Immunochemical Characteristics Research Articles

Immunochemical Characterization of Salix alba (S. alba) Pollen Allergens and Evaluation of the Cross-Reactivity Pattern with Common Allergenic Pollen Grains

BackgroundPollens, particularly tree and plant pollens, are one of the major causes of allergic respiratory diseases worldwide. Allergy to pollens of different species of Salix trees has been reported in various regions of the world. The most common type of Salix tree in Iran is white willow (Salix alba). ObjectivesThis study aimed to identify and determine the immunochemical characteristics of allergenic proteins in S. alba tree pollen extract using SDS-PAGE and IgE- immunoblotting methods. Moreover, the cross-reaction pattern of the specific IgE antibody of S. alba tree pollen proteins with pollen allergens of common allergenic trees, i.e., Populus nigra (P. nigra), Cupressus sempervirens (C. sempervirens), Pinus brutia (P. brutia) and Platanus orientalis (P. orientalis) in the region was investigated. MethodsThe reaction of allergenic proteins in S. alba pollen extract with specific IgE antibodies in patients' sera was investigated using SDS-PAGE and IgE-immunoblotting methods. The cross-reaction of specific IgE antibodies of the proteins present in S. alba pollen extract with pollen allergens of common allergenic trees in the region was investigated using ELISA and immunoblotting inhibition methods. In silico methods such as phylogenetic tree drawing and alignment of amino acid sequences were used to examine the evolutionary relationship and homology structure of common allergenic proteins (Panallergens) responsible for cross reactions. ResultsMore than 11 protein bands binding to specific IgE antibodies in patients' sera with a molecular weight between 13 and 95 kDa were identified in the S. alba tree pollen extract. ELISA and immunoblotting inhibition results showed that P. nigra extract could inhibit the binding of IgE antibodies to S. alba pollen extract proteins to a greater extent than C. sempervirens, P. brutia, and P. orientalis tree extracts. In silico methods investigated the results of ELISA and immunoblotting inhibition methods. Moreover, a high structural homology and evolutionary relationship were observed between S. alba and P. nigra tree pollen panallergens. ConclusionIn this study, it was found that more than 80 % of the sensitive patients who were examined had specific IgE antibodies reacting with the approximately a 15 kDa-protein present in the S. alba pollen extract. Furthermore, the specific IgE-binding proteins found in the pollens of S. alba and P. nigra trees had relative structural homology, and it is likely that if recombinant forms are produced, they can be used for diagnostic and therapeutic purposes for both of the trees.

Exaggerated risk perception of asbestos-related diseases: commentary

Health risks from asbestos have been evaluated on the basis of professional histories from remote past, when exposures at workplaces were greater than today. The linear no-threshold model has been applied, although its relevance has not been demonstrated. Fibers are often found in the lungs and pleura at post mortem examinations. The fnding of fbers does not prove that a disease was caused by asbestos. It can be reasonably assumed that targeted search for mesothelioma and other asbestos-related diseases in exposed people resulted in increased detection rate. Histological and immunochemical characteristics of malignant mesothelioma partly overlap with other cancers, which may contribute to overdiagnosis in exposed populations. Amphibole asbestos is more toxic than chrysotile but there are discrepancies between experimental and epidemiological data. The promising way to obtain reliable information is lifelong animal experiments. Asbestos bans applied in some countries are excessive and should be reconsidered on the basis of independent research. It can be reasonably assumed that non-use of asbestos-containing brakes, freproofng, and insulation increases the harm from fres, armed conflicts and trafc accidents.

Exclusive Human Milk Diet for Extremely Premature Infants: A Novel Fortification Strategy That Enhances the Bioactive Properties of Fresh, Frozen, and Pasteurized Milk Specimens

Background: Human milk (HM) fortification has been recommended for the nutritional optimization of very low-birthweight infants. This study analyzed the bioactive components of HM and evaluated fortification choices that could accentuate or attenuate the concentration of such components, with special reference to human milk-derived fortifier (HMDF) offered to extremely premature infants as an exclusive human milk diet. Materials and Methods: An observational feasibility study analyzed the biochemical and immunochemical characteristics of mothers' own milk (MOM), both fresh and frozen, and pasteurized banked donor human milk (DHM), each supplemented with either HMDF or cow's milk-derived fortifier (CMDF). Gestation-specific specimens were analyzed for macronutrients, pH, total solids, antioxidant activity (AA), α-lactalbumin, lactoferrin, lysozyme, and α- and β-caseins. Data were analyzed for variance applying general linear model and Tukey's test for pairwise comparison. Results: DHM exhibited significantly lower (p < 0.05) lactoferrin and α-lactalbumin concentrations than fresh and frozen MOM. HMDF reinstated lactoferrin and α-lactalbumin and exhibited higher protein, fat, and total solids (p < 0.05) in comparison to unfortified and CMDF-supplemented specimens. HMDF had the highest (p < 0.05) AA, suggesting the potential capability of HMDF to enhance oxidative scavenging. Conclusion: DHM, compared with MOM, has reduced bioactive properties, and CMDF conferred the least additional bioactive components. Reinstatement and further enhancement of bioactivity, which has been attenuated through pasteurization of DHM, is demonstrated through HMDF supplementation. Freshly expressed MOM fortified with HMDF and given early, enterally, and exclusively (3E) appears an optimal nutritional choice for extremely premature infants.

Epidemiology of monoclonal gammopathy in Morocco – A hospital‐based study

Monoclonal gammopathies are a group of disorders associated with clonal proliferation of plasma cells that produces a monoclonal protein. The main objective of this study was to describe the epidemiological and immunochemical characteristics of monoclonal gammopathies diagnosed during 19 years in a Moroccan teaching hospital. This retrospective study enrolled 443 Moroccan patients with monoclonal gammopathy, patients meeting the inclusion and exclusion criteria in at the biochemistry department of Military Hospital in Rabat, the capital of Morocco, from January 2000 to August 2019. Of the 443 enrolled patients, 320 (72.23%) were men and 123 (27.77%) were women. All patients were of Caucasian origin, from 12 Moroccan regions. The patient's samples were collected and subjected to serum protein electrophoresis and serum immunofixation electrophoresis to further characterize the monoclonal protein. The mean ± SD age of the 443 participants was 62.24 ± 13.14 years. Reasons for being admitted to the hospital were as follows, bone pain (41.60%), renal failure (19.08%), alteration of the general condition (12.21%), and anemia (10.69). Plasma cell proliferative disorders in our study were as follows, multiple myeloma (MM) (45.65%), Monoclonal gammopathies of undetermined significance (MGUS) (39.05%), Waldenstrom's macroglobulinemia (5.58%), Lymphoma (2.27% + 1.2%), Chronic Lymphocytic Leukemia (2.48%), Plasma cell leukemia (1.86%), Plasmacytoma (0.62%), POEMS syndrome (0.41%), and Amyloidosis (0.84%). The most frequent isotypes in MM were the IgGκ (62) 36.5%, IgGλ (52) 30.6%, IgAκ (27) 15.9%, and the IgAλ (19) 11.2%. It is also worth noting that Free light chain MM represents 20% of all cases of MM. We found that monoclonal gammopathies are age-related and affects men more than women, also the results of this study point to the delayed diagnosis of monoclonal gammopathies, since most of our patients were diagnosed at the MM stage. The most frequent isotypes were the IgGκ and IgGλ in MM and MGUS, in Waldenström macroglobulinemia were IgMκ and IgMλ and the oligoclonal profile represented only 3.70%.

Asbestos-related Cancer: Exaggerated Risk Perception

Health risks from exposure to asbestos fibers have been evaluated based on professional histories, when fiber concentrations at workplaces were greater than today. A linear no-threshold model was used for risk estimation, although its relevance has not been proven. Asbestos fibers are often detected in lungs and pleura during autopsy, but finding evidence of fibers does not prove that a disease has been caused by asbestos. Thus, targeted detection of mesothelioma and other conditions associated with asbestos exposures has resulted in an increase in the reported incidence of mesothelioma among high-risk groups. Histological and immunochemical characteristics of malignant mesothelioma partially overlap with other cancers, which may also contribute to the overdiagnosis in exposed populations. Differences in carcinogenicity of various asbestos types are discussed here. Prohibitions of asbestos in some developed countries must be reconsidered on the basis of independent research. Life-long bioassays are the most promising way to obtain reliable information regarding asbestos-related malignancy. It should be stressed that non-use of asbestos contributes to an increase of harm from fires, armed conflicts, and traffic accidents.

Endoscopic Ultrasound-Guided Fine Needle Aspiration of Solid Pseudopapillary Neoplasm of the Pancreas in a Male Patient: A Rare Report

Abstract Introduction/Objective Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare pancreatic tumor with low malignant potential composed of poorly cohesive epithelial cells forming solid and pseudopapillary structures. It develops almost exclusively (90%) in young females (mean age: 28 years, range: 7-79 years), while it rarely develops in men (mean age: 35 years, range: 25-72 years). Methods/Case Report Herein we report an unusual presentation of SPN in a 59-year-old male who presented with severe nausea, vomiting, right upper quadrant pain, and weight loss. Computed tomography imaging revealed a large pancreatic head/uncinate process mass. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsies showed abundant monomorphic cuboidal tumor cells arranged in loosely cohesive groups and singly dispersed cells. A few tumor cells are arranged in multiple layers around vascular structures expanded by metachromatic hyaline material. The tumor cells have thin cytoplasm, indistinct cell borders, round to oval nuclei, finely dispersed chromatin, and indistinct nucleoli. No mitosis, tumor necrosis, or other high-grade features are identified. Immunohistochemical stains are performed on cell block material and the tumor cells are positive for beta-catenin (nuclear), cyclin D1, vimentin, CD10, synaptophysin, and CD56, and negative for DOG-1, tryptase, and AE1/AE3. Ki-67 proliferative index is less than 2% in tumor cells. The cytomorphologic features and immunoreactivity are diagnostic of solid pseudopapillary neoplasm. We diagnosed SPN preoperatively by EUS-FNA using cytopathologic and immunochemical characteristics, which are very helpful to differentiate SPN from acinar cell carcinoma, neuroendocrine tumor, pancreatoblastoma, or other pancreatic tumors. Results (if a Case Study enter NA) NA Conclusion EUS-FNA can be used as a gold standard method to characterize and diagnose SPN preoperatively and help to guide clinical management.

Epithelioid Inflammatory Myofibroblastic Sarcoma Presenting as Gastrointestinal Bleed: Case Report and Literature Review

Myofibroblastic tumor is a mesenchymal neoplasm composed of myofibroblastic spindle cells with inflammatory infiltrate and considered to be of low-malignant potential tumor. Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a variant of myofibroblastic tumor with malignant characteristics; it mainly consists of round-to-epithelioid cells with positive nuclear membrane/perinuclear immunostaining for anaplastic lymphoma kinase (ALK) receptor tyrosine kinase. A gastric EIMS case in a 7-year-old boy is discussed. Our patient presented with severe anemia and melena. Magnetic resonance imaging of the abdomen and pelvis revealed a solid tumor (2.7 × 1.9 × 2.6 cm) at the posterior stomach wall. Upper gastrointestinal endoscopy revealed an irregular, protruding, highly vascular, approximately 2 cm mass close to the gastrooesophageal junction. Endoscopic biopsies were taken for histology; tumor cells were epithelioid with eccentric nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. Immunohistochemistry showed positive staining for desmin, smooth muscle actin, epithelial membrane antigen, cluster of differentiation CD30, and strongly positive staining for ALK. Fluorescence in situ hybridization analysis confirmed the presence of ALK rearrangements. A full-thickness surgical excision of the tumor with clear margins was performed. No adjunct treatment was administered and our patient has remained in full remission at 12 months following the surgery. To the best of our knowledge, this is the first pediatric case of gastric EIMS. Raised awareness and prompt recognition of special histological and immunochemical characteristics of EIMS can lead to accurate diagnosis and targeted therapy.

Immunochemical characteristics of Streptococcus pneumoniae type 3 capsular polysaccharide glycoconjugate constructs correlate with its immunogenicity in mice model

A panel of derivatives were prepared from Streptococcus pneumoniae polysaccharide type 3 (Ps3) modified with adipic acid dihydrazide (ADH). The degree of coupling between Ps3-adh derivatives and diphtheria (DTd) or tetanus (TTd) toxoids was varied by ADH linker loading. A series of Ps3 derivatives and the resultant glycoconjugates (GC) were tested for their immunochemical activity in an ELISA. Antigenic properties of components in GCs were estimated by interaction with serotype-specific and toxin-neutralizing antibodies to confirm the preservation of native protective epitopes both of Ps3 and DTd. After immunization of mice, a correlation was established between immunochemical activity and immunogenicity of these GCs. A correlation model developed for Ps3-DTd conjugates allowed to predict the immunogenicity of similar design Ps3-TTd conjugates based on ELISA testing data. The plausibility of this prediction was confirmed by the test immunization of mice with Ps3-TTds. The proposed immunochemical approach to the assessment and control of native structural and functional antigenic elements in GCs is important for the optimization of vaccine design and is an adequate alternative to extensive physicochemical characterization for assessing immunogenicity.

Toxicological, enzymatic, and immunochemical characterization of Bothrops asper (Serpentes: Viperidae) reference venom from Panama

ABSTRACT: Introduction: It is estimated that 2000 snakebites occur in Panama every year, 70% of which are inflicted by B. asper. Objective: To determine the biochemical and toxicologic effects and to assess the immunochemical characteristics of the reference B. asper venom experimentally used in this work. Methods: The venom was prepared as a homogeneous mixture of the venoms obtained from 78 adult specimens of this species collected in four geographic areas of Panama. Enzymatic and toxicologic activities were assayed following the specific methodologies of each experiment. SDS-PAGE (15% gel) was carried out under reducing conditions. Subsequently, Western blotting was performed. Results: It was found that this venom has lethal, hemorrhagic, myotoxic, edema-forming, coagulant, defibrinating, proteinase and phospholipase A2 activities. SDS-PAGE (15%) showed the presence in this venom of protein bands with molecular weights ranging from 8 to 70kDa, with the presence of predominant bands at ≈ 15kDa and ≈ 30 to 66kDa, which probably correspond to phospholipases A2 (the former) and metalloproteinases (the latter), respectively. Through immunoblotting, a high degree of recognition by various antivenoms was observed, mainly from Colombian and Costa Rican antivenoms. Conclusion: This B. asper reference venom will be highly useful for the preclinical evaluation of antivenoms.

Cryoglobulins: putative effectors of adaptive immune response.

Cryoglobulinaemia consists of circulating monoclonal and/or polyclonal immunoglobulins with rheumatoid factor (RF) activity that precipitate at temperatures <37°C. Cryoglobulinaemic syndrome, characterised by clinical signs of systemic vasculitis, is associated with chronic infection of hepatitis C virus (HCV) and might evolve in B-cell malignancies. In about one third of all HCV infection cases, serum autoantibodies are commonly found. This is probably due directly to the transformation of infected B cells but, also, indirectly, to the viral chronic stimulation of a pool of autoreactive B cells. The pattern of IgG subclasses seems to contribute to the worsening progression of HCV infection into lymphoproliferative and/or autoimmune diseases. Many evidences showed that B cells circulating in patients with HCV-associated mixed cryoglobulinaemia (MC) are profoundly abnormal; moreover, in most of cases, normal B cells are replaced by expanded clonal B cells characterized by the low expression of CD21. After viral eradication, these cells persist in circulation and their occurrence does not correlate with serum cryoglobulins nor with vasculitis response or relapse. It is probably due to the persistence of monoclonal B cells producing RF, that in course of MC can be reactivated by circulating immune complexes, highly produced during infections or tumours. Here, we aimed to review current literature focusing the pathogenesis of MC referring to specificity and immunochemical characteristics of the immunoglobulins involved in cryoprecipitation.

Cloning and Expression of 2S Albumin As a Major Allergen of Persian Walnut

Background: Food hypersensitivity to walnut usually results in mild symptoms; however, several cases of anaphylactic reactions to this product have been observed. This study aimed to determine the immunochemical characteristics of the Persian walnut and provide the recombinant form of its main allergen. Materials and Methods: The allergenic proteins of the Persian walnut were extracted by standard procedure. The IgE-binding profile was determined by common immunoassays, including ELISA and Western blotting. The characteristics of the main allergenic protein which showed a stronger and higher frequency of IgE-reactivity with the patient’s sera was identified by MALDI-TOF-TOF method. The conventional PCR was used for the amplification of the coding sequence of the target protein which was then inserted into pET-21b(+) vector and expressed in E. coli BL21. The recombinant allergen was purified by metal affinity chromatography and the ELISA and immunoblotting assays were used for the evaluation of the IgE-binding capacity of the recombinant protein.Results: All patients showed a considerable specific IgE-reactivity to total extract (OD 0.58±0.43 versus 0.047±0.026; P<0.05) in ELISA. Immunoblotting with crude extract indicated considerable IgE-reactivity of the patients’ sera with a 15-kDa allergen which was characterized as 2S albumin by mass spectrometry methods. The refolded walnut recombinant 2S albumin showed considerable IgE-reactivity in ELISA and western blotting with patients’ sera. Conclusion: We demonstrated that the refolding of walnut recombinant 2S albumin could result in the reconstruction of an IgE-reactive allergen with a rather similar immunoreactivity to its natural counterpart. The refolded recombinant protein could be a suitable candidate for diagnostic and therapeutic approaches.

Sensitive and selective quantification of mid-regional proadrenomedullin in human plasma using ultra-performance liquid chromatography coupled with tandem mass spectrometry

Mid-regional pro-adrenomedullin (MR-proADM) is suggested to be a prognostic indicator for various diseases. Plasma MR-proADM concentration is commonly measured using immunoassays based on its immunochemical characteristics. However, some immunological interactions affect the measured concentration. We developed and validated a sensitive and selective method for measuring plasma MR-proADM concentration using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) and evaluated its clinical applicability. Plasma samples were prepared by protein precipitation and solid-phase extraction. Samples obtained from healthy volunteers (n = 38), patients with chronic kidney disease (CKD) stages 3 and 4–5 (non-dialysis; n = 20 and 17, respectively), and CKD stage 5D (dialysis; n = 34) were analyzed. Within-batch and batch-to-batch accuracy of the UPLC-MS/MS assay for quality control samples ranged from −0.69 % to 8.05 % and from 1.72 % to 5.76 %, respectively. The lower limit of quantification was 0.4 ng mL−1. The MR-proADM concentration determined using the UPLC-MS/MS assay correlated strongly with that determined using the immunoassay (Pearson’s product-moment correlation coefficient [r] = 0.7875, p < 0.001). Median (range) plasma MR-proADM concentrations of healthy volunteers, patients with CKD stages 3 and 4–5, and patients with CKD stage 5D were 0.67 (0.43–1.27), 1.89 (0.65–6.68), 3.86 (1.60–8.75) and 3.97 (0.66–9.20) ng mL−1, respectively, and a significant difference among four groups was confirmed. We established a sensitive and selective method for determining plasma MR-proADM concentration using UPLC-MS/MS. Our novel UPLC-MS/MS assay for determining plasma MR-proADM concentration can be used in the clinical setting and may have better selectivity than the immunoassay method.

Enzymatic hydrolysates of whey protein and chicken egg ppotein: production, physical-chemical and immunochemical characteristics

Whey protein concentrate (WPC) and chicken egg protein (CEP) and enzymes such as pancreatin and alkalase have been used. Proteolysis of proteins was carried out in an FA-10 fermenter for 3 hours at an enzyme : substrate ratio of 1:50 in dry matter, at optimal pH and temperature for pancreatin and alkalase. Enzymes were inactivated at +75 °C and fermentolizate was ultrafiltered. The solutions were concentrated by reverse osmosis and freeze-dried. The molecular weight distribution of the peptide fractions was evaluated by HPLC. Residual antigenicity was determined by the method of indirect enzyme-linked immunosorbent assay and expressed as the fold of antigenicity reduction relative to the original protein. During WPC proteolysis with pancreatin the hydrolyzate was obtained with a fold reduction of antigenicity of 2.3×103 relative to the initial WPC. A decrease in antigenicity of 4.7×104 times was achieved with proteolysis of WPC by alkalase. The combination of WPC fermentolysis with pancreatin or alkalase followed by ultrafiltration reduced the content of high molecular weight peptides with a mass more than 8.7 kDa. The multiplicity of decrease in antigenicity with respect to the starting protein was 1.64×105 and 1.90×105, respectively. After repeated ultrafiltration the reduction in antigenicity of the obtained WPC alkalase or pancreatin hydrolysate was more than 1.0×106 and more than 5.0×105, respectively. The decrease in antigenicity of the CEP hydrolyzate obtained with proteolysis by alkalase and ultrafiltration compared to the initial CEP was 1.0×105 times, and 5.0×105 times when we used repeated ultrafiltration. A significant decrease in the content of high molecular weight peptides and a decrease in the antigenicity of peptide mixtures based on WPC and CEP to the values that permit their use in hypoallergenic products is achieved by combining proteolysis and double ultrafiltration through a UF10 membrane.

The macroprolactinemia phenomenon: origin and clinical diagnostic significance

The authors discuss the experimental and clinical data on the origin, properties, and diagnostic value of serum immunoreactive prolactin (irPRL) with a high molecular mass (macroprolactin, 100K-PRL). This form predominates in the blood of about 25% of women of a reproductive age with hyperprolactinemia. Comparison of the biochemical, immunochemical, and functional characteristics of the blood serum 100K-PRL and the monomeric fraction irPRL (23K-PRL) showed them to differ in principle. A low biological activity of 100K-PRL explains the absence of typical clinical signs of hyperprolactinemia in many women with macroprolactinemia. In contrast to 23K-PRL, 100K.-PRL weakly reacts to stimulants and inhibitors of PRL secretion by the pituitary. PRL-binding protein, apparently an immunoglobulin, is the basis of fraction 100K-PRL. The authors consider that analysis of not only total irPRL in the blood, but of its high and low-molecular forms be included in the algorithm of diagnostic search in some forms of hyperprolactinemia. This will help determine the treatment policy, because moderate hyperprolactinemia with predominating 100K- PRL as a rule cannot be corrected by dopamine agonists.

Enzymatic hydrolysates of food proteins for specialized foods for therapeutic and prophylactic nutrition

The review considers some issues of obtaining, as well as physic-chemical, organoleptic, immunochemical (residual antigenicity) characteristics of enzymatic hydrolysates from food proteins (EHFP) that are widely used in food products for various purposes, as well as assessing their biological activity. The results of experimental works and patents, which describe the most widely used approaches to the production of EHFP with desired properties (hydrolysates for therapeutic and prophylactic products), as well as assessments of biological activity and immunochemical properties are given. The use of various enzyme preparations (of bacterial, fungal and animal origin), as well as one- and two-stage hydrolysis schemes and options for instrumentation of fermentolysis processes are considered. It is concluded that in order to achieve the required reduction in antigenicity for hydrolysates used as part of therapeutic (hypoallergenic) foods (to values not higher than 10-5 relative to the antigenicity of the original protein) membrane ultrafiltration stages are necessary. The main disadvantage of such hydrolysates is their unsatisfactory organoleptic properties (bitterness and high osmolarity) that can be improved using a number of additional technological approaches. The use of partial hydrolysates (or hydrolysates with an average degree of hydrolysis, with a residual antigenicity of 10-4 to 10-5) with significantly better organoleptic properties compared with deep hydrolysates in therapeutic foods is considered. Of considerable interest are the issues of immunomodulatory, antioxidant and hypoallergenic properties of EHFP. It has been suggested that soybean and chicken egg hydrolysates may be promising as functional ingredients with antimicrobial, antihypertensive and immunomodulatory effects in various specialized foods, as well as in cases of food intolerance only to cow milk proteins.

Identification and mutational analysis of continuous, immunodominant epitopes of the major oyster allergen Crag 1

Shellfish, including oysters, often cause allergic reactions in children and adults. Oysters are inevitably consumed because of its delicacy and nutritional benefit, leading to frequent occurrence of severe clinical symptoms observed in patients with oyster hypersensitivity. We aimed to identify the immunodominant epitopes of oyster tropomyosin and crucial amino acids for IgE binding, which will help us to further understand the immunochemical characteristics of Cra g 1. The potential epitopes were predicted by immunoinformatics tools and the resultant immunodominant epitopes were identified by inhibition ELISA with pooled sera and individual serum from oyster allergic patients. Surprisingly, homologous substitution of multiple amino acids led to obviously decrease affinity of IgE antibodies, but this manner did not abrogate binding completely. Five major linear epitopes were evenly distributed on the surface of homology-based Cra g 1 model and hydrophilic residues appeared to be the most important for IgE binding. These results not only offer a better understanding of the molecular mechanism of interaction between Cra g 1 and oyster-specific IgE but also have significance in clinical diagnosis and immunotherapy.

Development and Preclinical Testing of a Vaccine for 3,4‐Methylenedioxypyrovalerone ((R,S)‐MDPV) Substance Use Disorders

Synthetic cathinones like 3,4‐methylenedioxypyrovalerone ((R,S)‐MDPV) are medically dangerous psychoactive drugs which at high doses produce psychosis, cardiovascular toxicity, and death. The goal for these studies was to develop and test a vaccine for treating ((R,S)‐MDPV) substance use disorders. A racemic MDPV conjugate vaccine was developed from a hapten structure capable of generating antibodies that bind with high affinity to (R,S)‐MDPV and other potent synthetic cathinones. We hypothesized that treatment with an optimized MDPV vaccine could produce high affinity antibodies against (R,S)‐MDPV capable of mitigating the pharmacological effects of (R,S)‐MDPV. An (R,S)‐MDPV‐like hapten was conjugated to different carrier proteins, mixed with Sigma Adjuvant System, and used to immunize male Sprague Dawley rats (n=5/group). The immunochemical characteristics of the rats' immune response was then evaluated. The KD value as determined by radioimmunoassay for (R,S)‐MDPV binding was 2.5 ± 1.9 nM, which demonstrated production of high affinity antibodies. The KD value for the individual (R)‐ and (S)‐MDPV binding was 0.71 ± 0.8 nM and 2.8 ± 2.3 nM, respectively. These similar KD values for the MDPV enantiomers indicates antibodies for both enantiomers contribute to the high binding of (R,S)‐MDPV. The rat antisera also showed similar high affinity binding of (R,S)‐α‐pyrrolidinovalerophenone (α‐PVP). No significant cross reactivity was detected with over‐the‐counter medications like (+)‐pseudoephedrine, neurotransmitters (dopamine, norepinephrine, epinephrine, and serotonin), or non‐cathinone drugs of abuse (cocaine, morphine, phencyclidine, (+)‐methamphetamine, (+)‐MDMA, and (−)‐MDMA). Moreover, the vaccination protocol produced high serum antibody titers, determined by rapid equilibrium dialysis, from 5 weeks after the start of immunizations until termination of the rats 3 months later. Finally, locomotor studies of control and vaccinated rats were conducted to test the vaccine's efficacy using a series of increasing doses of (R,S)‐MDPV (0.3–5.6 mg/kg, sc, 2 days apart). The immunized rats displayed significantly (p&lt;0.05) lower MDPV‐induced locomotor activity and a significantly shorter duration of action compared to controls. In conclusion, active vaccination with an (R,S)‐MDPV conjugate vaccine produced very high affinity antibodies against (R,S)‐MDPV; and the vaccinated rats showed significantly reduced (R,S)‐MDPV‐induced locomotor effects compared to controls.Support or Funding InformationFunded by NIDA grants DA039195 and T32 GM106999This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The evaluation of biological value and immunochemical characteristics of the coagulated chicken egg white

The aim of the study was to investigate in vivo the biological value of the coagulated chicken egg white on growing rats and a comparative immunochemical evaluation in vitro of its antigenic power. The experiment was carried out on 50 growing Wistar male rats with a body weight of 80±5 g. The animals were randomly divided into 3 groups (n=16): control group G1 and two experimental groups G2 and G3. The animals of the control group (G1) received a basic isocaloric and isonitrogenous (20% protein of casein by caloric content) semi-synthetic diet. The animals of the experimental groups G2 and G3 received the same semi-synthetic diet in which casein was replaced by chicken egg white (CEW) and coagulated CEW, respectively. The average food intake of group G3 animals, who received the CEW coagulate, was significantly lower (13.7±0.6 g per day, p<0.05) in comparison with the control group G1 (18.4±0.6 g) and the experimental group G2 (19.2±0.5 g). Moreover, body weight gain of animals treated with coagulated CEW didn't differ significantly from the control G1 animals. Already on the 8th day of the experiment, the body weight gain of G2 animals, who consumed native CEW, was significantly higher in comparison with both other groups. The protein efficiency ratio (PER) for animals of the G3 group was significantly higher (1.96±0.04) than the values for the animals of the control group G1 receiving casein (1.49±0.05, p<0.01), and for the animals of the experimental group G2 receiving CEW (1.60±0.02, p<0.05). The results of immuneenzymatic testing of the initial antigenic power of ovalbumin in native CEW indicated that its content was 33.0% relative to the standard ovalbumin value, antigenic power of which was assumed to be 100%. The developed process of coagulation contributed to a decrease in antigenic power to 2.17%. The obtained data indicate a high biological value and low antigenic power of the coagulated CEW, which makes it prospective for the usage in the composition of food products of mass demand and specialized food products.

Toxicity of the venom of Latrodectus (Araneae: Theridiidae) spiders from different regions of Argentina and neutralization by therapeutic antivenoms

“Black widow” spiders belong to the genus Latrodectus and are one of the few spiders in the world whose bite can cause severe envenomation in humans and domestic animals. In Argentina, these spiders are distributed throughout the country and are responsible for the highest number of bites by spiders of toxicological sanitary interest. Here, we studied the toxicity and some biochemical and immunochemical characteristics of eighteen venom samples from Latrodectus spiders from eight different provinces of Argentina, and the neutralization of some of these samples by two therapeutic antivenoms used in the country for the treatment of envenomation and by a anti-Latrodectus antivenom prepared against the venom of Latrodectus mactans from Mexico. We observed important toxicity in all the samples studied and a variation in the toxicity of samples, even in those from the same region and province and even in the same Latrodectus species from the same region. The therapeutic antivenoms efficiently neutralized all the venoms studied.

Влияние устойчивости томатов на морфо-физиологическое разнообразие и популяционные характеристики галловой нематоды Meloidogyne incognita (Kofoid, White, 1919), Chitwood, 1949

Objective of research: to provide data on the effect of tomato plants with different varietal resistance and immuno-chemical characteristics on the morpho-physiological and population features of root-knot nematode Meloidogyne incognita (Kofoid, White, 1919), Chitwood, 1949. Materials and methods: Tomato plants were infected and cultivated by standard methods. Parameters of nematodes (size, fertility, duration of life cycle, age and sex structure) of 156 lines in hybrids and cultivars of tomato Lycopersicon esculentum (Mill.) with different degrees of resistance to that nematode (resistance index 20% to 90%), as well the tomato cultivar (F1Karlson) which immune status was corrected with the use of immunomodulators. Results and discussion: The increased resistance of plants has a significant effect on total morpho-physiological and some population parameters (size, fertility, time to reach sexual maturity, terms of development, the number of males, etc.). This fact may indicate the modifying effect of immunity factors on parasites. Morpho-physiological features express a regular association between the level of immunity and standard features of parasitic invasions, which is required to ensure a relative stability of host-parasite systems in each particular case.