Increase In Titer Research Articles

Serological assessment of the durability of vaccine-mediated protection against SARS-CoV-2 infection.

Abstract Virus-specific neutralizing antibodies are generally accepted as a correlate of protection against infection, though many questions remain about which components of the immune response protect against SARS-CoV-2 infection. We longitudinally measured Spike receptor binding domain (RBD)-specific serum IgG and nucleocapsid protein (NP)-specific serum IgG in a human cohort immunized with the Pfizer BNT162b2 vaccine. Serum samples were collected and stored at −80 °C. Antibody titers were quantitated using an endpoint dilution ELISA and reported as inverse titers. A four-fold or greater increase in NP-specific antibody titers was used as serological marker of clinical infection at some point prior to the sample collection. Using the RBD-specific IgG titer measured in participants’ serum collected prior to seroconversion for NP, we were able to calculate a protective threshold titer for RBD-specific IgG. We calculated the rate of decay of antibodies in participants who did not exhibit a four-fold increase in NP-specific IgG, i.e. had no serological evidence of infection, and found that, on average, the RBD-specific IgG response waned below the protective threshold by four months following vaccination. These data highlight the need for a more durable immune response to vaccination which may require different adjuvants, dosages, or vaccination schedules. This work was supported by The Robert M. Hearin Foundation, The Bower Foundation, and James L. Barksdale.

Exorista sorbillans (Diptera: Tachinidae) parasitism shortens host larvae growth duration by regulating ecdysone and juvenile hormone titers in Bombyx mori (Lepidoptera: Bombycidae).

The tachinid fly, Exorista sorbillans, is a notorious ovolarviparous endoparasitoid of the silkworm, Bombyx mori, causing severe damage to silkworm cocoon industry. Silkworm larvae show typically precocious wandering behavior after being parasitized by E. sorbillans; however, the underlying molecular mechanism remains unexplored. Herein, we investigated the changes in the levels of 20-hydroxyecdysone (20E) and juvenile hormone (JH) titer, and they both increased in the hemolymph of parasitized silkworms. Furthermore, we verified the expression patterns of related genes, which showed an upregulation of 20E signaling and biosynthesis genes but a significant downregulation of ecdysone oxidase (EO), a 20E inactivation enzyme, in parasitized silkworms. In addition, related genes of the JH signaling were activated in parasitized silkworms, while related genes of the JH degradation pathway were suppressed, resulting in an increase in JH titer. Notably, the precocious wandering behavior of parasitized silkworms was partly recoverable by silencing the transcriptions of BmCYP302A1 or BmCYP307A1 genes. Our findings suggest that the developmental duration of silkworm post parasitism could be shortened by regulation of 20E and JH titers, which may help silkworm to resist the E. sorbillans infestation. These findings provide a basis for deeper insight into the interplay between silkworms and E. sorbillans and may serve as a reference for the development of a novel approach to control silkworm myiasis.

Calming the storm: Immunoregulatory receptor NLRX1 and its role in the immune response to SARS-CoV-2

Abstract One of the most characteristic clinical disease presentations of severe COVID-19 is the ‘Cytokine Storm,’ stemming from dysregulation of the immune response. This overproduction of proinflammatory cytokines in response to SARS-CoV-2 is responsible for Acute Respiratory Distress Syndrome (ARDS) in adult patients and the Multisystem Inflammatory Syndrome (MIS) of pediatric patients hospitalized with severe COVID-19. Pattern recognition receptor NLRX1 is a member of the NOD-like receptor family with complex involvement in antiviral immunity. It has been reported in the literature in many contexts to be anti-inflammatory by inhibiting NF-kB and interferon signaling-critical pathways in anti-SARS-CoV-2 immunity. Here we show that loss of NLRX1 impacts immune responses to SARS-CoV-2 both in cell culture and in mice. While Nlrx1 −/−mice showed similar overall morbidity, there were temporary increases in weight loss at multiple time points post infection. SARS-CoV-2 infection of Nlrx1 −/−mice also resulted in an increase in viral titer in the lungs at 2 dpi, despite having higher degrees of airway inflammation. Data in both cell culture and animal challenges report differences in immune activation, showing differences in cytokine production with changes in expression of NLRX1. Together, these experiments uncover another enigmatic function of NLRX1 while simultaneously offering pathways related to NLRX1 as possible therapeutic targets to help mitigate the effects of the ‘cytokine storm’ of severe COVID-19. Finally, these data also add to the growing field regarding SARS-CoV-2 and its pathobiology in an understudied context of immune regulation and continue to explore NLRX1 and its many curious roles in antiviral immunity.

Optimization of Fermentation Conditions for Elevating Limonene Production with Engineered Rhodosporidium toruloides

Limonene is a valuable monoterpenoid with diverse applications in food, medicine, agriculture, etc. Currently, the commercial production of limonene from citrus pomace cannot meet the evergrowing market demand. With the development of synthetic biology, microbial biosynthesis is offering a sustainable alternative to plant-based extraction. However, the performance of engineered strains can be affected by many factors including the microbial host, the cultivation conditions, etc. Therefore, in the present study, potential factors that influence the limonene production of the engineered strains were investigated through single-factor and orthogonal experiments. The optimized medium was MM, with a working volume of 50 mL, inoculum OD600 = 0.6, 22 °C, pH 6, and a dodecane coverage (v/v) of 20%. The final limonene titer was improved from 52.5 to 358.1 mg/L, a 586% net increase in titer and 34.8-fold improvement in production efficiency (mg/OD600) on 250-mL flasks. The results here demonstrated that R. toruloides could be explored as an efficient limonene producer and could facilitate the study of the biosynthesis of other terpenes using R. toruloides.

Impact of perioperative direct oral anticoagulant assays: a multicenter cohort study

ABSTRACT Background There is little evidence to guide the perioperative management of patients on a direct oral anticoagulant (DOAC) in the absence of a last known dose. Quantitative serum titers may be ordered, but there is little evidence supporting this. Aims This multi-center retrospective cohort study of consecutive surgical in-patients with a DOAC assay, performed over a five-year period, aimed to characterize preoperative DOAC assay orders and their impact on perioperative outcomes. Materials and methods Patients prescribed regular DOAC (both prophylactic and therapeutic dosing) with a preoperative DOAC assay were included. The DOAC assay titer was evaluated against endpoints. Further, patients with an assay were compared against anticoagulated patients who did not receive a preoperative DOAC assay. The primary endpoint was major bleeding. Secondary endpoints included perioperative hemoglobin change, blood transfusions, idarucizumab or prothrombin complex concentrate administration, postoperative thrombosis, in-hospital mortality and reoperation. Adjusted and unadjusted linear regression models were used for continuous data. Binary logistic models were performed for dichotomous outcomes Results 1065 patients were included, 232 had preoperative assays. Assays were ordered most commonly by Spinal (11.9%), Orthopedics (15.4%), and Neurosurgery (19.4%). For every 10 ng/ml increase in titer, the hemoglobin decreases by 0.5066 g/L and the odds of a preoperative reversal increases by 13%. Compared to those without an assay, patients with preoperative DOAC assays had odds 1.44× higher for major bleeding, 2.98× higher for in-hospital mortality and 16.3× higher for receiving anticoagulant reversal. Conclusion A preoperative DOAC assay order was associated with worse outcomes despite increased reversal administration. However, the DOAC assay titer can reflect the patient’s likelihood of bleeding.

Metabolomic analysis of the effect glutamate on fengycin-overproducing Bacillus subtilis ATCC 21332 with an enhanced fatty acid synthesis pathway

Fengycin is a of cyclic lipopeptide with antifungal, antitumor and adhesion-preventing activities, with great application potential in biological control, medicine and industry. However, the fermentation yield of fengycin is inadequate, which limits its wider application. In this study, key modules for enhanced fatty acid synthesis were cloned singly and in combination, and the suitability of these modules for B. subtilis ATCC 21332 was investigated. We constructed the engineered strain BSA034, which exhibited a 3-fold increase of fengycin titer, which reached 442.51 mg/L. Reverse transcription and quantitative PCR (RT-qPCR) revealed the effect of enhanced branched-chain fatty acid synthesis on the expression level of the fen operon in B. subtilis ATCC 21332, which significantly contributed to the increase of fengycin production. The exogenous supplementation of glutamate further increased the fengycin titer of BSA034 to 657.55 mg/L. Further comparative metabolomic analysis revealed that glutamate mainly promoted the membrane transport of BSA034, which provides a rational basis for further improving the titer of fengycin in the future.

Immune Response to Seasonal Influenza Vaccination in Multiple Sclerosis Patients Receiving Cladribine.

Cladribine has been approved for the treatment of multiple sclerosis (MS) and its administration results in a long-lasting depletion of lymphocytes. As lymphopenia is known to hamper immune responses to vaccination, we evaluated the immunogenicity of the influenza vaccine in patients undergoing cladribine treatment at different stages vs. controls. The antibody response in 90 cladribine-treated MS patients was prospectively compared with 10 control subjects receiving platform immunotherapy (NCT05019248). Serum samples were collected before and six months after vaccination. Response to vaccination was determined by the hemagglutination-inhibition test. Postvaccination seroprotection rates against influenza A were comparable in cladribine-treated patients and controls (H1N1: 94.4% vs. 100%; H3N2: 92.2% vs. 90.0%). Influenza B response was lower in the cladribine cohort (61.1% vs. 80%). The increase in geometric mean titers was lower in the cladribine group vs. controls (H1N1: +98.5 vs. +188.1; H3N2: +225.3 vs. +300.0; influenza B: +40.0 vs. +78.4); however, titers increased in both groups for all strains. Seroprotection was achieved irrespective of vaccination timing and lymphocyte subset counts at the time of vaccination in the cladribine cohort. To conclude, cladribine-treated MS patients can mount an adequate immune response to influenza independently of treatment duration and time interval to the last cladribine administration.

Hexanoic acid improves the production of lipid and oleic acid in Yarrowia lipolytica: The benefit of integrating biorefinery with organic waste management

Microbial oil serves as a sustainable feedstock for producing biodiesel and bio-jet fuels in biorefineries. Sustainable and economical microbial oil production requires the combination of the biorefinery concept and organic waste management. Here, volatile fatty acids (VFAs), by-products of anaerobic digestion of organic waste, have been incorporated as co-substrates in lignocellulosic microbial oil production by an oleaginous yeast of Yarrowia lipolytica. The supplementation of VFAs (acetic, butyric, and hexanoic acids) increased microbial oil production of Y. lipolytica by up to 47%. Specifically, the oleic acid content in microbial oil increased from 41% to 64% with hexanoic acid supplementation, resulting in a 1.5-fold increase in oleic acid titer. Transcriptome analysis showed that hexanoic acid altered fatty acid metabolism (through β- and ω-oxidation) and global transcriptional regulation during microbial oil production. These findings suggest that hexanoic acid is a useful supplement that improves the industrial yield of microbial oil and selectively increases oleic acid content.

Construct a synthetic Entner–Doudoroff pathway in Bacillus licheniformis for enhancing lichenysin production

Lichenysin, a cyclic lipopeptide biosurfactant produced by Bacillus licheniformis, is composed of aspartate, glutamine, valine, leucine, isoleucine, and branched chain fatty acids. The synthesis of these amino acids and fatty acids requires pyruvate and NADPH as the primary precursor and cofactor. Therefore, a sufficient supply of pyruvate and NADPH is crucial for lichenysin production. This study aimed to increase lichenysin production by constructing a synthetic ED pathway in B. licheniformis WX02 through introducing phosphogluconate dehydratase (encoded by gene edd) and 2-keto-3-deoxygluconate 6-phosphate aldolase (encoded by gene eda) from Escherichia coli. Additionally, the NADP+-dependent glucose-6-phosphate dehydrogenase (encoded by gene zwf) was overexpressed, resulting in an engineered strain WX02/pHY-edda(Ec)-zwf. Analysis of the fermentation process revealed that the concentrations of pyruvate, aspartate, glutamine, valine, leucine, branched-chain fatty acids (iC15:0, aC15:0, iC16:0, iC17:0), and NADPH in WX02/pHY-edda(Ec)-zwf were increased by 77.21%, 80.41%, 85.31%, 141.64%, 44.94%, 35.08%, 38.08%, 19.33%, 21.16%, and 425%, respectively, compared to the control strain WX02/pHY300, which resulted in a 45.43% increase of lichenysin titer. This work took advantage of the ED pathway to increase lichenysin production for the first time, and provides a promising strategy for boosting the productivity of biochemicals that require pyruvate and NADPH as precursor and cofactor.

Generation of polystyrene-specific antibodies for developing immunoassays to analyze microplastics and nanoplastics

Micro- and nano-plastics (MNPs) are emerging pollutants that have drawn worldwide attention due to their negative impacts on the health and sustainability of our ecosystem. Quantitative analysis of MNPs, especially those at nano-scale, is still challenging due to lack of efficient analytical methods. Different antibody-based immunoassay platforms have been well established and readily available for rapid, specific, and quantitative analysis of targets with a broad size range. The key to developing immunoassays for MNP analysis is to generate plastic-specific antibodies, which is still lacking. In this study, we conjugated the nanoparticles of polystyrene (PS), a widely studied representative MNPs, to different carrier proteins for rabbit immunizations. The PS-specific antibodies were significantly induced upon immunization (up to 128-fold increase in IgG titer), which was validated by multi-tier immunoassays using different PS products. Notably, the PS-specific antibodies did not react with polypropylene, a different plastic. Using PS antibody-based enzyme-linked immunoassay, we further demonstrated suitability of the antibody-based immunoassay for quantitative analysis of the PS particles that have been exposed to diverse matrices. Together, this study, for the first time, demonstrates the feasibility of producing plastic-specific antibodies, and lays the groundwork to develop innovative antibody-based immunoassays for future risk assessment and management of MNPs, particularly those at nano-scale.

Adjuvant-Free COVID-19 Vaccine with Glycoprotein Antigen Oxidized by Periodate Rapidly Elicits Potent Immune Responses.

Modification of antigens to improve their immunogenicity represents a promising direction for the development of protein vaccine. Here, we designed facilely prepared adjuvant-free vaccines in which the N-glycan of SARS-CoV-2 receptor-binding domain (RBD) glycoprotein was oxidized by sodium periodate. This strategy only minimally modifies the glycans and does not interfere with the epitope peptides. The RBD glycoprotein oxidized by high concentrations of periodate (RBDHO) significantly enhanced antigen uptake mediated by scavenger receptors and promoted the activation of antigen-presenting cells. Without any external adjuvant, two doses of RBDHO elicited 324- and 27-fold increases in IgG antibody titers and neutralizing antibody titers, respectively, compared to the unmodified RBD antigen. Meanwhile, the RBDHO vaccine could cross-neutralize all of the SARS-CoV-2 variants of concern. In addition, RBDHO effectively enhanced cellular immune responses. This study provides a new insight for the development of adjuvant-free protein vaccines.

Immunogenicity of a new inactivated vaccine against feline panleukopenia virus, calicivirus, and herpesvirus-1 for cats

Feline panleukopenia virus (FPV), feline calicivirus (FCV), and feline herpesvirus type-1 (FHV-1) are major infectious pathogens in cats. We evaluated the immunogenicity of a new vaccine containing inactivated FPV, two FCVs, and FHV-1 in animals. An FPV, two FCVs, and an FHV-1 isolate were continuously passaged 70, 50, 80, and 100 times in CRFK cells. FP70, FC50, FC80, and FH100 were propagated and used as vaccine antigens. Two inactivated feline virus vaccines, Rehydragel-adjuvanted vaccine (FRAV) and Cabopol-adjuvanted vaccine (FCAV) were prepared and inoculated into mice and guinea pigs. Humoral immune responses were measured using hemagglutination inhibition (HI) for FPV and virus-neutralizing antibody (VNA) for two FCVs and FHV-1 tests. Serial passages in CRFK cells resulted in increase in titers of FPV and two FCVs but not FHV-1 The FCAV induced higher mean HI and VNA titers than the FRAV in guinea pigs; therefore, the FCAV was selected. Cats inoculated with FCAV developed a mean HI titer of 259.9 against FPV, and VNA titers of 64, 256, and 3.2 against FCV17D03, FCV17D283, and FHV191071, respectively. Therefore, cats inoculated with the FCAV showed a considerable immune response after receiving a booster vaccination.

Statistical optimization of a podoviral anti-MRSA phage CCASU-L10 generated from an under sampled repository: Chicken rinse.

The insurgence of antimicrobial resistance is an imminent health danger globally. A wide range of challenging diseases are attributed to methicillin-resistant Staphylococcus aureus (MRSA) as it is weaponized with a unique array of virulence factors, and most importantly, the resistance it develops to most of the antibiotics used clinically. On that account, the present study targeted the optimization of the production of a bacteriophage active against MRSA, and evaluating some of its characters. The bacteriophage originated from a quite peculiar environmental source, raw chicken rinse and was suggested to belong to Podoviridae, order Caudovirales. It withstood a variety of extreme conditions and yield optimization was accomplished via the D-optimal design by response surface methodology (RSM). A reduced quadratic model was generated, and the ideal production conditions recommended were pH 8, glycerol 0.9% v/v, peptone 0.08% w/v, and 107 CFU/ml as the host inoculum size. These conditions led to a two-log fold increase in the phage titer (1.17x10¹² PFU/ml), as compared to the regular conditions. To conclude, statistical optimization successfully enhanced the output of the podoviral phage titer by two-log fold and therefore, can be regarded as a potential scale-up strategy. The produced phage was able to tolerate extreme environmental condition making it suitable for topical pharmaceutical preparations. Further preclinical and clinical studies are required to ensure its suitability for use in human.

Antibodies against hyaluronan oligosaccharides in xenotransplantation.

Carbohydrate-specific antibodies are significant mediators of xenograft rejection. This study analyzed the carbohydrate specificity of antibodies in baboons before and after xenotransplantation of organs or injection of porcine red blood cells from hDAF transgenic pigs, using a glycan array with structurally defined glycans. Antibodies against hyaluronic acid disaccharide (HA2) showed the highest reactivity at baseline and rose after xenogeneic exposure. We also investigated in the serum of baboons that underwent xenotransplantation with either hDAF or hDAF/hMCP transgenic pig organs and Lewis rats after hamster-skin xenotransplantation the specificity of anti-HA antibodies on a glycan microarray representing HA oligosaccharides containing from two to 40 saccharides. Notably, the HA oligosaccharides ranging from 32 to 40 saccharides exhibited the highest antibody binding intensities at baseline in baboon and rat sera. After xenotransplantation, antibodies against HA38 and HA40 in baboons, and HA32, HA34, and HA36 in rats showed the highest titer increases. The changes of anti-HA IgM and IgG antibodies in rats after skin xenotransplantation was also confirmed by an ELISA specific for HA2, HA24, and HA85 antibodies. Thus, xenotransplantation is associated with increased antibodies against HA-oligosaccharides, which may represent a new target for intervention.

Metabolic flux enhancement from the translational fusion of terpene synthases is linked to terpene synthase accumulation

The end-to-end fusion of enzymes that catalyse successive steps in a reaction pathway is a metabolic engineering strategy that has been successfully applied in a variety of pathways and is particularly common in terpene bioproduction. Despite its popularity, limited work has been done to interrogate the mechanism of metabolic enhancement from enzyme fusion. We observed a remarkable >110-fold improvement in nerolidol production upon translational fusion of nerolidol synthase (a sesquiterpene synthase) to farnesyl diphosphate synthase. This delivered a titre increase from 29.6 mg/L up to 4.2 g/L nerolidol in a single engineering step. Whole-cell proteomic analysis revealed that nerolidol synthase levels in the fusion strains were greatly elevated compared to the non-fusion control. Similarly, the fusion of nerolidol synthase to non-catalytic domains also produced comparable increases in titre, which coincided with improved enzyme expression. When farnesyl diphosphate synthase was fused to other terpene synthases, we observed more modest improvements in terpene titre (1.9- and 3.8-fold), corresponding with increases of a similar magnitude in terpene synthase levels. Our data demonstrate that increased in vivo enzyme levels – resulting from improved expression and/or improved protein stability – is a major driver of catalytic enhancement from enzyme fusion.

Neutralizing Antibody Response by Inactivated SARS-CoV-2 Vaccine on Healthcare Workers

Background: Currently, the key to combat coronavirus disease 2019 (COVID-19) as a global pandemic is relying mainly on vaccination, and several factors might affect the level of protection. This study aimed to determine the quantitative increase of neutralizing antibody titer against COVID-19 and the influence of gender, body mass index (BMI), routine consumption of vitamin C, D, and E towards the neutralizing antibodies after vaccination.Materials and methods: One hundred nine health workers from various health facilities were recruited. Sinovac inactivated severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine was used in this study. Antibody titer measurements were carried out quantitatively using electrochemiluminescence immunoassay (ECLIA) on day 14 after the first and second doses administration of the vaccine.Results: The average of antibody titers after the first and second doses were 109.1 and 191.6 U/mL, respectively. Antibody titer significantly increased (p=0.000) as much as 82.5 U/mL from the first to the second dose. There was a significant difference in the increase in antibody titer between respondents who consumed vitamin E regularly and those who did not (p=0.036). Routine consumption of vitamin C and D, gender, and BMI did not affect the increase in neutralizing antibody titer with p-values of 0.983, 0.337, 0.186, and 0.424, respectively.Conclusion: Routine consumption of vitamin E is associated with post-SARS-CoV-2 vaccination neutralizing antibody response. Gender, BMI, and the routine consumption of vitamin C and D have no association with the immune response.Keywords: COVID-19, neutralizing antibody, inactivated SARS-CoV-2 vaccine

Possible autoimmune mechanisms of regulation of rat behavior in the “open field” test

BACKGROUND: In recent years, researchers have demonstrated interest in the autoimmune mechanisms of regulation of physiological processes. In response to damage or protein expression, the levels of autoantibodies increased to ensure the restoration of the disturbed balance. Levels of autoantibodies are high in many diseases.
 AIM: The aim of this study was to assess the levels of autoantibodies in the blood serum of experimental animals and evaluate their behavior in the open field test.
 MATERIALS AND METHODS: Of 32 male rats, two groups were formed: group 1 was not exposed to stress, whereas group 2 was subjected to stress for 7 days by applying a clamp on the skin fold for 15 min daily. Three days after the last stress procedure, testing was conducted in the open field. After assessing the behavior, blood serum was obtained, and the levels of autoantibodies to dopamine receptors (DR1 and DR2) and NMDA receptors (NR1, NR2A, and NR2B) were determined.
 RESULTS: Compared with group 1, group 2 visited the central zones of the field less often, had lower vertical activity, and less often performed acts of washing. In group 2, the levels of autoantibodies to DR1 and DR2 were higher, but to NR2B were lower. Correlation analysis revealed that in group 2, the level of autoantibodies to DR2 was associated with horizontal activity (r = 0.60). In group 1, a relationship was established between the level of autoantibodies to NR2B and the number of runs through the central zones of the field (r = +0.68).
 CONCLUSIONS: Taking into account the revealed relationship between the levels of autoantibodies and activity in the open field, the degree of increase in blood IgG titers to DR2 receptors may reflect the severity of changes in the behaviors of animals under stress. Conversely, in connection with the emerging data on the possibility of IgG penetration through the bloodbrain barrier, the effect of autoantibodies on brain dopamine receptors with a limited activity of the dopaminergic system may be considered.

Antinuclear antibody (ANA) status predicts immune-related adverse events in liver cancer patients undergoing anti-PD-1 therapy.

Immune-related adverse events (irAEs) clinically resemble autoimmune diseases, indicating autoantibodies could be potential biomarkers for the prediction of irAEs. This study aimed to assess the predictive value of peripheral blood antinuclear antibody (ANA) status for irAEs, considering the time and severity of irAEs, as well as treatment outcome in liver cancer patients administered anti-PD-1 therapy. Ninety-three patients with advanced primary liver cancer administered anti-PD-1 treatment were analyzed retrospectively. They were divided into the ANA positive (ANA+, titer ≥ 1:100) and negative (ANA-, titer < 1:100) groups. Development of irAEs, progression-free survival (PFS), and overall survival (OS) were assessed. Compared with ANA- patients, ANA+ cases were more prone to develop irAEs (43.3% vs. 19.2%, P = 0.031). With the increase of ANA titers, the frequency of irAEs increased. The time interval between anti-PD-1 therapy and the onset of irAEs was significantly shorter in ANA+ patients compared with the ANA- group (median, 1.7 months vs. 5.0 months, P = 0.022). Moreover, the time between anti-PD-1 therapy and irAE occurrence decreased with increasing ANA titer. In addition, PFS and OS were decreased in ANA+ patients compared with the ANA- group (median PFS, 2.8 months vs. 4.2 months, P = 0.043; median OS, 21.1 months vs. not reached, P = 0.041). IrAEs occur at higher frequency in ANA+ liver cancer patients undergoing anti-PD-1 therapy. ANA titer could help predict irAE development and treatment outcome in these patients.

Effects of Dietary Supplementation of Vitamin E on Growth Performance and Immune System of Broiler Chickens

As a potent antioxidant, Vitamin E may lessen the potentially harmful consequences of such oxidative stress to protect broilers against immune-pathological damage. Broiler chicken growth and viability are enhanced by Vitamin E supplementation. The present study aimed to investigate the effects of Vitamin E dietary supplementation on broiler chickens’ growth performance and health status. A total of 48 one-day-old Ross chicks were randomly divided into two groups of control and treatment (supplementation of Vitamin E at a dose of 300 mg/kg diet) with three replicates per group. The study included an equal number of Ross breed chicks and Vitamin E dosage in two trials on two different dates (January and March, 2022). In both trials, the obtained results indicated no significant changes in weight gain in the control and treatment groups. In both trials, there were no significant differences in the spleen weight of the control and treated groups; however, from day 1 to 28 of the second trial, the bursa of Fabricius was heavier in the treated group than in the control group. Additionally, Vitamin E had no significant effects on the mitogenic responses to phytohemagglutinin (PHA) and Concanavalin A (Con A). Dosages of 20 and 10 µl for both PHA and Con A did not significantly affect the rate of pure lymphocyte proliferation in chicks fed 300 mg Vitamin E /kg feed. Cell-mediated immunity did not differ significantly between the two trials. The percentages of CD4, CD8, Bu1, and MHCII molecules in the spleen and cecal tonsil of the chicks that received Vitamin E 300 mg/kg feed did not change significantly. The antibody titers against infectious bronchitis and infectious bursal disease vaccines showed no significant differences. On day 42, there was a trend toward an increase in antibody titer in the case of the Newcastle disease vaccine. In conclusion, 300 mg/kg of Vitamin E added to the diet did not improve growth performance and immunity in broiler chicks. Keywords: Broiler chicken, Growth performance, Immune system, Vitamin E

Synergistic Detrimental Effects of Cigarette Smoke, Alcohol, and SARS-CoV-2 in COPD Bronchial Epithelial Cells.

Lung conditions such as COPD, as well as risk factors such as alcohol misuse and cigarette smoking, can exacerbate COVID-19 disease severity. Synergistically, these risk factors can have a significant impact on immunity against pathogens. Here, we studied the effect of a short exposure to alcohol and/or cigarette smoke extract (CSE) in vitro on acute SARS-CoV-2 infection of ciliated human bronchial epithelial cells (HBECs) collected from healthy and COPD donors. We observed an increase in viral titer in CSE- or alcohol-treated COPD HBECs compared to untreated COPD HBECs. Furthermore, we treated healthy HBECs accompanied by enhanced lactate dehydrogenase activity, indicating exacerbated injury. Finally, IL-8 secretion was elevated due to the synergistic damage mediated by alcohol, CSE, and SARS-CoV-2 in COPD HBECs. Together, our data suggest that, with pre-existing COPD, short exposure to alcohol or CSE is sufficient to exacerbate SARS-CoV-2 infection and associated injury, impairing lung defences.