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Hypersensitivity
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
Serum concentrations of complement components can be measured by the radial immunodiffusion test. Specific antisera against individual components are incorporated into agar, and the patient's serum is placed in wells in the agar. Raised concentrations of components of complement are frequently found in acute inflammation. A reduction in concentration of complement can be due to: Primary genetically determined immunodeficiency disorders.Secondary deficiencies caused by complement consuming antibody–antigen interactions or associated with liver or renal disease. Complement activation in allergic reactions is usually associated with decreases in C3 or C4 concentrations in serum or increases in concentrations of products of complement activation (e.g. C3a, C4a and C5a).
Inherited Differences in Alpha1-Antitrypsin
Published in Stephen D. Litwin, Genetic Determinants of Pulmonary Disease, 2020
Precise determinations of individual inhibitors can be made by immunologic techniques using specific antisera. Radial immunodiffusion [9,34-36] has proved particularly useful. By this method the normal concentration of alpha1-antitrypsin is 212 ± 32 mg/dl. The accuracy of this measurement largely depends on the purity of the preparation used as the standard. The presence of contaminating proteins in the standard would result in erroneously high estimates of alphai-antitrypsin. Some laboratories have therefore adopted the practice of expressing their results as percent of a pool of normal sera. Commonly used pools are available from Dr. Fagerhol* and from Dr. Pierce.†
Immunological Approaches
Published in Adorjan Aszalos, Modern Analysis of Antibiotics, 2020
Deborah E. Dixon, Susan J. Steiner, Stanley E. Katz
The diffusion procedure, the basis of the classic microbiological procedures that have been used to measure antibiotics, can be used to assay antibiotics using the antigen-antibody reaction. Radial immunodiffusion is quite similar to the agar well diffusion procedure. Agar containing antibody is poured onto a suitable glass surface, and wells are cut. The solution containing the antigen (the antibiotic) is pipetted into the well. After a period of diffusion, at a constant temperature, a ring of precipitin forms. The diameter of the ring is proportional to the concentration of the antigen. As in the classic microbial diffusion assay, a standard curve is prepared and the concentration of the unknown is determined from the curve [8].
Quantification methods for viruses and virus-like particles applied in biopharmaceutical production processes
Published in Expert Review of Vaccines, 2022
Keven Lothert, Friederike Eilts, Michael W. Wolff
Alternative approaches for antigen detection and quantification are the single radial immunodiffusion assay (SRID) [61] and the hemagglutination assay [62,63], both described already in the 1950s and 1960s, and still being routinely applied for the indirect quantification of viruses. To date, the SRID is used for the regulatory release of human influenza vaccines [64–66]. In both assays, the surface protein hemagglutinin, and thereby the amount of virus particles, can be estimated for viruses carrying that specific antigen, such as the influenza or the measles viruses. Thus, many reports on these two assays focus on influenza vaccine production and processing [67–72]. However, these assays are also used for a series of other viruses. Recently, Cheng et al. described the quantification of the porcine circovirus type 2 by a hemagglutination assay for virus concentrations of down to 104 TCID50 per ml [73].
Prognostic value of cryoglobulins, protein electrophoresis, and serum immunoglobulins for lymphoma development in patients with Sjögren’s syndrome. A retrospective cohort study
Published in Acta Clinica Belgica, 2018
Jesse Kimman, Xavier Bossuyt, Daniel Blockmans
For the detection and quantification of cryoglobulins, blood samples were taken by venipuncture in pre-heated (to 37 °C) 10 mL serum tubes. Until the serum was separated, all tubes were maintained at 37 °C. The serum samples were transported at ambient temperature, and reheated to 37 °C before further processing [29]. Aliquots of serum were allowed to precipitate at 4 °C for 7 days. These samples were washed three times with phosphate-buffered saline (PBS) at 4 °C and dissolved in PBS at 37 °C. This material was subjected to electrophoresis and identification of monoclonal proteins. Individual immunoglobulin levels (IgA, IgG, and IgM) were quantified with NOR-Partigen® reagents on radial immunodiffusion until 2004, Turbiquant® reagents on Turbitimer (Dade-Behring) until 2012, and thereafter on Immage (Beckman Coulter) [29].
Establishment of anti-C1q monoclonal antibodies to measure serum C1q levels discriminating disease severity subsets of rheumatoid arthritis within 5 years of onset
Published in Modern Rheumatology, 2020
Chikako Yukioka, Kosuke Ebina, Yasunori Shimaoka, Masao Yukioka, Hideki Yoshikawa, Ken Nakata, Takahiro Ochi
We previously developed RA severity classification evaluated by the number of joints with erosions among 68 joints of whole body using plain radiographs (XPs) [2]. Joint erosion was defined as changes equal or more than stage II according to the criteria of Steinbocker et al. [6], and patients with more than 10 years of RA disease duration were classified as previously described [1,7]. Then, we tried to find out independent predictive markers discriminating these disease subsets of RA [2]. Considering the pathophysiology of RA, we were interested in complement system which plays important roles in autoimmune diseases. We found that serum C1q levels of RA patients were significantly higher compared to healthy controls [8], and also it remained constant irrespective of disease activity [2]. Moreover, serum C1q levels of patients in the MES/MUD groups remained constantly higher for the first 5 years of RA than those in the LES groups. From these results, serum C1q levels in the first 5 years of RA were considered to be a good candidate for prospective prognostic marker of joint destruction, although had to overcome some problems as follows. In our previous studies, serum C1q levels were evaluated by single radial immunodiffusion using the same lot of rabbit polyclonal antibodies to C1q prepared from the pooled human serum [9]. After studying other RA cases using other lots of polyclonal antibodies, we realized the variation of serum C1q levels depending on the difference of these lots. In recent years, we established 4 monoclonal antibodies (mAbs) to human C1q, which could be used in enzyme-linked immunosorbent assays (ELISA), and re-measured the serum C1q levels of stored serum obtained from RA patients in previous study [1]. The aim of this study was to investigate whether the serum C1q levels measured by newly developed mAbs could be prospective prognostic markers discriminating disease severity subsets of RA within 5 years of onset.