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The human immune repertoire retains the molecular memory of a very great diversity of target antigens (epitopes) and can recall this upon a second encounter with epitopes against which it has previously been primed. Although genetically diverse, proteins of coronaviruses exhibit sufficient conservation to lead to antigenic cross-reactions. In this review, our goal is to question whether pre-existing immunity against seasonal human coronaviruses (HCoVs) or exposure to animal CoVs has influenced the susceptibility of human populations to SARS-CoV-2 and/or had an impact upon the physiopathological outcome of COVID-19. With the hindsight that we now have regarding COVID-19, we conclude that although antigenic cross-reactions between different coronaviruses exist, cross-reactive antibody levels (titers) do not necessarily reflect on memory B cell frequencies and are not always directed against epitopes which confer cross-protection against SARS-CoV-2. Moreover, the immunological memory of these infections is short-term and occurs in only a small percentage of the population. Thus, in contrast to what might be observed in terms of cross-protection at the level of a single individual recently exposed to circulating coronaviruses, a pre-existing immunity against HCoVs or other CoVs can only have a very minor impact on SARS-CoV-2 circulation at the level of human populations.
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COVID-19 pandemic is an important public health concern in dengue endemic areas due to overlapping of clinical and laboratory features, representing a significant challenge for health care providers that often hampers a correct diagnosis and management of both diseases. Therefore, during the COVID-19 pandemic, healthcare providers in areas where dengue is endemic or who treat patients with recent travel history to these areas, need to consider dengue and COVID-19 in the differential diagnosis of acute febrile illnesses. Global Implications and Opportunities and COVID-19 have mild illness and do not require hospitalization, both diseases can cause severe illness that may result in death. Indeed, clinical management for people with severe illness due to either of these two diseases is quite different, often requiring hospital-based care. High index of suspicion is necessary in handling COVID-19 cases in tropical setting where dengue is endemic. Acute febrile cases with leucopenia and thrombocytopenia should be screened for dengue. Since false positive dengue serology or cross-reactivity with SARS-Cov-2 infections are known to occur, and have a potential impact on clinical outcome, or else, result in delay in COVID-19 or dengue appropriate treatment, the risk of occurrence of complications and death is increased.Copyright © 2023
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Introduction. The rapid spread of a new coronavirus infection among populations in many countries worldwide has contributed to the genetic evolution of the virus, resulting in the emergence of multiple genetic variants of the SARSCoV-2 coronavirus. Mutations in the viral genome can affect the ability of the virus to bypass the immune system and complicate development of diagnostic and prophylactic drugs. Data on the neutralizing activity of the sera obtained against previously circulating genetic variants of the virus in relation to current SARS-CoV-2 strains may serve as a scientific basis for the selection of the antigens in vaccine development. The aim of this work was to study cross-reactivity of SARSCoV-2 coronavirus strains belonging to different genetic variants, which were isolated in the territory of the Russian Federation during 2020-2022 in the neutralization reaction using mouse hyperimmune sera. Materials and methods. Ten strains of SARS-CoV-2 coronavirus belonging to different genetic variants were used (three non-VOC strains, alpha, beta, gamma, delta, delta+AY, omicron 1 and omicron 2). The hCoV-19/Australia/VIC01/2020 strain (Wuhan) was included in the study as a prototypical variant. BALBc mice were immunized with inactivated concentrated antigen mixed with a 1:1 adjuvant, which was a virus-like immunostimulatory complex based on Quillaja saponaria (Quillaja saponaria). The antibody titer was determined in the neutralization reaction. Results. Essential decrease of neutralizing ability of antibodies specific to non-vOC genetic variants of SARS-CoV-2 coronavirus was revealed against beta VOC and to a lesser degree against alpha and gamma VOC variants. The differences in the neutralizing activity level of antibodies for alpha and beta VOC variants are not significant among themselves, and with gamma VOC variants - there are no significant differences. Neutralizing ability of antibodies specific to delta VOC against alpha and beta VOC variants decreased 4-fold. Neutralizing activity of sera obtained to omicron 1 and 2 variants in relation to the prototype coronavirus variant was reduced 18-fold, to the gamma variant - 12-fold, to delta variants - more than 30-fold;for other variants it was even lower. Conclusions. The results obtained testify to the presence of cross-reactivity between strains of coronavirus belonging to genetic lines Wuhan, alpha, beta, gamma;it is weaker for delta variants. Mutations in the genome of VOC omicron variants led to a significant decrease in antigenic cross-links with earlier genetic variants of the coronavirus. These findings explain the low efficacy of vaccines based on the Wuhan strain, synthetic immunogens, and recombinant proteins based on it against omicron VOC variants, which have caused a rise in morbidity since early 2022, as well as cases of re-infection of humans with new genetic variants of the coronavirus.Copyright © 2023 Saint Petersburg Pasteur Institute. All rights reserved.
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Objective To develop a novel gold immunochromatographic double antibody sandwich assay for the detection of SARS-CoV-2 antigen, and to evaluate the performance of major reagents. Methods Potassium carbonate, large colloidal gold and SARS-CoV-2 antibody were used to prepare colloidal gold antibody markers, SARS-CoV-2 antibody concentration was optimized to prepare the binding pad, SARS-CoV-2 antibody and goat anti-mouse IgG were coated on nitrocellulose membrane as detection line and quality control line, according to the process requirements to assembly the assay. The minimum detection limit, cross-reactivity, accelerated stability test and clinical evaluation of the antigen detection reagent were determined. Results The minimum detection limit of SARS-CoV-2 inactivated virus was 3. 3×10~2 TCID50/ml, and no cross-reaction was found in the samples containing 10 common pathogens. The results of 37 °C high temperature accelerated test for 28 d showed high stability of the reagent. The sensitivity, specificity and total coincidence rate were 92. 00%, 100. 00% and 98. 67% and the Kappa value of concordance test was 0. 939, P＜0. 01. Conclusion The developed antigen detection assay has high sensitivity and specificity, which is also simple to operate in a short time. It can be used as a rapid detection method for large-scale screening of novel coronavirus.
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Introduction: Subacute thyroiditis is a self-limiting post-viral inflammatory disorder occurring in 3 phases (hyper-, hypo-, and euthyroidism) Post-vaccine thyroiditis has also been reported, but is rare. Case Description: A 36-year-old Emirati female presented to our clinic with generalized fatigue, mild to moderate vague neck pain, intermittent palpitations, and loss of appetite 2 weeks after receiving her first dose of Pfizer-BioNTech mRNA vaccine against COVID-19. Clinical examination findings and laboratory test results were consistent with subacute thyroiditis. Patient is a mother of 5 healthy children, youngest is breast-fed infant (11 months old). There was no history suggestive of postpartum thyroiditis and no family history of thyroid dysfunction. Physical examination at initial visit showed mild tachycardia, and a normal blood pressure. She weighed 66 kg. Thyroid function tests revealed a suppressed TSH of 0.011 muIU/mL, high Free T4 of >100 pmol/l), and Free T3 FT3 of 29.6 pmol/L. Both TSH receptor antibodies, and Thyroid antibodies (TPO) were negative. Thyroid scintigraphy showed decreased uptake in both lobes. Thyroid ultrasound showed hypoechoic heterogeneous echotexture of the thyroid gland with vascular conglomerate and micro-calcification, along with normal sized reactive lymph nodes at sternal angle. Symptoms aggravated through the next week;patient dropped 3kg of her body weight and her palpitations increased, with a recorded resting heart rate between 120-130 beats/min. TSH decreased to 0.001muIU/mL while FT4 remained high, with an improvement to 90 pmol/L. Subsequently, the patient started to regain weight. Palpitations improved within a month. She developed a biochemically hypothyroid picture followed by clinical and biochemical euthyroidism after one more month. Second dose of the vaccine was uneventful. Last evaluation was 10 months later;TSH, FT3 and FT4 were all in normal range, acute-phase reactants were completely normal and in complete remission. Discussion(s): The exact mechanism for post-vaccination subacute thyroiditis remains unknown, vaccine adjuvants may induce diverse autoimmune and inflammatory reaction. Subacute thyroiditis has rarely been reported with other COVID-19 vaccines contains no Polyethylene glycol (PEG). A possible cross-reactivity between thyroid cell antigens and spike protein of the coronavirus produced by mRNA vaccines might be responsible. Further research is needed to investigate the incidence of subacute thyroiditis in COVID-19 pandemic days.Copyright © 2023
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To establish a PCR detection method for Trichomonas foetus, the primers were designed and synthesized according to the 18S rRNA gene sequence of T. foetus published by GenBank. The positive recombinant plasmid pUCm-T-TF18S of T. foetus was used as the template, and the genomic DNA of Giardia felis, Coccidia +e-lis, feline parvovirus and cDNA of feline coronavirus were used as the control for PCR detection to analyze the specificity of this method. The positive T. foetus recombinant plasmid was serial to 8 different concentrations with a gap of 10 folds, and PCR was performed to analyze the sensitivity of this method. The pUCm-T-TF18S plasmids stored at -20 " for 3, 6, 9 and 12 months were detected by PCR to analyze the stability of the method. Twenty cat fecal samples were tested using this established PCR assay and compared with those of microscopic examination. The results showed that the recombinant plasmid pUCm-T- TF18S gave specific bands after PCR amplification. The sequencing results showed that the length of the product sequence was 1 264 bp, and the BLAST sequence comparison analysis showed 99.53% sequence identity, which is consistent with that of T. foetus from cats (GenBank registration number M81842.1). The PCR method for detection of T. foetus had no cross-reactivities with C. felis, G. felis, feline coronavirus and feline parvovirus;the minimum detectable template concentration is 4.52 X 105 copies/xl;The target band of T. foetus DNA can still be detected after being stored in the refrigerator at -20 " for 12 months. This method detected 16 positive samples of T. foetus nucleic acid from 20 cat fecal samples, which is more accurate and sensitive than the results from traditional microscopy (13 samples). It is suggested that the PCR method for the detection of T. foetus is highly specific, sensitive and stable, and can be used for clinical detection and epidemiological investigation of T. foetus.Copyright © 2022, National Institute of Parasitic Diseases. All rights reserved.
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Background: T cells play a critical role in the adaptive immune response to SARS-CoV-2 in both infection and vaccination. Identifying T cell epitopes and understanding how T cells recognize these epitopes can help inform future vaccine design and provide insight into T cell recognition of newly emerging variants. Here, we identified SARS-CoV-2 specific T cell epitopes, analyzed epitope-specific T cell repertoires, and characterized the potency and cross-reactivity of T cell clones across different common human coronaviruses (HCoVs). Method(s): SARS-CoV-2-specific T cell epitopes were determined by IFNgamma ELISpot using PBMC from convalescent individuals with mild/moderate disease (n=25 for Spike (S), Nucleocapsid (N) and Membrane (M)), and in vaccinated individuals (n=27 for S). Epitope-specific T cells were isolated based on activation markers following a 6-hour peptide stimulation, and scRNAseq was performed for TCR repertoire analysis. T cell lines were generated by expressing recombinant TCRs in Jurkat cells and activation was measured by CD69 upregulation. Result(s): We identified multiple immunodominant T cell epitopes across S, N and M proteins in convalescent individuals. In vaccinated individuals, we detected many of the same dominant S-specific epitopes at similar frequencies as compared to convalescent individuals. T cell responses to peptide S205 (amino acids 817-831) were observed in 56% and 59% of individuals following infection and vaccination, respectively, while 20% and 19% of individuals responded to S302 (a.a. 1205-1219) following infection and vaccination, respectively. For S205, a CD4+ T cell response, we confirmed 8 unique TCRs and determined the minimal epitope to be a 9mer (IEDLLFNKV). While TCR genes TRAV8-6*01 and TRBV30*01 were commonly utilized across the TCRs, we did identify TCRs with unique immunogenetic properties with different potencies of cross-reactivity to other HCoVs. For S302, a CD8+ T cell response, we identified two unique TCRs with different immunogenetic properties that recognized the same 9mer (YIKWPWYIW) and cross-reacted with different HCoV peptides (Figure 1). Conclusion(s): These data identify immunodominant T cell epitopes following SARS-CoV-2 infection and vaccination and provide a detailed analysis of epitope-specific TCR repertoires. The prospect of developing a vaccine that broadly protects against multiple human coronaviruses is bolstered by the identification of conserved immunodominant SARS-CoV-2 T cell epitopes that cross react with multiple other HCoVs.
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Case report Trometamol (tromethamine, tris(hydroxymethyl)aminomethane (TRIS)) is an excipient frequently used as buffer in fluids and semisolid agents, including many drugs such as antibiotics, iodinated contrast agents and the COVID-19 vaccine mRNA-1273. Here, we report the first case of a delayed-type hypersensitivity after oral intake of trometamol. A 64-year- old female patient presented to our emergency department with generalized erythematous rash, pruritus and swelling of the face five hours after the intake of one tablet of fosfomycin trometamol for a urinary tract infection. Further medical history revealed a previous erythematous rash five to six hours after administration of the iodinated contrast agent iopromide. We performed skin prick and intradermal tests with trometamol, fosfomycin trometamol and various iodinated contrast agents, including iopromide, iomeprol, iobitridol, iopamidol and iodixanol. These tests showed no reactions initially. However, 48 hours after intradermal testing, macular erythematous lesions developed at the sites tested with trometamol 0.1%, trometamol 0.01% and all sites tested with iodinated contrast agents. Furthermore, when we performed a lymphocyte transformation test with trometamol, fosfomycin trometamol and iopromide, we recorded a positive reaction with cytokine release after stimulating T cells with trometamol and iopromide. In contrast, basophil activation testing showed a negative result for these agents. Based on these results and our patient's history, we diagnosed a clinically relevant type IV sensitization to trometamol. There are only a few case reports about immediate-type allergic reactions to gadolinium contrast agents caused by the excipient trometamol. There are some published cases which report contact dermatitis after topical administration of trometamol-containing agents. To our knowledge, ours is the first case to report a delayed hypersensitivity reaction to oral administration of trometamol. Excipients are indispensable for drugs, vaccines and other products since they stabilize and preserve the active agents. Nevertheless, excipients should always be considered during an allergy workup, especially if the patient reports prior drug reactions that cannot be explained by a chemical cross-reaction. In our case, we diagnosed delayed-type hypersensitivity to the excipient trometamol. This is a consequential diagnosis for the patient, because trometamol is contained in many drugs and in the COVID-19 vaccine mRNA-1273.
ABSTRACT
Background: Covid 19 is a global epidemic. One of the most important steps in the fight against this epidemic is vaccination. mRNA vaccines are used in vaccination in our country. Among the additives in the vaccine, the substance with the highest allergenic risk is polyethylene glucose (PEG). There are different molecular weights of PEG. Another additive that has a high risk of cross-reaction with PEG as an additive is POLISORBAT 80. Skin tests with drugs containing PEG and POLISORBAT 80 and, if available, tests with vaccines are instructive. Among the drugs containing PEG: Moxifloxacin tablet, ciprofloxacin tablet, Amoxicillin clavulanic acid tablet;Medicines containing polysorbate include: Omalizumab vaccine, Mepolizumab vaccine. The results of the skin test with PEG-containing methylprednisolone (DEPO-MEDROL) and POLYSORBAT-containing triamcinolone (KENACORT-A) in order to be evaluated in terms of vaccine in our 2 patients who had multiple drug sensitivities before were shared. Method(s): Case 1: 33 y, F *There are diagnoses of urticaria and angioedema. Urticaria 30 minutes after taking aspirin, levofloxacin, cefdinir tablet;5 minutes after taking ciprofloxacin tablets, he has anaphylaxis. *Applies before Biontec vaccine. *The patient had a history of anaphylaxis with PEG-containing ciprofloxacin. In the skin tests performed with DEPO-MEDROL and KENACORT-A, 1/100 intradermal test was positive. *The patient for whom Biontec vaccine was not recommended received Synovac vaccine without any problems. Case 2: 52 years, F * He has a diagnosis of urticaria. 5 minutes after general anesthesia and local anesthesia;The patient who had cardiac arrest 3 times was evaluated. The patient, who had Synovac for 2 times without any problems, wanted to have the 3rd dose of Biontec vaccine. *Tested with general -local anesthetic agents. *Ciprofloxacin skin tests are negative;Urticaria plaques developed after 30 minutes of 1/4 tb in oral provocation. In the skin tests performed with DEPO-MEDROL and KENACORT-A, 1/100 intradermal test was positive. *Biontec vaccine is not recommended. Result(s): A safer vaccination is ensured by testing with additives in Covid 19 vaccines. Conclusion(s): Drug additives should also be kept in mind in patients with multiple drug allergies.
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In a study of two Hospitals in Saxony (Chemnitz and Leipzig), we analyzed the antibody development towards SARS-CoV-2 and against a variety of endemic coronaviruses. Here we analyzed 760 sera from a Saxonian cohort for antibody reactivity against: Common cold coronaviruses, HCoV-229E, HCoV-HKU 1, HCoV-NL63 and HCoV-OC43, MERS-CoV and SARS-CoV. For the SARS CoV-2 immune response we tested the following antigens: Spike, S1, S2, RBD and nucleocapsid. These 11 antigen determinants were tested in a commercial multiplex Luminex based assay. We tested sera from 544 individuals (347 females and 197 males;498 SARS-CoV-2 PCR positive and 262 SARS-CoV-2 PCR negative) between May 2020 and March 2022. We observed up to 10% reactivity against the MERS virus in both the PCR positive and negative group. Against the common cold corona viruses 80%-90 % of the individuals in both groups show detectable antibodies. Regarding the antibody response against SARS-CoV a significant difference was observe. Only 19% of COVID-19 infected individuals show antibodies against the virus, while 81% of the PCR-positive individuals produced antibodies. The presence of antibodies against the SARS-CoV-2 is positively correlated with those against SARS-CoV (p = 0.001). No changes in endemic antibody responses were see in the two groups. The antibody status after first immunization event (infection/ vaccination) shows differences in nucleocapsiddirected antibody production, found in the natural infection group (about 60%). In the vaccination group, more individuals (up to 95%) show an immune response against Spike, S1 and RBD compare with natural infection. In summary, the examined cohort shows a general immunization up to 90% against most endemic corona viruses. Correlation analyses show cross-reactivity between SARS-CoV-2 and SARS-CoV. Longitudinal antibody analyses are under way, as also correlations of humoral response with immunogenetic factors.
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The coronavirus disease-19 (COVID-19) signs mostly include fever and respiratory symptoms (unusual viral pneumonia by SARS-Coronaviruses 2 or SARS-CoV-2). The Receptor-Binding Domain (RBD) of COVID-19 and SARS-CoV are similar, causing cross-reactivity of anti-SARSCoV antibodies with associated spike protein, exerting promising implications for rapid development of vaccines and therapeutic antibodies against COVID-19. ACE2 is the SARS TMPRSS2 for spike (S) protein receptor for initiation of infection;hence, it is a target for pharmacological intervention. Furthermore, designing novel monoclonal antibodies binding specifically to COVID-19 RBD is essential. A viral S proteins (TMPRSS2) was proposed for clinical use by blocking the viral intake by cell.Copyright © 2020, Health Biotechnology and Biopharma. All rights reserved.
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Background: Covid-19 viral infection affects strongly the populations in the world by the level of morbidity, mortality and the economic impact. A worldwide vaccination program was developed since the end of 2020 to limit the propagation of the virus and the development of variants. In USA and Europe the risk of an allergic reaction is estimated to be 1.31 (95 % CI, 0.90-1.84) per million vaccine dose. The excipients are considered to be the most probable cause of IgE-mediated allergic reactions: PolyEthylene Glycol (PEG) for the Moderna and the Pfizer-BioNTech vaccines and Polysorbate 80 (P80) for the Astra Zeneca and the Johnson & Johnson. P80 presents clinical cross-reactivity with PEG. Patients with a history of severe allergic reaction to PEG or P80 should avoid the vaccination. However, some of them strongly wanted to be vaccinated because their accumulated risk factors for severe infection. Method(s): To 4 severely PEG/P80 allergic patients (grade 3 of anaphylaxis), we proposed a desensitization protocol (7 steps in 90 min + 60 min of observation) with the Pfizer-BioNTech vaccine. Each injection was performed alternately in the deltoid muscle (SC for 2 treated by apixaban) every 15 min. Two patient received all the injections in the same arm due to insufficient lymphatic drainage post mastectomy. The protocol was repeated 1 month and once again 6 months later for the second and the booster doses respectively. One patient didn't received the last one because she was meanwhile moved in palliative treatment. We followed the modification of their immunological status. All patients took a premedication with bilastine 20 mg and montelukast 10 mg (without PEG/P80) 24 h and 3 h before each protocol. Result(s): No patient developed adverse nor allergic reaction after the successive vaccinations. Conclusion(s): We c an p ropose adesensitization protocol to the COVID-19 Pfizer-BioNTech vaccine to patients with severe hypersensitivity to PEG/P80. The desensitization is well tolerated and followed by an increase of specific antibodies and an evolution of antibody level like patients who received the total dosis (0.3 ml) in one injection. (Figure Presented).
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Background: Drug hypersensitivity reactions (DHRs) of the immediate type are diagnosed in approximately 1-2% per 100 thousand people. During the COVID-19 pandemic, the use of antibiotics increased, and cases of immediate reactions to these drugs became more frequent. However, due to the lack of medical centers which have the necessary conditions for carrying out provocation tests, the use of in vitro diagnostic methods for hypersensitivity reactions to antibiotics is becoming even more relevant during the pandemic. Flow CAST Basophil Activation Test (BAT) Flow Cytometry can be used for the in vitro detection of immediate type allergic reactions and hypersensitivities to suspected allergens in patients at risk for DHRs. The purpose is to study the possibility of diagnosing hypersensitivity reactions to antibiotics using BAT to antibiotics. Method(s): The Patient Questionnaire Card and the Patient Review Card were used to survey 32 (8.7%) individuals (f -56.3%, m -43.7%) who met the inclusion criteria (the presence of hypersensitivity reactions to beta-lactam antibiotics during the last 3 years). We used Flow CAST to identify the DHRs to beta-lactam antibiotics (Ceftriaxone (conc. 4 mg/ml);Cefuroxime (conc. 2.5 mg/ml);Amoxicillinum (conc. 2.5 mg/ml) from CAST Allergens for CASTFlow CAST) BUHLMANN LABORATORIES AG, Switzerland) in whole blood. Flow cytometric acquisition was performed on a flow cytometer BD FacsCalibur (USA), and 300 basophilic cells were analyzed. Result(s): The most common clinical manifestations included acute urticaria + angioedema (40.6%), generalized urticaria (28.1%), anaphylactic shock (21.9%), bronchospasm (9.4%). The percentage of patients diagnosed with an immediate reaction based on the time of its occurrence was 62.5%, whereas the percentage of patients diagnosed with an immediate reaction based on the clinical manifestations was 81.25%, which was confirmed by positive BAT results (p > 0.05). 68.75% of people with clinical manifestations of reactions to one antibiotic (ceftriaxone or amoxicillin) showed increased values on the BAT test to other beta antibiotics, which may indicate the presence of cross-reactivity between these groups of drugs. Conclusion(s): Diagnostics of immediate hypersensitivity reactions to antibiotics based on in vitro BAT is a highly accurate method. However, in cases of possible cross-reactivity between antibiotics and in cases of delayed reactions, in-depth studies are required.
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Case report Purpose: To report two cases of reactivation of BCG vaccination scars, the first after mRNA -SARS- CoV2 -vaccine and the second after SARS-CoV2 infection. Case 1: A 33 year-old woman, a nursing assistant, was referred with erythema and swelling of her BCG vaccination scar 24 hours after receiving her second dose of the BNT162b2 mRNA vaccine (Pfizer-BioNTech) and, 10 months later, after receiving her third dose with the mRNA-1273 (Moderna) vaccine. Case 2: A 60 year-old woman, a medical doctor, was referred with erythema and swelling of her two BCG vaccination scars (one administered at birth and the second one at the age of 10), 12 days after testing positive for SARS-CoV2 associated with homolateral supraclavicular and axillary adenopathy's . In both cases, total IgE values and D-dimer were normal and symptoms resolved spontaneously within 7 days, without further treatment. Discussion(s): Bacillus Calmette-Guerin (BCG) local scar inflammatory reactions have been described with Kawasaki disease in children, with other viral infections such as measles and human herpesvirus type 6 (HHV6) infection and following influenza vaccination. The relationship between the BCG vaccine and SARS-CoV2 remains unclear. Even in mid-2020 and during the first years of the pandemic, it was proposed that the BCG vaccine could be protective against SARS-CoV2 infection. Several studies were launched to evaluate this hypothesis, with no conclusive results in this regard. Along the last two years, some cases of reactivation of BCG vaccination scars have been reported after vaccination with mRNA -SARS- CoV2 -vaccines. To our knowledge, this is the first reported case of reactivation of BCG vaccination scars after SARS-CoV2 infection. Conclusion(s): We report the first case of BCG vaccine scar inflammation as a local reaction following SARS-CoV2 infection. The reactivation of BCG vaccine scar after receiving mRNA vaccines and after SARS-CoV2 infection might have been caused by an immunological reaction due to a cross reactivity phenomenon between BCG and SARS-CoV2. The immunological and clinical implication of this reaction needs to be further studied. Clinicians need to be aware of this local reaction to SARS-CoV2 vaccines and infection. (Figure Presented).
ABSTRACT
T cells, and especially cytotoxic T cells are at the forefront of the fight against viral infection. The killer cells are able not only to distinguish between self and foreign peptides, but also to engage in the fight to clear the viral infection by eliminating the infected cells. Our lab is focused on understanding how T cells engage with viral peptide antigens, that are presented by highly polymorphic HLA molecules. T cells have receptors on their surface called T cell receptors (TCRs) that allow them to recognize the composite surface of the peptide- HLA complex. Using x-ray crystallography we can understand at the atomic level both peptide antigens presentation and TCR recognition, both important to determine the quality of the subsequent immune response. We can then link that structural information with our cellular assay that determines the strength and magnitude of the anti-viral response, providing the basis for peptide modification to reach stronger response or an understanding of viral mutation that led to viral escape. Our current work compared the T cell response, at the antigen level against 32 single epitope derived from spike, between COVID-19 recovered and vaccinated donors. We have shown that the booster shot (3rd dose) increases the antigen-specific T cell response, increases the level of T cell cross-reactivity against variant of SARS-CoV-2, but also alters the phenotype of the T cell. Those results are important to future guide vaccination advise and better understand the immune response to SARS-CoV-2 infection. POSTER PRESENTATIONS Autoimmunity, Infection, Reproduction and Cancer.
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Various antibody therapeutics has been developed for the treatment and suppression of the 2019 outbreak of novel coronavirusSARS-CoV-2infection. A major limitation in the development DDS of SARS-CoV-2 neutralizing antibodies is the occurrence and spread of escape variants that have mutations in the spike glycoprotein. The coronaviruses are carried by various wild animals, domestic animals, and pets, and there have been cases of Severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus transmission from animals to people, resulting in a large spread of infection in people. There is also a possibility that cross-species transmission of SARS-CoV-2 may occur in the future. Considering these factors, the development of antibody therapeutics with broad cross-reactivity against SARS-CoV-2 variants and other coronaviruses is required.Copyright © 2022, Japan Society of Drug Delivery System. All rights reserved.
ABSTRACT
Various antibody therapeutics has been developed for the treatment and suppression of the 2019 outbreak of novel coronavirus(SARS-CoV-2)infection. A major limitation in the development DDS of SARS-CoV-2 neutralizing antibodies is the occurrence and spread of escape variants that have mutations in the spike glycoprotein. The coronaviruses are carried by various wild animals, domestic animals, and pets, and there have been cases of Severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus transmission from animals to people, resulting in a large spread of infection in people. There is also a possibility that cross-species transmission of SARS-CoV-2 may occur in the future. Considering these factors, the development of antibody therapeutics with broad cross-reactivity against SARS-CoV-2 variants and other coronaviruses is required.Copyright © 2022, Japan Society of Drug Delivery System. All rights reserved.
ABSTRACT
Various antibody therapeutics has been developed for the treatment and suppression of the 2019 outbreak of novel coronavirus(SARS-CoV-2)infection. A major limitation in the development DDS of SARS-CoV-2 neutralizing antibodies is the occurrence and spread of escape variants that have mutations in the spike glycoprotein. The coronaviruses are carried by various wild animals, domestic animals, and pets, and there have been cases of Severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus transmission from animals to people, resulting in a large spread of infection in people. There is also a possibility that cross-species transmission of SARS-CoV-2 may occur in the future. Considering these factors, the development of antibody therapeutics with broad cross-reactivity against SARS-CoV-2 variants and other coronaviruses is required.Copyright © 2022, Japan Society of Drug Delivery System. All rights reserved.
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Background: The coronavirus disease 2019 (COVID-19) pandemic continues to cause widespread disruption to daily life globally. With increasing levels of vaccination and the emergence of new variants, it is important to monitor and identify individuals who have produced an immune response to SARS-CoV-2 and those who may remain at higher risk. Aims & Objectives: This study aimed to evaluate the clinical performance of a serological anti-SARS-CoV-2 Immunoglobulin G (IgG) Enzyme-Linked Immunosorbent Assay (ELISA), initially created by AstraZeneca and further developed and validated by ProAxsis Ltd. Method(s): The ProAxsis ELISA was used to assess anti-SARS-CoV-2 IgG levels in 402 positive and 701 negative plasma samples. Samples from each of the SARS-CoV-2 genetic variants (alpha, delta and omicron), along with the World Health Organisation International Reference Panel (NIBSC:20/268) and a panel of seroconversion samples were also tested. Result(s): Sensitivity and specificity of the ProAxsis Anti-SARS-CoV-2 IgG ELISA was 100.0% (CI 95% = 99.1- 100.0%) and 99.3% (CI 95% = 98.3-99.8%) respectively. The ProAxsis and comparator test (Euroimmun) were in almost perfect agreement, Cohen's Kappa (kappa) = 0.991 (CI 95% = 0.982-0.999, p<0.0001). Seroconversion was observed with the ProAxsis ELISA at an earlier stage than with the comparator assay. Of the 101 virology samples tested only one sample (Anti-malaria plasma P.falciparum) displayed some cross-reactivity. Conclusion(s): The ProAxsis Anti-SARS-CoV-2 IgG ELISA demonstrated excellent clinical performance in comparison to a comparator assay and will be highly useful in identifying individuals who have raised antibodies following exposure to SARS-CoV-2 or vaccination.
ABSTRACT
Although onset/exacerbation of bullous Pemphigoid (BP) has been reported to occur frequently following exposure to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the link, if any, between BP dermatoses and the viral infection remains obscure. Therefore, searching for possible molecular mechanisms, we hypothesise that molecular mimicry between BP antigens and the SARS-CoV-2 proteins might lead to autoimmune responses cross-reacting with the BP proteins, thus triggering the dermatosis pathologies. Using this research paradigm, we analyzed the Bullous Pemphigoid antigen 1 (BP230) and the SARS-CoV-2 proteome to share minimal immune determinants, i.e., pentapeptides. Results indicate a high level of molecular mimicry between BP230 and SARS-CoV-2, thus supporting the hypothesis of cross-reactivity as a possible major mechanism in the SARS-CoV-2-associated BP etiopathogenesis.Copyright © by BIOLIFE, s.a.s.