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Viruses ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 21
Author(s):  
David Tapia ◽  
Juan Kuznar ◽  
Rodolfo Farlora ◽  
José M. Yáñez

The IPN virus (IPNV) causes a highly contagious disease that affects farmed salmonids. IPNV isolates have been phylogenetically classified into seven genogroups, of which two are present in Chile, genogroups 1 and 5. This study aimed to compare the transcriptomic response of rainbow trout fry challenged with two Chilean isolates of IPNV, RTTX (genogroup 1), and ALKA (genogroup 5). Tissue samples from challenged individuals and controls were taken at 1, 7, and 20 days post-challenge and analyzed by RNA-Seq. The results revealed that infection with RTTX elicited a greater modulation of the trout transcriptome compared to ALKA infection, generating a greater number of highly differentially expressed genes in relation to the control fish. Gene Ontology enrichment indicated that functions related to the inflammatory and immune responses were modulated in fish challenged with both isolates throughout the trial, but with different regulation patterns. On day 1 post challenge, these functions were activated in those challenged with ALKA, but suppressed in RTTX-challenged fish. These results suggest that rainbow trout exhibit a differential transcriptomic response to infection with the two genetically distinct IPNV isolates, especially at early times post-infection.


Author(s):  
Keelee J McCarty ◽  
Jessie E Tipton ◽  
Ralph E Ricks ◽  
Jessica Danielo ◽  
Jesse S Thompson ◽  
...  

Abstract The objective was to determine the effects of an immunomodulatory feed ingredient following weaning on cytokine expression and fecal microbial populations of heifers. Commercial Angus heifers (n = 72) were weaned (227 ± 7 d of age), blocked by BW (n = 9 blocks) and randomly assigned to one of 2 pens per block. Pens within weight block (4 heifers/pen) were then randomly assigned to treatments. Heifers were fed twice daily from d 0-60 (to gain 0.75kg/day) and top-dressed with either 18g/heifer/d of the immunomodulatory feed ingredient (Celmanax; Arm and Hammer Animal Nutrition, Princeton, NJ, USA; CEL) or corn-germ meal (CON). Blood samples were collected on d 0, 15, 30, 45, 60 and fecal grab samples on d 0 of the feeding trial. After d 60, two heifers per pen (n=32) were randomly selected for a transportation challenge. Serum samples were collected at h 0, 4, 8, 12 and fecal grab samples at h -24, 0, 24 and 7d post-challenge. Blood samples were analyzed for interferonγ (IFNγ), interleukin-8 (IL-8), and haptoglobin (HP) using commercially available ELISA kits and qRT-PCR for genes of interest associated with cytokine expression. Fecal samples were enumerated for Clostridia and E. coli using selective media (≤ 5 isolates from each media/sample), tested to determine if they were C. perfringens or pathogenic E. coli, and then enriched for detection of Salmonella. Data was analyzed via ANOVA. During the feeding trial, HP was reduced (P = 0.018) in CEL compared to CON at d 15, 45, and 60, while IFNγ and IL-8 did not differ (P > 0.080) between treatments. All cytokines were decreased (P < 0.001) in CEL compared to CON during the challenge. During the feeding trial, HP mRNA was increased (P = 0.045) in CEL compared to CON at d 30 and 60. Similarly, IFNγ mRNA was increased (P = 0.040) in CEL compared to CON, however, other genes of interest did not differ (P > 0.172). Both C. perfringens and total E. coli counts were decreased (P = 0.036) in CEL compared to CON at 24h after the start of the transportation challenge. Clostridia and pathogenic E. coli counts did not differ (P = 0.941) between treatments. Total Clostridia and E. coli counts were increased (P < 0.014) 24h post-challenge. All microbial populations, except pathogenic E. coli, observed decreased (P ≤ 0.009) counts from 24h to 7d post-challenge. Overall, Celmanax supplementation decreased circulating cytokines, and altered microbial populations and gene expression, thus, may serve a role in preparing animals to better cope with immunological challenges.


Author(s):  
Stefan Saadiq ◽  
Roy Valenzuela ◽  
Jing Wang ◽  
Zenong Yin ◽  
Deborah Parra-Medina ◽  
...  

In the United States, the Latinx population has the highest prevalence of physical inactivity compared with other ethnicities. Research shows that work-based physical activity interventions have been widely implemented in the non-Latinx population and effectively increase physical activity in the non-Latinx population. In an effort to improve physical activity and reduce obesity among the Latinx population, we conducted 10,000 Steps for 100 Days, an employer-based walking challenge campaign, to increase walking engagement among Latinx employees located in El Paso, Texas. Participants reported their number of steps using a pedometer or smartphone. Step counts were collected at baseline, 2 weeks post challenge, and 6 months post challenge. Screenshots of the tracking device were uploaded to an online tracker. Regression analysis was conducted to identify covariates associated with baseline and 2-week and 6-month average daily steps. Generalized estimating equations (GEE) were performed to predict steps over time by demographic characteristics. Participation in the 10,000 Steps for 100 Days walking challenge was associated with a sustained increase in average daily steps. Participants with less than 7000 steps per day demonstrated the greatest increase in average daily steps (921 steps at 2 weeks; 1002.4 steps at 6 months). Demographic characteristics were not significant predictors of average steps, except that married participants had higher average steps. Participants with 10,000 or more daily steps had a 51% (p = 0.031) higher chance of having a professional occupation than a non-professional one compared to those with 7000 or fewer daily steps. We provided initial evidence that the walking challenge is an effective approach for improving physical activity in the Latinx population.


Vaccines ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1416
Author(s):  
Magdalena Maj ◽  
Gina M. Fake ◽  
John H. Walker ◽  
Ryan Saltzman ◽  
John A. Howard

To investigate whether oral administration of maize-produced S antigen can provide passive immunity to piglets against porcine epidemic diarrhea virus (PEDV), 16 pregnant sows were randomly assigned to one of four treatments: (1) injection of PEDV vaccine (INJ), (2) maize grain without S protein (CON), (3) maize grain containing low dose of S antigen (LOV) and (4) maize grain containing a high dose of S antigen (HOV). Vaccines were administered on days 57, 85 and 110 of gestation. Sows’ serum and colostrum were collected at farrowing and milk on day 6 post-challenge to quantify neutralizing antibodies (NABs) and cytokines. Piglets were challenged with PEDV 3–5 d after farrowing, and severity of disease and mortality assessed on day 11 post-challenge. Disease severity was lower in LOV and INJ compared with HOV and CON, whereas the survival rate increased in piglets from LOV sows compared with HOV and CON (p ≤ 0.001). Higher titers of NABs and lower levels of cytokine granulocyte-macrophage colony-stimulating factor in sows’ milk were positively correlated with piglet survivability (p ≤ 0.05). These data suggest that feeding S protein in corn to pregnant sows protects nursing piglets against PEDV.


2021 ◽  
Author(s):  
Robert Wagner ◽  
Sabine S. Eckstein ◽  
Louise Fritsche ◽  
Katsiaryna Prystupa ◽  
Sebastian Hoerber ◽  
...  

While oral glucose ingestion typically leads to a decrease in circulating glucagon levels, a substantial number of persons display stable or rising glucagon concentrations when assessed by radioimmunoassay (RIA). However, these assays show cross-reactivity to other proglucagon cleavage products. Recently, more specific assays became available, therefore we systematically assessed glucagon and other proglucagon cleavage products and their relation to metabolic health. We used samples from 52 oral glucose tolerance tests (OGTT) that were randomly selected from an extensively phenotyped study cohort. Glucagon concentrations quantified with RIA were non-suppressed at 2 hours of the OGTT in 36 % of the samples. Non-suppressors showed lower fasting glucagon levels compared to suppressors (p=0.011). Similar to RIA measurements, ELISA-derived fasting glucagon was lower in non-suppressors (p<0.001). Glucagon 1-61 as well as glicentin kinetics were significantly different between suppressors and non-suppressors (p=0.004 and p=0.002, respectively) with higher concentrations of both hormones in non-suppressors. Levels of insulin, C-peptide, and free fatty acids were comparable between groups. Non-suppressors were leaner and had lower plasma glucose concentrations (p=0.03 and p=0.047, respectively). Despite comparable liver fat content and insulin sensitivity (p≥0.3), they had lower 2-hour post-challenge glucose (p=0.01). Glucagon 1-61, glicentin and GLP-1 partially account for RIA-derived glucagon measurements due to cross-reactivity of the assay. However, this contribution is small, since the investigated proglucagon cleavage products contribute less than 10% to the variation in RIA measured glucagon. Altered glucagon levels and higher post-challenge incretins are associated with a healthier metabolic phenotype that is known to be indicative for reduced cardiovascular risk, cancer incidence, and mortality.


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2476
Author(s):  
Md Tohidul Islam ◽  
Tony Arioli ◽  
David M. Cahill

Plant priming is an induced physiological state where plants are protected from biotic and abiotic stresses. Whether seaweed extracts promote priming is largely unknown as is the mechanism by which priming may occur. In this study, we examined the effect of a seaweed extract (SWE) on two distinct stages of plant priming (priming phase and post-challenge primed state) by characterising (i) plant gene expression responses using qRT-PCR and (ii) signal transduction responses by evaluating reactive oxygen species (ROS) production. The SWE is made from the brown algae Ascophyllum nodosum and Durvillaea potatorum. The priming phase was examined using both Arabidopsis thaliana and Solanum lycopersicum. At this stage, the SWE up-regulated key priming-related genes, such as those related to systemic acquired resistance (SAR) and activated the production of ROS. These responses were found to be temporal (lasting 3 days). The post-challenge primed state was examined using A. thaliana challenged with a root pathogen. Similarly, defence response-related genes, such as PR1 and NPR1, were up-regulated and ROS production was activated (lasting 5 days). This study found that SWE induces plant priming-like responses by (i) up-regulating genes associated with plant defence responses and (ii) increasing production of ROS associated with signalling responses.


2021 ◽  
Vol 25 (1) ◽  
pp. 91-104
Author(s):  
AL- Mashhadani, F.J. K. ◽  
AL-Samarrae, S.A. G

A comparative trial between the effect of 3rd stage Dictyocaulus filaria larval vaccine attenuated by continuous emission of visible Helium – Neon Laser of ImW and wave length of ( 632.8 ) nm of (5) minutes exposure that of gamma attenuated larvae at 0.5 k. gray ( Co as radiation Source ) was designed. Each of the two attenuated larval vaccines was given to a group of ( 5 ) kids each . Double immunization doses at ( 35 ) days interval from each vaccine were given orally. The first dose contained ( 1000 ) larvae and the second one ( 2000 ) for each . A challenge dose of ( 100 ) non- irradiated larvae /kg body weight was given after ( 5 ) week to the vaccinated groups and a control non- vaccinated (5 kids ) 3rd group. All animals were slaughtered after 6 weeks post challenge.  Results showed that both vaccines revealed 80.7% and 78.1% protection respectively for worm burden as compared to control. Laser attenuated vaccine exhibited a statistically significant inhibition in the fecundity of female worms and larvae secretion in faeces in comparison with the gamma irradiated vaccine. 


2021 ◽  
Vol 8 (Supplement_1) ◽  
pp. S128-S129
Author(s):  
Lindsay Hill-Batorski ◽  
Yasuko Hatta ◽  
Michael Moser ◽  
David Marshall ◽  
Pamuk Bilsel

Abstract Background Quadrivalent inactivated influenza vaccines (QIV) induce neutralizing antibodies (Abs) against the viral hemagglutinin (HA). Despite annual update of HA vaccine antigens to match circulating strains, current vaccines provide ~60% vaccine effectiveness (VE). QIV VE can be as low as 10% when circulating strains do not match vaccine HA. The live M2SR (M2-deficient single replication) influenza vaccine candidate has previously shown broad humoral, mucosal and cellular immune responses and protection against multiple influenza A subtypes. Here we show similar properties with the Quadrivalent M2SR (Quad M2SR) against drifted influenza B challenge in comparison to QIV. Methods Ferrets pre-infected with influenza H1N1 and B/Yamagata viruses, were immunized intranasally (IN) with PBS (Mock) or Quad M2SR, or intramuscularly with Fluzone QIV. Serum collected post-vaccination was evaluated for Ab responses. Forty-two days after vaccination, ferrets were challenged IN with 106 pfu of B/Brisbane/60/2008 (Victoria lineage) influenza virus. Nasal washes were taken for 7 days post-challenge and evaluated for challenge virus by TCID50 assay. Nasal turbinates, trachea and lungs were also evaluated for virus. Results Quad M2SR and QIV elicited high serum Abs against the vaccine strain B/Colorado/06/2017 (Fig. 1A) and against the drifted influenza B challenge strain B/Brisbane/60/2008 (Fig. 1B) in ferrets with preexisting immunity. Like Mock, ferrets who received QIV displayed both weight loss (6.2%, Fig. 2A) and a rise in temperature (1.1oC, Fig. 2B) after challenge. In contrast, the Quad M2SR group did not exhibit any significant weight or temperature changes after challenge. Quad M2SR controlled the drifted challenge virus better than QIV as evidenced by significantly lower or absent post-challenge virus titer in nasal washes (Fig. 3A) and nasal turbinates (Fig. 3B). Figure 1. Serum Neutralization Titers Post-Vaccination Plaque reduction neutralization test (PRNT) antibody titers for Quad M2SR and QIV against matched Influenza B vaccine strain B/Colorado/06/2017 (Fig. 1A) and drifted strain B/Brisbane/60/2008 (Fig. 1B) on pre-study (Day -3), pre-vaccination (Day 28), and 3 weeks post vaccination (Day 51). The detection limit of the assay (horizontal dashed line) was 15 PRNT50. Figure 2. Post-challenge body weight and temperature changes Percent body weight changes (Fig. 2A) and average body temperatures changes (Fig. 2B) following challenge with drifted Influenza B strain B/Brisbane/60/2008 for ferrets vaccinated with Quad M2SR or QIV. Figure 3. Post-challenge virus titers in respiratory tract. Viral titers in nasal washes (Fig. 3A) and nasal turbinates (Fig. 3B) collected post-challenge with Influenza B strain B/Brisbane/60/2008 in ferrets vaccinated with Quad M2SR or QIV. No virus was detected in the trachea or lungs. The detection limit of the assay (horizontal dashed line) was 1.5 log10 TCID50/mL and 20 FFU respectively. Virus titer between groups was significant on day 3 of the nasal washes: one-way analysis of variance (ANOVA) with Multiple t tests to compare between groups, #p&lt;0.05,&gt;&lt;0.01,&gt;&lt;&gt; Conclusion Despite eliciting similar Ab titers, the Quad M2SR demonstrated superior protection compared to QIV in a drifted influenza B challenge model in ferrets. These results suggest that the intranasal M2SR platform may confer additional advantages over currently available vaccines. Quad M2SR is in late-stage development for testing in a first-in-human clinical study. Disclosures Lindsay Hill-Batorski, PhD, FluGen (Employee) Yasuko Hatta, DVM, PhD, FluGen (Employee) Michael Moser, PhD, FluGen (Employee) David Marshall, BS, FluGen (Employee) Pamuk Bilsel, PhD, FluGen (Employee)


Vaccines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1189
Author(s):  
Kiril M. Dimitrov ◽  
Tonya L. Taylor ◽  
Valerie C. Marcano ◽  
Dawn Williams-Coplin ◽  
Timothy L. Olivier ◽  
...  

Newcastle disease (ND) is one of the most economically important poultry diseases. Despite intensive efforts with current vaccination programs, this disease still occurs worldwide, causing significant mortality even in vaccinated flocks. This has been partially attributed to a gap in immunity during the post-hatch period due to the presence of maternal antibodies that negatively impact the replication of the commonly used live vaccines. In ovo vaccines have multiple advantages and present an opportunity to address this problem. Currently employed in ovo ND vaccines are recombinant herpesvirus of turkeys (HVT)-vectored vaccines expressing Newcastle disease virus (NDV) antigens. Although proven efficient, these vaccines have some limitations, such as delayed immunogenicity and the inability to administer a second HVT vaccine post-hatch. The use of live ND vaccines for in ovo vaccination is currently not applicable, as these are associated with high embryo mortality. In this study, recombinant NDV-vectored experimental vaccines containing an antisense sequence of avian interleukin 4 (IL4R) and their backbones were administered in ovo at different doses in 18-day-old commercial eggs possessing high maternal antibodies titers. The hatched birds were challenged with virulent NDV at 2 weeks-of-age. Post-hatch vaccine shedding, post-challenge survival, challenge virus shedding, and humoral immune responses were evaluated at multiple timepoints. Recombinant NDV (rNDV) vaccinated birds had significantly reduced post-hatch mortality compared with the wild-type LaSota vaccine. All rNDV vaccines were able to penetrate maternal immunity and induce a strong early humoral immune response. Further, the rNDV vaccines provided protection from clinical disease and significantly decreased virus shedding after early virulent NDV challenge at two weeks post-hatch. The post-challenge hemagglutination-inhibition antibody titers in the vaccinated groups remained comparable with the pre-challenge titers, suggesting the capacity of the studied vaccines to prevent efficient replication of the challenge virus. Post-hatch survival after vaccination with the rNDV-IL4R vaccines was dose-dependent, with an increase in survival as the dose decreased. This improved survival and the dose-dependency data suggest that novel attenuated in ovo rNDV-based vaccines that are able to penetrate maternal immunity to elicit a strong immune response as early as 14 days post-hatch, resulting in high or full protection from virulent challenge, show promise as a contributor to the control of Newcastle disease.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 381-382
Author(s):  
Samantha N Barker ◽  
Treylr Jackson ◽  
John Richeson ◽  
Jeff A Carroll ◽  
Nicole C Burdick-Sanchez ◽  
...  

Abstract The objective of this study was to evaluate antioxidant capacity in plasma of beef calves challenged with LPS. Following an initial feeding period of 40 d, steers (n = 32; 379 kg ± 30.7) were transported to the Livestock Issues Research Unit’s Bovine Immunology Research and Development Complex and challenged intravenously with LPS (0.25 µg/kg BW) on d 41. Blood samples were collected via jugular catheter at -2, 0, 2, 4, 6, 8, 10, 12, 18, 24, 36 and 48 h relative to the LPS challenge at 0 h. Blood samples were processed to isolate plasma for indicators of oxidative stress with a colorimetric assay to determine ferric reducing antioxidant power (FRAP) values via concentration of ferrous iron (µM). Data were analyzed as repeated measures using the GLIMMIX procedure of SAS. Antioxidant values did vary with time (P &lt; 0.001) being greater (P &lt; 0.05) at -2, 0, 2, 36, and 48 h. Antioxidant capacity was reduced at 6 and 8 h (P &lt; 0.05), with the least FRAP value observed at 8 h post-challenge. Antioxidant capacity increased (P &lt; 0.05) again at 10 h, showing similar (P &gt; 0.05) concentrations to those observed at 4 h. By 24 h post-challenge, plasma FRAP values increased (P &lt; 0.05) similar to initial values at -2, 0, and 2 h. It can be inferred that oxidative stress contributes to reduced antioxidant capacity, ultimately interfering with animal growth and productivity. While these values reflect the oxidative stress response to an acute endotoxin challenge, and a subsequent recovery returning to homeostasis within 24 to 48 h, they may also correlate with other physiological and immunological indicators associated with an acute endotoxin challenge.


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