Castration alters the ileum microbiota of Holstein bulls and promotes beef flavor compounds.

BACKGROUND: In the beef industry, bull calves are usually castrated to improve flavor and meat quality; however, this can reduce their growth and slaughter performance. The gut microbiota is known to exert a significant influence on growth and slaughter performance. However, there is a paucity of research investigating the impact of castration on gut microbiota composition and its subsequent effects on slaughter performance and meat flavor. RESULT: The objective of this study was to examine the processes via which castration hinders slaughter productivity and enhances meat quality. Bull and castrated calves were maintained under the same management conditions, and at slaughter, meat quality was assessed, and ileum and epithelial tissue samples were obtained. The research employed metagenomic sequencing and non-targeted metabolomics techniques to investigate the makeup of the microbiota and identify differential metabolites. The findings of this study revealed the Carcass weight and eye muscle area /carcass weight in the bull group were significantly higher than those in the steer group. There were no significant differences in the length, width, and crypt depth of the ileum villi between the two groups. A total of 53 flavor compounds were identified in the two groups of beef, of which 16 were significantly higher in the steer group than in the bull group, and 5 were significantly higher in the bull group than in the steer group. In addition, bacteria, Eukaryota, and virus species were significantly separated between the two groups. The lipid metabolism pathways of α-linolenic acid, linoleic acid, and unsaturated fatty acids were significantly enriched in the Steers group. Compared with the steer group, the organic system pathway is significantly enriched in the bull group. The study also found that five metabolites (LPC (0:0/20:3), LPC (20:3/0:0), LPE (0:0/22:5), LPE (22:5/0:0), D-Mannosamine), and three species (s_Cloning_vector_Hsp70_LexA-HP1, s_Bacteroides_Coprophilus_CAG: 333, and s_Clostridium_nexile-CAG: 348) interfere with each other and collectively have a positive impact on the flavor compounds of beef. CONCLUSIONS: These findings provide a basic understanding that under the same management conditions, castration does indeed reduce the slaughter performance of bulls and improve the flavor of beef. Microorganisms and metabolites contribute to these changes through interactions.

Moniezia benedeni drives the SNAP-25 expression of the enteric nerves in sheep's small intestine.

BACKGROUND: The neuroimmune network plays a crucial role in regulating mucosal immune homeostasis within the digestive tract. Synaptosome-associated protein 25 (SNAP-25) is a presynaptic membrane-binding protein that activates ILC2s, initiating the host's anti-parasitic immune response. METHODS: To investigate the effect of Moniezia benedeni (M. benedeni) infection on the distribution of SNAP-25 in the sheep's small intestine, the recombinant plasmid pET-28a-SNAP-25 was constructed and expressed in BL21, yielding the recombinant protein. Then, the rabbit anti-sheep SNAP-25 polyclonal antibody was prepared and immunofluorescence staining was performed with it. The expression levels of SNAP-25 in the intestines of normal and M. benedeni-infected sheep were detected by ELISA. RESULTS: The results showed that the SNAP-25 recombinant protein was 29.3 KDa, the titer of the prepared immune serum reached 1:128,000. It was demonstrated that the rabbit anti-sheep SNAP-25 polyclonal antibody could bind to the natural protein of sheep SNAP-25 specifically. The expression levels of SNAP-25 in the sheep's small intestine revealed its primary presence in the muscular layer and lamina propria, particularly around nerve fibers surrounding the intestinal glands. Average expression levels in the duodenum, jejunum, and ileum were 130.32 pg/mg, 185.71 pg/mg, and 172.68 pg/mg, respectively. Under conditions of M. benedeni infection, the spatial distribution of SNAP-25-expressing nerve fibers remained consistent, but its expression level in each intestine segment was increased significantly (P < 0.05), up to 262.02 pg/mg, 276.84 pg/mg, and 326.65 pg/mg in the duodenum, jejunum, and ileum, and it was increased by 101.06%, 49.07%, and 89.16% respectively. CONCLUSIONS: These findings suggest that M. benedeni could induce the SNAP-25 expression levels in sheep's intestinal nerves significantly. The results lay a foundation for further exploration of the molecular mechanism by which the gastrointestinal nerve-mucosal immune network perceives parasites in sheep.

Similar proteome expression profiles of the aggregated lymphoid nodules area and Peyer's patches in Bactrian camel.

BACKGROUND: The presence of Aggregated Lymphoid Nodules Area (ALNA) is a notable anatomical characteristic observed in the abomasum of Bactrian camels. This area is comprised of two separate regions, namely the Reticular Mucosal Folds Region (RMFR) and the Longitudinal Mucosal Folds Region (LMFR). The histological properties of ALNA exhibit significant similarities to those of Peyer's patches (PPs) found in the gastrointestinal system. The functional characteristics of ALNA were examined in relation to mucosal immunity in the gastrointestinal system. RESULTS: We used iTRAQ-based proteomic analysis on twelve Bactrian camels to measure the amount of proteins expressed in ALNA. In the experiment, we sampled the RMFR and LMFR separately from the ALNA and compared their proteomic quantification results with samples from the PPs. A total of 1253 proteins were identified, among which 39 differentially expressed proteins (DEPs) were found between RMFR and PPs, 33 DEPs were found between LMFR and PPs, and 22 DEPs were found between LMFR and RMFR. The proteins FLNA, MYH11, and HSPB1 were chosen for validation using the enzyme-linked immunosorbent assay (ELISA), and the observed expression profiles were found to be in agreement with the results obtained from the iTRAQ study. The InnateDB database was utilized to get data pertaining to immune-associated proteins in ALNA. It was observed that a significant proportion, specifically 76.6%, of these proteins were found to be associated with the same orthogroups as human immune-related genes. These proteins are acknowledged to be associated with a diverse range of functions, encompassing the uptake, processing and presentation of antigens, activation of lymphocytes, the signaling pathways of T-cell and B-cell receptors, and the control of actin polymerization. CONCLUSIONS: The experimental results suggest that there are parallels in the immune-related proteins found in ALNA and PPs. Although there are variations in the structures of LMFR and RMFR, the proteins produced in both structures exhibit a high degree of similarity and perform comparable functions in the context of mucosal immune responses.

Yujin powder improves large intestine dampness-heat syndrome by regulating gut microbiota and serum metabolism.

Large intestine dampness-heat syndrome (LIDHS) is a common syndrome type in animal diarrheal diseases. Yujin powder (YJP) is one of the classic prescriptions for treating damp-heat diarrhea. The aim of this study was to investigate the regulatory effects of YJP on gut microbiota and serum metabolism in LIDHS rats using 16S rRNA sequencing and nontargeted metabolomics. The LIDHS rat model was induced through a high-sugar and high-fat diet, exposure to a high-temperature and high-humidity environment, and infection with Escherichia coli. The results demonstrated that the administration of YJP resulted in a decrease in the abundance of Desulfovibrio, Parabacteroides, Bacteroides, Allobaculum, Escherichia, Butyricimonas, Parasutterella, and Blautia and an increase in Ruminococcus, Akkermansia, Roseburia, and Lachnoclostridium. A total of 25 potential biomarkers were identified in three groups of rats. These metabolites were primarily involved in glycerophospholipid metabolism, taurine and hypotaurine metabolism, glycerol ester metabolism, arachidonic acid metabolism, primary bile acid synthesis, and tryptophan metabolism. Our study demonstrated that YJP has the potential to alleviate LIDHS by modulating gut microbial and serum metabolic homeostasis. These results establish a foundation and offer valuable guidance for the utilization of YJP in the treatment of LIDHS.

Establishment of Bactrian Camel Induced Pluripotent Stem Cells and Prediction of Their Unique Pluripotency Genes.

Induced pluripotent stem cells (iPSCs) can differentiate into all types of cells and can be used in livestock for research on biological development, genetic breeding, and in vitro genetic resource conservation. The Bactrian camel is a large domestic animal that inhabits extreme environments and holds value in the treatment of various diseases and the development of the local economy. Therefore, we transferred four mouse genes (Oct4, Sox2, Klf4, and c-Myc) into Bactrian camel fetal fibroblasts (BCFFs) using retroviruses with a large host range to obtain Bactrian camel induced pluripotent stem cells (bciPSCs). They were comprehensively identified based on cell morphology, pluripotency gene and marker expression, chromosome number, transcriptome sequencing, and differentiation potential. The results showed the pluripotency of bciPSCs. However, unlike stem cells of other species, late formation of stem cell clones was observed; moreover, the immunofluorescence of SSEA1, SSEA3, and SSEA4 were positive, and teratoma formation took four months. These findings may be related to the extremely long gestation period and species specificity of Bactrian camels. By mining RNA sequence data, 85 potential unique pluripotent genes of Bactrian camels were predicted, which could be used as candidate genes for the production of bciPSC in the future. Among them, ASF1B, DTL, CDCA5, PROM1, CYTL1, NUP210, Epha3, and SYT13 are more attractive. In conclusion, we generated bciPSCs for the first time and obtained their transcriptome information, expanding the iPSC genetic information database and exploring the applicability of iPSCs in livestock. Our results can provide an experimental basis for Bactrian camel ESC establishment, developmental research, and genetic resource conservation.

Optimization of Ethanol Extraction Technology for Yujin Powder Using Response Surface Methodology with a Box-Behnken Design Based on Analytic Hierarchy Process-Criteria Importance through Intercriteria Correlation Weight Analysis and Its Safety Evaluation.

Here, we aimed to optimize the ethanol extraction technology for Yujin powder (YJP) and evaluate its safety. The ultrasonic-assisted ethanol reflux extraction method refluxing was used to extract YJP. The parameters were optimized through a combination of single-factor and response surface methodology (RSM). The comprehensive Y value score calculated using the content of 13 active ingredients in YJP ethanolic extracts (YEEs) and the yield of the dry extract were used as measuring criteria. RSM with a Box-Behnken design using three factors and three levels was adopted to optimize the ethanol extraction technology for YJP. Finally, acute and subchronic toxicity tests were performed to evaluate its safety. The results revealed the best technological parameters: a liquid-material ratio of 24:1, an ethanol concentration of 69%, assistance of ultrasound (40 °C, 50 kHZ, 30 min), reflux time of 53 min, and reflux temperature of 50 °C. In acute toxicity tests, the maximum administration dosage in mice was 28.21 g/kg, which is higher than 10 times the clinical dosage. Adverse effects in the acute and subchronic toxicity tests were not observed. All clinical indexes were normal. In conclusion, the RSM based on AHP-CRITIC weight analysis could be used to optimize the ethanol extraction technology for YJP and YEEs prepared under the above conditions and ensure high safety.

Moniezia benedeni infection enhances neuromedin U (NMU) expression in sheep (Ovis aries) small intestine.

BACKGROUND: Neuromedin U (NMU) plays an important role in activating the group 2 innate lymphoid cells (ILC2s) and initiating the host's anti-parasitic immune responses. It is aimed to explore the distribution characteristics of NMU in the sheep small intestine and the influence of Moniezia benedeni infection on them. In the present study, the pET-28a-NMU recombinant plasmids were constructed, and Escherichia coli. BL21 (DE3) were induced to express the recombinant protein. And then, the rabbit anti-sheep NMU polyclonal antibody was prepared and immunofluorescence staining was performed with it. The expression levels of NMU in the intestine of normal and Moniezia benedeni-infected sheep were detected by ELISA. RESULTS: The results showed that the molecular weight of the obtained NMU recombinant protein was consistent with the expected molecular (13 kDa) and it was expressed in the form of inclusion body. The titer and specificity of obtained rabbit anti-sheep NMU polyclonal antibody were good. The results of immunofluorescence analysis showed that the nerve fibers which specifically expressed NMU mainly extended from the ganglion in the submucosal to lamina propria (LP) in the sheep small intestine, and the expression level was relatively high; especially on the nerve fibers of LP around the intestinal glands. The expression levels were gradually increased from the duodenum to the ileum, and the levels in the jejunum and ileum were significantly higher than that in the duodenum (P < 0.05). In addition, scattered NMU positive cells were distributed in the epithelium of the jejunal crypts. Moniezia benedeni infection increased the expression of NMU in each intestinal segment, especially in the jejunum and ileum there were significant increase (P < 0.05). CONCLUSIONS: It was suggested that Moniezia benedeni infection could be detected by the high expression of NMU in sheep enteric nervous, and which laid the foundation for further studies on whether NMU exerts anti-parasitic immunity by activating ILC2s. In addition, NMU was expressed in some intestinal gland epitheliums, which also provided a basis for studying its roles in regulation of the immune homeostasis. The present study laid the foundation for further revealing the molecular mechanism of sheep's neural-immune interaction network perceiving the colacobiosis of parasites.

Comparative transcriptomics and histopathological analysis of crucian carp infection by atypical Aeromonas salmonicida.

Aeromonas salmonicida is a ubiquitous fish pathogen known to cause furunculosis. With the emergence of new subtypes and the expansion of the host range, it has threatened the health of a variety of marine and freshwater fish, particularly the non-salmonids, manifesting differently from the classical furunculosis. Although there have been reports of infection by atypical strains on the crucian carp, the pathogenesis and tissue pathology remain unclear. In this study, transcriptomics and histopathology were used to analyze the immune response and lesions of crucian carp infected with A. salmonicida. Comparative analysis showed 6579 differentially expressed genes (DEGs) (3428 down-regulated and 3151 up-regulated) were identified on day 5 post-infection (5 dpi). Further annotation and analysis revealed that the DEGs were enriched in enzyme regulator activity, response to oxidative stress, iron ion homeostasis and other functions, and mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), toll-like receptor (TLR), and nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) etc., and immune-related signaling pathways. Meanwhile, the four C-type lysozyme genes found in all DEGs were significantly up-regulated after infection. In addition, there was severe bleeding on the body of the infected fish. Also, the intestine, liver, spleen, and kidney showed varying degrees of inflammatory damage, especially the goblet cell hyperplasia of intestinal mucosa epithelium and degeneration and necrosis of renal tubular epithelium cells. Additionally, with the increase in pathogen concentration, the cumulative mortality increased, the severity of lesions in the hindgut and head-kidney tissues increased. The relative expression levels of four immune-related genes (TNF-α, IL-1ß, IL-11, C-lysozyme) were also significantly upregulated, compared with the control (P < 0.05). In conclusion, this study provides a scientific basis for further study on the immune response, pathological diagnosis, and prevention of crucian carp infection caused by atypical A. salmonicida.

Baculoviral infection reduces the expression of four allergen proteins of silkworm pupa.

Silkworm (Bombyx mori) larvae are widely used to express exogenous proteins. Moreover, some silkworm pupal proteins can be used as drug-loading materials for selfexpressed oral tolerance drugs. However, several proteins expressed in silkworm pupae cause severe allergic reactions in humans and animals. Interestingly, some baculovirus vectors have been shown to alter the host gene and its expression in insect cells, but this has not been confirmed in silkworm. Here, we analyzed the effects of infection with an empty B. mori baculovirus (BmNPV) vector on silkworm pupal protein expression. Using a proteomics approach, the allergens thiol peroxiredoxin (Jafrac1), 27-kDa glycoprotein (p27k), arginine kinase, and paramyosin as well as 32 additional differentially expressed proteins were identified. Downregulation of the messenger RNA expression of the four known allergens was observed after BmNPV infection; subsequent changes in protein expression were confirmed by the western blot analysis using polyclonal antibodies prepared with recombinant proteins of the four allergens. Collectively, these data indicate that the four known allergens of silkworm pupae can be reduced by infection ith an empty BmNPV vector to increase the safety of silkworm pupa-based exogenous protein expression and drug delivery of oral pharmaceuticals. In addition, the four recombinant allergen proteins may contribute to the diagnosis of allergic diseases of silkworm pupa.

Localization of neonatal Fc receptor for IgG in aggregated lymphoid nodules area in abomasum of Bactrian camels (Camelus bactrianus) of different ages.

BACKGROUND: The neonatal Fc receptor (FcRn) plays a crucial role in transporting IgG and associated antigens across polarized epithelial barriers in mucosal immunity. However, it was not clear that FcRn expression in aggregated lymphoid nodules area (ALNA) in abomasum, a unique and important mucosal immune structure discovered only in Bactrian camels. In the present study, 27 Alashan Bactrian camels were divided into the following five age groups: fetus (10-13 months of gestation), young (1-2 years), pubertal (3-5 years), middle-aged (6-16 years) and old (17-20 years). The FcRn expressions were observed and analyzed in detail with histology, immunohistochemistry, micro-image analysis and statistical methods. RESULTS: The results showed that the FcRn was expressed in mucosal epithelial cells of ALNA from the fetus to the old group, although the expression level rapidly declined in old group; moreover, after the ALNA maturated, the FcRn expression level in the non-follicle-associated epithelium (non-FAE) was significantly higher than that in FAE (P < 0.05). In addition, the FcRn was also expressed in the vessel endothelium, smooth muscle tissue, and macrophages and dendritic cells (DCs) of secondary lymphoid follicles (sLFs). CONCLUSIONS: It was demonstrated that FcRn was mainly expressed in non-FAE, the effector sites, although which was expressed in FAE, the inductive sites for mucosal immunity. And it was also expressed in DCs and macrophages in sLFs of all ages of Bactrian camels. The results provided a powerful evidence that IgG (including HCAb) could participate in mucosal immune response and tolerance in ALNA of Bactrian camels through FcRn transmembrane transport.

Distribution of immunoglobulin G antibody secretory cells in small intestine of Bactrian camels (Camelus bactrianus).

BACKGROUND: To explore the morphological evidence of immunoglobulin G (IgG) participating in intestinal mucosal immunity, 8 healthy adult Bactrian camels used. First, IgG was successfully isolated from their serum and rabbit antibody against Bactrian camels IgG was prepared. The IgG antibody secretory cells (ASCs) in small intestine were particularly observed through immumohistochemical staining, then after were analyzed by statistical methods. RESULTS: The results showed that the IgG ASCs were scattered in the lamina propria (LP) and some of them aggregated around of the intestinal glands. The IgG ASCs density was the highest from middle segment of duodenum to middle segment of jejunum, and then in ended segment of jejunum and initial segment of ileum, the lowest was in initial segment of duodenum, in middle and ended segment of ileum. CONCLUSIONS: It was demonstrated that the IgG ASCs mainly scattered in the effector sites of the mucosal immunity, though the density of IgG ASCs was different in different segment of small intestine. Moreover, this scatted distribution characteristic would provide a morphology basis for research whether IgG form a full-protection and immune surveillance in mucosal immunity homeostasis of integral intestine.

Moniezia benedeni drives CD3+ T cells residence in the sheep intestinal mucosal effector sites.

Introduction: T cells are the core of the cellular immunity and play a key role in the regulation of intestinal immune homeostasis. In order to explore the impact Moniezia benedeni (M. benedeni) infection on distributions of CD3+ T cells in the small intestine of the sheep. Methods: In this study, sheep pET-28a-CD3 recombinant plasmid were constructed and expressed in BL21 receptor cells, then the rabbit anti-sheep CD3 polyclonal antibody was prepared through recombinant protein inducing. The M. benedeni-infected sheep (infection group, n = 6) and healthy sheep (control group, n = 6) were selected, and the distributions of CD3+ T cells in intestinal laminae propria (LP) and mucous epitheliums were observed and analyzed systematically. Results: The results showed that the rabbit anti-sheep CD3 polyclonal antibody had good potency and specificity. In the effector area of small intestine, a large number of CD3+ T cells were mainly diffusely distributed in the intestinal LP as well as in the mucous epitheliums, and the densities of intestinal LP from duodenum to jejunum to ileum were 6.01 cells/104 µm2, 7.01 cells/104 µm2 and 6.43 cells/104 µm2, respectively. Their distribution densities in mucous epitheliums were 6.71 cells/104 µm2, 7.93 cells/104 µm2 and 7.21 cells/104 µm2, respectively; in the infected group, the distributions of CD3+ T cells were similar to that of the control group, and the densities in each intestinal segment were all significantly increased (p < 0.05), meanwhile, the total densities of CD3+ T cells in duodenum, jejunum and ileum were increased by 33.43%, 14.50%, and 34.19%. In LP and mucous epitheliums, it was increased by 33.57% and 27.92% in duodenum; by 25.82% and 7.07% in jejunum, and by 27.07% and 19.23% in ileum, respectively. Discussion: It was suggested that M. benedeni infection did not change the spatial distributions of CD3+ T cells in the small intestine of sheep, but significantly increased their densities, which lays a foundation for further research on the regulatory mechanism of sheep intestinal mucosal immune system against M. benedeni infection.

Age-dependent distribution of IgA and IgG antibody-secreting cells in the pharyngeal tonsil of the Bactrian camel.

The pharyngeal tonsil, located in the nasopharynx, can effectively defend against pathogens invading the body from the upper respiratory tract and play a crucial role in mucosal immunity of the respiratory tract. Immunoglobulin A (IgA) and Immunoglobulin G (IgG) serve as key effector molecules in mucosal immunity, exhibiting multiple immune functions. This study aimed to investigate the distribution patterns and age-related alterations of IgA and IgG antibody-secreting cells (ASCs) in the pharyngeal tonsils of Bactrian camels. Twelve Alashan Bactrian camels were categorized into four age groups: young (1-2 years, n=3), pubertal (3-5 years, n=3), middle-aged (6-16 years, n=3) and old (17-20 years, n=3). The distribution patterns of IgA and IgG ASCs in the pharyngeal tonsils of Bactrian camels of different ages were meticulously observed, analyzed and compared using immunohistochemical and statistical methods. The results revealed that IgA ASCs in the pharyngeal tonsils of all age groups were primarily clustered or diffusely distributed in the reticular epithelium and its subepithelial regions (region A) and around the glands (region C), scattered in the subepithelial regions of non-reticular epithelium (region B), and sporadically distributed in the interfollicular regions (region D). Interestingly, the distribution pattern of IgG ASCs in the pharyngeal tonsils closely mirrored that of IgA ASCs. The distribution densities of IgA and IgG ASCs in these four regions were significantly decreased in turn (P<0.05). However, IgA ASCs exhibited significantly higher densities than IgG ASCs in the same region (P<0.05). Age-related alterations indicated that the distribution densities of IgA and IgG ASCs in each region of the pharyngeal tonsils exhibited a trend of initially increasing and subsequently decreasing from young to old camels, reaching a peak in the pubertal group. As camels age, there was a significant decrease in the densities of IgA and IgG ASCs in all regions of the pharyngeal tonsils (P<0.05). The results demonstrate that the reticular epithelium and its subepithelial regions in the pharyngeal tonsils of Bactrian camels are the primary regions where IgA and IgG ASCs colonize and exert their immune functions. These regions play a pivotal role in inducing immune responses and defending against pathogen invasions in the pharyngeal tonsils. IgA ASCs may be the principal effector cells of the mucosal immune response in the pharyngeal tonsils of Bactrian camels. Aging significantly reduces the densities of IgA and IgG ASCs, while leaving their distribution patterns unaffected. These findings will provide valuable insights for further investigations into the immunomorphology, immunosenescence, and response mechanisms of the pharyngeal tonsils in Bactrian camels.

Distribution characteristics of gastric mucosal colonizing microorganisms in different glandular regions of Bactrian camels and their relationship with local mucosal immunity.

Bactrian camels inhabiting desert and semi-desert regions of China are valuable animal models for studying adaptation to desert environments and heat stress. In this study, 16S rRNA technology was employed to investigate the distribution characteristics and differences of mucosal microorganisms in the anterior gland area, posterior gland area, third gland area, cardia gland area, gastric fundic gland area and pyloric gland area of 5-peak adult healthy Bactrian camels. We aimed to explore the possible reasons for the observed microbial distribution from the aspects of histological structure and mucosal immunity. Bacteroides and Fibrobacteria accounted for 59.54% and 3.22% in the gland area, respectively, and 52.37% and 1.49% in the wrinkled stomach gland area, respectively. The gland area showed higher abundance of Bacteroides and Fibrobacteria than the wrinkled stomach gland area. Additionally, the anterior gland area, posterior gland area, third gland area, and cardia gland area of Bactrian camels mainly secreted acidic mucus, while the gastric fundic gland area mainly secreted neutral mucus and the pyloric region mainly secreted a mixture of acidic and neutral mucus. The results of immunohistochemistry techniques demonstrated that the number of IgA+ cells in the anterior glandular area, posterior glandular area, third glandular area, and cardia gland area was significantly higher than that in the fundic and pyloric gland area (p < 0.05), and the difference in IgA+ between the fundic and pyloric gland area was not significant (p > 0.05). The study revealed a large number of bacteria that can digest and degrade cellulose on the mucosa of the gastric gland area of Bactrian camels. The distribution of IgA+ cells, the structure of the mucosal tissue in the glandular region, and the composition of the mucus secreted on its surface may have a crucial influence on microbial fixation and differential distribution.

Moniezia benedeni infection increases IgE+ cells in sheep (Ovis aries) small intestine.

The concentration of immunoglobulin (Ig) E is the lowest among serum Igs, but it can induces type I hypersensitivity and plays an important role in anti-parasitic infection. The present study aimed to explore the residence characteristics of IgE+ cells in the sheep small intestine and the impact of Moniezia benedeni infection on them. The recombinant plasmids pET-28a-IgE were constructed and induced and expressed in Escherichia coli. BL21 (DE3). The rabbit anti-sheep IgE polyclonal antibody was prepared using the obtained recombinant protein as antigen. Finally, the levels of IgE+ cells in the small intestine of healthy (Control group) and naturally M. benedeni-infected (Infected group) sheep were detected analyzed. The results showed that the rabbit anti-sheep IgE polyclonal antibody with good immunogenicity (titer = 1: 128000) could specifically bind to the heavy chain of natural sheep IgE. In the Control group, the IgE+ cells were mainly distributed in lamina propria of the small intestine, and the densities were significantly decreased from duodenum to ileum (P<0.05), with respective values of (4.28 cells / 104 µm2, 1.80 cells / 104 µm2, and 1.44 cells / 104 µm2 in duodenum, jejunum, and ileum. In the Infected group, IgE+ cells density were 6.26 cells / 104 µm2, 3.01 cells / 104 µm2, and 2.09 cells / 104 µm2 in duodenum, jejunum and ileum respectively, which were significantly higher in all segments compared to the Control group (P<0.05), increasing by 46.26%, 67.22% and 45.14%, respectively. In addition, compared with the Control group, the IgE protein levels were significantly increased in all intestinal segments of the Infected group (P<0.01), however, there was no significant differences among the different intestinal segments within the same group (P>0.05). The results demonstrated that M. benedeni infection could significantly increase the content of IgE and the distribution density of its secreting cells in sheep small intestine. The intestinal mucosal immune system of sheep presented obvious specificity against M. benedeni infection. This lays a good foundation for further exploring molecular mechanisms of the intestinal mucosal immune system monitoring and responding to M. benedeni infection.

Clinical Value of Detecting Fecal Calprotectin by Using Colloidal Gold Assay in Screening or Diagnosing Crohn's Disease.

Background: Crohn's disease (CD) is a chronic inflammatory disease, and its incidence is gradually increasing. Thus, the use of a simple and convenient examination method to detect CD in the natural population as early as possible is crucial. This study is aimed at using the colloidal gold semiquantitative assay to detect fecal calprotectin (FCP) and determine whether it is helpful in screening or diagnosing CD. Methods: Using a prospectively maintained database, 59 patients with CD were analyzed using FCP measurement. Subsequently, 76 patients and 89 healthy individuals were assigned to the gastrointestinal dysfunction and control groups, respectively. To aid in the screening or diagnosis of CD, the receiver operating characteristic curve was used to determine the diagnostic efficacy of FCP thresholds. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were presented with 95% confidence intervals (CIs). Results: Patients with CD showed significantly higher FCP levels. Compared with the healthy population, when the FCP level cut-off was 15 µg/g and 60 µg/g, the sensitivity, specificity, PPV, and NPV for CD diagnosis were 98.3% (CI, 95.0%-100%) and 78.0% (CI, 67.4-88.6%), 84.3% (CI, 76.7%-91.8%) and 98.9% (CI, 96.7%-100%), 80.6% (CI, 71.5%-89.7%) and 97.9% (CI, 93.7%-100%), and 98.7% (CI, 96.2%-100%) and 87.1% (CI, 80.6%-93.6%), respectively. The AUCs were 0.969 (CI, 0.941-0.997). Compared with the gastrointestinal dysfunction group, using the same FCP level cut-off, the sensitivity, specificity, PPV, and NPV for CD diagnosis were 98.3% (CI, 95.0%-100%) and 78.0% (CI, 67.4%-88.6%), 71.1% (CI, 60.9%-81.3%) and 89.5% (CI, 82.3%-96.7%), 72.5% (CI, 62.7%-82.3%) and 85.2% (CI, 75.7%-94.7%), and 98.1% (CI, 94.5%-100%) and 84.0% (CI, 76.0%-92.0%), respectively. The AUCs were 0.908 (CI, 0.856-0.960). Conclusion: Detecting FCP by using the colloidal gold semiquantitative assay can be effective in screening and adjunct diagnosing of CD.

Preparation of IgE Antibody and Distribution of IgE+ Secretory Cells in the Palatine Tonsil of Bactrian Camel.

BACKGROUND: Allergic diseases induced by dust have seriously threatened human health, while Bactrian camels can live in a sandy environment for a long time. OBJECTIVE: To prepare rabbit anti-Bactrian camel IgE antibody and explore the distribution characteristics of IgE+ secretory cells in the palatine tonsils, which lays a theoretical foundation for the distribution of local antibodies in the palatal tonsils of Bactrian camel and the study of immune function. METHODS: In this study, the amino acid sequences of Bactrian camel IgE, IgA, IgM and IgG heavy chain constant regions were compared, and a specific IgE gene fragment were selected (447 bp). The recombinant plasmid pET-28a-IgE was induced in Escherichia coli BL21(DE3) by IPTG and its expression conditions were optimized. The antibody was prepared by immunizing rabbits with purified IgE recombinant protein, its titer and specificity were detected by indirect ELISA and Western blotting. Immunohistochemical and statistical methods investigated the distribution of IgE+ secretory cells in the palatine tonsils. RESULTS: The IgE recombinant protein was expressed in the form of inclusion bodies with a size of 16 kDa. The optimal IPTG induction concentration was 0.7 mmol/L and the induction time was 8 h. The titer of the antibody was 1:16000 by ELISA, and the antibody could specifically bind to the recombinant protein by Western blotting. IgE+ secretory cells were mainly distributed in the subepithelial compartments of reticulated crypt epithelium of the palatine tonsil of the Bactrian camel, followed by the subepithelial compartments of stratified squamous epithelium and occasionally in the extrafollicular region. CONCLUSION: The rabbit anti-Bactrian camel IgE polyclonal antibody was successfully prepared. It is confirmed that IgE exists in the palatine tonsils of Bactrian camels under normal living conditions. In addition, IgE+ secretory cells are mainly distributed in the subepithelial compartments of reticulated crypt epithelium of the palatine tonsil, which is consistent with the distribution characteristics of IgG+ and sIgA+ secretory cells in the palatal tonsils of the Bactrian camel.

D-BIN: A Generalized Disentangling Batch Instance Normalization for Domain Adaptation.

Pattern recognition is significantly challenging in real-world scenarios by the variability of visual statistics. Therefore, most existing algorithms relying on the independent identically distributed assumption of training and test data suffer from the poor generalization capability of inference on unseen testing datasets. Although numerous studies, including domain discriminator or domain-invariant feature learning, are proposed to alleviate this problem, the data-driven property and lack of interpretation of their principle throw researchers and developers off. Consequently, this dilemma incurs us to rethink the essence of networks' generalization. An observation that visual patterns cannot be discriminative after style transfer inspires us to take careful consideration of the importance of style features and content features. Does the style information related to the domain bias? How to effectively disentangle content and style features across domains? In this article, we first investigate the effect of feature normalization on domain adaptation. Based on it, we propose a novel normalization module to adaptively leverage the propagated information through each channel and batch of features called disentangling batch instance normalization (D-BIN). In this module, we explicitly explore domain-specific and domaininvariant feature disentanglement. We maneuver contrastive learning to encourage images with the same semantics from different domains to have similar content representations while having dissimilar style representations. Furthermore, we construct both self-form and dual-form regularizers for preserving the mutual information (MI) between feature representations of the normalization layer in order to compensate for the loss of discriminative information and effectively match the distributions across domains. D-BIN and the constrained term can be simply plugged into state-of-the-art (SOTA) networks to improve their performance. In the end, experiments, including domain adaptation and generalization, conducted on different datasets have proven their effectiveness.

Localization of FGF21 Protein and Lipid Metabolism-Related Genes in Camels.

With the ability to survive under drought and chronic hunger, camels display a unique regulation characteristic of lipid metabolism. Fibroblast growth factor (FGF) 21 is a peptide hormone that regulates metabolic pathways, especially lipid metabolism, which was considered as a promising therapeutic target for metabolic diseases. To understand the FGF21 expression pattern and its potential relationship with lipid metabolism in camels, this study investigated the distribution and expression of FGF21, receptor FGFR1, and two lipid metabolism markers, leptin and hormone-sensitive lipase (HSL), using an immunohistochemistry (IHC) assay. The results showed that FGF21 was widely expressed in camel central nerve tissue and peripheral organs but absent in lung and gametogenic tissue, including the testis, epididymis, and ovary. In striated muscle, FGF21 is only present at the fiber junction. FGFR1 is expressed in almost all tissues and cells, indicating that all tissues are responsive to FGF21 and other FGF-mediated signals. Leptin and HSL are mainly located in metabolic and energy-consuming organs. In the CNS, leptin and HSL showed a similar expression pattern with FGFR1. In addition, leptin expression is extremely high in the bronchial epithelium, which may be due to its role in the immune responses of respiratory mucosa, in addition to fat stores and energy balance. This study found that FGF21 showed active expression in the nervous system of camels, which may be related to the adaptability of camels to arid environments and the specific regulation of lipid metabolism. This study showed a special FGF21-mediated fat conversion pattern in camels and provides a reference for developing a potential therapeutic method for fat metabolism disease.

Effects of Oregano Essential Oil on IgA+, IgG+, and IgM+ Cells in the Jejunum of Castrated Holstein Bulls.

The aim of this study was to investigate the effect of oregano essential oil on IgA+, IgG+, and IgM+ cells in the jejunum of castrated Holstein bulls. Twelve castrated Holstein bulls were randomly divided into control (YCK) and oregano essential oil (YEO) groups. Pathological changes in the jejunum were observed by HE staining, and the expression levels of IgA, IgG, and IgM in the jejunum were detected by ELISA. The distributions of IgA+, IgG+, and IgM+ cells in the jejunum were analysed by multiplex immunofluorescence and immunohistochemistry. The results showed that the jejunal villi were detached in the YCK group, which may have been related to inflammation, while the intestinal epithelium was clear and intact in the YEO group. The expressions of IgA, IgG, and IgM were significantly reduced by 40.75%, 30.76%, and 50.87%. The IgA+, IgG+, and IgM+ cells were diffusely distributed in the lamina propria of the jejunum, and were reduced by 17.07%, 6.44%, and 6.15%, respectively. Oregano essential oil did not alter the distribution characteristics of IgA+, IgG+, or IgM+ cells in the jejunum, but it suppressed inflammatory response, decreased immunoglobulin content, and significantly enhanced the formation of an immune barrier in the gastrointestinal mucosa.