Development of a simple and rapid elisa of urinary cotinine for epidemiological application

Highly stereospecific polyclonal antibodies (anti-CN) to cotinine (CN), a major metabolite of nicotine, were prepared from rabbit antisera to CN-linked keyhole limpet hemocyanin (KLH) by removing the antibodies to KLH and to its binding regions of CN. This was achieved by using immunoadsorbents consisting of insolubilized KLH onto CNBr-activated-Sepharose 4B. A new simple and rapid enzyme-linked immunosorbent assay (ELISA) of urinary CN was developed using the anti-CN. A brief outline of the method is as follows: CN-bovine thyroglobulin complex is coated onto wells of microtiter plates (1 ng/well), and then aliquots of urine samples or standard CN solutions were added followed by appropriate dilution of the anti-CN. The bound anti-CN antibodies are quantified spectrophotometrically with horseradish peroxidase-labelled anti-rabbit IgG and 2,2'-azino-di (3-ethylbenz- thiazoline)-6-sulfonic acid. Measurement of CN concentration in urine samples can be read off on a calibration curve drawn by using standard CN solutions. The standard curve ranged from 1 ng to 4 μ g /ml with an estimated lower limit of sensitivity of 7-8 ng/ml, resulting in within/between-assay CV (coefficient of variation) of lower than 10%. The method allowed one to assay more than 40 samples in duplicate by using just one plate, and is thus easily applicable to epidemiological investigations into exposure status to tobacco smoke.

Effects of transfer of hybridomas producing various isotypes of immunoglobulins on the C1q metabolism in mice

In order to elucidate possible effects of immunoglobulin on C1q metabolism at the anabolic steps, serum C1q levels and C1q mRNA of peritoneal exudate cells (PEC) and spleen cells were measured in female BALB/c mice implanted intraperitoneally with complement-(C)-fixing IgG2b- or non-C-fixing class IgG3-producing hybridomas and/or with immunoglobulin-non-productive myeloma cells (p3x63-Ag.8.653)(myeloma 653)(2 x 10(6)/0.2 ml) or without any treatment as controls. In the IgG2b-hybridoma-treated mice, the serum C1q levels and C1q mRNA in PEC increased conspicuously as compared with those in the controls, but C1q mRNA in spleen cells was almost equal to that in the control mice. On the other hand, in the IgG3-hybridoma-treated mice, the serum C1q levels decreased significantly, but the extent of such decrease and the level of C1q mRNA in their PEC were almost equivalent to those in the myeloma 653-implanted mice. The serum C1q levels and C1q mRNA in PEC fluctuated similarly in mice injected intraperitoneally with highly purified IgG2b and/or IgG3 preparations. These results suggest some anabolic interaction, as well as catabolic interaction, between the C-fixing class of immunoglobulin and C1q.

Collagen cross-reactive antigen of Sarcocystis cruzi

Collagen cross-reactive antigenic substance(s) in Sarcocystis cruzi cysts were examined with immunologic techniques using anti-bovine collagen type-specific, but non-species-specific, antibodies. By immunoperoxidase test, anti-bovine collagen type-specific, but non-species-specific, antibodies. By immunoperoxidase test, anti-bovine type IV collagen antibody showed higher reactivity to the cysts than other antibodies tested. Cyst wall rupture was induced by collagenase treatment and digestion was inhibited with EDTA supplementation. With immunoblotting analysis, one band of the cyst extract, which exhibited specific reactivity to anti-bovine type IV collagen antibody, was detected. The band had a molecular weight of approximately 66 kDa. These results suggest that sarcocysts of S. cruzi may be comprised of bovine collagen type IV cross-reactive antigenic substances.

Seasonal distribution of adenoviruses, enteroviruses and reoviruses in urban river water

In the 63-month period from January 1988 to March 1993, monthly levels of adenoviruses, enteroviruses (coxsackie B, polio, echo) and reoviruses in the urban river water in Nara Prefecture, Japan were in the range 0-25, 0-190 and 0-325, plaque forming units per liter (PFU/liter), and the average levels were 2.4, 40.6 and 56.2 PFU/liter, respectively. The peak reovirus level was found in winter during the cold weather months (Nov. to Mar.). The peak enterovirus level was found in summer (May to Sept.) but continued to be found in autumn-winter (Oct. to Jan.) from 1991 to 1993. The levels of adenoviruses were low throughout all 5 years, as compared to those of reoviruses and enteroviruses. Polioviruses were isolated following the administration of vaccine. Although a changing pattern of serotype prevalence was seen with the coxsackie B viruses and echoviruses from 1988 to 1993, this is not so for polioviruses, which remained almost unchanged for the five-year period. Adenoviruses were isolated throughout all five years, though in small numbers. Reoviruses were isolated most frequently throughout five years.

Antiviral activity of trichothecene mycotoxins (deoxynivalenol, fusarenon-X, and nivalenol) against herpes simplex virus types 1 and 2

The effect of trichothecene mycotoxins, deoxynivalenol (DON), fusarenon-X (FX) and nivalenol (NIV), on plaque formation of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) in HEp-2 cells was examined. The 50% effective concentrations (EC50) of DON, FX, and NIV for HSV-1 plaque formation were 160, 56, and 120 ng/ml, respectively. Those for HSV-2 plaque formation were 94, 26, and 50 ng/ml, respectively. These three mycotoxins showed about 2-fold higher selectivity to HSV-2 than to HSV-1. Plaque formation of HSV-1 was not inhibited with trichothecenes at concentrations completely inhibiting plaque formation when cells were treated during virus adsorption period or 15 hr before infection. These results indicate that trichothecenes affect replication of HSV-1 after virus adsorption, but not before or during virus adsorption to the host cells.

Intraglomerular expressions of IL-1 alpha and platelet-derived growth factor (PDGF-B) mRNA in experimental immune complex-mediated glomerulonephritis

Both PDGF and IL-1 play important roles as autocrine growth factors for cultured mesangial cells, and may be closely associated with the progression of glomerulonephritis. In this study we investigated intraglomerular expressions of PDGF-B and IL-1 alpha mRNA in mice with bovine serum albumin (BSA) nephritis, a model of immune complex-mediated glomerulonephritis, using the reverse transcription-polymerase chain reaction (RT-PCR) method. We also quantified intraglomerular PDGF-B mRNA by the competitive PCR and studied the correlation between the level of intraglomerular PDGF-B mRNA expression and the degree of observed glomerular injury. While expression of neither PDGF-B nor IL-1 alpha mRNA was detected in glomeruli from control mice, both were strongly expressed in glomeruli from mice with BSA nephritis. IL-1 alpha mRNA in glomeruli showed low accumulation in mice with mild glomerular injury, and was increased in mice with moderate glomerular injury. In contrast, high intraglomerular expression of PDGF-B mRNA occurred in all mice with mild glomerular injury and continued throughout the course of the disease. We observed no correlation between the level of PDGF-B mRNA expression and the histologic grade of renal damage. These results suggest that PDGF and IL-1 have different growth properties, and PDGF might play a role as a competence factor rather than a progression factor in the pathogenesis of immune complex-mediated glomerulonephritis.

[Detection of immune complex by C1q solid phase enzyme immunoassay]

We have developed a new and improved method for detecting immune complexes (IC) by C1q solid-phase enzyme immunoassay (CSP-EIA). The sensitivity of this method was between 0.62 micrograms/ml and 1.25 micrograms/ml, and values in normal individuals were 1.8 micrograms/ml and less. The positive rate of IC of sera in which abnormal values were detected by autoimmune disease associated laboratory examinations was 50.0% in RA (2+), 20.4% in ANA (+), 60.0% in CH50 (less than 10), 41.7% in LE latex (+). In sera of RA (2+), the higher the value of CRP detected by a semi-quantitative analysis was, the higher the frequency having abnormal high IC values was. The number of IC positive sera, in which enzyme-linked immunoglobulins were detected, was 18 of 68 (positive rate 26.5%). The number of IC positive samples in asymptomatic carriers of sera, whose titer of anti-HTLV-I antibody was positive by gelatin particle agglutination assay (PA), was 14 of 67 (pos. rate 18.4%). All of these 14 samples were high positivity of anti-HTLV-I antibody (titer greater than or equal to 256 times). In urine of some patients with urogenital diseases, IC-like substances to show positive reaction by our CSP-EIA were detected. However, any positive reaction was not detected either by an anti-C1q- or an anti-C3d method. Studies are in progress to elucidate detailed characterization of the IC-like substances.

Expression of clumping and fibrinogen-binding activities of Staphylococcus aureus at various growth stages

Clumping and fibrinogen-binding activities of 4 Staphylococcus aureus strains (Cowan I, Newman D2C, Wood 46 and NCTC 5655) were assayed with a semiquantitative clumping test and an enzyme-linked immunosorbent assay (ELISA), respectively. Distinct positive clumping was detected with whole cells of the 3 strains except Wood 46. Amounts of fibrinogen required for a definite clumping depended greatly on strains as well as on their growth phases. On the other hand, fibrinogen-binding activities were detected both in culture supernatants and in cell lysates of all the 4 strains, and the levels were rather comparable with one another and relatively steady through their growth cycles. No significant correlation was thus found among expression behavior of clumping and fibrinogen-binding activities.

C1q, a collagen-like complement subcomponent, in dermatosparactic cattle: its extracellular modification is not affected by lack of procollagen N-terminal proteinase (pN-proteinase)

C1q, a collagen-like complement protein, was purified from the serum of a dermatosparactic calf which lacks procollagen N-terminal proteinase (pN-proteinase). The specific hemolytic activity of the serum C1q from the dermatosparactic animal was identical to that of C1q from a normal calf. Gel-filtration of serum from the dermatosparactic calf, on Sepharose 6B, showed the presence of C1q-antigenic material at only one position which was identical to the elution position of normal bovine C1q. No difference, under dissociating conditions, could be seen in the size of the chains of C1q in specific immunoprecipitates isolated from the sera of dermatosparactic and normal animals, as judged by polyacrylamidegel electrophoresis (PAGE) in the presence of sodium dodecyl sulfate (SDS). The C1q from the dermatosparactic animal showed the same N-terminal amino acid and tryptic-digest peptide pattern on HPLC as C1q from the normal calf. These results strongly suggest that pN-proteinase is not involved in the extracellular processing of C1q.

Pregnancy zone protein inhibits production of interleukin-2 but does not affect interleukin-2 receptor expression on T cell activation

The effect of pregnancy zone protein (PZP), which exhibits increased levels in the blood during pregnancy, on T cells was examined. PZP was found to suppress DNA synthesis following stimulation with phytohemagglutinin (PHA), concanavalin A (ConA) or CD3 antigen or in the mixed lymphocyte reaction (MLR). This effect of PZP was mediated by a reduction in interleukin-2 (IL-2) production, and was abolished by exogenous recombinant IL-2 administration. PZP did not affect the proliferation of T cells following stimulation with the calcium ionophore A23187 and phorbol 12-myristate 13-acetate (TPA). These results suggest that PZP acts on the T cell surface and reduces IL-2 production, but not IL-2R expression, and does not directly affect Ca2+ influx or protein kinase C.

Characterization of C1q found in a patient with hypocomplementemic vasculitis-urticaria syndrome

C1q, a subcomponent of the first complement component, of a 60-year-old female patient with hypocomplementemic vasculitis-urticaria syndrome (HVUS) was characterized. The C1q-precipitin activity (C1q-p) could not be detected by a routine method with 0.6% agarose in 10 mM Na-phosphate buffer containing 10 mM EDTA (pH 7.2). Hemolytic activity of her serum complement (CH50) and levels of C1 and C4 were significantly reduced at the exacerbation stage, but levels of other complement components were almost within the normal range throughout her clinical course. The specific activity of C1q at her exacerbation stage was significantly low, and its elution position on Sephacryl S-300 column was spread toward the low molecular weight in comparison with that of normal plasma. Molecular weights of the delayed fraction of C1q were estimated to be approximately 300,000 on the Sephacryl and 440,000 by the polyacrylamide gel electrophoresis (PAGE) containing sodium dodecyl sulfate (SDS) followed by immunoblotting, respectively. On reduction of her plasma, two bands with molecular weights equivalent to those of B and C chains of the normal C1q in an approximate molar ratio of 2:1 were immunostained. Plasma at her exacerbation stage showed only one precipitation line against anti-human C1q-antiserum which was completely fused with that formed between purified normal human C1q and the same antiserum. The probable structural change of the hypofunctional C1q in the case of this HVUS is discussed.

Antigenic determinants resulting from polymerization of immunoglobulin G

Antibodies against heat-aggregated human IgG (AHG) were raised in rabbits and those against immune complex (IC) of tetanus toxoid and its human antitoxin (T/aT) in rabbits and mice. These antisera were analyzed by the Ouchterlony double diffusion technique against native monomeric human IgG (NHG), AHG and chemically linked human IgG (poly-G). The appearance of neoantigens was demonstrated with human IgG bound to its corresponding antigen or denaturated nonspecifically. The results are indicative of the existence of a common determinant shared with AHG and T/aT, in addition to those of their own.

Opsonic effect of fibronectin on staphylococcal phagocytosis by human polymorphonuclear leukocytes: its relative inefficiency in post-phagocytic metabolic activities and in intracellular killing

The binding of 125I-labeled human plasma fibronectin (FN) to two strains of live Staphylococcus aureus (S. aureus) (a coagulase-positive Cowan I and a coagulase-negative Newman D2C) and the opsonic effect of FN on phagocytosis of these bacteria by human polymorphonuclear leukocytes (PMN) have been studied. 125I-FN bound to a similar extent in both staphylococcal strains. The 125I-FN-binding was significantly inhibited by human fibrinogen as well as unlabeled FN. The FN-binding was also reduced markedly by trypsinization of these bacteria, but the extent of its decrease did not correlate with their tryptic susceptibility of protein A and clumping factor. FN enhanced the uptake of these bacteria by PMN. However, its binding had no effect on superoxide anion (O2-) generation. The FN-binding definitely stimulated staphylococcal ingestion and intracellular killing by PMN, but the extent of such promotion was dissimilar between these two strains of bacteria. These results suggest that post-phagocytic metabolic activities as well as intracellular killing of these Staphylococci may also be greatly influenced by FN-unrelated factors as are other bacteria having no FN-receptors.

Complement subcomponent C1q in various strains of mice. Its serum content correlates with that of immunoglobulin G

The protein amount and the hemolytic activity of the initiating complement component (C1q) in the classical pathway, and the level of immunoglobulin G (IgG) in sera of various inbred mouse strains were measured in parallel with those in sera of closed colony mice. C1q levels were significantly high in male A/He and C57BL/10Sn mice, and conspicuously high in female C57BL/10Sn mice. In these strains and C57BL/6J mice of both sexes, IgG levels were also significantly high. IgG levels were strikingly high in female NZB mice and NZW mice of both sexes. On the other hand, both C1q and IgG levels were conspicuously low in BALB/c mice of both sexes and in male CBA mice, and surprisingly low in BALB/c-nu (nude) mice of both sexes. A significant correlation was observed between serum levels of C1q and IgG. The C1q specific activity, however, was equivalent in all serum samples with approximately 2 x 10(13) effective molecules/mg. The subunit composition of C1q analyzed by polyacrylamide gel electrophoresis was well comparable within all strains of mice tested. These results may suggest that mouse serum C1q does not have any phenotypic polymorphism.

Natural course of joint destruction and fluctuation of serum C1q levels in patients with rheumatoid arthritis

Using the number of joints with erosion in a total of 68 joints throughout the body, we studied a population of patients with rheumatoid arthritis whose disease duration was 10-15 years. Three groups, each showing a Poisson distribution, were found: the subset with least erosive disease (LES), the subset with more erosive disease (MES), and the subset with mutilating disease (MUD). The mean number of joints with erosion was 10.9 in LES, 32.2 in MES, and 53.5 in MUD. In LES, erosive articular changes were primarily limited to the peripheral smaller joints. In MES, the larger axial joints were also involved. Almost all joints were extensively damaged in MUD. During the early period of disease, differences between the 3 groups were highly significant in the rapidity of carpal bone destruction, as assessed by the yearly reduction of carpal height ratio (P less than 0.001), and in the serum C1q level (P less than 0.001).

Two proteins with gamma-carboxyglutamic acid in frog bone: isolation and comparative characterization

Two gamma-carboxyglutamic acid-containing proteins were purified from neutral (pH 7.5) EDTA-extract of frog, Rana catesbiana, cortical bone by Sephadex G-75 gel filtration, DEAE-Sephadex A-25 chromatography and successive hydroxyapatite column chromatography. These two bone gamma-carboxyglutamic acid-containing proteins, termed osteocalcin, P-1 and P-2, had molecular weights of about 5100 and 4900, respectively, based on their amino-acid composition. Both species of osteocalcin have two gamma-carboxyglutamic acid residues, one disulfide bond, but there was no 4-hydroxyproline in either molecule. Each N-terminus of both proteins was acetylated and each C-terminal amino acid was lysine. The isoelectric points of P-1 and P-2 are 4.02 and 3.91, respectively, and their pI values shifted to more neutral pH in the presence of calcium ions. Equilibrium dialysis has indicated that each of these two proteins binds specifically 2 mol Ca2+, and nonspecifically more, 4-5 mol, Ca2+ in 0.02 M Tris-HCl/0.15 M NaCl (pH 7.4), at 4 degrees C. By the best-fitted calculation, P-1 had one high affinity Ca2+-binding site (Kd1 = 0.17 mM) and one lower affinity site (Kd2 = 0.29 mM), and P-2 contained one high affinity site (Kd1 = 0.154 mM) and one lower affinity site (Kd2 = 0.67 mM).

Purification, identification and characterization of chicken C1q, a subcomponent of the first component of complement

A component, having the equivalent haemolytic activity to that of human complement subcomponent C1q, was purified by a combination of precipitation with EGTA, gel filtration, ion exchange and adsorption chromatography from chicken serum. Yields ranged from 8 to 15 mg/litre of serum. The finally purified preparation generates full Cl haemolytic activity when assayed with human complement subcomponents C1r and C1s, and have been identified as chicken C1q. The molecular weight of undissociated C1q, as estimated on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS), is 504,000. Under dissociating but non-reducing conditions, the C1q was shown to consist of 2 subunits having molecular weights of 52,700 and 51,200 in a molar ratio of 2:1. On reduction, the 52,700 molecular weight subunit gave chains with molecular weights of 25,900 and 24,800 in equimolar ratio, and the 51,200 molecular weight subunit decreased to 24,800. The C1q contains hydroxyproline, hydroxylysine, a high percentage of glycine and approximately 7% carbohydrate. Collagenase digestion of C1q caused a rapid loss of haemolytic activity and produced much smaller peptide fragments.

Serum C1q levels as a prognostic guide to articular erosions in patients with rheumatoid arthritis

C1q was measured serially by single radial immunodiffusion in 54 rheumatoid arthritis (RA) patients over a period of more than 5 years, and values were correlated with laboratory, radiographic, and clinical findings. The number of joints with erosion (NJE) was determined retrospectively from radiographs of patients who had RA of greater than 7 years duration. In patients with clinically "burned out" RA, C1q levels were not statistically different from those of healthy adults. During the period of active disease, each patient's C1q level remained very constant, irrespective of erythrocyte sedimentation rate, C-reactive protein (CRP) level, or whether the RA was active or in remission. No sustained correlation was found between the C1q level and the other 2 acute phase reactants, but patients with C1q levels of at least 250 micrograms/ml showed a positive CRP over a period of years, in contrast to those with C1q levels below 250 micrograms/ml. Patients with an initial C1q above 250 micrograms/ml had more erosive RA when compared with those having C1q levels below 250 micrograms/ml. These data suggest that active RA can be classified into two subsets by C1q levels, one with persistent inflammation and a high NJE and another without persistent inflammation and with a low NJE.

A study of the role of the asparagine-linked sugar chains of human complement subcomponent C1q in its biological activities

The sialic acid residues were removed from asparagine-linked sugar chains on the C-terminal non-collagenous globular regions of human C1q by sialidase digestion. Both the haemolytic activity and the binding ability to immunoglobulin G (IgG) (Fc-binding ability) of C1q were unimpaired, even after the complete removal of sialic acid from these sugar chains. On the other hand, the rate of disappearance of C1q from the circulation was greatly accelerated by its desialylation, that is, the radioactivity of the infused intact and desialylated C1q was reduced to half for 200 min and for 140 min in the circulation of rats, respectively. A mixture of entire asparagine-linked sugar chains consisting of neutral, monosialyl and disialyl oligosaccharides was isolated from the intact C1q molecule by hydrazinolysis. The oligosaccharide-mixture isolated, after NaBH4 reduction, was added to assay system of C1q, but neither the haemolytic activity nor the Fc-binding ability was influenced.

Comparative studies on biological activities of subcomponents C1q of the first component of human, bovine, mouse and guinea-pig complement

Both the haemolytic activity and the binding ability to immunoglobulin G(IgG) (Fc-binding ability) were comparatively assayed among human, bovine, mouse and guinea-pig C1q. The haemolytic activity was measured by using the sensitized sheep erythrocytes with rabbit immunoglobulin M(IgM)- or IgG-haemolysin. The Fc-binding ability was assayed by using immune complexes made of rabbit IgG-antibody against human serum albumin as well as agglutination of latex particles coated with human, bovine or rabbit IgG (IgG-latex). The specific haemolytic activity was comparable with between bovine and mouse C1q, while those of guinea pig and human C1q were significantly lower than those of the others. Only the human and mouse C1q showed significantly positive agglutinating activity of human or bovine IgG-latex. In the case of the use of rabbit IgG-latex, each of these C1q gave much weaker agglutination. On the other hand, the ability of all these C1q to bind to Fc of immune complexes specifically was almost comparable. The discrepancy in specific activities between the haemolysis and the Fc-binding ability may suggest that these two biological activities are not always correlative and that these are independent biological phenomena.

Antigenic interspecies cross-reaction of subcomponent C1q of the first component of complement: evidence for its cross-reaction in both collagen-like and non-collagen-like regions

Human, bovine, and mouse C1q, a subcomponent of the first complement component, were purified, and both globular (GF) and collagen-like fragments (CLF) were isolated from human and bovine C1q. Antisera were produced in rabbits with these C1q or fragments, and F(ab')2 of immunoglobulin G (IgG) was purified from the antisera in order to avoid the possible non-specific binding of C1q of these animals to the Fc portion of rabbit IgG. Immunodiffusion analyses and radioimmune inhibition tests with these F(ab')2 showed that the definitive antigenic cross-reactivity was among C1q molecules of these animals, and that the regions participating in interspecies cross-reactions were located in both GF and CLF of C1q. These results suggest that both the C-terminal non-collagenous globular and the N-terminal collagen-like domains of C1q molecules may have remained highly conserved during evolution.