Serum Antibody Research Articles

Intranasal parainfluenza virus-vectored vaccine expressing SARS-CoV-2 spike protein of Delta or Omicron B.1.1.529 induces mucosal and systemic immunity and protects hamsters against homologous and heterologous challenge.

The continuous emergence of new SARS-CoV-2 variants requires that COVID vaccines be updated to match circulating strains. We generated B/HPIV3-vectored vaccines expressing 6P-stabilized S protein of the ancestral, B.1.617.2/Delta, or B.1.1.529/Omicron variants as pediatric vaccines for intranasal immunization against HPIV3 and SARS-CoV-2 and characterized these in hamsters. Following intranasal immunization, these B/HPIV3 vectors replicated in the upper and lower respiratory tract and induced mucosal and serum anti-S IgA and IgG. B/HPIV3 expressing ancestral or B.1.617.2/Delta-derived S-6P induced serum antibodies that effectively neutralized SARS-CoV-2 of the ancestral and B.1.617.2/Delta lineages, while the cross-neutralizing potency of B.1.1.529/Omicron S-induced antibodies was lower. Despite the lower cross-neutralizing titers induced by B/HPIV3 expressing S-6P from B.1.1.529/Omicron, a single intranasal dose of all three versions of B/HPIV3 vectors was protective against matched or heterologous WA1/2020, B.1.617.2/Delta or BA.1 (B.1.1.529.1)/Omicron challenge; hamsters were protected from challenge virus replication in the lungs, while low levels of challenge virus were detectable in the upper respiratory tract of a small number of animals. Immunization also protected against lung inflammatory response after challenge, with mild inflammatory cytokine induction associated with the slightly lower level of cross-protection of WA1/2020 and B.1.617.2/Delta variants against the BA.1/Omicron variant. Serum antibodies elicited by all vaccine candidates were broadly reactive against 20 antigenic variants, but the antigenic breadth of antibodies elicited by B/HPIV3-expressed S-6P from the ancestral or B.1.617.2/Delta variant exceeded that of the S-6P B.1.1.529/Omicron expressing vector. These results will guide development of intranasal B/HPIV3 vectors with S antigens matching circulating SARS-CoV-2 variants.

348 Repeat breeding syndrome: Dexamethasone decreases the prevalence of anti-sperm antibodies in dairy cows

Abstract Cows that require greater than two inseminations to conceive are diagnosed with repeat breeding syndrome (RBS). Anti-sperm antibodies (ASA) in serum are in greater abundance among individuals exhibiting fertility challenges. In humans, treatment with glucocorticoids has been shown to decrease the prevalence of ASA and improve fertility. Therefore, the purpose of this study was to determine the impact of dexamethasone on ASA and pregnancy outcomes in RBS cattle. Holstein multiparous cows (n = 18) diagnosed as having RBS were randomly allotted to one of three treatment groups: Control (C; n = 6), low dexamethasone (LD; n = 6) and high dexamethasone (HD; n = 6). Intramuscular injections of saline (C), 0.05 mg/kg of BW of dexamethasone (LD), or 0.10 mg/kg of BW of dexamethasone (HD) were administered daily starting 4 d prior to insemination (d 0) through insemination (d 4). All treatment volumes were standardized with saline to achieve the same treatment level. Blood was collected on d 0, 4, 8 and 18, with serum extracted on d 0 through 8. Additionally, milk weights were recorded until d 34. For breeding, cows were synchronized using the Double Ovsynch protocol and only one insemination was conducted at the time of breeding. The MIXED procedure in SAS was used to determine the relationship of treatment with the repeated measures of ASA abundance and milk yield. Additionally, a non-parametric chi-square analysis was conducted in SAS using PROC GENMOD to determine the relationship of treatment with immune cell count and pregnancy outcomes. Day, Treatment and Treatment × Day were designated as fixed effects, and a protected post hoc analysis was conducted to account for multiple comparisons. Anti-sperm antibodies tended to decrease (P ≤ 0.082) as dexamethasone increased compared with C, however, there was no Treatment × Day interaction. Daily milk yields for both LD and HD decreased (P < 0.002) compared with C cows, but there was no interaction with day. Though there was an effect for Treatment × Day (P ≤ 0.002) for white blood cell count, percentage lymphocytes, eosinophils, and neutrophils, there was no effect of treatment (P ≥ 0.181). Therefore, interaction differences were largely driven by day (P < 0.001). Surprisingly, there was a trend (P = 0.069) for an increase in pregnancy rates for C cows compared with LD and HD cows. In fact, one-half of the C cows achieved pregnancy compared with just one cow for LD and HD treatments. Overall, dosage of dexamethasone did not differ for ASA or pregnancy outcomes. However, dexamethasone did decrease ASA but did not increase pregnancy rates. Based on these results, we suggest that alternative treatment measures should be explored to improve pregnancy rates in RBS cows.

PRODUCTION OF RECOMBINANT SALMONELLA ABORTUS EQUI PROTEINS

The cause of mare abortions of salmonellosis etiology is pathogen Salmonella abortusequi. The economic damage caused by this infection is due to the loss of reproductive capacity of the sires, litter failure, reduced productivity and veterinary costs. High level of infection of horses is registered in many countries, including Kazakhstan. The main method of diagnosis is bacteriological, but its disadvantages are low sensitivity and duration of results. The OIE recommends the use of PCR and ELISA for diagnosis of infection, however, due to the high cost of test systems, the use of PCR in veterinary laboratories is not always justified, and the effectiveness of the ELISA method depends largely on the structure and purity of the antigen. Currently, genetic engineering methods make it possible to obtain recombinant antigens of animal pathogens containing separate proteins, which excludes the occurrence of nonspecific reactions. These antigens can be used in tests for serological diagnostics, immunization of laboratory animals, and in the development of vaccines. According to literature data, it is known that diagnostically significant antigens in bacteria of the genus Salmonella are outer membrane proteins. Therefore, the outer membrane protein OmpX of S. abortusequi, which has high immunogenicity and conservativeness was selected as a target. The aim of this work is to obtain recombinant OmpX antigens of S. abortusequi and study their properties. As a result, E. coli strains producing recombinant OmpX protein of S. abortusequi were created. The synthesized genes were cloned into expression vectors and transformed into competent E. coli BL21 cells. The rOmpX of Salmonella abortusequi was produced and purified; electrophoretic analysis showed the purity of the preparation with a molecular mass of 23 kDa. The recombinant protein was analyzed by LC/MC-MC spectrometry, and peptides containing QTTDYPTYKHDTSDYGFSYGAGLQFN amino acid sequences were identified. A search of the peptide spectrum in the SwissProt database showed that they corresponded to the OmpX protein of Salmonella abortusequi. To determine the quality of protein refolding and the conservation of antigenic epitopes of the protein, Western blot was used with control positive sera that specifically reacted with a protein of molecular mass 23kDa. The resulting recombinant OmpX protein was then used as an antigen in an indirect ELISA to detect antibodies in serum samples from aborted mares. The results of n-ELISA showed the presence of antibodies in serum at a titer of 1:1600 (+26.6; - 21.1). Thus, rOmpX of S. abortusequiwith a molecular mass of 23 kDa was obtained and its main properties were studied. The correctness of protein refolding was confirmed by Western blot and ELISA with positive control sera. The specificity of recombinant proteins was proved by interaction with positive serum samples of horses from unfavorable farms. The obtained recombinant antigens can be used in the creation of tests for the diagnosis of salmonellosis abortion of horses in the Republic of Kazakhstan. WPM с добавлением БАП 1,0 мг/л, ИМК 0,1 мг/л, ГК 0,2 мг/л, где было в среднем образовано 7,36 микропобегов на один эксплант.

THE RECOMBINANT BACTERIA LACTOCOCCUS LACTIS EXPRESSING SARS-COV-2 SPIKE PROTEIN OR ITS RECEPTOR-BINDING DOMAIN ELICITS AN IMMUNE RESPONSE FOLLOWING ORAL IMMUNISATION OF RATS

Mucosal delivery of antigens represents an effective strategy for the development of vaccines to control diseases with the upper respiratory and/or gastrointestinal tracts as the main routes of transmission. Lactic acid bacteria (LAB) are food-grade bacteria used for the expression of target antigens in the development of mucosal vaccines. Over the last two decades, research on the use of LAB has focused on the construction of genetically modified strains. Current study aimed to develop and examine the recombinant Lactococcus lactis strains, expressing SARS-CoV-2 spike (S) protein or the receptor-binding domain (RBD) of S protein as immunizing antigens.The spike gene from the component II of Sputnik V vaccine and two synthesized coding sequences of the RBD region of SARS-CoV-2 spike protein (319–529 residues named HA-spike and 318–590 residues named mini-spike) were subcloned into expression vector pNZ8121. The resulting plasmids were verified by sequencing and subsequently transformed into competent L. lactis NZ3900 cells. The expression of recombinant proteins in obtained strains was analyzed by western blot using SARS-COV-2 Spike RBD antibodies. The results showed that the spike gene could be efficiently expressed in the cells of recombinant L. lactis. The major 150 kDa band detected in the cell lysate of L. lactis pNZ::spike represented the full-length S protein. Protein bands of 35 kDa and 23 kDa from the lysates of L. lactis pNZ::mini-spike and L. lactis pNZ::HA-spike respectively were detected indicating that the recombinant RBD protein was also successfully expressed. The mini-spike was expressed more abundantly than the HA-spike variant. Based on the growth kinetics and protein expression profiles of recombinant strains, the highest protein yield was obtained under the following conditions: overnight culture was inoculated (1/25 inoculum) and grown until reaching an optical density of 0,9 at 600 nm, then gene expression was induced by adding nisin (1 ng/ml), cells were harvested after 3 h incubation with the inducer. To examine the immunogenicity of recombinant strains, 1 ml of cell suspension (1,5×109 CFU) of L. lactis pNZ::spike, pNZ::mini-spike or L. lactis pNZ::HA-spike was orally administered to Wistar rats. The same volume of peptone water was administered to the control group. Serum was collected from the animals at 28 days and IgG level was determined by ELISA for the quantitative determination of IgG antibodies to SARS-CoV-2 (COVID-19) Spike RBD protein in rat serum. As expected, the serum from control animals lacked antibodies to the RBD antigen. The serum of rats immunised once with cell suspension of the recombinant strains showed the following levels of specific IgG: 124,24±12,56 ng/ml in group pNZ::mini-spike, 165,91±59,13 ng/ml in group pNZ::spike, and 213,60±54,08 ng/ml in group pNZ::HA-spike. The highest IgG level (545,56±230,24 ng/ml) was detected in the serum of rats immunized with ultrasound-treated cell suspension of L. lactis pNZ::spike. No adverse effects were observed in vaccinated animals at regular check-ups throughout the study period.The current results have demonstrated that the RBD and full spike protein were successfully expressed in L. lactis. Oral administration of the recombinant L. lactis expressing S protein or RBD to rats appeared to generate the anti-SARS-CoV-2 antibodies in serum, positioning this bacteria as promising basis for creating oral vaccine.

A disposable, portable electrochemical immunosensor for rapid in situ detection of bovine tuberculosis

This contribution describes the development of a simple, fast, cost-effective, and sensitive impedimetric immunosensor for quantifying bovine tuberculosis (TB) in bovine serum samples. The construction of the immunosensor involved immobilizing the purified protein derivative (PPD) of M. bovis onto a screen-printed electrode that was modified with gold nanoparticles (AuNPs) and a polypyrrole (pPy) film synthesized electrochemically. The immunosensor exhibited a linear range from 0.5 μg mL−1 to 100 μg mL−1 and achieved a limit of detection (LD) of 100 ng mL−1 for the detection of anti-M. bovis antibody. The recovery percentages obtained in bovine serum samples were excellent, ranging between 98 % and 103 %.This device presents several advantages over alternative methods for determining TB in bovine serum samples. These include direct, in situ measurement without the need for pre-treatment, utilization of small volumes, thus avoiding harmful solvents and expensive reagents, and portability. In addition, the immunosensor exhibits both physical and chemical stability, retaining effectiveness even after 30 days of modification. This allows simultaneous incubations and facilitates large-scale detection.Hence, this immunosensor presents itself as a promising diagnostic tool for detecting anti-M. bovis antibodies in bovine serum. It serves as a viable alternative to tuberculin and ELISA tests.

Longevity of hybrid immunity against SARS-CoV-2 in adults vaccinated with an adenovirus-based COVID-19 vaccine

BackgroundHybrid immunity provides better protection against COVID-19 than vaccination or prior natural infection alone. It induces high magnitude and broadly cross-reactive neutralising anti-Spike IgG antibodies. However, it is not clear how long these potent antibodies last, especially in the context of adenovirus-based COVID-19 vaccines.MethodsWe conducted a longitudinal cohort study and enrolled 20 adults who had received an adenovirus-based COVID-19 vaccine before a laboratory-confirmed SARS-CoV-2 infection. We followed up the study participants for 390 days post the initial breakthrough infection. We assessed the longevity and cross-reactive breadth of serum antibodies against SARS-CoV-2 variants of concern (VOCs), including Omicron.ResultsThe binding anti-Spike IgG antibodies remained within the reported putative levels for at least 360 days and were cross-neutralising against Beta, Gamma, Delta, and Omicron. During the follow up period, a median of one SARS-CoV-2 re-infection event was observed across the cohort, but none resulted in severe COVID-19. Moreover, the re-exposure events were associated with augmented anti-Spike and anti-RBD IgG antibody titres.ConclusionsThis study confirms that hybrid immunity provides durable broadly cross-reactive antibody immunity against SARS-CoV-2 variants of concern for at least a year (360 days), and that it is further augment by SARS-CoV-2 re-exposure.

Rapid Decline of Mpox Antibody Responses Following MVA-BN Vaccination.

The replication-incompetent modified vaccinia Ankara-Bavarian Nordic vaccine (MVA-BN; Jynneos) was deployed during the 2022 clade IIb mpox outbreak. On August 14, 2024, the World Health Organization declared the mpox clade Ib outbreak in the Democratic Republic of the Congo a public health emergency of international concern, which has raised the question about the durability of vaccine immunity after MVA-BN vaccination. In this study, we show that the MVA-BN vaccine generated mpox serum antibody responses that largely waned after 6-12 months.

Influenza A Vaccine Candidates Based on Virus-like Particles Formed by Coat Proteins of Single-Stranded RNA Phages Beihai32 and PQ465.

Efficient control of influenza A infection can potentially be achieved through the development of broad-spectrum recombinant vaccines based on conserved antigens. The extracellular domain of the transmembrane protein M2 of influenza A virus (M2e) is highly conserved but poorly immunogenic and needs to be fused to an adjuvant protein or carrier virus-like particles (VLPs) to increase immunogenicity and provide protection against infection. In this study, we obtained VLPs based on capsid proteins (CPs) of single-stranded RNA phages Beihai32 and PQ465 bearing the M2e peptides. Four copies of the M2e peptide were linked to the C-terminus of the CP of phage Beihai32 and to the N and C termini of the CP of phage PQ465. The hybrid proteins, being expressed in Escherichia coli, formed spherical VLPs of about 30 nm in size. Immunogold transmission electron microscopy showed that VLPs formed by the phage PQ465 CP with a C-terminal M2e fusion present the M2e peptide on the surface. Subcutaneous immunization of mice with VLPs formed by both CPs containing four copies of the M2e peptide at the C termini induced high levels of M2e-specific IgG antibodies in serum and provided mice with protection against lethal influenza A virus challenge. In the case of an N-terminal fusion of M2e with the phage PQ465 CP, the immune response against M2e was significantly lower. CPs of phages Beihai32 and PQ465, containing four copies of the M2e peptide at their C termini, can be used to develop recombinant influenza A vaccine.

Immunization of cows with HIV envelope trimers generates broadly neutralizing antibodies to the V2-apex from the ultralong CDRH3 repertoire.

The generation of broadly neutralizing antibodies (bnAbs) to conserved epitopes on HIV Envelope (Env) is one of the cornerstones of HIV vaccine research. The animal models commonly used for HIV do not reliably produce a potent broadly neutralizing serum antibody response, with the exception of cows. Cows have previously produced a CD4 binding site response by homologous prime and boosting with a native-like Env trimer. In small animal models, other engineered immunogens were shown to focus antibody responses to the bnAb V2-apex region of Env. Here, we immunized two groups of cows (n = 4) with two regimens of V2-apex focusing Env immunogens to investigate whether antibody responses could be generated to the V2-apex on Env. Group 1 was immunized with chimpanzee simian immunodeficiency virus (SIV)-Env trimer that shares its V2-apex with HIV, followed by immunization with C108, a V2-apex focusing immunogen, and finally boosted with a cross-clade native-like trimer cocktail. Group 2 was immunized with HIV C108 Env trimer followed by the same HIV trimer cocktail as Group 1. Longitudinal serum analysis showed that one cow in each group developed serum neutralizing antibody responses to the V2-apex. Eight and 11 bnAbs were isolated from Group 1 and Group 2 cows, respectively, and showed moderate breadth and potency. Potent and broad responses in this study developed much later than previous cow immunizations that elicited CD4bs bnAbs responses and required several different immunogens. All isolated bnAbs were derived from the ultralong CDRH3 repertoire. The finding that cow antibodies can target more than one broadly neutralizing epitope on the HIV surface reveals the generality of elongated structures for the recognition of highly glycosylated proteins. The exclusive isolation of ultralong CDRH3 bnAbs, despite only comprising a small percent of the cow repertoire, suggests these antibodies outcompete the long and short CDRH3 antibodies during the bnAb response.

Effect of intravenous methylprednisolone on serum antibody levels in thyroid eye disease

Background/aimsWe evaluated longitudinal autoantibody changes after intravenous methylprednisolone (IVMP), compared them with those in untreated patients and identified prognostic factors for treatment response.MethodsIn this single-centre, retrospective, observational study, a total...

Diagnosis of viral infectious diseases through sensitive detection of human serum antibodies using a modified label-free electrochemical biosensor.

Rapid virus identification is crucial for preventing outbreaks. The COVID-19 pandemic has highlighted the critical nature of rapid virus detection. Here, we designed a label-free electrochemical biosensor modified with gold nanoparticles (AuNPs) to detect IgG antibodies from human serum, enabling rapid point-of-care diagnostics. AuNPs were synthesized and characterized. A multivariate optimization was carried out to determine the optimal condition for functionalizing AuNPs with anti-IgG. Subsequently, using a glassy carbon electrode (GCE), a modified AuNPs/GCE electrochemical biosensor was developed for IgG detection. The results indicated thatAuNPs displayed a spherical morphology with a size distribution of 19.54nm. Additionally, the zeta potential was recorded at -7.84mV. Central composite design (CCD) analysis determined the optimal conditions for functionalizing AuNPs to be an anti-IgG concentration of 320µgmL-1, atemperature of 25°C, and pH of 7.4. The characterization study confirmed the successful synthesis and functionalization of AuNPs. Through electrochemical impedance spectroscopy measurement, the biosensor demonstrated a limit of detection (LOD) of 0.2ngmL-1 and limit of quantification (LOQ) of 0.8ngmL-1. Furthermore, tests in real samples showed the interaction between IgG antibodies in serum samples and AuNPs/GCE, confirming the biosensor's ability to detect and quantify IgG in clinical samples.

Comprehensive Microbiological and Metagenomic Analysis of the Guillain–Barré Syndrome Outbreak in Lima, 2019

In 2018/2019, two large Guillain–Barré Syndrome (GBS) outbreaks took place in Peru. Here, we report a comprehensive analysis of biological samples from GBS patients from the 2019 outbreak. We applied metagenomic, microbiologic, and serological analyses to different biological samples collected from GBS patients. Further phenotypic and genomic characterization was conducted on Campylobacter jejuni isolates from GBS samples. Microbiologic and metagenomic analyses revealed several patients with multiple co-infections, yet no common infectious agents were found other than C. jejuni. Four C. jejuni isolates were isolated from rectal swabs. Twenty-one patients had detectable IgG serum antibodies related to C. jejuni, of whom seven had IgM antibodies. Genomic analyses showed that these four strains were clonal (ST2993) and contained the class A lipooligosaccharide biosynthesis locus. These results further support the idea that that C. jejuni is the etiological agent that triggered the GBS outbreak in Peru in 2019 and that the strains are not restricted to Peru, hence could be regarded as a broad public health concern. Furthermore, though we cannot delineate the role played by co-infections in GBS development, results obtained herein highlight metagenomic analysis as a potential new tool for depicting a yet unknown area of research in GBS.

Effect of advanced chelate technology-based trace minerals on growth performance, mineral digestibility, tibia properties, and antioxidant status in two broiler strains

This research aimed to assess the impact of diet supplementation of Advanced Chelate Technology-based Mineral (ACTMS), on the Ross and Arian broilers performance. 520 broilers, of two strains, were allocated to 8 treatments (4 for each strain), 5 replicates, (13 chicks/replicate) and reared for 42 days. The treatments include 0 (CONT), 250 (SBC250), 1000 (SBC1000), and 2000 (SBC2000) of ACTMS. Feed intake, weight gain, and feed conversion ratio were recorded, and the European Production Efficiency Factor (EPEF) was also calculated. Serum antibody was measured in response to sheep red blood cell (SRBC) to evaluate humoral immune response. Blood sample and tibia were used to measure the bone composition of Ca and P. No significant difference was obtained in feed intake (P >0.05), however, weight gain, feed conversion ratio, and EPEF showed significant differences (P˂0.05). The results showed that the interaction effect of Ross× SBC250 had the highest average daily feed intake during 25-42 and 0-42 days of age, but Ross×CONT group provided the lowest average daily feed intake (P˂0.05). Furthermore, the Ross×CONT group had the highest average daily gain during 0-10, 25-42, and 0-42 days of age (P<0.05). The Ross×CONT group also provided the best feed conversion ratio during 0-10 days of rearing period compared to other treatments (P<0.05). Various levels of ACTMS, significantly (P˂0.05) enhanced the antioxidant activity of superoxide dismutase and glutathione peroxidase. No significant differences were obtained in blood parameter (P>0.05), though, SBC2000 exhibited the greatest numerical phosphorus content. There was no significant impact of strain effects on blood metabolites, however, the Ross strain exhibited higher values. The results indicated that the Arian× SBC250 group had the largest tibia diameter which had a significant difference from the Arian×CONT group (P<0.05). In conclusion, ACTMS inclusion in the ration (either replacement or on top) led to the significant improvement of FCR and ADWG (SBC250 as on top) and EPEF (SBC2000 replacement) in the Ross strain and some parameters in Arian strains (mostly numerically).

Nanoparticle-Supported, Rapid, and Electronic Detection of SARS-CoV-2 Antibodies and Antigens at Attomolar Level.

A gold nanoparticle (AuNP)-supported rapid, electronic detection (NasRED) platform is demonstrated with high specificity to differentiate SARS-CoV-2 from human coronaviruses while achieving high sensitivity. Uniquely, active fluidic force is exerted on AuNPs in a microcentrifuge tube, through engineered centrifugation and vortex agitation, to accelerate signal transduction from biochemical protein binding to physical AuNP aggregation and precipitation and finally to electronic signals in a customized, stabilized circuitry. The limits of detection are found <80 aM (12 fg/mL) and ∼700 aM (105 fg/mL) to detect antibodies in human pooled serum and 20% diluted whole blood, and <900 aM (45 fg/mL) and 4.1 fM (200 fg/mL) to detect nucleocapsid proteins in human saliva and nasal fluid, respectively. With a small test volume (6 µL), a rapid turnaround time (as fast as <15 min), low reagent cost (estimated ∼$2), and a small system footprint, this novel digital platform can be utilized for accurate diagnosis and screening of a wide range of infectious and chronic diseases.

High serological and molecular prevalence of Ehrlichia canis and other vector-borne pathogens in dogs from Boa Vista Island, Cape Verde

Despite the high global impacts of canine vector-borne diseases (CVBD) due to their wide distribution and zoonotic potential, the current epidemiological situation of CVBD in many tropical and subtropical regions remains unknown. This study examines the seroprevalence and molecular prevalence of Ehrlichia canis and other pathogens causing CVBDs (Leishmania infantum, Dirofilaria immitis, Babesia spp., Anaplasma spp. and Hepatozoon canis) in dogs living on the island of Boa Vista (Cape Verde Republic). Blood samples and infesting ticks were taken from 150 dogs across the island (stray, shelter, and pet dogs). Serum samples were tested using a rapid immunochromatographic test (Uranotest® Quattro) that detects antibodies against E. canis, L. infantum, Anaplasma spp. and D. immitis antigen. Levels of serum antibodies against E. canis were measured using the immunofluorescence antibody test (IFAT). In addition, tick-borne pathogens in blood samples (Anaplasma spp., Babesia spp., Hepatozoon spp., and Ehrlichia canis) were detected by microscopy observation and/or PCR plus sequencing. The seroprevalence of E. canis was extremely high at 82% (123/150), as revealed by both immunochromatography and IFAT. Most dogs returning a seropositive test result (82.92%; 102/123) had antibody titres > 1:1280 but showed no clinical signs or notable laboratory abnormalities. Of the 123 animals testing seropositive for E. canis, 67 (54.47%) also presented antibodies against Anaplasma spp., and 13 (10.56%) showed the presence of Hepatozoon spp. gamonts in the blood smear. Ehrlichia canis infection was detected in 17.1% (25/146) of dogs tested by direct sequencing of polymerase chain reaction (PCR) products. Co-infections were detected in seven of these dogs: four dogs tested PCR-positive for both E. canis and A. platys, two dogs tested positive for E. canis and Hepatozoon spp., and one dog tested positive for E. canis, A. platys and Hepatozoon spp. Rhipicephalus sanguineus sensu lato was the only tick species found infesting the canine study population. The high prevalence of tick-borne pathogens detected in dogs from Boa Vista Island highlights a need for improved control measures designed to prevent the transmission of these pathogens.Graphical

Serum IgA antibody level against porcine epidemic diarrhea virus is a potential pre-evaluation indicator of immunization effects in sows during parturition under field conditions

BackgroundPorcine Epidemic Diarrhea (PED) is a highly contagious disease caused by Porcine Epidemic Diarrhea Virus (PEDV), resulting in a mortality rate of suckling piglets as high as 100%. Vaccination is the primary strategy for controlling PEDV infection, however, there is currently a lack of reliable methods for assessing the efficacy of vaccination. This study aimed to analyze serum and colostrum samples from 75 parturient sows with a specific vaccination strategy to measure levels of IgG, IgA, and neutralizing antibodies (nAbs) against PEDV, and to investigate the correlation between serum and colostrum antibody levels, as well as to identify potential biomarkers that can be used to evaluate immunization effects under field conditions.ResultsThe findings of correlation analysis between antibody levels of IgA, IgG, and nAbs in serum or colostrum samples revealed that IgG demonstrated the most robust correlation with nAbs exhibiting a correlation coefficient of 0.64 in serum samples. Conversely, IgA exhibited the highest correlation with nAbs, with a correlation coefficient of 0.47 in colostrum samples. Additionally, the correlation analysis of antibody levels between serum and colostrum samples indicated that serum IgA displayed the strongest correlation with colostrum IgA, with a coefficient of 0.63, indicating that serum IgA may serve as a viable alternative indicator for evaluating IgA levels in colostrum samples. To further evaluate the suitability of serum IgA as a substitute marker for colostrum IgA, levels of IgA antibodies in serum samples from sows were examined both pre- and post-parturition. The findings indicated that serum IgA levels were initially low prior to the initial immunization, experienced a notable rise 21 days after immunization, and maintained a significant elevation compared to pre-immunization levels from 21 days pre-parturition to 14 days postpartum, spanning a total of 35 days.ConclusionsSerum anti-PEDV IgA antibody levels may serve as a valuable predictor for immunization effects, allowing for the assessment of colostrum IgA antibody levels up to 21 days in advance. This insight could enable veterinarians to timely adjust or optimize immunization strategies prior to parturition, thereby ensuring adequate passive immunity is conferred to piglets through colostral transfer postpartum.

Solid-State Fermentation of Grain-Derived By-Products by Aspergillus kawachii and Rhizopus oryzae: Preparation and Evaluation of Anti-Allergic Activity

Grain processing produces many by-products, including wheat bran, wheat germ and rice bran, which are rich in carbohydrates, proteins and trace elements. In this study, these grain-derived by-products were used as raw materials to conduct solid-state fermentation using mixed strains of Aspergillus kawachii and Rhizopus oryzae, and the potential immunomodulatory and anti-allergic properties of fermented product were evaluated. Solid-state fermentation of a grain by-product mixture, consisting of rice bran, wheat bran, and wheat germ in a 2:1:1 weight ratio, using both A. kawachii L1 and R. oryzae L1 at 26 °C for 5 days, significantly increased the total phenolic, flavonoid, and amino acid contents. The anti-allergic activity of aqueous extract of the fermented product was evaluated in murine models of food allergy and delayed-type hypersensitivity. Oral administration of the fermented product extract (100–200 mg/kg) notably alleviated allergic symptoms such as diarrhea and histopathological changes in the intestines. Moreover, the extract effectively reduced allergen-specific serum antibodies, suppressed splenic cytokine secretion, and mitigated tissue edema and inflammation induced by allergens. Importantly, the extract induced the production of IL-10 and TGF-β, which are well-known cytokines primarily secreted by regulatory T cells. These results underscore the promising immunomodulatory effects of A. kawachii and R. oryzae fermented grain product, suggesting their potential as functional foods or additives for managing allergic disorders, with implications for future therapeutic and dietary applications.

Humoral immune response as an indicator for protection against Covid-19 after anti-SARS-COV2-booster vaccination in hematological and oncological patients.

Cancer patients are at a higher risk to develop severe COVID-19 symptoms after SARS-CoV-2 infection compared to the general population and regularly show an impaired immune response to SARS-CoV-2 vaccination. In our oncological center, 357 patients with hematological and oncological diseases were monitored for neutralizing antibodies from October 2021 over 12 months. All patients had received three anti-SARS-CoV-2 vaccinations with an mRNA-(Comirnaty/BionTech or Spikevax/Moderna) or a vector vaccine (Vakzevria/AstraZeneca or JCOVDEN/Johnson&Johnson). Neutralizing anti-SARS-CoV-2 IgG antibodies in the patients' sera were detected within 3 months before, 3-10 weeks and 5-7 months after the booster vaccination (third vaccination). 112 patients developed a breakthrough SARS-CoV-2 infection during the observation period. High anti-SARS-Cov-2 antibody levels before infection significantly protected against symptomatic Covid-19 disease (p = .003). The median antibody titer in patients with asymptomatic Covid-19 disease was 2080 BAU/ml (binding antibody units per Milliliter) and 765 BAU/ml in symptomatic patients. 98% of the solid tumor patients reached seroconversion after the booster vaccination in comparison to 79% of the hematological patients. High antibody titers of >2080 BAU/ml after the booster vaccination were detected in 61% of the oncological and 34.8% of the hematological patients. 7-10 months after the booster vaccination, the anti-SARS-CoV-2 antibody titer declined to an average of 849 BAU/ml. Considering the heterogenous humoral immune response of cancer patients observed in this study, an individual vaccination strategy based on regular measurement of anti-SARS-CoV-2 antibody levels should be considered in contrast to fixed vaccination intervals.

Antibodies Against ZSCAN1 in Pediatric and Adult Patients With Non-Paraneoplastic ROHHAD Syndrome.

To report the association of zinc finger and SCAN domain containing 1 antibodies (ZSCAN1-abs) with rapid-onset obesity, hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome in patients without tumor. Patients with symptoms compatible with ROHHAD syndrome but without an associated tumor were selected from our database. Serum and CSF samples were examined for the presence of ZSCAN1-abs by an in-house cell-based assay. In addition, samples from 149 patients with several inflammatory and noninflammatory disorders and 50 healthy participants served as controls. Thirteen patients with ROHHAD syndrome were identified. Of these, we had paired serum/CSF samples from 6 patients and only serum from the other 7. Five of 6 patients (83.3%) with paired serum/CSF (4 children, 1 adult) had ZSCAN-abs only in CSF and 1 had antibodies in serum and CSF. ZSCAN1-abs were not detected in the remaining 7 patients with ROHHAD with only serum available or in any of the 199 control samples. Patients with ROHHAD syndrome should be investigated for the presence of ZSCAN1-abs in CSF. The antibodies do not necessarily predict the presence of a tumor. The detection of ZSCAN1-abs in an adult patient suggests that this condition also occurs beyond the pediatric age.

Upper airway manifestations of anti-IgLON5 disease: Otorhinolaryngological point of view

IntroductionAnti-IgLON5 disease is a recently described neurological disorder with multisystemic features. The disease is characterized by the presence of IgLON5 antibodies in serum and cerebrospinal fluid. Our objective is to describe in detail the otorhinolaryngological manifestations of this disease, which are frequent and may include dysphagia, dysarthria, vocal cord paralysis and laryngospasm. MethodsIn this study, we present a series of 9 patients with anti-IgLON5 disease and otolaryngological manifestations. Patients were evaluated between July 2012 and March 2022 by video-polysomnography, fiber-optic laryngoscopy, and functional endoscopic evaluation of swallowing. ResultsThe median age was 71 years, and 5 (56%) were female. Video-polysomnography showed a NREM/REM parasomnia in 6 patients (67%), obstructive sleep apnea in 8 (88%), stridor during sleep in 7 (78%) and central apneas in 1 (11%). Six out of the 9 patients (67%) presented episodes of acute respiratory failure that required mechanical ventilation, 6 had vocal fold palsy with 4 of them requiring tracheostomy (3 had to be performed on an emergency basis). Dysphagia occurred in 8 patients (89%). Prominent upper airway secretion and sialorrhea was also present in 3 cases. ConclusionThe anti-IgLON5 disease exhibits extensive otolaryngological symptoms, mainly affecting the upper airway. These symptoms affect the quality of life and can be life-threatening. Prompt acute management is essential for stridor, dyspnea, and dysphagia. Given the potential severity of the symptoms and rarity of the disease, it is important for otolaryngologists to be familiar with anti-IgLON5 disease. Level of evidenceLevel 4.