Intravenous Challenge Research Articles

Oral feeding as well as intravenous administration of biodegradable nanoparticles containing antigen and dexamethasone induces antigen-specific immune tolerance

Abstract Polymeric nanoparticles containing both antigens and drugs have remarkable advantages because they can specifically deliver the antigens and the drugs to phagocytes such as dendritic cells and macrophages, thereby reducing the potential systemic side effects of the drugs. In the present study, we fabricated polymeric nanoparticles (NP) containing both ovalbumin (OVA) and dexamethasone (Dex) (NP[OVA+Dex]) using biodegradable and biocompatible polymer poly(lactic-co-glycolic acid) (PLGA), after which their immunomodulatory effects were examined. Immature dendritic cells treated with NP[OVA+Dex] were profoundly suppressed in both MHC class II- and class I-restricted OVA peptide presentation. In addition, mice injected with NP[OVA+Dex] were profoundly suppressed in generating OVA-specific cytotoxic T cells and also in producing OVA-specific IgG with concomitant increase of regulatory T cells. Furthermore, feeding of mice with NP[OVA+Dex] induced OVA-specific immune tolerance, as demonstrated by significant decrease in generating OVA-specific immune responses upon subsequent intravenous challenge with the nanoparticles containing OVA only. The present study demonstrates that oral feeding as well as intravenous injection of PLGA nanoparticles encapsulated with both antigen and Dex is a useful means for inducing antigen-specific immune tolerance.

Human lipopolysaccharide models provide mechanistic and therapeutic insights into systemic and pulmonary inflammation.

Inflammation is a key feature in the pathogenesis of sepsis and acute respiratory distress syndrome (ARDS). Sepsis and ARDS continue to be associated with high mortality. A key contributory factor is the rudimentary understanding of the early events in pulmonary and systemic inflammation in humans, which are difficult to study in clinical practice, as they precede the patient's presentation to medical services. Lipopolysaccharide (LPS), a constituent of the outer membrane of Gram-negative bacteria, is a trigger of inflammation and the dysregulated host response in sepsis. Human LPS models deliver a small quantity of LPS to healthy volunteers, triggering an inflammatory response and providing a window to study early inflammation in humans. This allows biological/mechanistic insights to be made and new therapeutic strategies to be tested in a controlled, reproducible environment from a defined point in time. We review the use of human LPS models, focussing on the underlying mechanistic insights that have been gained by studying the response to intravenous and pulmonary LPS challenge. We discuss variables that may influence the response to LPS before considering factors that should be considered when designing future human LPS studies.

Synthetic Peptides Containing Three Neutralizing Epitopes of Genotype 4 Swine Hepatitis E Virus ORF2 induced Protection against Swine HEV Infection in Rabbit.

Genotype 4 hepatitis E virus (HEV) is a zoonotic pathogen transmitted to humans through food and water. Previously, three genotype 4 swine HEV ORF2 peptides (407EPTV410, 410VKLYTS415, and 458PSRPF462) were identified as epitopes of virus-neutralizing monoclonal antibodies that partially blocked rabbit infection with swine HEV. Here, individual and tandem fused peptides were synthesized, conjugated to keyhole limpet hemocyanin (KLH), then evaluated for immunoprotection of rabbits against swine HEV infection. Forty New Zealand White rabbits were randomly assigned to eight groups; groups 1 thru 5 received three immunizations with EPTV-KLH, VKLYTS-KLH, PSRPF-KLH, EPTVKLYTS-KLH, or EPTVKLYTSPSRPF-KLH, respectively; group 6 received truncated swine HEV ORF2 protein (sp239), and group 7 received phosphate-buffered saline. After an intravenous swine HEV challenge, all group 7 rabbits exhibited viremia and fecal virus shedding by 2–4 weeks post challenge (wpc), seroconversion by 4–9 wpc, elevated alanine aminotransferase (ALT) at 2 wpc, and severe liver lymphocytic venous periphlebitis. Only 1–2 rabbits/group in groups 1–4 exhibited delayed viremia, fecal shedding, seroconversion, increased ALT levels, and slight liver lymphocytic venous periphlebitis; groups 5–6 showed no pathogenic effects. Collectively, these results demonstrate that immunization with a polypeptide containing three genotype 4 HEV ORF2 neutralizing epitopes completely protected rabbits against swine HEV infection.

In vivo metabolomic and lipidomic response of healthy humans to intravenous lipopolysaccharide challenge

IntroductionAcute inflammation is a complex protective response to injury or infection. However, systemic hyperinflammatory states can lead to septic shock. Lipopolysaccharide (LPS) is a component of gram‐negative bacteria that is widely used for inducing inflammatory responses in animal models. However, many of the critical molecular networks involved in the LPS response in humans remain largely unknown.ObjectiveTo better characterize the molecular underpinnings of acute inflammation in humans through real‐time biochemical and network appraisals of in vivo challenge with LPS.MethodsHealthy men were intravenously injected with 0.6 ng/kg LPS at Pennsylvania State University. Plasma markers of inflammation (IL‐6, TNFα, and CRP) were measured prior to and 1, 2, 4, 8, 24, and 72 h post injection. Untargeted metabolomic and lipidomic profiling using liquid chromatography tandem mass spectrometry was conducted on the plasma from 10 men. Deuterated internal standards (SPLASH, Avanti Polar Lipids) were added to plasma to facilitate semi‐quantitative analysis of individual lipid molecular species. Statistics were performed in R (version 1.1.463) and Microsoft Excel (version 16.30).ResultsOf the 1847 metabolites reliably detected, 265 remained significant (FDR‐adjusted p < 0.05) after analysis. Of these metabolites, 197 increased, 51 decreased, and 17 both increased and decreased (depending on the point in the time course). Both metabolomics and lipidomics revealed that molecular species of lipid classes including phospholipids (PL), lyso‐PLs, sphingolipids (SL), diglycerides (DG), and triglycerides (TG) had largest number of metabolites altered after LPS challenge. Notably, levels of 50 lyso‐PLs including lyso‐phosphatidylcholine (PC) and lyso‐phosphatidylethanolamine (PE) molecular species were increased in plasma. Additionally, there were significant elevations in certain PL molecular species representing PC, PE, phosphatidylserine, and phosphatidylinositol. Levels of 29 molecular species of SL increased with the majority representing sphingomyelin and ceramide classes. Neutral lipids including DG and TG were also markedly elevated. Pathway analyses highlighted glycerophospholipid metabolism (p < 0.0001) and sphingolipid metabolism (p < 0.001) as highly significant. These data also suggest the activation of multiple lipases including phospholipase A2, phospholipase C and phospholipase D play a critical role in the inflammatory response induced by LPS.DiscussionIntravenous LPS injection profoundly alters lipid metabolism in healthy adult men. These data may facilitate the identification of biochemical lipid networks and the development of biomarkers associated with inflammatory health/disease status.Support or Funding InformationFunding source: NIH R01 AT008621

PD47-05 REGULATORY T CELLS PLAY A KEY ROLE IN BLADDER CANCER DEVELOPMENT

You have accessJournal of UrologyBladder Cancer: Basic Research & Pathophysiology IV (PD47)1 Apr 2020PD47-05 REGULATORY T CELLS PLAY A KEY ROLE IN BLADDER CANCER DEVELOPMENT Karen Wheeler*, Niannan Ji, Neelam Mukherjee, and Robert Svatek Karen Wheeler*Karen Wheeler* More articles by this author , Niannan JiNiannan Ji More articles by this author , Neelam MukherjeeNeelam Mukherjee More articles by this author , and Robert SvatekRobert Svatek More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000934.05AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Regulatory T cells (Treg) are vital in the development and maintenance of immune tolerance. They function to dampen immune responses and their dysfunction leads to autoimmune disease. Treg are known to play key roles in the development of cancers including lung, breast, head and neck, and others. They are believed to aid the tumors in immune evasion. In bladder cancer (BCa), clinical studies have shown an increase in Treg in patients’ tumors or peripheral blood correlates with a worse prognosis. Herein we determine whether Treg play a key role in the development of BCa. METHODS: Female wild type C57BL/6 mice or transgenic DEREG mice (express a diptheria toxin [DT] receptor whenever Foxp3, the driver of a Treg phenotype, is expressed) were used. Metastatic cancer was induced by injecting 0.5 x 106 MB49 bladder tumor cells via tail vein into mice on the day of surgery. Orthotopic (bladder) cancer was induced by catheterizing the bladders of female mice and injecting poly-L-lysine followed by 0.08x106 MB49 cells at day 0. Treg were depleted in DEREG mice with administration of 50g/kg DT given intraperitoneally every 4 days. Mice were sacrificed at days 21-26 and bladders, lungs, and bladder draining lymph nodes (BLN) were harvested for weight and flow cytometric analysis. RESULTS: In mice that received both orthotopic and intravenous bladder tumor challenge, Treg were increased in the bladder tumors but not the lymph nodes or lung (Fig 1). In DEREG mice challenged with orthotopic BCa, depletion of Treg with DT administration abrogated the development of BCa (Fig 2A). Additionally, Treg depleted mice had an increase in the number and percentage of antigen specific CD8+ T cells in the bladder draining lymph nodes as well as an increase in activated CD4+ T cells (Fig 2B). CONCLUSIONS: Regulatory T cells are necessary for BCa development in the orthotopic model of BCa. Treg appear to function in an antigen-specific manner, but pan-T cell activation cannot be excluded. Development of immunotherapy targeting Treg in the bladder may represent a novel cancer therapeutic. Source of Funding: AUA Care Foundation Award, CPRIT Training Grant © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e927-e927 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Karen Wheeler* More articles by this author Niannan Ji More articles by this author Neelam Mukherjee More articles by this author Robert Svatek More articles by this author Expand All Advertisement PDF downloadLoading ...

Long-Term Delivery of an Anti-SIV Monoclonal Antibody With AAV.

Long-term delivery of anti-HIV monoclonal antibodies using adeno-associated virus (AAV) holds promise for the prevention and treatment of HIV infection. We previously reported that after receiving a single administration of AAV vector coding for anti-SIV antibody 5L7, monkey 84-05 achieved high levels of AAV-delivered 5L7 IgG1 in vivo which conferred sterile protection against six successive, escalating dose, intravenous challenges with highly infectious, highly pathogenic SIVmac239, including a final challenge with 10 animal infectious doses (1). Here we report that monkey 84-05 has successfully maintained 240–350 μg/ml of anti-SIV antibody 5L7 for over 6 years. Approximately 2% of the circulating IgG in this monkey is this one monoclonal antibody. This monkey generated little or no anti-drug antibodies (ADA) to the AAV-delivered antibody for the duration of the study. Due to the nature of the high-dose challenge used and in order to rule out a potential low-level infection not detected by regular viral loads, we have used ultrasensitive techniques to detect cell-associated viral DNA and RNA in PBMCs from this animal. In addition, we have tested serum from 84-05 by ELISA against overlapping peptides spanning the whole envelope sequence for SIVmac239 (PepScan) and against recombinant p27 and gp41 proteins. No reactivity has been detected in the ELISAs indicating the absence of naturally arising anti-SIV antibodies; moreover, the ultrasensitive cell-associated viral tests yielded no positive reaction. We conclude that macaque 84-05 was effectively protected and remained uninfected. Our data show that durable, continuous antibody expression can be achieved after one single administration of AAV and support the potential for lifelong protection against HIV from a single vector administration.

Soft Tissue Infection in Intravenous Drug Users-Current Challenges

Skin and soft tissue infections (SSTI) are the most common infections encountered in community and healthcare settings. There are different risk factors associated with SSTI including trauma, surgery, skin disease, immune defects and injection drug usage. Intravenous drug users (IDU) are frequently susceptible to SSTI due to unsafe injection practices, sharing of needles and low immunity. Intravenous drug usage is most common in young and homeless people globally. Although Staphylococcus aureus and Streptococcus pyogenes are the commonest pathogens however there are serious infections caused by rare pathogens such as botulism by Clostridium botulinum and tetanus by Clostridium Tetni. Prompt diagnosis and accurate management at the healthcare level will help in alleviating the symptoms and improve the outcomes. The continuous education and enhancing the implementation of prevention strategies are the responsibilities of local and national government to reduce the harmful drug use. In this review we are addressing the current challenges associated with causative pathogens for SSTI in IDU and their management and preventive strategies.

Rapid changes in neuroendocrine regulation may contribute to reversal of type 2 diabetes after gastric bypass surgery

ObjectiveTo explore the role of hormones and the autonomic nervous system in the rapid remission of diabetes after Roux-en-Y Gastric Bypass (RYGB).Research design and methodsNineteen obese patients with type 2 diabetes, 7 M/12 F, were randomized (2:1) to RYGB or standard-of-care medical treatment (control). At baseline and 4 and 24 weeks post surgery, fasting blood sampling, OGTT, intravenous arginine challenge, and heart-rate variability (HRV) assessments were performed.ResultsAt both 4 and 24 weeks post-RYGB the following effects were found: arginine-stimulated insulin secretion was reduced. GLP-1, GIP, and glucagon rise during OGTT was enhanced. IGF-1 and GH levels increased. In addition, total HRV and spectral components PLF (power of low frequency) and PHF (power of high frequency) increased. At 4 weeks, morning cortisol was lower than baseline and 24 weeks. At 24 weeks, NEFA levels during OGTT, and the PLF/PHF ratio decreased. None of these changes were seen in the control group.ConclusionsThere were rapid changes within 4 weeks after RYGB: signs of enhanced parasympathetic nerve activity, reduced morning cortisol, and enhanced incretin and glucagon responses to glucose. The findings suggest that neurohormonal mechanisms can contribute to the rapid improvement of insulin resistance and glycemia following RYGB in type 2 diabetes.

Pharmacological evaluation of a novel corticotropin‐releasing factor 1 receptor antagonist T‐3047928 in stress‐induced animal models in a comparison with alosetron

The major symptoms of irritable bowel syndrome (IBS) are changes in bowel habits and abdominal pain. Psychological stress is the major pathophysiological components of IBS. Corticotropin-releasing factor (CRF) is a well-known integrator in response to psychological stress. In this study, a novel CRF1 receptor antagonist T-3047928 was evaluated in stress-induced IBS models of rats to explore its potency for IBS. Plasma adrenocorticotropic hormone (ACTH) levels after intravenous oCRH challenge were measured as a pharmacodynamic marker. Efficacies of oral T-3047928 were compared with oral alosetron, a 5-HT3 antagonist, on conditioning fear stress (CFS)-induced defecation, restraint stress (RS)-induced acute visceral pain, specific alteration of rhythm in temperature (SART) stress-induced chronic visceral pain, and normal defecation. T-3047928 (1-10mg/kg, p.o.) demonstrated a dose-dependent inhibition on oCRH-induced ACTH secretion. In disease models, T-3047928 suppressed fecal pellet output induced by CFS and improved both acute and chronic visceral hypersensitivity induced by RS and SART stress, respectively. Alosetron was also efficacious in stress-induced defecation and visceral pain models at 1 and 10mg/kg, respectively. Alosetron, however, also suppressed normal defecation at lower those. On the other hand, T-3047928 did not change normal defecation even at higher dose than those in disease models. T-3047928 is an orally active CRF1 antagonist that demonstrated potent inhibitory effects in stress-associated IBS models with no effect on normal defecation. Therefore, it is suggested that T-3047928 may have a potency as a novel option for IBS-D therapy with minimal constipation risk.

Intravenous aspirin challenge as a diagnosis of nonsteroidal anti-inflammatory drugs hypersensitivity.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a major cause of drug-induced hypersensitivity, called "NSAID hypersensitivity". A confirmative diagnosis is necessary for ensuring drug safety and finding alternative drugs. No reliable test other than direct challenge is diagnostic. An intravenous (IV) aspirin challenge has rarely been tried. To assess the safety and efficacy of the aspirin IV provocation test. A retrospective and descriptive study in a hospital. Clinical data were reviewed in patients who had aspirin IV provocation test with lysine aspirin. In 71 patients suspected of having NSAID hypersensitivity, aspirin IV provocation test was performed. Most provocations were performed on the same day. Forty-three (60.6%) showed a positive response to the challenge. The positive reactions were rescued mostly by antihistamines or glucocorticoids and rarely with bronchodilators and epinephrine. Three patients who showed a negative response to the aspirin challenge were shown to have single-NSAID hypersensitivity. For confirmation of NSAID hypersensitivity in these patients, the sensitivity of the IV aspirin provocation test was 93.5%. Aspirin IV provocation test with lysine aspirin on the same day is safe and efficacious for diagnosing NSAID hypersensitivity.

Non-β-Lactam Antibiotic Hypersensitivity Reactions.

Antibiotics are among the most common prescriptions in children, and non-β-lactam antibiotics (NBLAs) account for almost half of those prescribed in Australian pediatric hospitals. Despite this, data on NBLA hypersensitivity in children are limited. This study describes reported hypersensitivity reactions to NBLAs in children and the results of allergy evaluation. Children with a suspected NBLA allergy who had skin testing and/or an intravenous or oral challenge test (OCT) between May 2011 and June 2018 were included. Patients were excluded if they were >18 years old or did not complete the allergy evaluation for any reason other than allergic reaction. Over the 7-year study period, 141 children had 150 allergy evaluations of 15 different NBLAs. The median time from the initial reported reaction to allergy evaluation was 1.9 (range 0.1-14.9) years. Overall, 27 of the 150 (18.0%) challenge tests to NBLAs had positive results, with the rate of positive OCT results being highest for trimethoprim-sulfamethoxazole (15 of 46; 32.6%) and macrolides (8 of 77; 10.4%). Although 4 children reported initial anaphylactic reactions, no patients had severe symptoms on rechallenge or required adrenaline. Of the challenges that had positive results, the majority of children (23 of 27; 85.2%) had symptoms on repeat challenge similar to those that were initially reported. Overall, 8 of 10 children with NBLA allergy could be delabeled. On average, patients waited 1.9 years to be rechallenged. Timely access to allergy evaluation to delabel these patients is needed to preserve first-line antibiotics.

Editorial introductions

Editorial introductions

Vaccine against peanut allergy based on engineered virus-like particles displaying single major peanut allergens

Peanut allergy is a severe and increasingly frequent disease with high medical, psychosocial, and economic burden for affected patients and wider society. Acausal, safe, and effective therapy is not yet available. We sought to develop an immunogenic, protective, and nonreactogenic vaccine candidate against peanut allergy based on virus-like particles (VLPs) coupled to single peanut allergens. To generate vaccine candidates, extracts of roasted peanut (Ara R) or the single allergens Ara h 1 or Ara h 2 were coupled to immunologically optimized Cucumber Mosaic Virus-derived VLPs (CuMVtt). BALB/c mice were sensitized intraperitoneally with peanut extract absorbed to alum. Immunotherapy consisted of a single subcutaneous injection of CuMVtt coupled to Ara R, Ara h 1, or Ara h 2. The vaccines CuMVtt-Ara R, CuMVtt-Ara h 1, and CuMVtt-Ara h 2 protected peanut-sensitized mice against anaphylaxis after intravenous challenge with the whole peanut extract. Vaccines did not cause allergic reactions in sensitized mice. CuMVtt-Ara h 1 was able to induce specific IgG antibodies, diminished local reactions after skin prick tests, and reduced the infiltration of the gastrointestinal tract by eosinophils and mast cells after oral challenge with peanut. The ability of CuMVtt-Ara h 1 to protect against challenge with the whole extract was mediated by IgG, as shown via passive IgG transfer. FcγRIIb was required for protection, indicating that immune complexes with single allergens were able to block the allergic response against the whole extract, consisting of a complex allergen mixture. Our data suggest that vaccination using single peanut allergens displayed on CuMVtt may represent a novel therapy against peanut allergy with a favorable safety profile.

Evaluation of the allergenicity of ω5-gliadin-deficient Hokushin wheat (1BS-18) in a wheat allergy rat model

We previously developed Hokushin wheat line as a hypoallergenic wheat lacking ω5-gliadin (1BS-18), a major allergen for wheat-dependent exercise-induced anaphylaxis. However, the allergenicity of 1BS-18 has not been understood completely. In this study, we evaluated the allergenicity of 1BS-18 such as anaphylactic elicitation ability and sensitization ability using rats sensitized with ω5-gliadin or glutens prepared from Hokushin (Hokushin gluten) or 1BS-18 (1BS-18 gluten). Rats were sensitized by intraperitoneal administration of ω5-gliadin, Hokushin gluten or 1BS-18 gluten. Immunoglobulin E-mediated systemic anaphylaxis was evaluated by measuring changes in rectal temperature for 30 min after intravenous challenge with ω5-gliadin or the test glutens in unsensitized rats or rats sensitized with ω5-gliadin or the test glutens. In ω5-gliadin-sensitized rats, intravenous challenge with ω5-gliadin or Hokushin gluten significantly decreased the rectal temperature at 30 min after challenge while challenge with 1BS-18 gluten did not reduce the rectal temperature. Furthermore, intravenous challenge with ω5-gliadin significantly decreased the rectal temperature in rats sensitized with Hokushin gluten or 1BS-18 gluten. However, the reduced degree observed in 1BS-18 gluten-sensitized rats was smaller than that in Hokushin gluten-sensitized rats. In conclusion, 1BS-18 elicited no allergic reaction in ω5-gliadin-sensitized rats and had less sensitization ability for ω5-gliadin than that of Hokushin wheat.

Reduction of peak viremia by an integration‐defective SIV proviral DNA vaccine in rhesus macaques

An integrase-defective SIV (idSIV) vaccine delivered by a DNA prime and viral particle boost approach can suppress viral loads (VLs) during the acute infection stage after intravenous SIVmac239 challenge. This study investigated how idSIV DNA and viral particle immunization alone contributed to the suppression of VLs in Chinese rhesus macaques after SIV challenge. Two macaques were immunized with idSIV DNA five times and two macaques were immunized with idSIV viral particles three times. Cellular and humoral immune responses were measured in the vaccinated macaques after immunization. The VLs and CD4+ T cell counts were monitored for 28 weeks after the intravenous SIVmac239 challenge. The SIV-specific T cell responses were only detected in the DNA-vaccinated macaques. However, binding and neutralizing antibodies against autologous and heterologous viruses were moderately better in macaques immunized with viral particles than in macaques immunized with DNA. After the challenge, the mean peak viremia in the DNA group was 2.3 logs lower than that in the control group, while they were similar between the viral particle immunization and control groups. Similar CD4+ T cell counts were observed among all groups. These results suggest that idSIV DNA immunization alone reduces VLs during acute infection after SIV challenge in macaques and may serve as a key component in combination with other immunogens as prophylactic vaccines.

Vaccination with the immunoglobulin M-degrading enzyme of Streptococcus suis, IdeSsuis, leads to protection against a highly virulent serotype 9 strain

Vaccination of weaning piglets with the recombinant IgM degrading enzyme of Streptococcus suis (S. suis), rIdeSsuis, elicits protection against disease caused by serotype (cps) 2 infection. In Europe, S. suis cps9 is at least as important as cps2 in causing severe herd problems associated with meningitis, septicemia and arthritis. The objective of this study was to determine humoral and cellular immunogenicities of rIdeSsuis suckling piglet vaccination and to investigate protection against a virulent cps9 strain. Vaccination in the 2nd and 4th week of life with rIdeSsuis and an oil-in-water adjuvant induced seroconversion against IdeSsuis in 13 of 20 vaccinated piglets. In the 5th week, survival of the S. suis cps9 strain was significantly reduced in the blood of prime-booster vaccinated piglets. After a 2nd booster vaccination IdeSsuis-reactive T helper (Th) cells partially producing TNF-α, IL-17A or IFN-ɣ were detectable in rIdeSsuis-vaccinated but not in placebo-treated piglets and frequencies of IdeSsuis-reactive Th cells correlated with α-IdeSsuis–IgG levels. An intravenous challenge, conducted with a cps9 strain of sequence type (ST) 94, led to 89% mortality in placebo-treated piglets due to septicemia and meningitis. In contrast, all rIdeSsuis prime-booster-booster vaccinated littermates survived the challenge despite signs of disease such as fever and lameness. In conclusion, the described rIdeSsuis vaccination induces humoral and detectable IdeSsuis-reactive Th cell responses and leads to protection against a highly virulent cps9 strain.

Effects of maternal supplementation with an injectable trace mineral on subsequent calf performance and inflammatory response1.

Newly weaned, commercial Angus steers [body weight (BW) = 204 ± 19 kg; n = 24; 12 steers from dams administered an injectable trace mineral (MM; Mulimin90) and 12 steers from control (CON) dams] were utilized to determine the effects of maternal supplementation with an injectable trace mineral on the inflammatory response of subsequent steers subjected to a lipopolysaccharide (LPS) challenge at the initiation of a 42-d receiving period. On day -2 steers were weaned, and the following day, shipped 354 km to the Beef Cattle and Sheep Field Laboratory in Urbana, IL. On day 0, steers were administered an intravenous LPS challenge. Body temperature and blood samples were collected from steers prior to LPS administration (0 h) and again at 0.5, 1, 2, 3, 4, 5, and 6 h. Blood samples were analyzed for trace mineral and cortisol at 0 and 2 h and glucose, insulin, LPS-binding protein (LBP), interleukin-1β (IL-1β), interleukin-6 (IL-6), haptoglobin, ceruloplasmin, and fibrinogen at 0, 0.5, 1, 2, 3, 4, 5, and 6 h. Calf BW was collected at trial initiation and subsequently every 14 d. Dry matter intake was collected daily and average daily gain (ADG) and feed efficiency were assessed. Initial plasma Zn tended (P = 0.06) to be greater for MM steers. However, there was no difference (P ≥ 0.31) in trace mineral status or serum cortisol at any other time. Total area under the curve (TAUC) for body temperature was lesser (P > 0.01) for MM steers. Basal LBP concentrations and TAUC for LBP tended (P ≤ 0.10) to be greater for MM steers. Peak concentration of IL-6 tended (P = 0.09) to be reached earlier for CON steers. However, there was no difference (P ≥ 0.11) in glucose, insulin, IL-6, ceruloplasmin, haptoglobin, and fibrinogen concentrations between treatments. Calf performance and feed efficiency did not differ (P ≥ 0.17) between treatments except ADG from day 28 to 42, which was greater (P = 0.03) for CON steers. Maternal supplementation with an injectable trace mineral tended to improve steer plasma Zn status at 0 h and tended to increase basal concentrations of LBP and overall LBP production when steers were administered an LPS challenge. Additionally, MM steers exhibited a more favorable change in body temperature following LPS administration. However, injectable trace mineral supplementation of dams during gestation had minimal to no effect on cytokine and acute-phase protein concentrations, as well as overall calf performance and efficiency during a 42-d receiving period.

Acute Elevations in Cortisol Increase the In Vivo Binding of [11C]NOP-1A to Nociceptin Receptors: A Novel Imaging Paradigm to Study the Interaction Between Stress- and Antistress-Regulating Neuropeptides

BackgroundAn imbalance between neuropeptides that promote stress and resilience, such as corticotropin-releasing factor and nociceptin, has been postulated to underlie relapse in addiction. The objective of this study was to develop a paradigm to image the in vivo interaction between stress-promoting neuropeptides and nociceptin (NOP) receptors in humans. Methods[11C]NOP-1A positron emission tomography was used to measure the binding to NOP receptors at baseline (BASE) and following an intravenous hydrocortisone challenge (CORT) in 19 healthy control subjects. Hydrocortisone was used as a challenge because in microdialysis studies it has been shown to increase corticotropin-releasing factor release in extrahypothalamic brain regions such as the amygdala. [11C]NOP-1A total distribution volume (VT) in 11 regions of interest were measured using a 2-tissue compartment kinetic analysis. The primary outcome measure was hydrocortisone-induced ΔVT calculated as (VT CORT − VT BASE)/VT BASE. ResultsHydrocortisone led to an acute increase in plasma cortisol levels. Regional [11C]NOP-1A VT was on average 11% to 16% higher in the post-hydrocortisone condition compared with the baseline condition (linear mixed model, condition, p = .005; region, p < .001; condition × region, p < .001). Independent Student's t tests in all regions of interest were statistically significant and survived multiple comparison correction. Hydrocortisone-induced ΔVT was significantly negatively correlated with baseline VT in several regions of interest. ConclusionsHydrocortisone administration increases NOP receptor availability. Increased NOP in response to elevated cortisol might suggest a compensatory mechanism in the brain to counteract corticotropin-releasing factor and/or stress. The [11C]NOP-1A and hydrocortisone imaging paradigm should allow for the examination of interactions between stress-promoting neuropeptides and NOP in addictive disorders.

Effects of recombinant bovine interleukin-8 (rbIL-8) treatment on health, metabolism, and lactation performance in Holstein cattle IV: Insulin resistance, dry matter intake, and blood parameters

We have shown in 2 independent studies that cows who received recombinant bovine interleukin-8 (rbIL-8) administered intrauterinely shortly after parturition have a significant and long-lasting increase in milk yield. In the present study, we hypothesized that the increased milk production associated with rbIL-8 treatment is a consequence of increased postpartum dry matter intake (DMI) and orchestrated homeorhetic changes that prioritize milk production. Cows were enrolled into 1 of 3 treatment groups: those assigned to the control group (CTR; n = 70) received an intrauterine (IU) administration of 500 mL of Dulbecco's phosphate-buffered saline (DPBS) solution and 1 mL of DPBS solution intravenously (IV; jugular vein), those assigned to the rbIL-8 IV group (rbIL8-IV, n = 70) received an IV injection of 167 μg of rbIL-8 and 500 mL of DPBS solution IU, and cows assigned to the rbIL-8 IU group (rbIL8-IU, n = 70) received an IU administration with 1,195 μg of rbIL-8 diluted in 499.5 mL of DPBS solution and 1 mL of DPBS solution IV. Animals were housed in a tiestall from calving to 30 d in milk (DIM) to measure DMI. Blood samples were collected daily from calving to 7 DIM and weekly until 28 DIM. Insulin resistance was evaluated using an intravenous glucose tolerance test and intravenous insulin challenge test (IVICT) in a subgroup of cows (n = 20/treatment) at 10 and 11 DIM, respectively. Additionally, liver biopsy samples were taken at 14 DIM from the same subgroup of cows to measure triglyceride levels and cell proliferation and apoptosis. Cows treated with rbIL8-IU produced more milk (CTR = 36.9 ± 1.5; rbIL8-IU = 38.5 ± 1.5; rbIL8-IV = 36.6 ± 1.5 kg/d), energy-corrected milk (CTR = 42.9 ± 0.9; rbIL8-IU = 46.1 ± 0.8; rbIL8-IV = 43.7 ± 0.9 kg/d), and fat-corrected milk (CTR = 44.3 ± 0.9; rbIL8-IU = 47.8 ± 0.9; rbIL8-IV = 45.2 ± 0.9 kg/d) yields when compared with CTR cows, and no differences were observed between rbIL8-IV and CTR cows. The administration of rbIL8-IU significantly increased DMI compared with CTR (CTR = 18.8 ± 0.3; rbIL8-IU = 19.9 ± 0.3; rbIL8-IV = 19.3 ± 0.3 kg/d). Recombinant bIL-8 treatment did not affect glucose, insulin, or fatty acids (i.e., IVICT only) concentrations or their area under the curve in response to an intravenous glucose tolerance test and IVICT when compared with CTR. Moreover, rbIL-8 treatment administered IU or IV increased liver triglyceride levels. Additionally, cows treated with rbIL8-IU tended to have lower odds of developing hyperketonemia (odds ratio = 0.46, 95% confidence interval: 0.19 to 1.10), lower odds of clinical ketosis and displaced abomasum combined (odds ratio = 0.17, 95% confidence interval: 0.03 to 0.89), and lower odds of diseases combined (odds ratio = 0.43, 95% confidence interval: 0.21 to 0.86) when compared with CTR. We conclude that the administration of rbIL8-IU increases DMI, milk production, fat-corrected milk, and energy-corrected milk while improving overall health during the postpartum period. This study supports the use of rbIL-8 administered IU shortly after calving to improve health and production responses in lactating cows.

Fibrotic Encapsulation Is the Dominant Source of Continuous Glucose Monitor Delays.

Continuous glucose monitor (CGM) readings are delayed relative to blood glucose, and this delay is usually attributed to the latency of interstitial glucose levels. However, CGM-independent data suggest rapid equilibration of interstitial glucose. This study sought to determine the loci of CGM delays. Electrical current was measured directly from CGM electrodes to define sensor kinetics in the absence of smoothing algorithms. CGMs were implanted in mice, and sensor versus blood glucose responses were measured after an intravenous glucose challenge. Dispersion of a fluorescent glucose analog (2-NBDG) into the CGM microenvironment was observed in vivo using intravital microscopy. Tissue deposited on the sensor and nonimplanted subcutaneous adipose tissue was then collected for histological analysis. The time to half-maximum CGM response in vitro was 35 ± 2 s. In vivo, CGMs took 24 ± 7 min to reach maximum current versus 2 ± 1 min to maximum blood glucose (P = 0.0017). 2-NBDG took 21 ± 7 min to reach maximum fluorescence at the sensor versus 6 ± 6 min in adipose tissue (P = 0.0011). Collagen content was closely correlated with 2-NBDG latency (R = 0.96, P = 0.0004). Diffusion of glucose into the tissue deposited on a CGM is substantially delayed relative to interstitial fluid. A CGM that resists fibrous encapsulation would better approximate real-time deviations in blood glucose.