Immunosecurity: Strengthen the Impact of Immune Regulation in Domestic Animals

Plenary Sessio

Strengthening the Impact of Immune Regulation in Domestic Animals

Symposium mini revie

A Probiotic Mixture Regulates T Cell Balance and Reduces Atopic Dermatitis Symptoms in Mice

Atopic dermatitis (AD) is a chronic inflammatory skin disorder with a complex etiology involving the immune response. Recent studies have demonstrated the role of certain probiotics in the treatment and prevention of AD. However, the mechanism by which these probiotics regulate the immune system remains unclear. In this study, we examined the immunomodulatory capacity of Duolac ATP, a mixed formulation of probiotics, both in vitro and in vivo. Results showed that the expression of programmed death-ligand 1(PD-L1) was significantly upregulated on bone marrow-derived dendritic cells (BMDCs) treated with Duolac ATP. Furthermore, the anti-inflammatory cytokines IL-10 and TGF-beta were both upregulated when BMDCs were treated with Duolac ATP. The percentage of proliferated regulatory T cells (Tregs) was enhanced when CD4+ T cells were co-cultured with Duolac ATP-treated BMDCs on plates coated with anti-CD3/CD28 antibodies. Intriguingly, IL-10 secretion from CD4+ T cells was also observed. The AD symptoms, histologic scores, and serum IgE levels in AD mice were significantly decreased after oral treatment with Duolac ATP. Moreover, the Th1-mediated response in AD-induced mice treated with oral Duolac ATP showed upregulation of IL-2 and IFN-gamma as well as of downstream signaling molecules T-bet, STAT-1, and STAT-4. Conversely, Duolac ATP suppressed Th2 and Th17 responses in AD-like mice, as evidenced by the downregulation of GATA-3, C-maf, IL-4, IL-5, and IL-17. Additionally, Duolac ATP increased the number of Tregs found at Peyer’s patches (PP) in treated AD mice. These results suggest that Duolac ATP modulates DCs to initiate both Th1 and Treg responses in AD mice. Thus, Duolac ATP represents a potential preventative agent against AD and could serve as an effective immunomodulator in AD patients

Alveolar Macrophages Treated With Bacillus subtilis Spore Protect Mice Infected With Respiratory Syncytial Virus A2

Respiratory syncytial virus (RSV) is a major pathogen that infects lower respiratory tract and causes a common respiratory disease. Despite serious pathological consequences with this virus, effective treatments for controlling RSV infection remain unsolved, along with poor innate immune responses induced at the initial stage of RSV infection. Such a poor innate defense mechanism against RSV leads us to study the role of alveolar macrophage (AM) that is one of the primary innate immune cell types in the respiratory tract and may contribute to protective responses against RSV infection. As an effective strategy for enhancing anti-viral function of AM, this study suggests the intranasal administration of Bacillus subtilis spore which induces expansion of AM in the lung with activation and enhanced production of inflammatory cytokines along with several genes associated with M1 macrophage differentiation. Such effect by spore on AM was largely dependent on TLR-MyD88 signaling and, most importantly, resulted in a profound reduction of viral titers and pathological lung injury upon RSV infection. Taken together, our results suggest a protective role of AM in RSV infection and its functional modulation by B. subtilis spore, which may be a useful and potential therapeutic approach against RSV

Comparative effectiveness of explainable machine learning approaches for extrauterine growth restriction classification in preterm infants using longitudinal data

IntroductionPreterm birth is a leading cause of infant mortality and morbidity. Despite the improvement in the overall mortality in premature infants, the intact survival of these infants remains a significant challenge. Screening the physical growth of infants is fundamental to potentially reducing the escalation of this disorder. Recently, machine learning models have been used to predict the growth restrictions of infants; however, they frequently rely on conventional risk factors and cross-sectional data and do not leverage the longitudinal database associated with medical data from laboratory tests.MethodsThis study aimed to present an automated interpretable ML-based approach for the prediction and classification of short-term growth outcomes in preterm infants. We prepared four datasets based on weight and length including weight baseline, length baseline, weight follow-up, and length follow-up. The CHA Bundang Medical Center Neonatal Intensive Care Unit dataset was classified using two well-known supervised machine learning algorithms, namely support vector machine (SVM) and logistic regression (LR). A five-fold cross-validation, and several performance measures, including accuracy, precision, recall and F1-score were used to compare classifier performances. We further illustrated the models’ trustworthiness using calibration and cumulative curves. The visualized global interpretations using Shapley additive explanation (SHAP) is provided for analyzing variables’ contribution to final prediction.ResultsBased on the experimental results with area under the curve, the discrimination ability of the SVM algorithm was found to better than that of the LR model on three of the four datasets with 81%, 76% and 72% in weight follow-up, length baseline and length follow-up dataset respectively. The LR classifier achieved a better ROC score only on the weight baseline dataset with 83%. The global interpretability results revealed that pregnancy-induced hypertension, gestational age, twin birth, birth weight, antenatal corticosteroid use, premature rupture of membranes, sex, and birth length were consistently ranked as important variables in both the baseline and follow-up datasets.DiscussionThe application of machine learning models to the early detection and automated classification of short-term growth outcomes in preterm infants achieved high accuracy and may provide an efficient framework for clinical decision systems enabling more effective monitoring and facilitating timely intervention

Protects Porcine Intestinal Barrier from Deoxynivalenol via Improved Zonula Occludens-1 Expression

Intestinal epithelial cells (IECs) forming the barrier for the first-line of protection are interconnected by tight junction (TJ) proteins. TJ alteration results in impaired barrier function, which causes potentially excessive inflammation leading to intestinal disorders. It has been suggested that toll-like receptor (TLR) 2 ligands and some bacteria enhance epithelial barrier function in humans and mice. However, no such study has yet to be claimed in swine. The aim of the present study was to examine whether Bacillus subtilis could improve barrier integrity and protection against deoxynivalenol (DON)-induced barrier disruption in porcine intestinal epithelial cell line (IPEC-J2). We found that B. subtilis decreased permeability of TJ and improved the expression of zonula occludens (ZO)-1 and occludin during the process of forming TJ. In addition, ZO-1 expression of IPEC-J2 cells treated with B. subtilis was up-regulated against DON-induced damage. In conclusion, B. subtilis may have potential to enhance epithelial barrier function and to prevent the cells from DON-induced barrier dysfunction

Barrier protection via Toll-like receptor 2 signaling in porcine intestinal epithelial cells damaged by deoxynivalnol

Additional file 2. IPEC-J2 cells pretreated with TLR2 ligand maintained the expression of MCP-1, GM-CSF and TLR2 against DON exposure. IPEC-J2 cells pretreated with or without TLR2 ligand for 24 h were exposed to DON. (A) The bar graph showed the mRNA levels of porcine mcp-1, gm-csf measured using real time-PCR at 1 and 6 h after DON exposure (n = 3). (B) The mRNA levels of porcine tlr2 were measured using real-time quantitative PCR analysis at 6 h. NT represents no treatment. Expression of each mRNA was presented relative to the expression of housekeeping gene, gapdh (n = 3). *P < 0.05; **P < 0.01; ***P < 0.001, determined by one-way ANOVA with Tukey’s posttest

Characterization of splenic MRC1hiMHCIIlo and MRC1loMHCIIhi cells from the monocyte/macrophage lineage of White Leghorn chickens

Monocytes/macrophages, which are found in a variety of organs, maintain tissue homeostasis at a steady state and act as the first line of defence during pathogen-induced inflammation in the host. Most monocyte/macrophage lineage studies in chickens have been largely performed using cell lines, while few studies using primary cells have been conducted. In the present study, the phenotypic and functional characteristics of splenic monocyte/macrophage lineage cells during steady state and inflammatory conditions were examined. Splenic monocyte/macrophage lineage cells could be identified as MRC1loMHCIIhi and MRC1hiMHCIIlo cells based on their surface expression of MRC1 and MHCII. In the steady state, MRC1loMHCIIhi cells were more frequently found among MRC1+ cells. MRC1loMHCIIhi cells expressed a higher number of antigen-presenting molecules (MHCII, MHCI, and CD80) than MRC1hiMHCIIlo cells. In contrast, MRC1hiMHCIIlo cells showed better phagocytic and CCR5-dependent migratory properties than MRC1loMHCIIhi cells. Furthermore, MRC1hiMHCIIlo cells infiltrated the spleen in vivo and then became MRC1loMHCIIhi cells. During lipopolysaccharide (LPS)-induced inflammatory conditions that were produced via intraperitoneal (i.p.) injection, the proportion and absolute number of MRC1hiMHCIIlo cells were increased in the spleen. Uniquely, inflammation induced the downregulation of MHCII expression in MRC1hiMHCIIlo cells. The major source of inflammatory cytokines (IL-1β, IL-6, and IL-12) was MRC1loMHCIIhi cells. Furthermore, MRC1hiMHCIIlo cells showed greater bactericidal activity than MRC1loMHCIIhi cells during LPS-induced inflammation. Collectively, these results suggest that two subsets of monocyte/macrophage lineage cells exist in the chicken spleen that have functional differences.This research was performed with funding from the National Research Foun‑dation (NRF-2018R1A2B2006793), Republic of Korea. This research was also supported by the Cooperative Research Programme for Agriculture Science and Technology Development (Project No. PJ01336401), Rural Development Administration, Republic of Korea. KSY, MJG and YJP were supported by the BK21 Plus Programme of the Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea

Resistin enhances the expansion of regulatory T cells through modulation of dendritic cells

<p>Abstract</p> <p>Background</p> <p>Resistin, a member of adipokine family, is known to be involved in the modulation of immune responses including inflammatory activity. Interestingly, resistin is secreted by adipocytes in mice and rats whereas it is secreted by leukocytes in humans. However, the mechanism behind the effect of resistin on the expansion of regulatory T cells (Tregs) remains poorly understood. Therefore, we examined regulatory effect of resistin on the induction and cellular modification of Tregs.</p> <p>Results</p> <p>Both protein and mRNA expression of <it>FoxP3</it>, a representative marker of Tregs, increased in a dose-dependent manner when peripheral blood mononuclear cells were treated with resistin. At the same time, resistin had no direct effect on the induction of <it>FoxP3 </it>in CD4⁺T cells, suggesting an indirect role through other cells type(s). Since DCs are an important player in the differentiation of T cells, we focused on the role of DCs in the modulation of Tregs by resistin. Resistin suppressed the expression of interferon regulatory factor (IRF)-1 and its target cytokines, IL-6, IL-23p19 and IL-12p40, in DCs. Furthermore, <it>FoxP3 </it>expression is increased in CD4⁺T cells when co-cultured with DCs and concomitantly treated with resistin.</p> <p>Conclusion</p> <p>Our results suggest that resistin induces expansion of functional Tregs only when co-cultured with DCs.</p