Constipation occurs frequently in both sows and humans, particularly, during late gestation. The microbial community of the porcine gut, the enteric microbiota, plays a critical role in functions that sustain intestinal health. Hence, microbial regulation during pregnancy may be important to prevent host constipation. The present study was conducted to determine whether L-glutamine (Gln) supplementation improved intestinal function and alleviated constipation by regulation of enteric microbiota. 16S rRNA sequences obtained from fecal samples from 9 constipated sows (3 in the constipation group and 6 in the 1.0% Gln group) were assessed from gestational day 70 to 84. Comparative analysis showed that the abundance of intestinal-friendly microbiota, that is, Bacteroidetes () and Actinobacteria (), was comparatively increased in the 1.0% Gln group, while the abundance of pernicious bacteria,Oscillospira() andTreponema(), was decreased. Dietary supplementation with 1.0% Gln may ameliorate constipation of sows by regulated endogenous gut microbiota.
The highly polymorphic swine major histocompatibility complex (MHC), termed swine leukocyte antigen (SLA), is associated with different levels of immunologic responses to infectious diseases, vaccines, and transplantation. Pig breeds with known SLA haplotypes are important genetic resources for biomedical research. Canadian Yorkshire and Landrace pigs represent the current specific pathogen-free (SPF) breeding stock maintained in the isolation environment at the Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences. In this study, we identified 61 alleles at five polymorphic SLA loci (SLA-1, SLA-2, SLA-3, DRB1 and DQB1) representing 17 class I haplotypes and 11 class II haplotypes using reverse transcription-polymerase chain reaction (RT-PCR) sequence-based typing (SBT) and PCR-sequence specific primers (PCR-SSP) methods in 367 Canadian SPF Yorkshire and Landrace pigs. The official designation of the alleles have been assigned by the SLA Nomenclature Committee of the International Society for Animal Genetics and released in updated Immuno Polymorphism Database (IPD)-MHC SLA sequence database (Release 2.0.0.3 (2016-11-03)). The submissions confirmed some unassigned alleles and standardized nomenclatures of many previously unconfirmed alleles in the GenBank database. Three class I haplotypes, Hp-37.0, 63.0 and 73.0, appeared to be novel and have not previously been reported in other pig populations. One crossover within the class I region and two between class I and class II regions were observed, resulting in three new recombinant haplotypes. The presence of the duplicated SLA-1 locus was confirmed in three class I haplotypes Hp-28.0, Hp-35.0 and Hp-63.0. Furthermore, we also analyzed the functional diversities of 19 identified frequent SLA class I molecules in this study and confirmed the existence of four supertypes using the MHCcluster method. These results will be useful for studying the adaptive immune response and immunological phenotypic differences in pigs, screening potential T-cell epitopes, and further developing the more effective vaccines.
Background: White matter lesions (WMLs) play a role in cognitive decline and dementia. Little is known about gray matter (GM) changes in WMLs. This study aimed to investigate GM changes in WML patients. Materials and methods: Correlations between altered structural volume and cognitive assessment scores were investigated. GM and white matter (WM) changes in 23 WML-vascular dementia (VaD) patients, 22 WML-non-dementia vascular cognitive impairment (VCIND) patients, and 23 healthy control (HC) subjects were examined. Gray matter density (GMD) was calculated by measuring local proportions of GM at thousands of homologous cortical locations. WM volume was obtained by fully automated software using voxel-based morphometry (VBM). Results: Widespread GMD was significantly lower in WML patients compared to control subjects in cortical and subcortical regions (p<0.05). Greatest differences were found in the bilateral anterior cingulate cortex, inferior frontal gyrus, insula, angular gyrus, caudate, precentral gyrus, and right middle temporal gyrus, right thalamus. Secondary region of interest (ROI) analysis indicated significantly greater GMD in the bilateral caudate among WML-VCIND patients (n=22) compared to HCs (p<0.05). There was a significant difference in WM volume between WML patients and control subjects (p<0.05). Greatest differences were located in the genu/body/splenium of the corpus callosum and superior corona radiata L, and posterior corona radiata L. There was a significant association between structural changes and cognitive scores (Montreal Cognitive Assessment [MoCA] score) (p0.05). Conclusion: GMD and WM volume were changed in WMLs, and the changes were detectable. Correlation between structural changes and cognitive function was promising in understanding the pathological and physiological mechanisms of WMLs.
Swine leukocyte antigen (SLA) class I molecules play a crucial role in generating specific cellular immune responses against viruses and other intracellular pathogens. They mainly bind and present antigens of intracellular origin to circulating MHC I-restricted cytotoxic T lymphocytes (CTLs). Binding of an appropriate epitope to an SLA class I molecule is the single most selective event in antigen presentation and the first step in the killing of infected cells by CD8+ CTLs. Moreover, the antigen epitopes are strictly restricted to specific SLA molecules. In this study, we constructed SLA class I complexes in vitro comprising viral epitope peptides, the extracellular region of the SLA-1 molecules, and β2-microglobulin (β2m) using splicing overlap extension polymerase chain reaction (SOE-PCR). The protein complexes were induced and expressed in an Escherichia coli prokaryotic expression system and subsequently purified and refolded. Specific binding of seven SLA-1 proteins to one classical swine fever virus (CSFV) and four porcine reproductive and respiratory syndrome virus (PRRSV) epitope peptides was detected by enzyme-linked immunosorbent assay (ELISA)-based method. The SLA-1∗13:01, SLA-1∗11:10, and SLA-1∗11:01:02 proteins were able to bind specifically to different CTL epitopes of CSFV and PRRSV and the MHC restrictions of the five epitopes were identified. The fixed combination of Asn151Val152 residues was identified as the potentially key amino acid residues influencing the binding of viral several CTL epitope peptides to SLA-1∗13:01 and SLA-1∗04:01:01 proteins. The more flexible pocket E in the SLA-1∗13:01 protein might have fewer steric limitations and therefore be able to accommodate more residues of viral CTL epitope peptides, and may thus play a critical biochemical role in determining the peptide-binding motif of SLA-1∗13:01. Characterization of the binding specificity of peptides to SLA class I molecules provides an important basis for epitope studies of infectious diseases in swine, and for the rational development of novel porcine vaccines, as well as for detailed studies of CTL responses in pigs used as animal models.
Duck enteritis virus (DEV) can infect ducks, geese, and many other poultry species and leads to acute, septic and highly fatal infectious disease. Autophagy is an evolutionarily ancient pathway that plays an important role in many viral infections. We previously reported that DEV infection induces autophagy for its own benefit, but how this occurs remains unclear. In this study, endoplasmic reticulum (ER) stress was triggered by DEV infection, as demonstrated by the increased expression of the ER stress marker glucose-regulated protein 78 (GRP78) and the dilated morphology of the ER. Pathways associated with the unfolded protein response (UPR), including the PKR-like ER protein kinase (PERK) and inositol-requiring enzyme 1 (IRE1) pathways, but not the activating transcription factor 6 (ATF6) pathway, were activated in DEV-infected duck embryo fibroblast (DEF) cells. In addition, the knockdown of both PERK and IRE1 by small interfering RNAs (siRNAs) reduced the level of LC3-II and viral yields, which suggested that the PERK-eukaryotic initiation factor 2α (eIF2α) and IRE1-x-box protein1 (XBP1) pathways may contribute to DEV-induced autophagy. Collectively, these data offer new insight into the mechanisms of DEV -induced autophagy through activation of the ER stress-related UPR pathway.