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Background: The emergence of novel SARS-CoV-2 variants challenges immunity, particularly among immunocompromised kidney transplant recipients (KTRs). To address this, vaccines have been adjusted to circulating variants. Despite intensive vaccination efforts, SARS-CoV-2 infections surged among KTRs during the Omicron wave, enabling a direct comparison of variant-specific immunity following-vaccination against Omicron BA.4/5 or Omicron infection in KTRs., Methods: 98 SARS-CoV-2 naïve KTRs who had received four vaccine doses were studied. Before and after a 5th antigen exposure, either via the bivalent vaccine composed of ancestral SARS-CoV-2 and Omicron BA.4/5 (29 KTRs) or via natural infection with Omicron (38 BA.4/5, 31 BA.1/2), spike-specific T cells were quantified using Elispot and serum pseudovirus neutralizing activity was assessed against the ancestral Wuhan strain, BA.5 and XBB.1.5., Results: Compared to BA.4/5 vaccination, spike-specific T-cell responses and neutralization activity were higher up to six months post-Omicron infection and reached levels similar to healthy controls. Vaccinated KTRs showed modestly boosted neutralization activity against the Wuhan strain and BA.5, but not XBB.1.5. Baseline immunity correlated with immune responses three months post-vaccination and post-infection, indicating a predictive value for peak immune responses. Tixagevimab/Cilgavimab treatment was associated with robust neutralization of the Wuhan strain, but ineffective against XBB.1.5., Conclusion: The BA.4/5 vaccine improved neutralizing activity against the BA.4/5 variant, but not against the subsequently circulating XBB.1.5 variant in KTRs. Conversely, omicron infection boosted T cells and humoral responses more effectively, showing efficacy against XBB.1.5. These findings suggest that infection-induced immunity associates with greater protection than vaccination against future variants in KTRs., Competing Interests: HG and FK are inventors on patent applications on SARS-CoV-2 neutralizing antibodies filed by the University of Cologne and have received payments from the University of Cologne for licensed antibodies. LK received consulting fees or payment/honoraria from ViiV, Theratechnologies, Gilead and MSD. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2025 Tometten, Brandt, Schlotz, Stumpf, Landmann, Kantauskaite, Lamberti, Hillebrandt, Müller, Kittel, Ivens, Gruell, Voges, Schaal, Lübke, Königshausen, Rump, Klein, Stegbauer and Timm.)

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important prophylactic measure in kidney transplant recipients (KTRs), but the immune response is often impaired. Here, we examined the T-cell immune response against SARS-CoV-2 in 148 KTRs after 3 or 4 vaccine doses, including 35 KTRs with subsequent SARS-CoV-2 infection. The frequency of spike-specific T cells was lower in KTRs than in immunocompetent controls and was correlated with the level of spike-specific antibodies. Positive predictors for detection of vaccine-induced T cells were detection of spike-specific antibodies, heterologous immunization with messenger RNA and a vector vaccine, and longer time after transplantation. In vaccinated KTRs with subsequent SARS-CoV-2 infection, the T-cell response was greatly enhanced and was significantly higher than in vaccinated KTRs without SARS-CoV-2 infection. Overall, the data show a correlation between impaired humoral and T-cell immunity to SARS-CoV-2 vaccination and provide evidence for greater robustness of hybrid immunity in KTRs., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Modification of vaccination strategies is necessary to improve the immune response to SARS-CoV-2 vaccination in kidney transplant recipients (KTRs). This multicenter observational study analyzed the effects of the third SARS-CoV-2 vaccination in previously seronegative KTRs with the focus on temporary mycophenolate mofetil (MMF) dose reduction within propensity matched KTRs. 56 out of 174 (32%) previously seronegative KTRs became seropositive after the third vaccination with only three KTRs developing neutralizing antibodies against the omicron variant. Multivariate logistic regression revealed that initial antibody levels, graft function, time after transplantation and MMF trough levels had an influence on seroconversion (P < .05). After controlling for confounders, the effect of MMF dose reduction before the third vaccination was calculated using propensity score matching. KTRs with a dose reduction of ≥33% showed a significant decrease in MMF trough levels to 1.8 (1.2-2.5) μg/ml and were more likely to seroconvert than matched controls (P = .02). Therefore, a MMF dose reduction of 33% or more before vaccination is a promising approach to improve success of SARS-CoV-2 vaccination in KTRs., (© 2022 The Authors. Clinical Transplantation published by John Wiley & Sons Ltd.)

We provide follow-up data on the humoral immune response after COVID-19 vaccinations of two distinct cohorts aged below 60 and over 80 years to screen for age-related differences in the longevity and magnitude of the induction of the antibody responses post booster-vaccinations. While anti-SARS-CoV-2 spike-specific IgG and neutralization capacity waned rapidly after the initial vaccination schedule, additional boosters highly benefitted the humoral immune responses especially in the elderly cohort, including the neutralization of Omikron variants. Thus, adjusted COVID-19 booster vaccination schedules are an appropriate tool to overcome limitations in the success of vaccinations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Müller, Andrée, Moskorz, Drexler, Hauka, Ptok, Walotka, Grothmann, Hillebrandt, Ritchie, Peter, Walker, Timm, Adams and Schaal.)

Kidney transplant recipients (KTRs) are extremely vulnerable to SARS-CoV-2 infection and show an impaired immune response to SARS-CoV-2 vaccination. We analyzed factors related to vaccination efficiency in KTRs. In a multicenter prospective observational study (NCT04743947), IgG antibodies levels against SARS-CoV-2 spike S1 subunit and their neutralization capacity after SARS-CoV-2 vaccination were analyzed in 225 KTRs and compared to 176 controls. After the vaccination, 56 (24.9%) KTRs became seropositive of whom 68% had neutralizing antibodies. This immune response was significantly lower compared to controls (239 [78-519] BAU/ml versus 1826 [560-3180] BAU/ml for KTRs and controls, p < .0001). The strongest predictor for an impaired response was mycophenolate mofetil (MMF) treatment. Multivariate regression analysis revealed that MMF-free regimen was highly associated with seroconversion (OR 13.25, 95% CI 3.22-54.6; p < .001). In contrast, other immunosuppressive drugs had no significant influence. 187 out of 225 KTRs were treated with MMF of whom 26 (13.9%) developed antibodies. 23 of these seropositive KTRs had a daily MMF dose ≤1 g. Furthermore, higher trough MMF concentrations correlated with lower antibody titers (R -0.354, p < .001) supporting a dose-dependent unfavorable effect of MMF. Our data indicate that MMF dose modification could lead to an improved immune response., (© 2021 The Authors. American Journal of Transplantation published by Wiley Periodicals LLC on behalf of The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has led to the development of various vaccines. Real-life data on immune responses elicited in the most vulnerable group of vaccinees older than age 80 years old are still underrepresented despite the prioritization of the elderly in vaccination campaigns., Methods: We conducted a cohort study with 2 age groups, young vaccinees below the age of 60 years and elderly vaccinees over the age of 80 years, to compare their antibody responses to the first and second dose of the BNT162b2 coronavirus disease 2019 vaccination., Results: Although the majority of participants in both groups produced specific immunoglobulin G antibody titers against SARS-CoV-2 spike protein, titers were significantly lower in elderly participants. Although the increment of antibody levels after the second immunization was higher in elderly participants, the absolute mean titer of this group remained lower than the <60 years of age group. After the second vaccination, 31.3% of the elderly had no detectable neutralizing antibodies in contrast to the younger group, in which only 2.2% had no detectable neutralizing antibodies., Conclusions: Our data showed differences between the antibody responses raised after the first and second BNT162b2 vaccination, in particular lower frequencies of neutralizing antibodies in the elderly group. This suggests that this population needs to be closely monitored and may require earlier revaccination and/or an increased vaccine dose to ensure stronger long-lasting immunity and protection against infection., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Patients with kidney failure on dialysis or after renal transplantation have a high risk for severe COVID-19 infection, and vaccination against SARS-CoV-2 is the only expedient prophylaxis. Generally, immune responses are attenuated in patients with kidney failure, however, systematic analyses of immune responses to SARS-CoV-2 vaccination in patients on dialysis and in kidney transplant recipients (KTRs) are still needed., Methods: In this prospective, multicentric cohort study, antibody responses to COVID-19 mRNA vaccines (BNT162b2 [BioNTech/Pfizer] or mRNA-1273 [Moderna]) were measured in 32 patients on dialysis and in 28 KTRs. SARS-CoV-2-specific antibodies and neutralization capacity were evaluated and compared with controls ( n =78) of a similar age range., Results: After the first vaccination, SARS-CoV-2-specific antibodies were nearly undetectable in patients with kidney failure. After the second vaccination, 93% of the controls and 88% of patients on dialysis but only 37% of KTRs developed SARS-CoV-2-specific IgG above cutoff. Moreover, mean IgG levels were significantly lower in KTRs (54±93 BAU/ml) compared with patients on dialysis (503±481 BAU/ml; P <0.01). Both KTRs and patients on dialysis had significantly lower IgG levels compared with controls (1992±2485 BAU/ml; P <0.001 and P <0.01, respectively). Importantly, compared with controls, neutralizing antibody titers were significantly lower in KTRs and patients on dialysis. After the second vaccination, 76% of KTRs did not show any neutralization capacity against SARS-CoV-2, suggesting impaired seroprotection., Conclusions: Patients with kidney failure show a significantly weaker antibody response compared with controls. Most strikingly, only one out of four KTRs developed neutralizing antibodies against SARS-CoV-2 after two doses of vaccine. These data suggest that vaccination strategies need modification in KTRs and patients on dialysis. Clinical Trial registry name and registration number: Vaccination Against COVID-19 in Chronic Kidney Disease, NCT04743947., Competing Interests: L.C. Rump reports having consultancy agreements with, and receiving honoraria from, Bayer, Boehringer, Medtronic, and ReCor. M. Schmitz reports receiving honoraria from Daiichi-Sankyo. J. Stegbauer reports having other interests in/relationships with American Heart Association High Blood Pressure, German Society of Nephrology, and German Society of Hypertension; receiving honoraria from AstraZeneca, Bayer Life Science, and Boehringer; serving on the editorial board of Experimental and Clinical Endocrinology & Diabetes and Kidney360; and receiving research funding from German Research Foundation. All remaining authors have nothing to disclose., (Copyright © 2021 by the American Society of Nephrology.)

Introduction: Increased admissions occur in small animal veterinary emergency clinics during some holidays, and some of the increased caseload is due to ingestion of toxic substances. This report documents zinc toxicosis contributing to the death of a dog after ingestion of holiday tinsel garland., Case Study: A mature boxer dog presented with a 4-day history of vomiting and diarrhea. Radiodense foreign material was detected in the stomach and removed via gastrotomy. The patient clinically worsened over the next several days with evidence of hemolytic anemia, severe hypernatremia, and an elevated WBC count with a suspected dehiscence of the surgical site and acute renal failure. The serum zinc concentration was moderately elevated. Postmortem findings included surgical dehiscence from the gastrotomy and enterotomy sites, hepatic extramedullary hematopoiesis, hemoglobinuric nephrosis, and pancreatic fibrosis. The foreign material removed from the stomach also contained zinc., Discussion: Ingestion of holiday tinsel garland made from metal-coated plastic film has not previously been implicated in zinc toxicosis. Zinc toxicosis has a good prognosis in veterinary medicine when diagnosed and treated promptly, but the unique source of zinc in this dog contributed to the delay in diagnosis and grave outcome in this case.

Blood lead (Pb) is used to diagnose Pb poisoning and exposure in cattle, but there are limited data comparing circulating Pb with concentrations in beef from the same cattle. This study determines whether there is a correlation between blood Pb and tissue Pb concentrations in accidentally exposed cattle. Pb analyses were carried out on ante-mortem blood and post-mortem tissues (including, if available, brain, liver, skeletal muscle, bone, gastrointestinal contents and kidney, and also foetal tissues from one cow) collected from 13 cattle known to have accidental Pb exposure and from three control cows with no known exposure. Variables from cattle were analysed statistically using a Shapiro-Wilk normality test and non-parametric descriptive and association statistics. Blood Pb from exposed cattle rank-correlated with liver, bone and kidney Pb concentrations, but not with the Pb concentrations of brain, skeletal muscle or gastrointestinal contents. The lowest blood Pb concentration associated with a detectable skeletal muscle Pb concentration (> 0.1 mg kg - 1 dry matter) was 4.57 μg dl -1 . Based on these findings, we recommend that cattle with blood Pb > 2.5 μg dl -1 be withheld from slaughter and that liver, bone and kidney from all cattle with known Pb exposure be withheld from the human food chain.

The goal of the current study was to determine the range of blood selenium concentrations in goats in New York State that were fed adequately supplemented diets. Blood samples from mature, juvenile, and neonatal goats from commercial farms, 2 dairy and 2 meat producers, were analyzed via graphite-furnace atomic absorption spectroscopy. Feed samples were analyzed by using inductively coupled argon plasma optical emission spectroscopy to confirm that dietary selenium concentrations were adequate. The ranges of blood selenium concentration obtained were 9.1-49.9 microg/dl for mature goats, 7.6-37.5 microg/dl for juveniles, and 9.7-40.7 microg/dl for neonates.

The current study compared the LeadCare(R) II test kit system with graphite-furnace atomic absorption spectrometry for blood lead (Pb) analysis in 56 cattle accidentally exposed to Pb in the field. Blood Pb concentrations were determined by LeadCare II within 4 hr of collection and after 72 hr of refrigeration. Blood Pb concentrations were determined by atomic absorption spectrometry, and samples that were coagulated (n = 12) were homogenized before analysis. There was strong rank correlation (R(2) = 0.96) between atomic absorption and LeadCare II (within 4 hr of collection), and a conversion formula was determined for values within the observed range (3-91 mcg/dl, although few had values >40 mcg/dl). Median and mean blood pb concentrations for atomic absorption were 7.7 and 15.9 mcg/dl, respectively; for LeadCare II, medians were 5.2 mcg/dl at 4 hr and 4.9 mcg/dl at 72 hr, and means were 12.4 and 11.7, respectively. LeadCare II results at 4 hr strongly correlated with 72 hr results (R(2) = 0.96), but results at 72 hr were lower (P < 0.01). There was no significant difference between coagulated and uncoagulated samples run by atomic absorption. Although there have been several articles that compared LeadCare with other analytical techniques, all were for the original system, not LeadCare II. The present study indicated that LeadCare II results correlated well with atomic absorption over a wide range of blood Pb concentrations and that refrigerating samples for up to 72 hr before LeadCare II analysis was acceptable for clinical purposes.

A method for determination of riboflavin in animal feeds using liquid chromatography (LC) was developed for feed samples fortified with riboflavin at 1 mg/lb or greater (up to 10,000 mg/lb). Feed samples were extracted in 0.1 N HCl with heating on a steam bath for 30 min, followed immediately by mechanical shaking for 30 min. Sample extracts were diluted to target volume with 2% acetic acid and filtered; riboflavin was determined by LC on a reversed-phase C18 column with 2% acetic acid-acetonitrile (85 + 15) mobile phase for separation and fluorescence detection with excitation at 460 nm and emission at 530 nm. The extraction was compared with that of the AOAC Official Method for riboflavin in food and feed premixes. The 2 method extractions were not significantly different from each other at the 95% confidence level. The developed method also had good linearity over 4 orders of magnitude, recovery of 95-99% from spiked feed samples, a limit of detection of riboflavin at 0.00034 microg/mL in solution, a limit of quantitation of 0.023 mg/lb in feed, and good ruggedness.

Potato pulp, one of the agricultural waste products obtained in high quantities during starch production, contains starch, cellulose, hemicelluloses, pectin, proteins, free amino acids and salts. It exhibits physical and physicochemical properties of a typical colloid. It is mainly used, in a dried and pelleted form, as cattle feed. Its autochthonic microbial flora (bacteria, fungi) was identified and studied with a view towards the degradative potential of the microorganisms and ways of conserving the pulp for subsequent technical applications; 33 isolates (28 bacteria, 4 fungi, 1 yeast), belonging to 15 genera were characterized. Biological conservation was possible at very low oxygen pressure, brought about by the autochthonic anaerobic microorganisms causing acidification. Chemical conservation was achieved with sorbic acid. By treatment with hot water vapour under pressure (autoclaving), followed by a pressure release procedure, intact cells in the pulp (both potato cells and microorganisms, not spores) were destroyed, and their contents and wall fragments were set free. This process resulted in low drying costs and was a prerequisite for the production of a powder that can be used as glue or as animal feed.