Non-immunized Group Research Articles

Shedding reduction and immunity modulation in piglets with an inactivated Mycoplasma hyopneumoniae vaccine encapsulated in nanostructured SBA-15 silica

Mycoplasma (M.) hyopneumoniae is a primary etiological agent of porcine enzootic pneumonia (PEP), a disease that causes significant economic losses to pig farming worldwide. Current commercial M. hyopneumoniae vaccines induce partial protection, decline in preventing transmission of this pathogen or inducing complete immunity, evidencing the need for improving vaccines against PEP. In our study, we aimed to test the effectiveness of the SBA-15 ordered mesoporous silica nanostructured particles as an immune adjuvant of a vaccine composed of M. hyopneumoniae strain 232 proteins encapsulated in SBA-15 and administered by intramuscular route in piglets to evaluate the immune responses and immune-protection against challenge. Forty-eight 24-day-old M. hyopneumoniae-free piglets were divided into four experimental groups with different protocols, encompassing a commercial vaccine against M. hyopneumoniae, SBA-15 vaccine, SBA-15 adjuvant without antigens and a non-immunized group. All piglets were challenged with the virulent strain 232 of M. hyopneumoniae. Piglets that received the SBA-15 and commercial vaccine presented marked immune responses characterized by anti-M. hyopneumoniae IgA and IgG antibodies in serum, anti-M. hyopneumoniae IgA antibodies in nasal mucosa and showed an upregulation of IL-17 and IL-4 cytokines and downregulation of IFN-γ in lungs 35 days post-infection. Piglets immunized with SBA-15 vaccine presented a reduction of bacterial shedding compared to piglets immunized with a commercial bacterin. In addition, piglets from SBA-15 adjuvant suspension group presented increased IL-17 gene expression in the lungs without involvement of Th1 and Th2 responses after challenge. These results indicated that SBA-15 vaccine induced both humoral and cell-mediated responses in the upper respiratory tract and lungs, first site of replication and provided protection against M. hyopneumoniae infection with a homologous strain with reduction of lung lesions and bacterial shedding. Finally, these results enhance the potential use of new technologies such as nanostructured particles applied in vaccines for the pig farming industry.

Assessment of effectiveness and impact of universal prophylaxis with nirsevimab for prevention of hospitalizations due to respiratory syncytial virus in infants. The NIRSE-GAL study protocol

ABSTRACT Nirsevimab has been recently licensed for universal RSV prophylaxis in infants. NIRSE-GAL is a three-year population-based study initiated in Galicia in September 2023. It aims to evaluate nirsevimab effectiveness against RSV-related hospitalizations lower respiratory tract infections (LRTI), severe RSV, all-cause LRTI, and all-cause hospitalization. NIRSE-GAL also aims to estimate nirsevimab impact on primary healthcare use in the short and mid-term, children’s wheezing and asthma, and medical prescriptions for RSV. The immunization campaigns will be scheduled based on the expected start week for the RSV season and will last the whole season. Immunization will be offered to: i) infants born during the campaign (seasonal), ii) infants < 6 months at the start of the campaign (catch-up), and iii) infants with high-risk factors, aged 6–24 months at the start of the campaign (high-risk). The follow-up period will start: i) the immunization date for all immunized infants, ii) the start of the campaign, for the non-immunized catch-up or high-risk groups, or iii) the birthdate for the non-immunized seasonal group. Infants will be followed up until outcome occurrence, death, or end of study. Nirsevimab effectiveness will be estimated using Poisson and Cox regression models. Sensitivity and stratified analyses will be undertaken. The number of averted cases and the number needed to immunize will be estimated. Immunization failure and nirsevimab safety will be monitored. NIRSE-GAL was approved by the ethics committee of Galicia (CEIC 2023–377) and registered in ClinicalTrials.gov (ID: NCT06180993). Findings will be mainly shared via peer-reviewed publications and scientific conferences.

Hematological parameters to predict post-COVID-19 immune response among vaccinated and non-vaccinated individuals: A retrospective cross-sectional study

Background: This study finds the changes in the hematological parameters of healthy individuals to predict the immune status against COVID-19 among COVID -19 vaccinated and non-vaccinated individuals. Methods: A comparative cross-sectional study among 210 healthy individuals was conducted. All individuals were divided into three groups, i.e IgG positive, IgG negative, and IgG and IgM positive, based on ELISA. Data analysis was done using SPSS version 25 for Windows. Results: A statistically significant effect was found among the three groups in terms of mean levels of hemoglobin (Hb), hematocrit (Hct), mean corpuscular hemoglobin concentration (MCHC), red blood cells (RBC), RDW-CV, lymphocyte, neutrophil, eosinophils, and basophil count. The study also showed that 52.8% (n=74) had neither taken vaccination nor had any history of previous COVID-19 infection but were IgG antibody positive. Conclusion: There was a statistically significant difference among hematological parameters between immune and nonimmune groups, and it can predict the COVID-19 immune status.

Intranasal administration of Escherichia coli Nissle expressing the spike protein of SARS-CoV-2 induces long-term immunization and prevents spike protein-mediated lung injury in mice

While current anti-Spike protein (SP) vaccines have been pivotal in managing the pandemic, their limitations in delivery, storage, and the inability to provide mucosal immunization (preventing infections) highlight the ongoing necessity for research and innovation. To tackle these constraints, our research group developed a bacterial-based vaccine using a non-pathogenic E. coli Nissle 1917 (EcN) strain genetically modified to express the SARS-CoV-2 spike protein on its surface (EcN-pAIDA1-SP). We intranasally delivered the EcN-pAIDA1-SP in two doses and checked specific IgG/IgA production as well as the key immune mediators involved in the process. Moreover, following the initial and booster vaccine doses, we exposed both immunized and non-immunized mice to intranasal delivery of SARS-CoV-2 SP to assess the effectiveness of EcN-pAIDA1-SP in protecting lung tissue from the inflammation damage. We observed detectable levels of anti-SARS-CoV-2 spike IgG in serum samples and IgA in bronchoalveolar lavage fluid two weeks after the initial treatment, with peak concentrations in the respective samples on the 35th day. Moreover, immunoglobulins displayed a progressively enhanced avidity index, suggesting a selective binding to the spike protein. Finally, the pre-immunized group displayed a decrease in proinflammatory markers (TLR4, NLRP3, ILs) following SP challenge, compared to the non-immunized groups, along with better preservation of tissue morphology. Our probiotic-based technology provides an effective immunobiotic tool to protect individuals against disease and control infection spread.

Swept-source optical coherence tomography in ocular surface diseases: anterior segment analysis repeatability and its limits.

This study aims to evaluate the repeatability of anterior segment optical coherence tomography (AS-OCT) in diverse ocular surface disorder (OSD) cohorts, exploring various anterior segment parameters and their accuracy in different disease groups. A total of 239 participants across six distinct OSD groups and healthy controls underwent nonmydriatic AS-OCT imaging using the Tomey CASIA 2 device. Anterior segment parameters including anterior chamber depth, width, angle metrics, corneal thickness, keratometry, lens vault, and others were meticulously assessed. Statistical analyses determined repeatability limits and coefficients of variation for each parameter within the different OSD cohorts. Repeatability for anterior chamber and corneal parameters remained consistent across all OSD groups, indicating minimal impact of ocular surface disease on accuracy. The coefficient of variation (CoV) for the trabecular iris-space area was about 20% for all cohorts. Ocular surface inflammation emerged as a key factor in dry eye, affecting immune-mediated and non-immune conditions alongside age-related ocular surface changes. While anterior chamber depth measurements showed variations, particularly in immune (CoV = 2.5%) and non-immune (CoV = 3.8%) OSD groups, parameters like anterior chamber width and angle to angle showed similar values among the cohorts. Keratometry measures remained stable despite OSD (CoV lower than 1%). The Tomey CASIA 2 demonstrated reliable repeatability for measuring anterior segment parameters in diverse OSD cohorts. Despite challenges posed by dry eye conditions, this technology holds promise in assessing OSD, suggesting potential clinical protocols similar to those in healthy controls.

Virus-Like Particles Based on the Novel Goose Parvovirus (NGPV) VP2 Protein Protect Ducks against NGPV Challenge.

Novel goose parvovirus (NGPV), a genetic variant of goose parvovirus, has been spreading throughout China since 2015 and mainly infects ducklings with the symptoms of growth retardation, beak atrophy, and protruding tongue, leading to huge economic losses every year. A safe and effective vaccine is urgently needed to control NGPV infection. In this study, virus-like particles (VLPs) of NPGV were assembled and evaluated for their immunogenicity. The VP2 protein of NGPV was expressed in Spodoptera frugiperda insect cells using baculovirus as vector. The VP2 protein was efficiently expressed in the nucleus of insect cells, and the particles with a circular or hexagonal shape and a diameter of approximately 30 nm, similar to the NGPV virion, were observed using transmission electron microscopy (TEM). The purified particles were confirmed to be composed of VP2 using western blot and TEM, indicating that the VLPs of NGPV were successfully assembled. Furthermore, the immunogenicity of the VLPs of NGPV was evaluated in Cherry Valley ducks. The level of NGPV serum antibodies increased significantly at 1-4 weeks post-immunization. No clinical symptoms or deaths of ducks occurred in all groups after being challenged with NGPV at 4 weeks post-immunization. There was no viral shedding in the immunized group. However, viral shedding was detected at 3-7 days post-challenge in the non-immunized group. Moreover, VLPs can protect ducks from histopathological lesions caused by NGPV and significantly reduce viral load in tissue at 5 days post-challenge. Based on these findings, NGPV VLPs are promising candidates for vaccines against NGPV.

“Online survey of COVID-19 immunization and infection in patients with systemic juvenile idiopathic arthritis and adult-onset still’s disease.”

BackgroundPatients with systemic juvenile idiopathic arthritis (sJIA) and adult-onset Still’s disease (AOSD) have been under-represented in studies about safety of the COVID-19 immunization. We aimed to inquire about the safety and tolerability of COVID-19 immunization in this population.MethodsAn anonymous online survey on closed Facebook groups for patients and parents with self-reported sJIA/AOSD was posted from June 27th until August 30th, 2022. Continuous variables were analyzed using t-tests or the Mann-Whitney U test if non-normally distributed. Fisher`s tests were used for categorical variables.ResultsOf a total of 167 responses, 17 were excluded. Ninety-nine patients received the COVID-19 immunization, and 51 patients did not. Patients in both immunized and unimmunized groups had a similar history of disease complications such as macrophage activation syndrome (50% vs. 49%), lung disease (17% vs. 29%), arthritis (51% vs. 50%), and pericarditis/myocarditis (10% vs. 8%). Unimmunized patients were younger (median age 8 yo vs. 12 yo, p < 0.001) and had a higher incidence of a history of disease flare or severe side effects with other immunizations (24% vs. 4%, p < 0.001). Thirty-nine patients reported mostly mild immunization side effects. Severe side effects included 6 reports of disease flare and 2 reports of cardiac side effects (pericarditis and atrial fibrillation). Seven patients reported side effects lasting ≥ 8 days. Three patients developed AOSD following COVID-19 immunization, and 2 of them had the only hospital admissions for immunization side effects. Regarding COVID-19 infection, 46 patients were infected without full immunization, and 33 were infected after 2 doses of immunization. There was one hospitalization in the immunized group, compared to one ICU admission leading to death in the non-immunized group. There was a trend (p > 0.05) toward a higher risk of disease flare after COVID-19 infection among non-immunized patients (43%), compared to immunized patients (24%).ConclusionsThe COVID-19 immunization was well tolerated by sJIA/AOSD patients even in this group of patients with severe disease. There was a low incidence of disease flare with immunization. Most immunization side effects were mild and lasted < 7 days. The only ICU admission and death from COVID-19 infection occurred in unimmunized subjects.

High-Sucrose Diet Accelerates Arthritis Progression in a Collagen-Induced Rheumatoid Arthritis Model.

High dietary sugar and sweeteners are suspected to cause the development of rheumatoid arthritis (RA) symptoms through the induction of proinflammatory cytokine release. However, the mechanisms by which increased dietary sugar affects RA etiology are not yet fully understood. The study uses a mouse model of collagen-induced RA (CIA) to investigate the relationship between excessive sugar consumption and RA risk. RA-associated pathological features are assessed in the nonimmunized (NI) control group, the CIA-positive control group, and the CIA + high-sucrose diet (CIA+HS, 63% calories from sucrose) group. Compared with the CIA group, the CIA+HS group shows a greater increase in paw thickness and clinical scores, as well as, a higher degree of pannus formation and inflammation in the knee, ankle, and sole tissues. Moreover, the infiltration of immune cells is increased in the CIA+HS group. Although the expression of hepatic lipogenic genes, is not altered, that of toll-like receptor (TLR4) and IL-1β is considerably elevated in the CIA+HS group. These findings suggest that excessive sucrose consumption causes hepatic fibrosis and inflammation, contributing to the pathophysiology of RA.

Intramuscular Immunization with a Liposomal Multi-Epitope Chimeric Protein Induces Strong Cellular Immune Responses against Visceral Leishmaniasis.

Control of the intracellular parasite Leishmania (L.) requires the activation of strong type 1 cellular immune responses. Towards this goal, in the present study, a multiepitope chimeric protein named LiChimera was encapsulated into cationic liposomes and its protective efficacy against experimental visceral leishmaniasis was investigated. Liposomal LiChimera conferred significant protection against L. infantum as evidenced by the significantly reduced parasite loads in the spleen and liver. Protection detected in Lipo:LiChimera-immunized mice was dependent on the differentiation of long-lasting cellular immune responses and particularly the induction of antigen-specific multifunctional memory CD4+ TH1 and CD8+ T cells that persisted during infection, as evidenced by the persistent high production of IFN-γ and IL-2 and proliferation activity. Notably, protected mice were also characterized by significantly low numbers of non-regulatory CD4+ T cells able to co-produce IFN-γ and IL-10, an important population for disease establishment, as compared to non-immunized control group. Collectively, these results demonstrate that cationic liposomes containing LiChimera can be considered an effective candidate vaccine against visceral leishmaniasis.

Preemptive immune globulin therapy in sensitized lung transplant recipients

BackgroundSensitized lung transplant recipients are at increased risk of developing donor-specific antibodies, which have been associated with acute and chronic rejection. Perioperative intravenous immune globulin has been used in sensitized individuals to down-regulate antibody production. MethodsWe compared patients with a pre-transplant calculated panel reactive antibody ≥25% who did not receive preemptive immune globulin therapy to a historical control that received preemptive immune globulin therapy. Our cohort included 59 patients, 17 patients did not receive immune globulin therapy and 42 patients received therapy. ResultsDonor specific antibody development was numerically higher in the non-immune globulin group compared to the immune globulin group (58.8% vs 33.3%, respectively, odds ratio 2.80, 95% confidence interval [0.77, 10.79], p = 0.13). Median time to antibody development was 9 days (Q1, Q3: 7, 19) and 28 days (Q1, Q3: 7, 58) in the non-immune globulin and immune globulin groups, respectively. There was no significant difference between groups in the incidence of primary graft dysfunction at 72 h post-transplant or acute cellular rejection, antibody-mediated rejection, and chronic lung allograft dysfunction at 12 months. ConclusionThese findings are hypothesis generating and emphasize the need for larger, randomized studies to determine association of immune globulin therapy with clinical outcomes.

ITRAQ proteome analysis of insight into TLR20.2 functions through IFN1 signaling exerts regulatory effects on GCRV replication

Maternal immunization is an efficacious way to protect offspring from pathogen infections. To clarify the immune-enhancing mechanism of maternal immunization in grass carp, the iTRAQ assay was applied to screen differentially expressed proteins (DEPs) among eggs produced from maternal-immunized and non-immunized female grass carp. A total of 138 DEPs were obtained and TLR20.2 was the sole identified consensus DEP among the maternal-immunized and non-immunized groups. In general, the gene and protein expressions of TLR20.2 in the egg cell and early developmental stage embryos could be enhanced by maternal-immunized treatment. The mRNA levels of tlr20.2 were up-regulated in the liver, head kidney, and spleen in response to grass carp reovirus (GCRV) infection. Mechanistically, TLR20.2 functions through the IFN1 signaling and displayed inhibitory functions on GCRV replication by remarkably down-regulation of vp2 and vp7 expressions. The HSP90 was identified to be one of the proteins that interacted with TLR20.2, which coexpressed with TLR20.2 and mainly concentrated around the central veins. HSP90 promotes GCRV replication by inhibiting the irf3, irf7, and ifn1 expressions, which resulted in remarkably increased vp2 and vp7 gene expressions. The HMGB1a and HMGB1b could bind to the TLR20–2 promoter, and showed positive effects on tlr20.2 expression by significantly promoting its promoter activity (P < 0.01). Moreover, HMGB1a and HMGB1b exerted negative effects on HSP90 expression and thus the GCRV replication. Overall, this study provided molecular evidence that maternal immunization treatment protect against GCRV infection through the enhancement of TLR20.2 expression, and the HMGB1-TLR20.2-HSP90-IFN axis confers regulatory effects on GCRV replication. The results are novel findings to help elucidate the resistance-enhancing mechanism in fish species.

A live attenuated RHΔompdcΔuprt mutant of Toxoplasma gondii induces strong protective immunity against toxoplasmosis in mice and cats

BackgroundToxoplasma gondii is an obligate intracellular apicomplexan parasite and is responsible for zoonotic toxoplasmosis. It is essential to develop an effective anti-T. gondii vaccine for the control of toxoplasmosis, and this study is to explore the immunoprotective effects of a live attenuated vaccine in mice and cats.MethodsFirst, the ompdc and uprt genes of T. gondii were deleted through the CRISPR-Cas9 system. Then, the intracellular proliferation and virulence of this mutant strain were evaluated. Subsequently, the immune responses induced by this mutant in mice and cats were detected, including antibody titers, cytokine levels, and subsets of T lymphocytes. Finally, the immunoprotective effects were evaluated by challenge with tachyzoites of different strains in mice or cysts of the ME49 strain in cats. Furthermore, to discover the effective immune element against toxoplasmosis, passive immunizations were carried out. GraphPad Prism software was used to conduct the log-rank (Mantel–Cox) test, Student’s t test and one-way ANOVA.ResultsThe RHΔompdcΔuprt were constructed by the CRISPR-Cas9 system. Compared with the wild-type strain, the mutant notably reduced proliferation (P < 0.05). In addition, the mutant exhibited virulence attenuation in both murine (BALB/c and BALB/c-nu) and cat models. Notably, limited pathological changes were found in tissues from RHΔompdcΔuprt-injected mice. Furthermore, compared with nonimmunized group, high levels of IgG (IgG1 and IgG2a) antibodies and cytokines (IFN-γ, IL-4, IL-10, IL-2 and IL-12) in mice were detected by the mutant (P < 0.05). Remarkably, all RHΔompdcΔuprt-vaccinated mice survived a lethal challenge with RHΔku80 and ME49 and WH6 strains. The immunized sera and splenocytes, especially CD8+ T cells, could significantly extend (P < 0.05) the survival time of mice challenged with the RHΔku80 strain compared with naïve mice. In addition, compared with nonimmunized cats, cats immunized with the mutant produced high levels of antibodies and cytokines (P < 0.05), and notably decreased the shedding numbers of oocysts in feces (95.3%).ConclusionsThe avirulent RHΔompdcΔuprt strain can provide strong anti-T. gondii immune responses, and is a promising candidate for developing a safe and effective live attenuated vaccine.Graphical abstract

Using an Aluminum Hydroxide-Chitosan Matrix Increased the Vaccine Potential and Immune Response of Mice against Multi-Drug-Resistant Acinetobacter baumannii.

Acinetobacter baumannii is a Gram-negative, immobile, aerobic nosocomial opportunistic coccobacillus that causes pneumonia, septicemia, and urinary tract infections in immunosuppressed patients. There are no commercially available alternative antimicrobials, and multi-drug resistance is an urgent concern that requires emergency measures and new therapeutic strategies. This study evaluated a multi-drug-resistant A. baumannii whole-cell vaccine, inactivated and adsorbed on an aluminum hydroxide-chitosan (mAhC) matrix, in an A. baumannii sepsis model in immunosuppressed mice by cyclophosphamide (CY). CY-treated mice were divided into immunized, non-immunized, and adjuvant-inoculated groups. Three vaccine doses were given at 0D, 14D, and 28D, followed by a lethal dose of 4.0 × 108 CFU/mL of A. baumannii. Immunized CY-treated mice underwent a significant humoral response, with the highest IgG levels and a higher survival rate (85%); this differed from the non-immunized CY-treated mice, none of whom survived (p < 0.001), and from the adjuvant group, with 45% survival (p < 0.05). Histological data revealed the evident expansion of white spleen pulp from immunized CY-treated mice, whereas, in non-immunized and adjuvanted CY-treated mice, there was more significant organ tissue damage. Our results confirmed the proof-of-concept of the immune response and vaccine protection in a sepsis model in CY-treated mice, contributing to the advancement of new alternatives for protection against A. baumannii infections.

Developmental outcomes in children born to women with possible subclinical rubella exposures during pregnancy.

This study investigated outcomes of children born to women who seroconverted to rubella immune during pregnancy. In a prior 2012-2013 study of 296 women who were rubella nonimmune, 26 (8.8%) seroconverted to rubella immune during pregnancy. These same women and their now 8-9 years-old children were queried as to the children's developmental health. After removing exclusions and those lost to follow-up, the total response rate was 115/204 (56.4%). Three sets of twins in the nonimmune group increased the total to 118. The seroconversion group had more autism (12.5% vs. 3.9%, p = 0.19), ADHD (37.5% vs. 18.6%, p = 0.10), and any developmental disability (43.8% vs. 31.4%, p = 0.39) but none showed a statistical difference between the two groups. Compared to Autism and Developmental Disabilities Monitoring data, the seroconversion group had a greater prevalence of autism (odds ratio [OR] 6.07, p = 0.051, nonsignificant); and to data derived from the National Health Interview Survey, a nonsignificant higher odds of autism (OR 5.57, p = 0.060), higher odds of ADHD (OR 5.65, p = 0.0027) and of any developmental disability (OR 3.59, p = 0.014). The nonimmune group also demonstrated a statistically significant increase for both ADHD and any developmental disability, but not for autism.

Investigation into the potential of using UV-treated sporulated oocysts of Eimeria tenella as a local solution to immunization of chickens against caecal coccidiosis.

In this study, we aim to evaluate the immune response of chickens to UV-treated sporulated oocysts as a means of protection against caecal coccidiosis caused by field strains of Eimeria tenella. Two groups of chicks were immunized using prepared UV-treated oocysts of E. tenella and challenged at day 20 post hatching. The first group was immunized only once at day 1 post hatching, the second group was immunized twice (day 1 and day 8 post hatching). Two non-immunized control groups were used: the first group was challenged with E. tenella, while the second group remained uninfected. The effectiveness of immunization on production and animal health was evaluated by the following criteria: body weight, feed conversion ratio, blood in faeces, mortality, lesion scores and oocyst output. The two immunized groups showed a significantly better performance in body weight, weight gain and lesion scores than the non-immunized group. However, all three groups performed significantly worse than the unchallenged group. The mortality of the non-immunized infected group was high (70%) while mortality in both immunized and unchallenged groups of chickens was significantly lower (range 2.2 to 4.4%) than the infected group (p < 0.05). The production of oocysts in faeces, post-infection, was significantly higher in the non-immunized group compared to the immunized group (p < 0.05) and both were significantly higher than the uninfected group (p < 0.05). In conclusion, immunization by prepared UV-irradiated oocysts is effective in stimulating at least a partial protective immunity in immunized chickens against caecal coccidiosis.

Comparative evaluation of gold nanoparticles and Alum as immune enhancers against rabies vaccine and related immune reactivity, physiological, and histopathological alterations: in vivo study.

The present study aimed to compare the immune-enhancing potential of gold nanoparticles (AuNPs) to Alum against rabies vaccine and the related immunological, physiological, and histopathological effects. Alum and AuNPs sole and in combination with rabies vaccine were used at 0.35 mg/mL and 40 nM/mL, respectively. Rats used were categorized into six groups (20/each): control rats, rabies vaccine, aluminum phosphate gel, rabies vaccine adsorbed to Alum, AuNPs, and rabies vaccine adjuvant AuNPs. Liver and kidney functions were in the normal range after AuNPs and Alum adjuvanted vaccine compared to control. Interleukin-6 and interferon-γ levels were significantly increased in groups immunized with Alum and AuNPs adjuvanted vaccine, the peak level was in the case of AuNP adjuvanted vaccine on the 14th day. Ninety days post-vaccination, total immunoglobulin G (IgG) against adjuvanted rabies vaccine showed a significantly elevated anti-rabies IgG with AuNPs and Alum adsorbed vaccine compared with unadjuvanted one. The total antioxidant capacity, malondialdehyde (MDA) levels, superoxide dismutase, and glutathione peroxidase activities were significantly increased post-adjuvanted AuNPs adjuvanted vaccine vaccination than in Alum adsorbed vaccine, while MDA was significantly decreased. The histopathological examination revealed detectable alterations post-AuNPs and Alum adjuvanted vaccine immunization compared with liver and kidney profiles post-administration of unadjuvanted and non-immunized groups, meanwhile, splenic tissue revealed hyperplasia of lymphoid follicles indicating increased immune reactivity. The AuNPs are promising enhancers of the immune response as Alum, and the undesirable effects of AuNPs could be managed by using suitable sizes, shapes, and concentrations.

Exploring the performance of Escherichia coli outer membrane vesicles as a tool for vaccine development against Chagas disease.

Vaccine development is a laborious craftwork in which at least two main components must be defined: a highly immunogenic antigen and a suitable delivery method. Hence, the interplay of these elements could elicit the required immune response to cope with the targeted pathogen with a long-lasting protective capacity. Here we evaluate the properties of Escherichia coli spherical proteoliposomes - known as outer membrane vesicles (OMVs) - as particles with natural adjuvant capacities and as antigen-carrier structures to assemble an innovative prophylactic vaccine for Chagas disease. To achieve this, genetic manipulation was carried out on E. coli using an engineered plasmid containing the Tc24 Trypanosoma cruzi antigen. The goal was to induce the release of OMVs displaying the parasite protein on their surface. As a proof of principle, we observed that native OMVs - as well as those carrying the T. cruzi antigen - were able to trigger a slight, but functional humoral response at low immunization doses. Of note, compared to the non-immunized group, native OMVs-vaccinated animals survived the lethal challenge and showed minor parasitemia values, suggesting a possible involvement of innate trained immunity mechanism. These results open the range for further research on the design of new carrier strategies focused on innate immunity activation as an additional immunization target and venture to seek for alternative forms in which OMVs could be used for optimizing vaccine development.

Immunocastrated female pigs’ social and feeding behaviour

This study compared the social and feeding behaviour of immunocastrated female pigs using different immunocastration protocols. We used seventy-two gilts from industrial crossbreeding (Agroceres × Topigs) at 15 weeks of age. The pigs were distributed in a randomised design with three treatments. The second dose of the immunocastration vaccine was applied in two groups, six weeks before slaughter (I6) and four weeks before slaughter (I4). A non-immunised group (NI) was used for comparison. Due to the divergence in the [...]

Detection of clinical and subclinical Foot and Mouth Disease Virus in Cattle in Al-Najaf Province.

Foot-and-mouth disease (FMD) is a highly transmissible disease caused by Aphthovirus of the family Picornaviridae. This study aimed to investigate the serological approach (non-structural protein [NSP] analysis) of 3ABC enzyme-linked immunosorbent assay (ELISA) to diagnose FMD cattle in vaccinated and unvaccinated animals. A total of 84 serum specimens, including non-vaccinated, single-vaccinated, and multi-vaccinated samples, were collected from four districts in Baghdad Province, Iraq, to evaluate the antibodies to NSP of the FMD virus. The ELISA was used to detect antibodies (NSP) of FMDV in the serum of cattle. The result showed that the seroprevalence was estimated at 34% (29/84) in farm animals. The seroprevalence rates of FMD in relation to the age of infected animals were obtained at 21%, 7%, and 6% in 9-23-, 24-36-, and ≥ 36-month-old groups, respectively. The consequences of the examination of the sera from naive, immunized, and non-immunized infected farm animals applying 3ABC-ELISA were presented; accordingly, the incidence rates of FMD infection in non-vaccinated and vaccinated animals were 18 (75%) and 11 (18%) respectively. Negative results were recorded in the immunized group 49 (82%) higher than in the non-immunized group 6 (25%). Evaluation of NSP antibodies to isolate vaccinated animals from infected ones showed that the application of these assays was significantly useful for FMD prevention and control management programs in infected areas.

Seroprotection of Hepatitis B Vaccine in Dental Students Two Decades after Infant Immunization and the Possible Need for Revaccination.

This study aimed to assess hepatitis B surface antibody (anti-HBs) persistence among dental students two decades after infant vaccination and immune response after revaccination or booster dose in nonimmune groups. A cross-sectional study was performed using laboratory reports for anti-HBs performed to dental students at the Umm al-Qura University from 2016 to 2020. Reports were classified according to baseline antibody titer into group I (titer <10 mIU/mL), group II (titer 10 to <100 mIU/mL), and group III (titer ≥100 mIU/mL). The basal antibody titer of each group was correlated to student's gender and birth year and compared with postrevaccination or booster dose titer in groups I and II. Data of baseline and postrevaccination anti-HBs antibody titers were analyzed using Statistical Package for Social Science (SPSS). One-way ANOVA was used to compare between different means for antibody titers of students as well as baseline and postrevaccination antibody levels for nonimmune students with nonprotective antibody titers. Pairwise multiple comparison of the difference between baseline and postrevaccination anti-HBs antibody titers were done by post hoc Tukey's honestly significant difference (HSD) test. Chi-squared test was used for comparing between the frequencies. A p-Value of ≤0.05 was considered significant and p < 0.01 was considered highly significant. A significant percentage (73.6%) of students had antibody titer <10 mIU/mL, while only 4.8% had antibody titer ≥100 mIU/mL with nonsignificant difference between both genders (χ 2 =3.784, p = 0.151). A statistically nonsignificant difference was also found between the three categories of anti-HBs antibody titers among students with different birth dates (χ 2 = 13.817, p = 0.182). After revaccination of nonimmune students, 100% of them showed strongly protective antibody titers with mean of 842.88 to 844.58 mIU/mL. A highly significant difference was observed between the mean baseline and postrevaccination antibody titers in both genders, with a higher mean of post revaccination (p = 0.000). Two decades after infant immunization, a significant percentage of dental students failed to maintain the anti-HBs seroprotective titer. So titer measurement should be made compulsory before they begin their clinical training and revaccination or booster dose should be given to nonimmune students to maintain a high protection level.