Serum Titers Research Articles

Vaccination with inactivated virus against low pathogenic avian influenza subtype H9N2 does not prevent virus transmission in chickens

H9N2 subtype avian influenza has spread dramatically in China ever since first reported in the 1990s. A national vaccination program for poultry was initiated in 1998. Field isolation data show that the widely used inactivated H9N2 vaccine does not provide effective control of the transmission of this low pathogenic avian influenza (LPAI) virus in poultry. Current research has focused on two reasons: (i) insufficient immune response triggered by the vaccination with the inactivated virus, (ii) the occurrence of escape mutants selected by vaccine-induced immune pressure. However, the lack of effectivity of the inactivated virus vaccine to sufficiently reduce transmission has been noticed. We mimicked the natural infection and transmission process of the H9N2 virus in vaccinated and non-vaccinated chickens. A statistical model was used to estimate the transmission rate parameters among vaccinated chickens, varying in serum hemagglutinin inhibition titers (HIT) and non-vaccinated chickens. We demonstrate, for the first time, that the transmission is not sufficiently reduced by the H9N2 vaccine, even when vaccinated chickens have an IgG serum titer (HIT>23), which is considered protective for vaccination against homologous highly pathogenic avian influenza (HPAI) virus. Our study does, on the other hand, cast new light on virus transmission and immune escape of LPAI H9N2 virus in vaccinated chickens populations, and shows that new mitigation strategies against LPAI viruses in poultry are needed.

Efficacy of statistical process control procedures to identify deviations in continuously measured physiological and behavioral variables in beef heifers resulting from an experimentally combined viral-bacterial challenge.

The objective of this experiment was to determine if statistical process control (SPC) procedures coupled with remote continuous data collection could accurately differentiate between animals experimentally inoculated with a viral-bacterial (VB) challenge or phosphate buffer solution (PBS). Crossbred heifers (N = 38; BW = 230 ± 16.4 kg) were randomly assigned to treatments by initial weight, average daily gain (ADG), bovine herpes virus 1, and Mannheimia haemolytica serum titers. Feeding behavior, dry matter intake (DMI), animal activity, and rumen temperature were continuously monitored remotely prior to and following VB challenge. VB-challenged heifers exhibited decreased (P < 0.01) ADG and DMI, as well as increased (P < 0.01) neutrophils and rumen temperature consistent with a bovine respiratory disease (BRD) infection. However, none of the heifers displayed overt clinical signs of disease. Shewhart and cumulative summation (CUSUM) charts were evaluated, with sensitivity and specificity computed on the VB-challenged heifers (n = 19) and PBS-challenged heifers (n = 19), respectively, and the accuracy was determined as the average of sensitivity and specificity. To address the diurnal nature of rumen temperature responses, summary statistics (mean, minimum, and maximum) were computed for daily quartiles (6-h intervals), and these quartile temperature models were evaluated separately. In the Shewhart analysis, DMI was the most accurate (95%) at deciphering between PBS- and VB-challenged heifers, followed by rumen temperature (94%) collected in the 2nd and 3rd quartiles. Rest was most the accurate accelerometer-based traits (89%), and meal duration (87%) and bunk visit (BV) frequency (82%) were the most accurate feeding behavior traits. Rumen temperature collected in the 3rd quartile signaled the earliest (2.5 d) of all the variables monitored with the Shewhart, followed by BV frequency (2.8 d), meal duration (2.8 d), DMI (3.0 d), and rest (4.0 d). Rumen temperature and DMI remained the most accurate variables in the CUSUM at 80% and 79%, respectively. Meal duration (58%), BV frequency (71%), and rest (74%) were less accurate when monitored with the CUSUM analysis. Furthermore, signal day was greater for DMI, rumen temperature, and meal duration (4.4, 5.0, and 3.7 d, respectively) in the CUSUM compared to Shewhart analysis. These results indicate that Shewhart and CUSUM charts can effectively identify deviations in feeding behavior, activity, and rumen temperature patterns for the purpose of detecting sub-clinical BRD in beef cattle.

Універсальний метод очищення та концентрування вірусів на прикладі інноваційної розробки для парвовірусу гусей

A new method of purification and concentration of goose enteritis virus has been developed. For this purpose, three options for further purification of the virus were used and their comparative analysis was performed. The virus was purified without detergents, as well as with detergents – sarcosyl and nonide R-40. We obtained the best results using the mild nonionic detergent nonidet R-40, which was used in our further work. The virus was identified by electrophoretic studies in polyacrylamide gel, as well as electron microscopy. During purification and concentration of the virus, the infectious titer of the virus was 9.2-9.5 lg TCD50/cm3 suspension, in which the cell monolayer in 50% of the wells was affected by cytopathic action), which is 2 lg TCD50/cm3 higher than in the original material. The protein content in the test samples ranged from 200 to 500 mg/ ml. Thus, analyzing our results on the purification and concentration of goose enteritis virus, we can conclude that the antigen obtained by this method is suitable for the development of enzyme-linked immunosorbent assay (ELISA). Hyperimmune and negative sera for ELISA diagnostics were obtained, the optimal ratios of components for designing an ELISA test system were worked out, and the formula for recalculating antibody titers in geese blood sera when testing them in one dilution was derived. A positive-negative threshold was determined for this diagnosticum (which of the studied sera have a positive, doubtful or negative titer of antibodies to the causative agent of viral enteritis in geese). In the new conditions the spread of particularly dangerous viruses, this development, with the appropriate equipment, can be further used to purify and concentrate these viruses, study their biological properties, cultivate and use them in the development of new vaccines.

Primary Anetoderma and Acquired Cutis Laxa Associated with Glomerulonephritis in a 37-year-old Filipino Male: A Case Report

A 37-year-old Filipino man presented with a 9-month history of sagging skin progressing cephalocaudally from the chin and neck to the axillae, side of the trunk, and pelvic area. This was followed by a 2-month history of increasing serum creatinine levels associated with periorbital and bipedal edema, generalized weakness, decreased appetite, vomiting, and headache. Subsequently, skin-colored, non-tender sac-like plaques appeared on the abdomen, inguinal, and intergluteal areas. Histopathology of the latter lesions showed increased spaces between collagen bundles in the dermis. Staining with Verhoeff-van Gieson revealed focal sparse elastic fibers in the papillary dermis compared to that of the reticular dermis consistent with anetoderma. Further work-up revealed normal ANA titer and low serum C3. Kidney biopsy showed IgG deposition in the tubular basement membrane and trace C3 deposition in the glomerular mesangium, giving a diagnosis of rapid progressive glomerulonephritis. On subsequent follow-up, the sac-like plaques became lax and presented as generalized wrinkling of the skin, raising the question whether cutis laxa and anetoderma are occurring in a spectrum instead as distinct entities. Based on the current review of literature, this is the first reported case of primary anetoderma co-occurring with cutis laxa in a patient with glomerulonephritis. Deposition of immunoglobulins along the elastic fibers could have activated the complement system, mediating the destruction of the elastic fibers, resulting to cutis laxa and anetoderma. This case also considers the possibility of anetoderma and type I acquired cutis laxa occurring either in a spectrum or as distinct diseases in a single patient. Further investigations may identify an ultrastructural pattern that can help differentiate the two entities.

Development of a microneutralization assay for HSV-2

BackgroundPlaque Reduction Neutralization Test (PRNT) is the standard assay used for measuring neutralizing antibody responses to Herpes simplex virus type-2 (HSV-2). The PRNT is a cumbersome, time-consuming and laborious assay. The development of a faster, high throughput microneutralization assay (MNA) for HSV-2 viruses carried out in a 96-well format will allow for rapid testing of large numbers of samples for drug and vaccine development. MethodsWe describe the generation of a MNA that utilizes a pair of anti-HSV human monoclonal antibodies (mAbs) for virus detection in HSV-2 infected Vero cells. Antibodies were generated by B-cell cloning from PBMC’s isolated from HSV-1 negative/HSV-2 positive donors. We describe the selection and characterization of the antibodies used for virus detection by ELISA with purified, recombinant anti-HSV glycoproteins, antibody binding in infected cells, and Western Blot. We determine the anti-HSV-2 neutralizing titers of immune sera from mice by MNA and PRNT and compare these results by linear regression analysis. ResultsWe show that neutralization titers for HSV-2, determined by the 96-well MNA correlate with titers determined by a PRNT completed in 24-well plates in both the absence (R2 = 0.8250) and presence (R2 = 0.7075) of complement. ConclusionsWe have successfully developed an MNA that can be used in place of the burdensome PRNT to determine anti-HSV-2 neutralizing activity in serum. This MNA has much greater throughput than the PRNT, allowing many more samples to be processed in a shorter time saving ∼90 % of the time required by the laboratory scientist to complete the task as compared to the traditional PRNT.

Inflammasome Activity in Response to Influenza Vaccination Is Maintained in Monocyte-Derived Peripheral Blood Macrophages in Older Adults.

Introduction: Each year, a disproportionate number of the total seasonal influenza-related hospitalizations (90%) and deaths (70%) occur among adults who are >65 years old. Inflammasome activation has been shown to be important for protection against influenza infection in animal models but has not yet been demonstrated in humans. We hypothesized that age-related dysfunction (immunosenescence) of the inflammasome may be associated with poor influenza-vaccine response among older adults. Methods: A cohort of younger (18–40 years of age) and older (≥65 years of age) adults was recruited prior to the 2014–2015 influenza season. We measured hemagglutination inhibition (HAI) titers in serum before and 28 days after receipt of the seasonal inactivated influenza vaccine. Inflammasome-related gene expression and protein secretion were quantified in monocyte-derived macrophages following stimulation with influenza A/H1N1 virus. Results: Younger adults exhibited higher HAI titers compared to older adults following vaccination, although inflammasome-related protein secretion in response to influenza stimulation was similar between the age groups. Expression of P2RX7 following influenza stimulation was lower among older adults. Interestingly, CFLAR expression was significantly higher among females (p = 2.42 × 10−5) following influenza stimulation and this gene may play an important role in the development of higher HAI antibody titers among older females. Conclusion: Inflammasome activation in response to influenza vaccination appears to be maintained in monocyte-derived macrophages from older adults and does not explain the poor influenza vaccine responses generally observed among this age group.

The impact of spike N501Y mutation on neutralizing activity and RBD binding of SARS-CoV-2 convalescent serum.

BackgroundSeveral SARS-CoV-2 lineages with spike receptor binding domain (RBD) N501Y mutation have spread globally. We evaluated the impact of N501Y on neutralizing activity of COVID-19 convalescent sera and on anti-RBD IgG assays.MethodsThe susceptibility to neutralization by COVID-19 patients’ convalescent sera from Hong Kong were compared between two SARS-CoV-2 isolates (B117-1/B117-2) from the α variant with N501Y and 4 non-N501Y isolates. The effect of N501Y on antibody binding was assessed. The performance of commercially-available IgG assays was determined for patients infected with N501Y variants.FindingsThe microneutralization antibody (MN) titers of convalescent sera from 9 recovered COVID-19 patients against B117-1 (geometric mean titer[GMT],80; 95% CI, 47–136) were similar to those against the non-N501Y viruses. However, MN titer of these serum against B117-2 (GMT, 20; 95% CI, 11–36) was statistically significantly reduced when compared with non-N501Y viruses (P < 0.01; one-way ANOVA). The difference between B117-1 and B117-2 was confirmed by testing 60 additional convalescent sera. B117-1 and B117-2 differ by only 3 amino acids (nsp2-S512Y, nsp13-K460R, spike-A1056V). Enzyme immunoassay using 272 convalescent sera showed reduced binding of anti-RBD IgG to N501Y or N501Y-E484K-K417N when compared with that of wild-type RBD (mean difference: 0.1116 and 0.5613, respectively; one-way ANOVA). Of 7 anti-N-IgG positive sera from patients infected with N501Y variants (collected 9-14 days post symptom onset), 6 (85.7%) tested negative for a commercially-available anti-S1-IgG assay.InterpretationWe highlighted the importance of using a panel of viruses within the same lineage to determine the impact of virus variants on neutralization. Furthermore, clinicians should be aware of the potential reduced sensitivity of anti-RBD IgG assays.

Role of Leptospira spp. testing and ocular examination in horses with equine recurrent uveitis: A retrospective study of 63 horses

SummaryBackgroundThere is little information on the correlation between equine recurrent uveitis (ERU) and leptospiral infection status as it relates to ocular examination findings and testing recommendations.ObjectiveTo evaluate the role of leptospiral testing in horses with ERU by correlating results to signalment, clinical findings and visual outcome.Study designRetrospective case series.MethodsRecords of horses presenting for ERU at NC State University Veterinary Health Complex (NCSU‐VHC) between 2014 and 2019 were reviewed. Signalment, initial visual status, ocular examination findings, treatments and visual outcome were collected. Serum and aqueous humour (AH) leptospiral titres were assessed for six different leptospirosis serovars and polymerase chain reaction (PCR) testing. Goldmann‐Whitmer (C) values were calculated.ResultsRecords of 63 horses and 78 eyes with ERU were evaluated. Horses with a positive aqueous humour PCR were significantly younger in age (mean 9.25 ± 1.14) than PCR negative horses (mean 13.3 ± 0.95) (p = 0.01). A positive aqueous humour titre of any serotype was significantly correlated to blindness at presentation (p = 0.04). A positive serum titre was significantly correlated to presence of ocular posterior segment disease (p = 0.01). Positivity to L. bratislava in the serum correlated to posterior segment disease (p = 0.04) and AH positivity correlated to blindness at presentation (p = 0.002).Main limitationsLimitations of this study include that it is a retrospective and information gathered relies on data included within medical records.ConclusionsPositive leptospiral testing results were associated with younger horses and ocular posterior segment clinical disease. Horses with aqueous humour titres to any leptospiral serotype, especially L. bratislava serovar, were correlated to poor prognosis for vision.

Favorable antibody responses to human coronaviruses in children and adolescents with autoimmune rheumatic diseases

BackgroundDifferences in humoral immunity to coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), between children and adults remain unexplained, and the effect of underlying immune dysfunction or suppression is unknown. Here, we sought to examine the antibody immune competence of children and adolescents with prevalent inflammatory rheumatic diseases, juvenile idiopathic arthritis (JIA), juvenile dermatomyositis (JDM), and juvenile systemic lupus erythematosus (JSLE) against the seasonal human coronavirus (HCoV)-OC43 that frequently infects this age group.MethodsSera were collected from JIA (n = 118), JDM (n = 49), and JSLE (n = 30) patients and from healthy control (n = 54) children and adolescents prior to the coronavirus disease 19 (COVID-19) pandemic. We used sensitive flow-cytometry-based assays to determine titers of antibodies that reacted with the spike and nucleoprotein of HCoV-OC43 and cross-reacted with the spike and nucleoprotein of SARS-CoV-2, and we compared them with respective titers in sera from patients with multisystem inflammatory syndrome in children and adolescents (MIS-C).FindingsDespite immune dysfunction and immunosuppressive treatment, JIA, JDM, and JSLE patients maintained comparable or stronger humoral responses than healthier peers, which was dominated by immunoglobulin G (IgG) antibodies to HCoV-OC43 spike, and harbored IgG antibodies that cross-reacted with SARS-CoV-2 spike. In contrast, responses to HCoV-OC43 and SARS-CoV-2 nucleoproteins exhibited delayed age-dependent class-switching and were not elevated in JIA, JDM, and JSLE patients, which argues against increased exposure.ConclusionsConsequently, autoimmune rheumatic diseases and their treatment were associated with a favorable ratio of spike to nucleoprotein antibodies.FundingThis work was supported by a Centre of Excellence Centre for Adolescent Rheumatology Versus Arthritis grant, 21593, UKRI funding reference MR/R013926/1, the Great Ormond Street Children’s Charity, Cure JM Foundation, Myositis UK, Lupus UK, and the NIHR Biomedical Research Centres at GOSH and UCLH. This work was supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK, the UK Medical Research Council, and the Wellcome Trust.

A large repertoire of B cell lineages targeting one cluster of epitopes in a vaccinated rhesus macaque

The repertoire of antibodies (Abs) produced upon vaccination against a particular antigenic site is rarely studied due to the complexity of the immunogens. We received such an opportunity when one rhesus macaque was immunized six times at 0, 4, 10, 16, 32, and 143 weeks with C4-447 peptide containing the 8-mer epitope for human monoclonal Ab (mAb) 447-52D specific to the V3 region of gp120 HIV-1. Strong anti-V3 antibody responses reached 50% binding titer in serum of 10−5 at week 10 that declined to 10−3 by week 70. After an additional boost of C4-447 peptide at week 143, titers rebounded to 10−5 at week 146, or 2.7 years after the first immunization. Using the blood sample at week 146, we produced 41 V3-specific recombinant mAbs by single B cell isolation and cloning. Sequence analysis revealed 21B cell lineages, single and clonally related, based on immunoglobulin gene usage and CDR3s. The broad repertoire of Abs directed to a small antigenic site shows the targeting potency of a vaccine-elicited immune response in rhesus macaques.

Intramuscular vs. Intradermic Needle-Free Vaccination in Piglets: Relevance for Animal Welfare Based on an Aversion Learning Test and Vocalizations.

The aim of the present study was to compare intramuscular injection with a needle and intradermic needle-free vaccinations against porcine reproductive and respiratory syndrome (PRRS) in piglets at 28 days old by studying behavioral and physiological reactions. A total of 72 piglets divided into 2 sex-balanced batches were assessed. Within each batch, the piglets were divided into three treatments, which were Hipradermic (0.2 ml of UNISTRAIN® PRRS vaccine administered with an intradermic needle-free device), Intramuscular (IM, 2.0 ml of vaccine), and Control (not vaccinated). Before the vaccination, the piglets were trained to cross a 4-m-long raceway to perform an aversion learning test. The day of vaccination, the time taken to cross the raceway was registered for each piglet at different times: prior to the vaccination and 10 min, 2, 24, 48, and 72 h after the vaccination, to measure variations in these times as signs of aversion to the vaccination process. Vocalizations, as potential signs of pain, were recorded as well at the end of this raceway to analyze their frequency (Hz), duration, and level of pressure (dB) at the moment of vaccination. Salivary cortisol, as a sign of the HPA-axis activity, was assessed 10 min after the vaccination. In addition, activity budgets, local reaction to the vaccine, and serological titer were also considered in the study. Ten minutes after the vaccination, the IM piglets took longer (p < 0.001) to cross the raceway than did the Hipradermic and Control piglets. Vocalizations were significantly different between the three treatments: the Control piglets produced vocalizations with the lowest frequency (p < 0.001) and level of pressure (p < 0.001), and IM with the highest, with Hipradermic in a significant intermediate position (p < 0.001). Accordingly, the day of the vaccination, IM and Hipradermic animals were lying on the side of the vaccine administration a greater proportion of time than were the Control piglets (10, 11, and 6%, respectively; p = 0.027). Salivary cortisol was not significantly different between treatments. The serum titer of antibodies against the PRRS was higher (p < 0.001) in both vaccinated treatments in comparison to the Control piglets. It is concluded that the Hipradermic needle-free vaccination may result in a less aversive experience in piglets than did intramuscular vaccination.

Walking down the memory lane with SARS-CoV-2 B cells.

The B-cell response to COVID-19 vaccines in convalescent individuals.

Immunological and functional features of decellularized xenogeneic heart valves after transplantation into GGTA1-KO pigs.

Decellularization of xenogeneic heart valves might lead to excellent regenerative implants, from which many patients could benefit. However, this material carries various xenogeneic epitopes and thus bears a considerable inherent immunological risk. Here, we investigated the regenerative and immunogenic potential of xenogeneic decellularized heart valve implants using pigs deficient for the galactosyltransferase gene (GGTA1-KO) as novel large animal model. Decellularized aortic and pulmonary heart valves obtained from sheep, wild-type pigs or GGTA1-KO pigs were implanted into GGTA1-KO pigs for 3, or 6 months, respectively. Explants were analyzed histologically, immunhistologically (CD3, CD21 and CD172a) and anti-αGal antibody serum titers were determined by ELISA. Xenogeneic sheep derived implants exhibited a strong immune reaction upon implantation into GGTA1-KO pigs, characterized by massive inflammatory cells infiltrates, presence of foreign body giant cells, a dramatic increase of anti-αGal antibody titers and ultimately destruction of the graft, whereas wild-type porcine grafts induced only a mild reaction in GGTA1-KO pigs. Allogeneic implants, wild-type/wild-type and GGTA1-KO/GGTA1-KO valves did not induce a measurable immune reaction. Thus, GGTA1-KO pigs developed a 'human-like' immune response toward decellularized xenogeneic implants showing that immunogenicity of xenogeneic implants is not sufficiently reduced by decellularization, which detracts from their regenerative potential.

Development and Comparison of a Panel of Modified CS17 Fimbrial Tip Adhesin Proteins as Components for an Adhesin-Based Vaccine against Enterotoxigenic Escherichia coli.

Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrhea in travelers and children in resource-limited countries. ETEC colonization factors, fimbrial tip adhesins and enterotoxins are key virulence factors, and thus have been studied as vaccine candidates. Some prevalent colonization factors, including CFA/I and CS17, belong to the class 5 family. We previously found that passive oral administration of hyperimmune bovine colostral IgG (bIgG) raised against dscCfaE (donor strand complemented CFA/I tip adhesin) protected volunteers against CFA/I+ ETEC challenge, while anti-dscCsbD bIgG (CS17 tip adhesin) did not confer protection. These findings led us to develop and optimize a panel of alternative CsbD-based vaccine candidates based on allele matching and in silico protein engineering. Physicochemical characterizations revealed that an optimized vaccine candidate dscCsbDLSN139(P218A/G3) had the greatest thermal stability among the six tested dscCsbD adhesins, whereas the overall secondary structures and solubility of these adhesins had no obvious differences. Importantly, dscCsbDLSN139(P218A/G3) elicited significantly higher CS17+ ETEC hemagglutination inhibition titers in sera from mice intranasally immunized with the panel of dscCsbD adhesins, while no significant difference was observed among heterologous neutralizing titers. Our results strongly advocate for the incorporation of these modifications into a new generation of CsbD-based ETEC vaccine candidates.

Highly feasible immunoprotective multicistronic SARS-CoV-2 vaccine candidate blending novel eukaryotic expression and Salmonella bactofection

IntroductionThe emergence of SARS-CoV-2 variants has raised concerns on future vaccine efficacy as most vaccines target only the spike protein. Hence, vaccines targeting multiple SARS-CoV-2 proteins will offer broader protection and improve our preparedness to combat the pandemic. ObjectivesThe study aimed to develop a novel vaccine strategy by combining a eukaryotic vector expressing multiple SARS-CoV-2 genes and Salmonella-mediated in vivo DNA delivery. MethodsThe eukaryotic vector was designed to function as a DNA-launched RNA replicon in a self-replicating and self-amplifying mRNA mechanism. By exploiting the self-cleaving peptide, P2A, we fused four SARS-CoV-2 targets, including receptor-binding domain (RBD), heptad repeat domain (HR), membrane protein (M) and epitopes of nsp13, in a single open reading frame. Western blot and immunofluorescence assays were used to determine protein expression. In mice, the vaccine's safety and immunogenicity were investigated. ResultsWestern blot analysis revealed co-expression all four proteins from the vaccine construct, confirming the efficiency of Salmonella-mediated gene delivery and protein expression. The vaccine candidate was safe and elicited robust antigen-specific antibody titers in mice, and a recall response from splenocytes revealed induction of strong cell-mediated immunity. Flow cytometry demonstrated an increase in sub-populations of CD4+ and CD8+ T cells with the highest CD4+ and CD8+ T cells recorded for HR and RBD, respectively. Overall, humoral and cellular immune response data suggested the induction of both Th1 and Th2 immunity with polarization towards an antiviral Th1 response. We recorded a potent SARS-CoV-2 neutralizing antibody titers in the immunized mice sera. ConclusionsThe Salmonella bactofection ensured optimum in vivo gene delivery, and through a P2A-enabled efficient multicistronic expression, the vaccine candidate elicited potent anti-SARS-CoV-2 immune responses. These findings provide important insight into development of an effective multivalent vaccine to combat SARS-CoV-2 and its variants.

Do modified live virus vaccines against bovine viral diarrhea induce fetal cross-protection against HoBi-like Pestivirus?

Bovine Pestivirus heterogeneity is a major challenge for vaccines against bovine viral diarrhea (BVD). In breeding herds, fetal protection is a high priority issue. To some degree, fetal infections in vaccinated heifers have been attributed to the antigenic diversity of bovine Pestiviruses. The purpose of this study was to assess fetal protection against a divergent bovine Pestivirus (Hobi-like Pestivirus, HoBiPeV) with a commercially available modified live vaccine (MLV) claiming fetal protection against BVDV 1 and BVDV 2 up to one year after the first inoculation. Five vaccinated and four unvaccinated heifers were challenged by intranasal inoculation with the HoBiPeV Italy-1/10-1 strain between 82 and 89 days after insemination, i.e. between 4 and 6 months after vaccination. At challenge, neutralizing antibody titers to HoBiPeV in vaccinated heifers were low or even undetectable. Of the four unvaccinated heifers, one control animal aborted (fetus not available) and the remaining three gave birth to HoBiPeV positive calves. Among the heifers of the vaccinated group, one aborted the fetus in the sixth month of pregnancy, which tested Pestivirus negative, while three others gave birth to healthy, HoBiPeV negative calves; the remaining heifer delivered one HoBiPeV positive calf. The results suggest that the BVDV vaccine might be able to elicit a partial fetal protection against HobiPeV, even in absence of a strong specific antibody response.

Incidence of SARS-CoV-2 infection in health care workers from Northern Italy based on antibody status: immune protection from secondary infection- A retrospective observational case-controlled study

ObjectiveThe protection from SARS-CoV-2 infection induced by SARS-CoV-2 anti-S1 and anti-S2 IgG antibody positivity resulting from natural infection was evaluated. MethodsThe frequency of SARS-CoV-2 infection (as determined by virus RNA detection) was evaluated in a group of 1,460 seropositive and a control group of 8,150 seronegative healthcare workers in three Centres of Northern Italy in the period June-November 2020. Neutralizing serum titers were analyzed in seropositive subjects with or without secondary SARS-CoV-2 infection. ResultsDuring the 6-month survey, 1.78% seropositive subjects developed secondary SARS-CoV-2 infection while 6.63% seronegative controls developed primary infection (odds ratio: 0.26; 95% confidence interval: 0.17-0.38). Secondary infection was associated with low or absent serum neutralizing titer (p<0.01) and was mildly symptomatic in 45.8% cases vs 71.4% symptomatic primary infections (odds ratio: 0.34; 95% confidence interval: 0.16-0.78). ConclusionsImmunity from natural infection appears protective from secondary infection; therefore, vaccination of seronegative subjects might be prioritized.

Anti-GABA-B receptor encephalitis with small cell lung cancer presenting with septic shock during immunotherapy

Abstract Introduction: Most patients with anti-γ-aminobutyric acid-B (anti-GABA-B) receptor encephalitis present with cancer and have a poor response to immunotherapy. Moreover, septic shock, a subset of sepsis, is rarely reported in these patients during immunotherapy. Patient concerns: A 55-year-old man presented with epileptic seizure and cognitive impairment. He was previously healthy and had no family history of psychiatric disorders but had a history of smoking and emphysema. Diagnoses: Combined with the symptoms and antibody testing, anti-GABA-B encephalitis with anti-Hu antibody was diagnosed. During immunotherapy, he presented with septic shock. Further investigations and pathological examination confirmed the diagnosis of small cell lung cancer. Interventions: The patient was treated with five days of intravenous immunoglobulin (0.4/kg/d), ten days of methylprednisolone (1.0 g once a day and half the dose every three days), plus ten days of oxycarbazepine (0.3 g b.i.d.) and magnesium valproate (0.25 g b.i.d.). He received nine days of conventional treatment for septic shock in addition to meropenem (1 g intravenously every 8 hours) and etimicin (0.3 g intravenously per day). After that, he received one month of prednisone 30 mg with dose reduction 5 mg every two weeks, oxcarbazepine 0.3 g b.i.d. and valproic acid 0.25 g b.i.d. for antiepileptic treatment, olanzapine 5 mg qd + qn for antipsychotic symptoms. Outcomes: He was able to communicate with others normally and also had improved memory and clear thinking. Mini-Mental State Examination and Modified Rankin Scale were 23/30 and 1. At discharge, the titer of anti-GABA-B receptor antibody in serum (1:10) was significantly lower than the titer in serum on the day of admission (1: 100). Conclusion: Anti-GABA-B receptor encephalitis patients with cancer can respond well to immunotherapy. Personalized treatment should be considered to avoid complications like septic shock in anti-GABA-B receptor encephalitis with cancer during immunotherapy.

Immunization with Pneumocystis carinii A121\u201385 antigen activates immune function against P. carinii

BackgroundPneumocystis pneumonia (PcP), which is caused by Pneumocystis carinii, is a life-threatening infection that affects immunocompromised individuals. Unfortunately, chemoprophylaxis and dapsone are only effective for half of the patients with PcP, indicating that additional preventive methods are needed. We predicated the pneumocystis surface protein A12 sequence 1–85 by DNAStar software and BepiPred, and identified it as a potential vaccine candidate by bioresearch.MethodsWe used recombinant A121–85 as antigen to immunized mice and detected serum titer of IgG, expression of inflammatory factors by EILSA, qRT-PCR and flow cytometry.ResultsOur results showed that immunization with recombinant A121–85 increased the serum titer of IgG, promoted the secretion of T lymphocytes, increased the expression of inflammatory factors, and elevated lung inflammatory injury in mice.ConclusionsOur findings suggest that A121–85 is a potential vaccine target for preventing Pneumocystis carinii. The evaluation of A121–85-elicited antibodies in the prevention of PcP in humans deserves further investigation.

Тест-система ІФА для метапневмовірусної інфекції птиці: методологія розробки та використання у ветеринарній практиці

In the absence of diagnostic kits for the detection of antibodies to metapneumovirus infection (MPVI) epizootological monitoring in Ukrainian farms is practically not carried out, imported test systems have a "sky-high" price, so there is a need for domestic methods of diagnosing this disease. The most accurate, easy-to-use method is ELISA-based test systems (enzyme-linked immunosorbent assay). A diagnostic ELISA test system for the detection of antibodies to MPVI has been developed and it has been established that this diagnosticum should be used in the practice of veterinary medicine for serological control of metaviral virus infection. The optimal ratios of components for the manufacture of ELISA test system have been worked out. The form of calculation of antibody titers in blood sera of chickens when testing them in one dilution is calculated. The sensitivity and specificity of the ELISA test system were determined (comparative analysis of serum testing results in ELISA, RNGA and RN). Scientific documentation has been developed – instructions for the manufacture and control of ELISA test systems for the detection of antibodies to metapneumovirus infection in the serum of chickens and instructions for its use. Indication and identification of the obtained virus isolate was carried out using polymerase chain reaction (PCR) and nucleotide sequencing. Based on the studies carried out in the suspension of the internal organs of turkeys (trachea, lungs), a virus belonging to subtype B of the genus Metapneumovirus, subfamily Pneumovirinae, family Paramyxoviridae of the order Mononegavirales was revealed. By comparing the nucleotide sequence of the G gene fragment of the PVT-09/B strain with the sequences of strains and isolates of the avian metapneumovirus subtype B published in the GenBank database, it was found that the metapneumovirus isolated from sick turkeys is phylogenetically close to the Brazilian strains 27A-07 2007 and MPV/B/Brazil-07/USP-08 G