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Animal Source Foods
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Protein is distributed in both egg white and yolk. Egg white is mainly composed of protein (11%), with ovalbumin being the most abundant (54%), followed by ovotransferrin (12%), ovomucoid (11%), lysozyme (3.5%), and ovomucin (3.5%) (111–115). Other minor proteins such as ovoglycoprotein, ovoflavoprotein, ovomacroglobulin, avidin, cystatin, and ovoinhibitor have also been identified (112, 114–115). The main components of the yolk are lipids (31–35%), although it also has 15–17% of proteins including lipovitellins (36%), livetins (38%), phosvitin (8%), and low-density lipoproteins (17%) (115). Egg yolk is covered with the vitelline membrane which separates it from the egg white. It is also a good source of proteins, being composed mostly of protein fibers (115).
Food allergens
Published in Richard F. Lockey, Dennis K. Ledford, Allergens and Allergen Immunotherapy, 2020
Several studies have identified the major chicken egg allergens [27,28]. Ovomucoid (Gal d 1), a glycoprotein with a molecular weight of 28 kDa and an acidic isoelectric point, is the major egg allergen. In a study of 18 children with egg allergy, ovomucoid was a more potent allergen than purified ovalbumin as determined by skin prick and in vitro specific IgE tests [29]. While previous studies indicated that ovalbumin was the major egg allergen, this work demonstrated ovomucoid contamination of the ovalbumin accounted for the discrepancy. Ovalbumin (Gal d 2) is a monomeric phosphoglycoprotein with a molecular weight of 43–45 kDa and an acidic isoelectric point. Purified ovalbumin has three primary variants, A1, A2, and A3. It is difficult to determine the exact role of Gal d 2 because of ovomucoid contamination of ovalbumin [29]. Ovotransferrin (Gal d 3), or conalbumin, has a molecular weight of 78 kDa, an acidic isoelectric point, and antimicrobial activity and iron-binding properties. Lysozyme (Gal d 4) is a lower molecular weight allergen (14.3 kDa) that in some studies appears to be a major allergen but in other studies is a minor allergen. Other minor allergens in eggs include serum albumin (Gal d 5), YGP42 (Gal d 6), myosin light chain 1f (Gal d 7), α-parvalbumin (Gal d 8), β-enolase (Gal d 9), and aldolase (Gal d 10). The carbohydrate portion of the glycoproteins in eggs, particularly in ovomucoid, does not play a primary role in specific IgE binding.
Immunohistochem1Cal Studies with Antibodies to the Chicken Oviduct Progesterone Receptor
Published in Louis P. Pertschuk, Sin Hang Lee, Localization of Putative Steroid Receptors, 2019
Jean-Marie Gase, Etienne-Emile Baulieu
Different preparation procedures have yielded several forms and components of PR. Nontransformed 8S-PR forms have been purified, using stabilization by molybdate ions.2,11 They contain two distinct progesterone-binding subunits, A and B (Mr = 79K and 110K, respectively),3,12 and a third protein component of Mr ~ 90K which does not bind progesterone.4 Three antibodies were used in this study. Their specificity was tested by density gradient centrifugation technique and by immunoblots after SDS-PAGE. A goat polyclonal antibody (IgG-G3)6 reacts with the subunits A, B, and 90K. as well as with the 8S-PR.2 The rat monoclonal antibody BF47 specifically reacts with the 90K protein. IgG-RB5,8 is a rabbit polyclonal antibody obtained after immunization with purified B subunit. It interacts with both the A and B subunits but not with the 90K. All preparations used were IgG-G fractions from immune sera or culture medium. The three antibodies were used alone, and also in conjunction with purified proteins utilized in presaturation experiments in order to control the specificity of the immunodetection of receptor. Thus, the 8S-PR, B subunit and the 90K protein were purified and systematically used. Other proteins also occasionally used in presaturation control experiments were the oviduct proteins ovalbumin and conalbumin, or serum proteins.
Absence of active systemic anaphylaxis in guinea pigs upon intramuscular injection of inactivated SARS-CoV-2 vaccine (Vero cells)
Published in Immunopharmacology and Immunotoxicology, 2022
Zhangqiong Huang, Yun Li, Hongkun Yi, Zhengcun Wu, Cong Li, Tingfu Du, Jinling Yang, Yixuan Wang, Qinfang Jiang, Shengtao Fan, Yun Liao, Ying Zhang, Guorun Jiang, Kaili Ma, Qihan Li
In summary, in accordance with the guidelines issued by CDE and CFDA [3,18], this study compared the occurrence of ASA among guinea pigs injected with normal saline (negative control group), inactivated SARS-CoV-2 vaccine (inactivated SARS-CoV-2 vaccine group), and 10% ovalbumin (100 mg/kg; positive control group). No abnormal symptoms occurred during the trial. After the intravenous challenge, the negative control and the inactivated SARS-CoV-2 vaccine groups did not show any allergic reactions. In contrast, the incidence of allergic reactions in the ovalbumin-positive control group was 100%. In the positive control group, there was no significant difference in the severity of allergic symptoms between the individual animals (Table 4). Allergic reactions were strongly positive except for one animal (M05), which confirms the reliability of the experimental setting.
Effect of H4R Antagonist N-(2-Aminoethyl)-5-Chloro-1H-Indole-2-Carboxamide (Compound A) in a Mouse Model of Allergic Asthma
Published in Immunological Investigations, 2021
Gomathi Nagarajan, Elden Berla Thangam
Animals were divided into six groups [control, OVA, Compound A (10, 20, 30 mg/kg) + OVA and JNJ7777120 (10 mg/kg) + OVA] each group consisting of 6 animals. Ovalbumin was used to induce airway inflammation for different groups, using the method described by Ji-Eun Yuk et al. (24). Briefly, 20 μg chicken OVA along with 2 mg of aluminum hydroxide in 200 μL PBS buffer at the pH 7.4 was used to immunize mice via intraperitoneal (i.p.) injection, on days 0, and booster injections on day 7 and 14. After initial sensitization, on days 28, 29, and 30 the animals were exposed 20 min. to a 1% (w/v) of OVA solution prepared in PBS. The animals in treatment group were pre-treated with compound A or JNJ7777120 orally 20 min before OVA treatment. To characterize the inhibitory effects of compound A, animals were sacrificed on day 32 after the challenge (Scheme 1). In the present work, JNJ7777120 a standard H4R antagonist was used as a standard H4R antagonist.
Highly sensitive detection of antibody nonspecific interactions using flow cytometry
Published in mAbs, 2021
Emily K. Makowski, Lina Wu, Alec A. Desai, Peter M. Tessier
It is also notable that ovalbumin proved to be the most useful polyspecificity reagent in our study and even more useful than more complex reagents, including the original PSR reagent composed of soluble membrane proteins. While it is unclear why ovalbumin performs best, it may be due to its unique combination of properties. These properties include the fact that ovalbumin is an acidic protein (pI of ~4.5) and negatively charged at physiological conditions, as discussed above. Moreover, ovalbumin (like other albumins) presents hydrophobic patches on its surface that may also be important for detecting nonspecific interactions. Finally, ovalbumin has several post-translational modifications, including N-acetylation, phosphorylation, and N-linked glycosylation,36 and these diverse chemical moieties may also enable detection of diverse types of nonspecific interactions that have previously been detected using more complex reagents. Regardless, the simple and well-defined nature of ovalbumin is much more attractive and practical than complex reagents such as soluble membrane proteins isolated from CHO cells, and much less expensive and widely available at high purity than chaperones such as Hsp90. This discovery combined with our sensitive flow cytometry assay is expected to accelerate the evaluation of antibody polyspecificity during the discovery and engineering of antibodies for diverse biomedical and therapeutic applications.