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The article presents a study on immune protective effect of orally immunized BALB/c mice with genetic engineered lactobacillus expressed porcine rotavirus A group Vp4 gene. IgG in serum was examined by enzyme-linked immunosorbent assay (ELISA) and SIgA in intestine mucosa and SIgA kit after collected on different days after immunization. Result shows that pW425et-Vp4 recombinant lactobacillus could enhance the immuno-protection ability of the mice.

Genomes of 24 sequenced Bacillus velezensis strains were characterized to identity shared and unique genes of lignocellulolytic enzymes and predict potential to degrade lignocellulose. All 24 strains had genes that encoded lignocellulolytic enzymes, with potential to degrade cellulose and hemicelluloses. Several lignocellulosic genes related to cellulose degradation were universally present, including one GH5 (endo-1,4-β-glucanase), one GH30 (glucan endo-1,6-β-glucosidase), two GH4 (6-phospho-β-glucosidase, 6-phospho-α-glucosidase), one GH1 (6-phospho-β-galactosidase), one GH16 (β-glucanase) and three GH32 (two sucrose-6-phosphate hydrolase and levanase). However, in the absence of gene(s) for cellobiohydrolase, it was predicted that none of the 24 strains would be able to directly hydrolyse cellulose. Regarding genes for hemicellulose degradation, four GH43 (1,4-β-xylosidase; except strain 9912D), one GH11 (endo-1,4-β-xylanase), three GH43 (two arabinan endo-1,5-α-L-arabinosidase and one arabinoxylan arabinofuranohydrolase), two GH51 (α-N-arabinofuranosidase), one GH30 (glucuronoxylanase), one GH26 (β-mannosidase) and one GH53 (arabinogalactan endo-1,4-β-galactosidase) were present. In addition, two PL1 (pectate lyase) and one PL9 (pectate lyase) with potential for pectin degradation were conserved among all 24 strains. In addition, all 24 Bacillus velezensis had limited representation of the auxiliary activities super-family, consistent with a limited ability to degrade lignin. Therefore, it was predicted that for these bacteria to degrade lignin, pretreatment of lignocellulosic substrates may be required. Finally, based on in silico studies, we inferred that Bacillus velezensis strains may degrade a range of polysaccharides in lignocellulosic biomasses. [ABSTRACT FROM AUTHOR]

Bacillus velezensis 157 was isolated from the bark of Eucommia ulmoides, and exhibited antagonistic activity against a broad spectrum of pathogenic bacteria and fungi. Moreover, B. velezensis 157 also showed various lignocellulolytic activities including cellulase, xylanase, α-amylase, and pectinase, which had the ability of using the agro-industrial waste (soybean meal, wheat bran, sugarcane bagasse, wheat straw, rice husk, maize flour and maize straw) under solid-state fermentation and obtained several industrially valuable enzymes. Soybean meal appeared to be the most efficient substrate for the single fermentation of B. velezensis 157. Highest yield of pectinase (19.15 ± 2.66 U g−1), cellulase (46.69 ± 1.19 U g−1) and amylase (2097.18 ± 15.28 U g−1) was achieved on untreated soybean meal. Highest yield of xylanase (22.35 ± 2.24 U g−1) was obtained on untreated wheat bran. Here, we report the complete genome sequence of the B. velezensis 157, composed of a circular 4,013,317 bp chromosome with 3789 coding genes and a G + C content of 46.41%, one circular 8439 bp plasmid and a G + C content of 40.32%. The genome contained a total of 8 candidate gene clusters (bacillaene, difficidin, macrolactin, butirosin, bacillibactin, bacilysin, fengycin and surfactin), and dedicates over 15.8% of the whole genome to synthesize secondary metabolite biosynthesis. In addition, the genes encoding enzymes involved in degradation of cellulose, xylan, lignin, starch, mannan, galactoside and arabinan were found in the B. velezensis 157 genome. Thus, the study of B. velezensis 157 broadened that B. velezensis can not only be used as biocontrol agents, but also has potentially a wide range of applications in lignocellulosic biomass conversion. [ABSTRACT FROM AUTHOR]

The H9N2 avian influenza virus (AIV) has become increasingly concerning due to its role in severe economic losses in the poultry industry. Transmission of AIV to mammals, including pigs and humans, has accelerated efforts to devise preventive strategies. To develop an effective oral vaccine against H9N2 AIV, a recombinant Lactobacillus plantarum NC8 strain expressing the hemagglutinin (HA) gene of H9N2 AIV was constructed in this study. Mice were orally immunized with the recombinant NC8-pSIP409-HA strain, and sIgA, IgG and HI antibodies were produced by the NC8-pSIP409-HA strain, which also induced CD8 + T cell immune responses. Most importantly, oral administration produced complete protection against challenge with mouse-adapted H9N2 virus. These results indicate that the recombinant NC8-pSIP409-HA was more effective at inducing the mucosal, humoral and cellular immune responses. Therefore, L. plantarum NC8-pSIP409-HA could become a promising oral vaccine candidate against H9N2 AIV. [ABSTRACT FROM AUTHOR]

H9N2 subtype, a low pathogenic avian influenza virus, is emerging as a major causative agent circulating poultry workplaces across China and other Asian countries. Increasing case number of interspecies transmissions to mammals reported recently provoked a great concern about its risks inducing global pandemics. In an attempt to understand the underlying mechanism of how the H9N2 virus disrupts the interspecies segregation to transmit to mammals. A mutant H9N2 strain was obtained by passaging the wildtype H9N2 A/chicken/Hong Kong/G9/1997 eight times from lung to lung in BALB/c mice. Our finding revealed that mice manifested severe clinical symptoms including losses of body weight, pathological damages in pulmonary sites and all died within two weeks after infected with the mutated H9N2, whereas all mice survived upon infected with wildtype strain in comparison, which suggested increased pathogenicity of the mutant strain. In addition, mice showed enhanced levels of proinflammatory cytokines in sera, including IL-6, TNF-α and IL-1β compared to those subjected to wildtype viral infections. Sequence analysis showed that five amino acid substitutions occurred at PB2 627 , HA 87, HA 234 , NP 387 and M 156 , and a deletion mutation happened in the M gene (M 157). Of these mutations, PB2 E627K played key roles in modulating lethality in mice. Taken together, the mutant H9N2 strain obtained by serial passaging of its wildtype in mice significantly increased its virulence leading to death of mice, which might be associated the accumulated mutations occurred on its genome. • H9N2 subtype avian influenza virus acquired high virulence via serial 8 passages. • Five amino acid substitutions occurred in mouse-adapted H9N2 virus. • Secretion of proinflammatory cytokines enhanced by the mouse-adapted H9N2 virus. [ABSTRACT FROM AUTHOR]

The functions of the natural dsRNA sensors TLR3 (TRIF) and RIG-I (MAVS) are crucial during viral challenge and have not been accurately clarified in adaptive immune responses to rotavirus (RV) infection. In this study, we found that RV infection caused severe pathological damage to the small intestine of TLR3-/- and TRIF-/- mice. Our data found that dendritic cells from TLR3-/- and TRIF-/- mice had impaired Ag presentation to the RV and attenuated initiation of T cells upon viral infection. These attenuated functions resulted in impaired CD4+ T and CD8+ T function in mice lacking TLR3-TRIF signaling postinfection. Additionally, attenuated proliferative capacity of T cells from TLR3-/- and TRIF-/- mice was observed. Subsequently, we observed a significant reduction in the absolute number of memory T cells in the spleen and mesenteric lymph node (MLN) of TRIF-/- recipient mice following RV infection in a bone marrow chimeric model. Furthermore, there was reduced migration of type 2 classical dendritic cells from the intestine to MLNs after RV infection in TLR3-/- and TRIF-/- mice. Notably, RV infection resulted in attenuated killing of spleen and MLN tissues in TRIF-/- and MAVS-/- mice. Finally, we demonstrated that RV infection promoted apoptosis of CD8+ T cells in TRIF-/- and TLR3-/-MAVS-/- mice. Taken together, our findings highlight an important mechanism of TLR3 signaling through TRIF in mucosal T cell responses to RV and lay the foundation for the development of a novel vaccine., (Copyright © 2024 by The American Association of Immunologists, Inc.)

Interferon (IFN)-λ plays an essential role in mucosal cells which exhibit strong antiviral activity. Lactobacillus plantarum ( L. plantarum ) has substantial application potential in the food and medical industries because of its probiotic properties. Alphacoronaviruses, especially porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV), cause high morbidity and mortality in piglets resulting in economic loss. Co-infection by these two viruses is becoming increasingly frequent. Therefore, it is particularly important to develop a new drug to prevent diarrhea infected with mixed viruses in piglets. In this study, we first constructed an anchored expression vector with CWA (C-terminal cell wall anchor) on L. plantarum . Second, we constructed two recombinant L. plantarum strains that anchored IFN-λ3 via pgsA (N-terminal transmembrane anchor) and CWA. Third, we demonstrated that both recombinant strains possess strong antiviral effects against coronavirus infection in the intestinal porcine epithelial cell line J2 (IPEC-J2). However, recombinant L. plantarum with the CWA anchor exhibited a more powerful antiviral effect than recombinant L. plantarum with pgsA. Consistent with this finding, Lb.plantarum -pSIP-409-IFN-λ3-CWA enhanced the expression levels of IFN-stimulated genes (ISGs) (ISG15, OASL, and Mx1) in IPEC-J2 cells more than did recombinant Lb.plantarum -pSIP-409-pgsA'-IFN-λ3. Our study verifies that recombinant L. plantarum inhibits PEDV and TGEV infection in IPEC-J2 cells, which may offer great potential for use as a novel oral antiviral agent in therapeutic applications for combating porcine epidemic diarrhea and transmissible gastroenteritis. This study is the first to show that recombinant L. plantarum suppresses PEDV and TGEV infection of IPEC-J2 cells.

Objective: To investigate the effect of Trichinella spiralis infection on dectin-2 expression on dendritic cells (DC) in mice., Methods: Seventy-two female BABL/c mice were randomized into experimental and control groups (n=36 in each), and received intragastric administration of 200 muscle larvae of Trichinella spiralis and PBS respectively. Six animals were each sacrificed on days 7, 14, 21, 28, 35 and 42 after administration. The spleen and mesenteric lymph nodes (MLN) were dissected and single cell suspensions were prepared. The expression of dectin-2 on DC in the spleen and MLN was examined by flow cytometry. In another experiment, bone marrow was obtained from C57BL/6 mice, and was treated with granulocyte-macrophage colony-stimulating factor and interleukin 4 to induce bone marrow-derived dendritic cells (BMDC) in vitro. Then 100 μg/ml T. spiralis excretory/secretory (ES) antigen or the same volume of PBS was added. The expression of dectin-2 was determined by flow cytometry at 6, 12, 24, 36 and 48 h., Results: The flow cytometry results showed a significant decrease of dectin-2 expression［（7.0±0.7）%］ on spleen DC compared with that of the control group［（15.1±1.6）%］（P<0.01） on day 7, and significant increase of dectin-2 on MLNDC compared with that of the control on days 7, 21 and 28 ［（11.1±3.5）% vs. （6.6±0.4）%, （12.4±1.4）% vs. （4.9±0.4）%, （6.9±1.0）% vs. （4.0±1.4）%］ （P<0.05） after infection. In vitro results showed that dectin-2 expression was （9.4±2.2）%, （6.9±1.8）%, （6.9±0.7）%, （9.1±1.9）%, and（15.9±1.9）% respectively at 6, 12, 24, 36, and 48 h after ES stimulation on BMDC. The expression at 6, 12, 24 and 36 h decreased significantly in comparison to that of the PBS group［（21.3±6.3）%］（P<0.01)., Conclusion: Trichinella infection can induce changes of dectin-2 expression on DC of mice.

Research on cysticercosis has been stimulated by the rapid development of genomics, proteomics and bioinformatics and the emergence of molecular biological and immunological technologies. In this review, we attempt to discuss the research development on genomics of Taenia solium and candidate vaccines and antigens for cysticercosis. This will provide a new perspective for studying genomics of Taenia solium and for cysticercosis prevention and treatment, and provide a wealth of informative data for the development of novel and highly efficient vaccines against cysticercosis or diagnostic antigen molecules for cysticercosis.

C-type lectins are a group of Ca(2+)-dependent glycan-binding proteins. The C-type lectin receptors (CLRs) recognize carbohydrate ligands in a Ca(2+)-dependent manner. Recent research has demonstrated that CLRs could recognize glycoproteins and activate downstream immune responses. This review summarizes the roles of several CLRs in parasitic infection.

Dendritic cells are the strongest professional antigen-presenting cells. Helminth infection could promote maturation of immature dendritic cells, induce Th2-type immune responses, and inhibit the normal function of dendritic cells which is closely associated with the immune evasion. This paper reviews the role of dendritic cells in host immunity against helminth infections.

A variety of protozoons (Amoeba, Trypanosoma cruzi, Eimeria, Plasmodium falciparum and Toxoplasma gondii, etc.) can activate and regulate the human immune system, change tumor-induced immunosuppression, and enhance the anti-tumor immune response. This paper reviews the effects of protozoon on cellular and humoral immunity, the tumor microenvironment in tumor-bearing organisms, and reveals the antitumor immune mechanisms of protozoon.

Dendritic cells are a major class of professional antigen-presenting cells which play an important role in the immune response of parasite-infected host. This article summarizes the role of dendritic cells in the immunity to parasitic infection by analyzing the studies of protozoan, nematode, and trematode infections.

Regulatory T cells (Tregs), a class of CD4+ T lymphocytes which are different from the Th1 and Th2 lymphocytes, have immunosuppressive function and play an important role in maintaining immune homeostasis and immune tolerance. Previous studies showed that the generation of Tregs could be induced, and Tregs reduced the immune pathological damage to the host by inhibiting T-cell function in helminth infection.

Trichinosis caused by Trichinella spiralis is a parasitic zoonosis with world-wide distribution, which impacts on the development of animal husbandry and food safety, and thus threatens human health. T. spiralis has the ability to evade the host immune response, which results in forming a long-term infection in the host. The previous studies indicated that a changed host immune state due to T. spiralis was an important reason for the evasion. Among the factors, cytokines, dendritic cells and regulatory T cells played an important role in the regulation of the host immune process.

Objective: To construct the recombinant fowlpox virus expressing Eimeria tenella F2 hybrid strain SO7 gene., Methods: A recombinant expression plasmid pUTA-SO7 was constructed by inserting the SO7 gene of Eimeria tenella F2 hybrid strain into downstream of a hybrid poxvirus promoter which was flanked by the TK gene of fowlpox virus (FPV). The constructed pUTA-SO7 was firstly transfected into chicken embryo fibroblast cells(CEF) pre-infected with FPV strain 282E4 by using liposome, then the viruses resulted from the transfection were selected for 2 passages by culturing in CEF cells with MEM medium containing 40 mg/L 5-bromo-2-deoxy-uridine (BrdU). The selected viruses were plaque-purified in CEF cultured with MEM medium without BrdU. RESULTS Polymerase chain reaction (PCR), indirect immunofluorescence assay and Western blotting showed that S07 gene was expressed in recombinant fowlpox virus., Conclusion: The recombinant FPV (rFPV) expressing the SO7 gene has been obtained.

Objective: To explore the effect of soybean isoflavone on the cognitive function in ovariectomized mice and to study the cognitive function mechanism of soybean isoflavone., Methods: Forty-five Kunming female mice were randomly assigned into 5 groups: A (sham operated); B (ovariectomized, OVX); C (OVX + low dose soybean isoflavone); D (OVX + moderate dose soybean isoflavone); and E (OVX + high dose soybean isoflavone). The experiment lasted 60 days., Results: Ovariectomy significantly elongated the destination time of water maze, shortened the latent time of step-down test, decreased SOD of serum and Na+ K+ -ATPase and Ca2+ Mg2+ -ATPase of brain, and increased malonaldehyde of serum and monoamine oxidase of brain, which-could be inhibited by soybean isoflavone consumption., Conclusion: The continuous oral administration of soybean isoflavone can improve the cognitive function of ovariectomized mice.