scholarly journals AN ALTERNATIVE MECHANISM FOR THE PROPERDIN SYSTEM

1958 ◽  
Vol 108 (4) ◽  
pp. 515-535 ◽  
Author(s):  
Robert A. Nelson
Keyword(s):  
N Uptake ◽  
Chelating Agent ◽  
Wide Distribution ◽  
Cross Reactivity ◽  
Normal Serum ◽  
Natural Resistance ◽  
Alternative Mechanism ◽  
Ancillary Data ◽  
Undiluted Serum ◽  
Human Sera

Evidence is presented that phenomena ascribed to the properdin system may be explained in terms of classical antibody (Ab) in combination with three of the components of complement (C'), i.e., C'1, C'4, and C'2 respectively. The results suggest that the complex of properdin (P) with zymosan (Z) represents a mixture of Z·Ab, Z·Ab·C'1, 4, Z·Ab-C'1, 4, 2, and Z·Ab·C'1, 4, 2 in a decayed state. The purported preferential reactivity of Z with the third component of C' (C'3) is not supported by the present experiments in which Z was reacted with C' in both guinea pig and human sera. Approximately the same number of reactive units of C'1, 4 and of C'3 were inactivated by Z, as well as by D. pneumoniae and a washed specific precipitate of bovine albumin-anti-albumin. The latter evidence that small amounts of antigen-antibody complex fix significant amounts of C'3 stands in contrast with the classical concept that C'3 is not fixed in ordinary complement fixation reaction. The observed reactivity of C'3 is explained on the basis of the present use of essentially undiluted serum as a source of C'3 and of 37° as the temperature for fixation. Ancillary data indicate that purified properdin contains Ab. In the presence of a chelating agent and at 0° properdin agglutinated Z granules. Measurements of nitrogen (N) uptake by Z suggest that 0.25 µg. N were contributed by solutions stated to contain 1 unit of properdin. The broad spectrum of reactivity or cross-reactivity of the Ab in normal serum is likely due to the wide distribution in nature of closely related polysaccharides. Further immunochemical studies are necessary to establish definitively the origin and mode of action in "natural resistance" of antibodies reactive with these polysaccharides.

STUDIES ON SULFATION FACTOR (SF) ACTIVITY OF HUMAN SERUM

1960 ◽  
Vol XXXV (III) ◽  
pp. 381-396 ◽  
Author(s):  
Sven Almqvist
Keyword(s):  
Human Serum ◽  
Normal Serum ◽  
Treatment Level ◽  
Response Curves ◽  
Normal Children ◽  
Significant Difference ◽  
Human Sera ◽  
Normal Humans ◽  
Pre Treatment ◽  
Dose Levels

ABSTRACT The sulfation factor (SF) activity of human sera has been estimated using a modification of the method of Daughaday et al. (1959). Each assay was statistically evaluated. The method had a mean precision of 0.14 and, used as an assay of GH of human serum, a sensitivity in three pituitary dwarfs of 0.1 to 0.6 μg of HGH/ml of serum. SF activity was found at all ages between 1 month and 75 years. There was a significantly lower mean SF activity below the age of half a year. Three cases of pituitary dwarfism had significantly low SF activities of sera. There was no significant difference between the SF activities of sera from untreated pituitary dwarfs and the sera from normal children below half a year of age. Dose-response curves with large volumes of sera from pituitary dwarfs and small volumes of sera from normal humans had the same slopes. Four mg of HGH prepared according to the method of Li & Papkoff (1956) resulted in a normal serum SF activity in each of the three dwarfs. A significant (P < 0.01) linear relationship was found between the concentration of SF activity of sera from these subjects and the logarithm of the dose of HGH given with dose levels of 1, 2 and 4 mg daily for three days. The decline of serum SF activity to the pre-treatment level following HGH in one dwarf suggested a half life not different from that indicated by others for growth hormone.

scholarly journals Case Report: Patient with Hepatitis C, p-ANCA, and Cryoglobulin Antibodies Presenting with Necrotizing Crescentic p-ANCA Glomerulonephritis

2018 ◽  
Vol 8 (2) ◽  
pp. 161-170
Author(s):  
Ramy M. Hanna ◽  
Naomi So ◽  
Marian Kaldas ◽  
Jean Hou ◽  
Farid Arman ◽  
...  
Keyword(s):  
Hepatitis C ◽  
Crescentic Glomerulonephritis ◽  
The United States ◽  
Cross Reactivity ◽  
Normal Serum ◽  
Hcv Infection ◽  
Low Grade ◽  
Glomerular Injury ◽  
Immune Assays

Hepatitis C (HCV) infection has a prevalence of 3 million infected individuals in the United States, according to recent Center for Disease Control reports, and can have various renal manifestations. Cryoglobulins, antibodies that precipitate at colder temperatures in vitro, are a relatively common cause of renal disease in HCV infection. The cryoglobulin proteins can form occlusive aggregates in small glomerular capillary lumina or deposit in other areas of the glomerulus, resulting in hypocomplementemia, proteinuria, hematuria, and renal injury. The typical biopsy pattern is that of membranoproliferative glomerulonephritis (MPGN). There are, however, other HCV-related patterns of glomerular injury. Anti-neutrophil cytoplasmic antibodies (ANCA) are known to exist in HCV-infected patients. In many reported cases, ANCA serologic testing may appear positive due to cross-reactivity of the immune assays; however, the biopsy findings do not support ANCA-associated crescentic glomerulonephritis (GN)/vasculitis as the primary cause of glomerular injury. There are rare reports of microscopic polyangiitis (MPA) p-ANCA vasculitis, in patients with HCV infection. In comparison with the MPGN pattern of cryoglobulinemic glomerular injury, biopsies from these HCV-infected patients with concomitant MPA revealed a crescentic GN, associated with normal serum complement levels. We present a case of HCV-associated glomerular disease with the surprising biopsy finding of necrotizing and crescentic p-ANCA GN, with a background, low-grade mesangial immune complex GN. Thus, p-ANCA disease should also be considered in HCV-infected patients, in addition to the more typical lesions of MPGN or cryoglobulinemic GN.

scholarly journals Multiplexed Detection of Sepsis Markers in Whole Blood using Nanocomposite Coated Electrochemical Sensors

2020 ◽  
Author(s):  
Uroš Zupančič ◽  
Pawan Jolly ◽  
Pedro Estrela ◽  
Despina Moschou ◽  
Donald E. Ingber
Keyword(s):  
Electrochemical Detection ◽  
Whole Blood ◽  
Electrochemical Sensors ◽  
Point Of Care ◽  
Sample Volume ◽  
Nanocomposite Coating ◽  
Cross Reactivity ◽  
Detection Methods ◽  
Clinical Samples ◽  
Undiluted Serum

ABSTRACTSepsis is a leading cause of mortality worldwide that is difficult to diagnose and manage because this requires simultaneous analysis of multiple biomarkers. Electrochemical detection methods could potentially provide a way to accurately quantify multiple sepsis biomarkers in a multiplexed manner as they have very low limits of detection and require minimal sensor instrumentation; however, affinity-based electrochemical sensors are usually hampered by biological fouling. Here we describe development of an electrochemical detection platform that enables detection of multiple sepsis biomarkers simultaneously by incorporating a recently developed nanocomposite coating composed of crosslinked bovine serum albumin containing a network of reduced graphene oxide nanoparticles that prevents biofouling. Using nanocomposite coated planar gold electrodes, we constructed a procalcitonin sensor and demonstrated sensitive PCT detection in undiluted serum and clinical samples, as well as excellent correlation with a conventional ELISA (adjusted r2 = 0.95). Sensors for two additional sepsis biomarkers — C-reactive protein and pathogen-associated molecular patterns — were developed on the same multiplexed platform and tested in whole blood. Due to the excellent antifouling properties of the nanocomposite coating, all three sensors exhibited specific responses within the clinically significant range without any cross-reactivity in the same channel with low sample volume. This platform enables sensitive simultaneous electrochemical detection of multiple analytes in human whole blood, which can be expanded further to any target analyte with an appropriate antibody pair or capturing probe, and thus, may offer a potentially valuable tool for development of clinical point-of-care diagnostics.GRAPHICAL ABSTRACT

scholarly journals Peptide arrays incubated with three collections of human sera from patients infected with mosquito-borne viruses

F1000Research ◽  
2020 ◽  
Vol 8 ◽  
pp. 1875
Author(s):  
Maria del Pilar Martinez Viedma ◽  
Nurgun Kose ◽  
Leda Parham ◽  
Angel Balmaseda ◽  
Guillermina Kuan ◽  
...  
Keyword(s):  
Vaccine Development ◽  
Cell Epitope ◽  
Cross Reactivity ◽  
Human Pathogens ◽  
Peptide Arrays ◽  
Serological Tests ◽  
Array Data ◽  
Prevalence Studies ◽  
Diagnostic Potential ◽  
Human Sera

Background: Global outbreaks caused by emerging or re-emerging arthropod-borne viruses (arboviruses) are becoming increasingly more common. These pathogens include the mosquito-borne viruses belonging to the Flavivirus and Alphavirus genera. These viruses often cause non-specific or asymptomatic infection, which can confound viral prevalence studies. In addition, many acute phase diagnostic tests rely on the detection of viral components such as RNA or antigen. Standard serological tests are often not reliable for diagnosis after seroconversion and convalescence due to cross-reactivity among flaviviruses. Methods: In order to contribute to development efforts for mosquito-borne serodiagnostics, we incubated 137 human sera on individual custom peptide arrays that consisted of over 866 unique peptides in quadruplicate. Our bioinformatics workflow to analyze these data incorporated machine learning, statistics, and B-cell epitope prediction. Results: Here we report the results of our peptide array data analysis, which revealed sets of peptides that have diagnostic potential for detecting past exposure to a subset of the tested human pathogens including Zika virus. These peptides were then confirmed using the well-established ELISA method. Conclusions: These array data, and the resulting peptides can be useful in diverse efforts including the development of new pan-flavivirus antibodies, more accurate epitope mapping, and vaccine development against these viral pathogens.

Concentrations of 2-hydroxyoestrogens in human sera measured by a heterologous immunoassay with an 125I-labelled ligand

1982 ◽  
Vol 100 (1) ◽  
pp. 154-160 ◽  
Author(s):  
D. Berg ◽  
F. Thaler ◽  
E. Kuss
Keyword(s):  
Standard Deviation ◽  
Binding Sites ◽  
Luteal Phase ◽  
Healthy Subjects ◽  
Cross Reactivity ◽  
Follicular Phase ◽  
Underlying Assumption ◽  
Human Sera ◽  
Tube Accuracy ◽  
Serum Components

Abstract. A heterologous immunoassay for 2-hydroxyoestrogens1 has been established in which antibodies raised against 2-hydroxyoestradiol-17-succinyl-BSA serve as binding protein and 2-hydroxyoestrone-17-cmo-[125I]iodohistamine as radioligand. Lipophilic serum components competing for binding sites in this system were defined as 'total 2-hydroxyoestrogens'. The underlying assumption of specificity was supported by the pattern of cross-reactivity evaluated with structural related steroids and o-diphenols and by the fact, that an additional chromatography of the serum extracts preceding the competing reaction had little if any effect. Sensitivity: 2.8 ± 1 pg/tube; accuracy: Y = 0.91x + 2.2; r = 0.989; precision: 5.8% intra-assay; 6.5% inter-assay. The following concentrations ( ± standard deviation) were found in the sera of healthy subjects. Young men: 29 ± 5 pg/ml (n = 11); women follicular phase: 32 ± 8 pg/ml (n = 25); luteal phase: 53 ± 13 pg/ml (n = 23); postmenopausal women: 13 ± 4 pg/ml (n = 10); pregnant women 11th–20th week: 70 ± 16 mg/ml (n = 64); 36th–40th week: 240 ± 23 pg/ml (n = 40); newborn cord blood: 604 ± 43 pg/ml (n = 48).

scholarly journals Antibodies in human sera to oncorna virus-like proteins from normal or leukemia marrow cell cultures.

1976 ◽  
Vol 144 (5) ◽  
pp. 1243-1253 ◽  
Author(s):  
S Louie ◽  
J E Curtis ◽  
J E Till ◽  
E A McCulloch
Keyword(s):  
Lupus Erythematosus ◽  
Competitive Inhibition ◽  
Marrow Cell ◽  
Leukemia Virus ◽  
Polyacrylamide Gel Electrophoresis ◽  
Cross Reactivity ◽  
Antibody Activity ◽  
Human Sera ◽  
Blood Specimens ◽  
Radioimmunoprecipitation Assay

Some human marrows in culture release particles with oncornavirus-like properties. This study was designed to examine the immunological properties of similar particles in human marrow culture supernates. Leukemic and nonleukemic marrows were cultured for 5-7 days in the presence of [14C]uridine and [3H]leucine or [3H]glucosamine. Labeled supernatant components banding in sucrose gradient densities of 1.20-1.24 g/ml were used as antigen in a double antibody immunoprecipitation assay. The assay was validated by end point titrations and competition with unlabeled antigen; purified myeloma proteins were used as negative controls. Cross-reactivity with mammalian oncornaviruses, as judged by competitive inhibition of precipitation by these viruses, was slight and at the border of the sensitivity of the method. Precipitated antigens analyzed by SDS polyacrylamide gel electrophoresis contained three distinct polypeptides of about 70,000, 45,000 and 30,000 mol wt; these comigrated with the gp 70, pg 45, and p 30 of a murine leukemia virus. Similar polypeptides were obtained from both leukemic and nonleukemic marrow culture supernates. As determined by the radioimmunoprecipitation assay, 32 of 45 leukemic sera (71%), 36 of 45 normal sera (80%), 15 of 19 sera from family contacts of leukemic patients (79%), 14 of 21 cord blood specimens (67%), and 21 of 23 sera (91%) from patients with systemic lupus erythematosus had detectable antibody activity.

Measurement of serum bone gla-protein (BGP) in humans with an ovine BGP-based radioimmunoassay

1990 ◽  
Vol 36 (9) ◽  
pp. 1620-1624 ◽  
Author(s):  
P Pastoureau ◽  
P D Delmas
Keyword(s):  
Amino Acids ◽  
Primary Hyperparathyroidism ◽  
Renal Osteodystrophy ◽  
Clinical Investigation ◽  
Gel Filtration ◽  
Normal Subjects ◽  
Conformational Epitope ◽  
Cross Reactivity ◽  
Bone Gla Protein ◽  
Human Sera

Abstract Most RIAs of serum bone gla-protein (BGP; also called osteocalcin) used for clinical investigation are based on bovine BGP for standard, tracer, and immunogen because of the homology between bovine and human BGP. However, ovine BGP differs from human BGP by only five amino acids, being identical from residues 11 to 49, as compared with homology at residues 20-49 between bovine and human BGP. In screening various anti-ovine BGP polyclonal anti-sera we selected one (R310) that exhibits apparently complete cross-reactivity with human BGP, as assessed by dilutions of 13 human sera from normal subjects and from patients with bone disease. This RIA gave a 42% binding at a 10,000-fold final dilution, with intra- and interassay variations less than 7% and 11%, respectively. Gel-filtration chromatography of human serum showed a single immunoreactive peak. Synthetic fragments of human BGP 1-10, 7-19, 25-37, and 37-49 were not recognized by R310, suggesting that either a mid-molecule region or a conformational epitope was its target. Using this RIA, we determined that serum BGP increased with age in women (P less than 0.02), by a mean of 90% from ages 30 to 70 years. Serum BGP was also increased in patients with primary hyperparathyroidism, renal osteodystrophy, and Paget's disease. In contrast with the "normal" concentrations of BGP detected with an anti-bovine BGP antiserum (R102), serum BGP was increased in patients with postmenopausal osteoporosis as measured with the R310 ovine assay, suggesting a greater sensitivity for the latter assay.

Identification of a HSP14‐3‐3 in Setaria cervi and its cross‐reactivity with W bancrofti ‐infected human sera

2020 ◽  
Vol 42 (11) ◽  
Author(s):  
Faiyaz Ahmad ◽  
Ranjeet Kumar ◽  
Sarika Gupta ◽  
Sushma Rathaur
Keyword(s):  
Cross Reactivity ◽  
Setaria Cervi ◽  
Human Sera

scholarly journals Benign Prostate-specific Antigen (BPSA) in Serum Is Increased in Benign Prostate Disease

2003 ◽  
Vol 49 (2) ◽  
pp. 253-259 ◽  
Author(s):  
Harry J Linton ◽  
Leonard S Marks ◽  
Lisa S Millar ◽  
Christine L Knott ◽  
Harry G Rittenhouse ◽  
...  
Keyword(s):  
Prostate Specific Antigen ◽  
Limit Of Detection ◽  
Specific Antigen ◽  
Clinical Information ◽  
High Specificity ◽  
Wide Distribution ◽  
Cross Reactivity ◽  
Free Psa ◽  
Control Serum ◽  
Benign Prostate

Abstract Background: BPSA is a “benign” form of free prostate-specific antigen (PSA) that is increased in prostate transition zone tissues of men with pathologic benign prostatic hyperplasia (BPH). We developed an immunoassay to determine the concentration of BPSA in the serum of men with BPH. Methods: The BPSA antigen was purified by HPLC, and murine monoclonal antibodies were prepared by standard methods. A fluorogenic ELISA was developed with high specificity for BPSA and no cross-reactivity with other forms of PSA. Results: The BPSA immunoassay had a lower limit of detection of 6 ng/L and a cross-reactivity of &lt;1% with all other clipped and nonclipped forms of PSA. The BPSA antibody was specific for the internal Lys182 cleavage site that characterizes BPSA. Biopsy-negative men with a median total PSA of 4.8 μg/L had a median of 0.22 μg/L BPSA, representing 25% of the free PSA in serum. BPSA ranged from 0% to 60% of the free PSA in serum. BPSA in a cohort of cancer serum also comprised 25% of the free PSA. Control serum from women or men without increased PSA had nondetectable BPSA. Conclusions: BPSA is a significant percentage of the free PSA in BPH serum but not in control serum. The presence of prostate cancer does not alter the relative proportions of BPSA in sera with &lt;10 μg/L PSA. BPSA has a wide distribution of concentrations in the serum and may provide clinical information for the study of men with BPH.

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