic acid synthesis; two other antiprogestins, RU486 and ZK98.734, had no effect. Three daily injections of ZK299 at 10 micrograms/gm body weight to 6-week-old ovariectomized mice increased uterine progesterone receptor 42%; this effect was blocked by ICI164,384. In another experiment three daily doses of ZK299 (20 micrograms/gm) to 10-week-old ovariectomized mice increased progesterone receptor concentration by 63% and uterine wet weight by 42%. In 21-day-old rats a single injection of ZK299 increased uterine epithelial deoxyribonucleic acid synthesis; this effect was blocked by tamoxifen. Both ZK299 and tamoxifen increased epithelial cell height and thymidine labeling in the stroma. ZK98.734 had no effect on epithelium or stroma. ZK299 also stimulated synthesis of complement C3 by uteri of immature rats. In competitive binding assays ZK299 exhibited weak relative binding affinity (0.05%) for mouse uterine estrogen receptor. CONCLUSIONS: ZK299 can act as a weak estrogen in the rodent uterus, most likely through a direct, low-affinity interaction with the estrogen receptor. Because estrogens may increase the risk for endometrial, breast, and liver cancer, caution is warranted in long-term administration of this drug to women.

Animals↗
PubMed1991

Elimination of immune precipitates from the rat corneal stroma: a histological study.

The pathogenesis of peripheral corneal lesions of immune aetiology, like Mooren's ulcer and catarrhal infiltrates, has been related to the formation or deposition of immune compkexes. The present investigation was undertaken to study the mechanisms involved in the elimination of immune precipitates from the cornea. Immune precipitates were induced by injecting human serum albumin (HSA) and rabbit anti-HSA serum into opposite sites of the rat corneal stroma. This resulted in a line-shaped opacity in the stroma, which remained visible by slit-lamp for 7 days, and disappeared without clinical signs of keratitis and uveitis. At the ultrastructural level, the immune precipitates were clearly visible. Keratocytes in the vicinity of the immune precipitates appeared activated, as suggested by their less flattened appearance and well-developed rough endoplasmic reticulum. The arrangement of the collagen fibrils was not affected. Cells with a macrophage-like morphology were also present and contained electron-dense material, closely resembling the precipitate, suggesting phagocytosis. Separate corneas were injected with latex beads, which is known to induce migration of Langerhans cells into the cornea. Immunohistochemical analysis revealed that both latex beads and immune precipitates induced migration of macrophages (ED1+) into the rat corneal stroma. However, differences were observed with regard to the expression of MHC class II antigens by these ED1+ cells and the presence of complement deposits in the corneal stroma. ED1+ cells in corneas injected with latex beads were all MHC class II positive (OX4+), whereas most of the ED1+ cells at the site of the immune precipitates were negative (OX4-).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Schistosoma mansoni: surface membrane stability in vitro and in vivo.

The human complement component C3b is known to bind in vitro to the surfaces of all developmental stages of schistosomes as a consequence of complement activation by the alternative pathway. C3b bound to Schistosoma mansoni parasites has now been used in combination with fluorescent labeled antibodies against C3b to label the surfaces of living schistosomes. Binding of complement components and labeled antibodies to adult schistosomes rendered their surface membrane homogeneously fluorescent. At the ultrastructural level, the label was seen as a dense deposit lying on the tegumental membrane. Surface damage was not observed in labeled adults by electron microscopy. Fluorescent schistosomes were cultured in vitro for periods of up to 2 weeks, during which time the parasites remained fully viable and their surface membrane was still fluorescent. The electron dense deposit persisted, and tegumental damage at the electron microscope level was minimal or absent. Consequently, adult schistosomes would seem able to survive in vitro in the absence of rapid and general turnover of their surface membrane. Loss of fluorescence was observed consistently only at the anterior end of the parasite, including the suckers, a finding which indicates that membrane turnover may occur at different rates on different parts of the body. Fluorescent 3-week-old juveniles and 6-day-old lung stage parasites were cultured under the same conditions with similar results: they remained viable and fluorescent for at least 2 weeks. Results with skin schistosomula were different in the sense that many worms died during culture, and those which survived lost large parts of their fluorescent surface. A few of the surviving and fluorescent schistosomula developed the elongate shape typical of lung stage parasites. Fluorescent viable skin schistosomula were injected intravenously into mice and subsequently recovered from the lungs after varying periods. Fluorescence was lost in a patchy way within a few minutes from some individuals and within several hours from most of the worms. These data permit the following conclusions: C3b is a suitable tracer for membrane renewal in all developmental stages of schistosomes. Very slow membrane renewal in vitro and very rapid renewal in vivo are both compatible with parasite survival.

Animals↗
PubMed1993

Endogenous complement C3 synthesis in immune complex nephritis.

Human renal epithelial and mesangial cells have been shown to synthesise complement C3 in culture, but the relevance of this finding to the development of complement-mediated nephritis is uncertain. We investigated C3 gene expression in tissue biopsies that showed three main categories of renal injury. By semiquantitative polymerase chain reaction, biopsies from patients with immune-complex glomerulonephritis and those with cell-mediated interstitial nephritis showed increased C3 expression (p < 0.05), but biopsies from patients with non-immune glomerular injury did not. These findings suggest that local C3 production is enhanced in immune-mediated nephritis and are consistent with the hypothesis that locally synthesised complement components are involved in the pathogenesis of tissue injury.

Complement C3c↗
PubMed1993

Regulation by sulphonate groups of complement activation induced by hydroxymethyl groups on polystyrene surfaces.

Reducing the complement-activating capacity of a polymer surface is important in improving its blood compatibility. Polystyrene surfaces bearing hydroxymethyl (CH2OH) groups activate the alternative pathway of complement. This activation depends strongly on the density of the groups. Polystyrene surfaces bearing sulphonate (SO3-) groups adsorb proteins, resulting in an apparent activation. Polystyrene surfaces bearing both types of groups in close proportions are not activators in human serum, due to the adsorption of a protein of the alternative pathway, which has a protecting effect, not found when a polymer surface bearing hydroxyl groups is mixed in serum with another polymer surface bearing SO3- groups. In the presence of purified proteins of alternative pathway, C3 convertase activity can be created on each of these surfaces by deposition of C3b, but their susceptibility to inactivation by regulatory proteins H and I depends on the types of chemical groups present on the surface and whether the surfaces were passivated or not before C3b deposition.

Adsorption↗
PubMed1994

Adhesion of coagulase-negative staphylococci and adsorption of plasma proteins to heparinized polymer surfaces.

Protease treatment of cells of coagulase-negative staphylococci reduced the adhesion of bacteria to heparinized polyethylene preadsorbed with serum. Fibronectin (Fn), fibrinogen (Fg), vitronectin, complement factor C3c, plasminogen, laminin and to a low extent albumin were detected on tridodecylmethylammonium chloride (TDMAC)-heparinized polyvinyl chloride (PVC) catheters extirpated from the circulation of patients. Using a perfusion model we show that during the first hours of perfusion with human plasma, Fn and Vn dominate, whereas after 22 h of perfusion Fg is the dominant protein. Field emission scanning electron microscopy and atomic force microscopy studies on TDMAC-heparinized catheters as well as on end-point attached heparinized PVC catheters indicate that quantitatively more Fg than Fn is exposed on these surfaces after prolonged exposure (> 22 h) to human plasma.

Adsorption↗
PubMedDate not supplied

A potential vaccine for cocaine abuse prophylaxis.

Presently, there are estimated to be 1.5 to 2.0 million individuals infected with HIV-1 in the U.S. and about 12 million worldwide. In the U.S. over 90% of reported cases of AIDS occurred among two subgroups, homosexual males and intravenous substance abusers (IVSAs). Currently, there is no anti-cocaine addiction medication available. In order to explore vaccination as an alternative means for protection against cocaine addition, we immunized inbred male Fisher rats with either cocaine emulsification in complete Freund adjuvant (CFA) or with cocaine conjugated with keyhole limpet hemocyanin (KLH), as carrier plus CFA. Animals were initially immunized with 0.1 mg/animal of cocaine or cocaine-KLH. Animals were given a booster with the corresponding agents after 4 weeks. Ten animals/group were used. Controls received normal saline at the time of immunizations. These animals were injected, intraperitoneally, with 25 mg/kg of cocaine, and were examined for the analgesic effect of cocaine by the hot plate method. The average analgesic effect of cocaine was significantly reduced (p greater than 0.03) in animals immunized with cocaine-KLH (13.77 s) as compared to saline controls (21.6 s). Fifty percent of the animals (5/10) in the cocaine-KLH group and 33% of the animals (3/9) in the cocaine immunized group appeared completely resistant to the effect of cocaine on the central nervous system (CNS). We also have determined the levels of cocaine-specific antibodies produced by each animal by an ELISA method. Degree of protection from cocaine seems to correlate well with the amount of anti-cocaine antibodies produced by each animal (-0.61).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Serological findings in patients with allergic bronchopulmonary aspergillosis during remission.

The concentrations of total IgG, complement C3 and circulating immune complexes (CIC) were studied in 15 patients with allergic bronchopulmonary aspergillosis (ABPA) during remission and compared with those of 10 matched controls. The concentrations of complement and circulating immune complexes were similar to those of the controls but 33% of patients with ABPA in remission still had circulating immune complexes, mainly of IgG. Even so, the concentrations of IgG were significantly higher in patients during remission compared to controls but were lower than those observed during the acute stage of ABPA.

Acute Disease↗
PubMed1992

Urticarial vasculitis: a histopathologic and clinical review of 72 cases.

BACKGROUND: Urticarial vasculitis is a subset of vasculitis characterized clinically by urticarial skin lesions and histologically by necrotizing vasculitis. OBJECTIVE: A review of patients with urticarial vasculitis was undertaken to further characterize the clinical and histologic findings and to differentiate this disorder from urticaria and other types of cutaneous vasculitis. METHODS: Seventy-two cases of biopsy-proven urticarial vasculitis were selected for a review of medical records, laboratory data, and histologic findings. Fifty cases of simple urticaria were also reviewed for purposes of comparison. RESULTS: Systemic symptoms in patients with urticarial vasculitis included angioedema in 30 patients (42%), arthralgias in 35 (49%), pulmonary disease in 15 (21%), and abdominal pain in 12 (17%). Twenty-three patients (32%) had hypocomplementemia. Forty-six of 72 patients (64%) had lesions that lasted more than 24 hours, 23 of 72 (32%) had painful or burning lesions, and 25 of 72 (35%) had lesions that resolved with purpura. Sixteen biopsy specimens from the 23 patients with hypocomplementemia showed dermal neutrophilia in addition to the perivascular infiltrate. Of the 23 patients with hypocomplementemia, 20 (87%) had fluorescence of the blood vessels and 16 (70%) had fluorescence of the basement membrane zone as determined by routine direct immunofluorescence. CONCLUSION: Patients with hypocomplementemia were more likely to have systemic symptoms such as urticaria that resolved with purpura, arthralgias, abdominal pain, and chronic obstructive pulmonary disease. The histologic pattern associated with hypocomplementemia is interstitial neutrophilic infiltrate of the dermis and an immunofluorescent pattern of immunoglobulins or C3 in the blood vessels and along the basement membrane zone.

Biopsy↗