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PubMed1983

Activation of the complement system and accumulation of hemoglobin-haptoglobin complexes in plasma during an adverse reaction to penicillin treatment.

A patient treated with penicillin intravenously developed a serum sickness-like reaction. Classical pathway complement (C) activation was indicated by quantitation of the split products C3c and C3d as well as demonstration of C4 conversion. Circulating immune complexes could, however, not be detected by the solid-phase Clq and PEG-precipitation methods. A concomitant accumulation of circulating hemoglobin-haptoglobin complexes and a marked fall in serum-fibronectin concentrations suggested saturation of the reticuloendothelial system. The plasma became a deep-red color, and a diffuse intravascular coagulation followed. The patient recovered completely upon discontinuation of penicillin administration.

Antigen-Antibody Complex↗

PubMed1979

Positive direct antiglobulin test on thawed deglycerolized units of erythrocytes: prediction and prevention.

Occasional units of red blood cells develop a positive direct antiglobulin test (DAT) when frozen and deglycerolyzed by the Meryman method. The presence of cold autoagglutinins with a high titer at 4 degrees C or autoreactivity at room temperature were generally predictive of which units would develop a positive DAT, but neither was reliable in all cases. An indicator system is presented in which a DAT is performed on a segment that has been glycerolized and deglycerolized in a manner similar to the Meryman method for freezing a donor unit. This system is extremely reliable in predicting which units will convert from DAT-negative to DAT-positive during processing. The positive DAT of deglycerolized red blood cells was due to C4 and weak C3d binding. This complement binding can be prevented by addition of ethylenediaminetetraacetic acid (EDTA) or removal of plasma before the addition of glycerol.

Agglutinins↗

PubMed1994

CD21 antigen in T-lineage neoplastic lymphoid cells: characteristic expression at thymic stage.

The expression of CD21 antigen, a receptor for the C3d fragment of complement and Epstein-Barr virus (EBV), was investigated in a total of 85 cases of neoplastic lymphoid cells including 39 cases of T-lineage acute lymphoblastic leukemia (ALL)/lymphoblastic lymphoma (LBL), although CD21 antigen is usually regarded as a pan-B antigen. The CD21 antigen was expressed by one of the eight cases of neoplastic lymphoid cells expressing the CD7 antigen as a sole pan-T antigen, by three of the 20 cases of pro- or early thymic stage (CD7+ CD5+ CD2-, CD7+ CD5- CD2+, or CD7+ CD5+ CD2+, and ten of 11 cases of thymic stage (CD3+/- CD4+ CD8+), but not by one case of late thymic stage (CD3+ CD4+ CD8-) T-ALL/LBL cells. The CD21 antigen was not expressed by any of the 11 cases of adult T-cell leukemia (ATL) or two cases of chronic T-lineage leukemia. At most 4% of the normal thymocytes obtained from seven infants or children expressed the CD21 antigen. While only a very limited population of normal thymocytes expresses CD21 antigen, T-ALL/LBL cells at the thymic stage characteristically express CD21 antigen in contrast to pro- or early thymic ALL/LBL or peripheral-stage neoplastic T cells. The estimation of the expression of CD21 antigen is useful for delineating stages of differentiation in T-ALL/LBL. Furthermore, these observation are notable, considering the possibility that the reported EBV-carrying T-cell lymphomas result from the penetration of EBV into EBV-negative neoplastic T cells.

Adolescent↗

PubMed2005

Absence of NF-kappaB activation by a new polystyrene-type adsorbent designed for hemoperfusion.

AIM: The aim of the study was to evaluate biocompatibility of anew polystyrene-type adsorbent (BetaSorb) designed for hemoperfusion, using second-level biomolecular analyses. The device has recently been developed to enhance beta2-microglobulin removal during hemodialysis. Molecular structure and chemical modifications of the surface beads of this cartridge should prevent exposure of dense hydrophobic surface sites to proteins, and avoid the major drawbacks of previous polystyrene-type adsorbent materials. METHODS: Whole blood of healthy donors was incubated in sterile minicolumns packed with BetaSorb Cuprophan, Hemophan, polysulfone and cellulose acetate. In parallel experiments, whole blood was recirculated for 180 min in a sham dialysis circuit equipped with the study sorbent or Hemophan or polysulfone. Biocompatibility was assessed by means of new biomolecular approaches focused on nuclear factor kappaB (NF-kappaB) activation (assessed by electrophoretic mobility shift assay), TNF-alpha and IL-1beta gene expression (evaluated by real-time PCR), TNF-alpha and IL-1beta production (measured by Western blot assay and ELISA), nitric oxide (NO) generation (detected by electron paramagnetic resonance), free oxygen radical production (by chemiluminescence in a biological assay) and the generation of the complement breakdown product C3d. RESULTS: In coincubation experiments, 5-min contact with any dialysis device, but BetaSorb, was enough to induce activation of NF-kappaB. The amount of TNF-alpha precursor form was found to increase after 5 min of exposure to each tested polymer, but no traces of mature forms of TNF-alpha or IL-1beta were detected in in vitro experimental conditions using healthy blood. NO and free oxygen radical generation were significantly lower in blood samples exposed to BetaSorb than in control dialysis devices. C3d levels were found to be increased with Hemophan, unaffected by polysulfone, and remarkably decreased with the BetaSorb device. In the sham hemodialysis experiments, NF-kappaB activation and C3d and NO profiles were similar to direct incubation experiments. Compared to basal levels, quantitation of TNF-alpha and IL-1beta mRNA revealed a 15- and 9-fold increase, respectively, in samples exposed to Hemophan for 180 min. CONCLUSIONS: The new BetaSorb device not only appears to be highly biocompatible, but shares properties that make it probably able to interfere with the activation of the inflammatory state.

Adsorption↗

PubMed1990

Phase I clinical comparative study of monoclonal antibody KS1/4 and KS1/4-methotrexate immunconjugate in patients with non-small cell lung carcinoma.

A Phase Ia clinical trial was undertaken to evaluate and compare murine monoclonal antibody KS1/4 and KS1/4-methotrexate immunoconjugate in patients with Stage IIIB or IV non-small cell carcinoma of the lung. Six patients received KS1/4 alone and five patients received KS1/4-methotrexate conjugate. The maximal total dose received per patient in both groups was 1661 mg. Mild to moderate side effects in both groups included fever, chills, anorexia, nausea, vomiting, diarrhea, anemia, and brief transaminasemia. One patient who received antibody alone had an apparent acute immune complex-mediated reaction. Ten of 11 patients had a human anti-mouse response. Posttreatment carcinoma biopsies revealed binding of monoclonal antibody KS1/4 and deposition of C3d and C4c complement fragments. Monoclonal antibody binding and complement deposition correlated with increasing doses of infused antibody. There was one possible clinical response.

Adult↗

PubMed1989

[Immunologic parameters in patients with malignant melanoma].

In an attempt to better define the immunological reactivity of patients with malignant melanoma, the electrophoretic mobility of lymphocytes and their reactivity were studied in poly-L-lysine agglutination and in nucleolar test. Blood samples were examined before treatment and repeatedly after surgical removal of the tumor. A microagglutination test induced by poly-L-lysine was used for the detection of sensitized lymphocytes in peripheral blood of melanoma patients. The number of positive results was increasing with the progression of the disease. After incubation with poly-L-lysine the electrophoretic mobility of lymphocytes was changed in melanoma patients. The nucleolar test was used for the study of quantitative and morphological changes of the nucleoli in lymphocytes. Elevated values of the nucleolar coefficient and an increased number of active nucleoli provided evidence on the higher immunological reactivity of melanoma patients. The decline in the number of lymphocytes with ring-shaped nucleoli, signaling immunologic exhaustion, are of prognostic value. Lymphocytes were assayed also for the presence of receptors for sheep erythrocytes (E active and total rosettes) and C3d component of complement (EAC rosettes). The reported findings may be used to advantage in evaluating the immunological reactivity of melanoma patients.

Adult↗

PubMed1986

Circulating immune complexes in sickle cell anaemia.

Circulating immune complexes were investigated in sera of 100 patients with sickle cell anaemia (SCA) in different clinical stages, using inhibition of complement-dependent rosette formation (EAC rosette inhibition), anticomplementary activity, polyethylene glycol 6000 precipitation, immunoconglutinin titre, total haemolytic complement, C4 and C3d. A high positivity was observed in patients with hepatic crisis (75%) and cases with leg ulcers (43%) compared with painful crisis (12%) and asymptomatic (7%) patients. These results provide evidence for the presence of circulating immune complexes during leg ulcers and hepatic crisis in SCA.

Adolescent↗

PubMed1982

Anti-C1q column: ligand specific purification of immune complexes from human serum or plasma. Analysis of the interaction between C1q and immune complexes.

An efficient and reproducible procedure has been developed for the specific isolation of immune complexes. PEG precipitation of EDTA serum or plasma was an essential preliminary step to separate complex-bound from free C1q. PEG had no discernible effect on the molecular weight size of the extracted complexes. Redissolved complexes were incubated with a Sepharose-4B column coated with anti-human C1q antibodies and following removal of unbound material the bound complexes were sequentially eluted with 0.02 M EDTA, 0.5 M NaCl and 1 M propionic acid. Characteristics of the affinity column were established by the purification of 125I-labelled BSA-anti-BSA complexes and heat-aggregated IgG (HAGG) incubated in normal human serum (NHS). EDTA and NaCl eluted complexes were of similar molecular size and contained antigen, specific antibody, as well as human IgM, IgG, albumin, C3, C3c, C3d and C1q. Acid eluted complexes contained the highest yield of specific antigen and antibody and comprised in addition human C1q and C3d. Activation of complement components after C1q made the bond between C1q and immune complexes resistant to 0.5 M NaCl and interfered with the binding between solid phase anti-C1q and complex bound C1q. Using BSA-anti-BSA complexes and HAGG activated in NHS it was apparent that only a minority of the complexed material was isolated via the C1q ligand and this probably applies to the C1q binding assay. Most complexed material could be isolated using an anti-C3 affinity column.

Antigen-Antibody Complex↗

PubMed1982

Some immunological and biochemical markers in chronic lymphatic leukemia patients.

The leukemic cells in chronic lymphatic leukemia (CLL) patients have been studied prior to theory with a panel of immunological markers. Cells were assayed for the presence of receptors for sheep erythrocytes (E active and total rosettes), C3d component of complement (EAC rosettes), mouse erythrocytes (M rosettes), some of them also for surface membrane immunoglobulins (SmIg). In vitro 24 h cultures without mitogen (detection of spontaneous DNA synthesis) or 72 h cultures with phytohemagglutinin (PHA) were also performed. These conventional immunological markers and functional lymphocyte characteristics have been correlated with enzyme activities of adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP). Electrophoretic patterns of radiolabeled proteins under denaturing conditions (SDS-PAGE) have also been determined in some patients of this group. Phenotypic surface characterization of blood elements of all CLL patients studied revealed their B origin, with increased values of EAC rosette forming cells and especially increased values of M rosette forming cells. Significantly decreased values of both, ADA and PNP, were found in all the cases. Electrophoretic patterns of radiolabeled surface proteins from cells of CLL patients were essentially similar within the group with characteristically strongly radiolabeled glycoproteins gp44--HLA heavy chain and glycoproteins gp29, gp35--Ia-like or HLA-DR antigen.

Adenosine Deaminase↗

PubMed1981

Relevance of surface markers in chronic lymphocytic leukemia to acute lymphocytic leukemia.

The surface membrane of the B-lymphocyte of chronic lymphocytic leukemia (CLL) has been subject to detailed investigation over the past decade. Surface immunoglobulin of low density, punctate in distribution, without the tendency to polar cap formation, and clonal with respect to light and heavy chains, is characteristic. Other B-cell properties include the presence of the Ia antigen and the receptor for the C3d portion of complement. The CLL surface membrane lacks such T-cell attributes as the ability to form rosettes with sheep erythrocytes and reactivity with anti-T-cell antisera, although T-cells may be increased early in the disorder. CLL is believed to be a proliferation of a B-lymphocyte of the medullary cord of the lymph node, although the exact place of this cell in lymphocyte development remains to be clarified. Surface markers are useful in distinguishing classical B-cell CLL from other proliferations of small lymphocytes (lymphosarcoma cell leukemia of follicle-center B-cells, T-cell CLL, Sézary syndrome, and reactive lymphocytosis).

B-Lymphocytes↗

PubMed1986

Comparisons of pooled polyclonal rabbit anti-human C3d with four monoclonal mouse anti-human C3ds. II. Quantitation of RBC-bound C3d, and characterization of antiglobulin agglutination reactions against RBC from 27 patients with autoimmune hemolytic anemia.

Labelled polyclonal IgG anti-C3d and monoclonal IgM and IgG anti-C3d antibodies (MAs) were employed at increasing antibody excess to measure the number of C3d molecules on human red blood cells (RBC) coated by complement in vitro and in vivo. Values for the number of C3d sites per cell determined with polyclonal anti-C3d were at least 4-fold higher than when MAs were used. The results suggest that the molar combining ratio for polyclonal anti-C3d with a single RBC-bound C3d fragment is more likely greater than 4.0 than 1.0 as previously assumed. Antiglobulin agglutination studies compared polyclonal and monoclonal anti-C3d antibodies against C3d-coated RBC from 27 patients with autoimmune hemolytic anemia. All four MAs showed striking prozones, requiring their use over a 25-fold higher range of dilutions than polyclonal anti-C3d. Polyclonal anti-C3d produced stronger agglutination reactions than any of the IgG MAs. Only the IgM MA produced agglutination as strong as, or stronger than, polyclonal anti-C3d. While IgM MA always gave the strongest MA agglutination reactions, no consistent ranking of the three IgG MAs was observed. Agglutination was not enhanced when all IgG MAs were combined; addition of IgG MAs to IGM MA reduced the strength of agglutination seen with IgM alone, suggesting blocking of IgM binding by competing IgG anti-C3d.

Anemia, Hemolytic, Autoimmune↗

PubMed1985

Candida albicans and Candida stellatoidea, in contrast to other Candida species, bind iC3b and C3d but not C3b.

It was demonstrated that complement-coated sheep erythrocytes bind to Candida albicans cells grown in serum-free RPMI 1640 medium. Testing of purified complement components proved that iC3b and C3d were responsible for the reaction, whereas C3b and C3b-H reacted only slightly if at all. Binding occurred only to C. albicans and C. stellatoidea, not to other species pathogenic to humans. There was evidence of a lectinlike nature of the effect.

Animals↗

PubMed1983

[Paroxysmal nocturnal hemoglobinuria. Increase in proteins of the alternative complement pathway].

Increased activity of the complement alternative pathway proteins C3, B and H was found in the sera of 16 patients with paroxysmal nocturnal haemoglobinuria (PNH). This increased activity might depend on protein hypersynthesis secondary to in vivo low-grade complement consumption by abnormal erythrocytes in PNH patients, despite the fact that serum levels of C3d were found to be normal. B and H activities were directly related; however, the B/H ratio was higher in patients whose sera had been taken early after an episode of haemoglobinuria. Activation of the alternative pathway, which is known to result in vitro lysis of PNH erythrocytes, only accounts for part of the events leading to chronic haemolysis and haemoglobinuria in vitro.

Adult↗

PubMed1983

Interaction of fibronectin with complement component C3.

The activation of the complement component C3 generates C3a and C3b fragments, and the physiological cleavage of C3b further yields C3c and C3d fragments. We studied here by enzyme immunoassay the ability of human plasma fibronectin to interact with native C3 of human sera and with isolated C3c and C3d fragments of C3. C3 from sera of all six individuals tested bound to solid-phase fibronectin. Soluble fibronectin bound to solid-phase C3c and C3d, and fluid-phase C3c and C3d also bound to solid-phase fibronectin. The binding of fibronectin to solid-phase C3c and C3d could be inhibited by fluid-phase C3c and C3d. The results suggest the possibility that soluble fibronectin may attach to C3-coated particles or that C3-coated particles may adhere to fibronectin-containing structures.

Complement Activation↗

PubMed1984

Mechanisms of leukocyte regulation by complement-derived factors.

Progress over the past five years has drawn attention to the fact that the anaplylatoxins are important factors in both leukocyte activation and regulation events. The C5 anaphylatoxin has been proposed to play major role in leukocyte aggregation and adherence phenomenon. Influences of C5a on the leukocyte may lead to clinical manifestations such as respiratory distress syndrome after trauma or postpump syndrome after cardiopulmonary bypass, both effects derived from leukocyte sequestration. Many other clinical conditions involving repeated transient sequestration of leukocytes, particularly in the pulmonary vasculature, may eventually be recognized as a complication of systemic complement activation. Dramatic pathologic changes observed in the lungs of animals exposed to either C3a or C5a emphasizes the potential damage that these factors may exert via cellular activation mechanisms (Huey et al., 1983). More recent evidence that the anaphylatoxins are potent immunoregulatory factors under in vitro conditions suggests a physiologic role for these humoral factors in nonspecific modulation of the immune response. It is an attractive hypothesis to suggest that once activated, complement is capable of relaying information to the cellular immune system via the anaphylatoxins. Other components of the complement system have long been known to exert regulatory influences on the immune system, and perhaps molecular description of such entities as the C3d-K fragment will serve to unravel this seemingly more complex effector system. In any case, as our understanding of both the chemical and biologic nature of factors derived from blood complement components advances, it has become apparent that a major function of complement may be to modulate the immune response. We have already demonstrated that these factors are selective both for cell type and for eliciting a variety of cellular responses. From this, one can infer that manipulation of the cellular events will eventually be possible. Hence a therapeutic value may be realized once involvement of these complement factors under in vivo conditions is better characterized.

Anaphylatoxins↗

PubMed1987

Clinicopathological study of patients with mesangial isolated C3d deposition in various glomerular diseases.

The clinicopathological findings of isolated mesangial C3d deposition in the absence of other complement components or immunoglobulins are summarized. 55 out of 242 individual human renal biopsies examined by immunoperoxidase microscopy had isolated C3d deposition. This group consisted of 12 patients with chronic glomerulonephritis, 8 with minimal-change nephrotic syndrome, 32 with benign recurrent hematuria, 2 with Bartter's syndrome and 1 with Raynaud's syndrome. None of these patients had a disorder of the renal function and in all the patients the disease took a benign clinical course. Light-microscopic findings indicated injuries ranging from minor glomerular abnormality to mild diffuse mesangial proliferative glomerulonephritis, and there were no other remarkable findings such as cellular crescents, global sclerosis or interstitial infiltration. By immunoperoxidase microscopy, fine granular deposits of C3d were identified only in the mesangium, and arteriolar C3 staining was seen in 31 of the 55 patients. In 38 of the 42 patients examined by electron microscopy, electron-dense deposits were identified in the mesangial matrix. These findings suggest that isolated C3d deposition is a new entity with benign features both clinically and pathologically.

Adolescent↗

PubMed2003

Demonstration of apoptosis-associated cleavage products of DNA, complement activation products SC5b-9 and C3d/dg, and immune complexes CIC-C3d, CIC-IgA, and CIC-IgG in the urine of patients with membranous glomerulonephritis.

AIM: To investigate the involvement of complement activation and apoptosis in the pathogenesis of membranous glomerulonephritis by determining the concentrations of apoptosis-associated 180 bp nucleosomes and complement activation products SC5b-9 and C3d/dg in the urine of patients with membranous glomerulonephritis. METHODS: Morning urine was taken from 15 patients with immunohistologically established membranous glomerulonephritis. Apoptosis-associated 180 bp nucleosomes, complement activation products SC5b-9, C3d/dg, and immune complexes CIC-C3d, CIC-IgA, and CIC-IgG were detected in the urine samples by using antigen-specific enzyme-linked immunosorbent assay. RESULTS: Concentrations of measured parameters were expressed in units of standard deviation, ie, relatively to the average concentrations measured in healthy subjects. We found drastically increased concentrations of apoptosis-associated 180 bp nucleosomes (13.71+/-14.97; p=0.047), complement activation products SC5b-9 (197.07+/-134.88; p=0.003) and C3d/dg (38.70+/-43.35; p=0.048), and immune complexes CIC-C3d (11.01+/-13.39; p=0.74), CIC-IgA (7.93+/-4.38; p=0.001), and CIC-IgG (20.56+/-10.87; p=0.001) in the urine of patients with an active form of membranous glomerulonephritis. All studied molecules were absent, or present in very low concentrations, in healthy subjects and patients with membranous glomerulonephritis in remission. The mean differences between healthy controls and patients with the active disease were statistically significant in all parameters, except CIC-C3d. CONCLUSIONS: There is an association of complement activation and apoptosis with membranous glomerulonephritis. Correlation analysis suggests that the excretion of apoptosis-associated 180 bp nucleosomes, SC5b-9, C3d/dg, and immune complexes containing IgA and IgG in the urine of patients with active membranous glomerulonephritis does not depend solely on the passive transport together with other proteins, but is probably an independent active process.

Adult↗

PubMed1986

Immunohistochemical analysis of C3 cleavage fragments, factor H, and the C5b-9 terminal complex of complement in de novo membranous glomerulonephritis occurring in patients with renal transplant.

Fifteen renal biopsies from 13 transplanted patients with de novo membranous nephropathy (DNMN) were investigated by immunofluorescence for the presence of C5b-9 neoantigens of the terminal sequence of complement and for antigens expressed by C3 cleavage fragments. DNMN lesions were classified as stage I, II or III upon light and electron microscopy examination. Seven biopsies were classified as stage I DNMN and 8 stage II-III. All patients were proteinuric. In six biopsies with stage I DNMN, staining for C5b-9 neoantigens was restricted to a fine granular labeling in mesangial areas which was analogous to that seen in normal kidneys in contrast with extensive parietal labeling for IgG, C3d and factor H antigens. In eight biopsies with stage II-III DNMN, the pattern of staining with anti-C5b-9 neoantigens antibodies was similar to that obtained with anti-IgG, anti-C3d and anti-factor H antibodies. These results suggest that in situ activation of the whole complement sequence throughout C5b-9 only occurs on large immune deposits (stage II-III DNMN).

Adolescent↗