Identification and functional analysis of NOD2 and its two splicing variants associated with a novel pattern of signal regulation in teleost fishes.

The nucleotide-binding oligomerization domain 2 (NOD2) has been identified as an important sensor for microorganic invasion in both mammals and teleost fishes. In this study, two splicing variants of NOD2 (NOD2-v1 and NOD2-v2) were identified as truncating the functional domains of wild-type NOD2 in the teleost fish Schizothorax prenanti. NOD2-v1 included an intron sequence that terminated within the third leucine-rich repeat (LRR) domain, while NOD2-v2 incorporated an insertion of one and half intron sequences and truncated within the second caspase activation and recruitment domain (CARD). NOD2, NOD2-v1 and NOD2-v2 genes were ubiquitously expressed. All three genes positively responded to exposure of Aeromonas hydrophila and lipopolysaccharide stimulation in varying degrees. Using luciferase activity assays in HEK293T cells, our results revealed that NOD2 activated the NF-κB signal and recognized muramyl dipeptide (MDP). NOD2-v1 exhibited deficiency in the LRR domains and could not sense MDP, but maintained the ability to activate NF-κB and enhanced NOD2-mediated MDP recognition. Given the significant change to the functional structure, NOD2-v2 lost its capacity for NF-κB activation, but interestingly repressed NOD2-mediated MDP sensing and NF-κB activation, and even NOD2-v1-induced NF-κB activation. Altogether, our study reveals a novel pattern of signal regulation by splicing variants in teleost fishes.

[Fast Start-up of SBAF System Assisted CANON Process and the Microbial Analysis].

Long period start-up is one of the main restraining factors of the single-stage completely autotrophic nitrogen removal over nitrite (CANON) process.This study investigated the fast start-up of the CANON process initiated by a submerged biological aerated filter (SBAF) method.With conventional activated sludge from the secondary sedimentation tank of municipal waste water treatment plants as the seed sludge,the CANON process was successfully started up after the acclimation of sludge microorganisms for 48 days under the experimental conditions of (30±2)℃,organic carbon free and controlled dissolved oxygen (stage Ⅰ:0.3-0.5mg·L-1;stage Ⅱ-Ⅳ:0.1-0.2mg·L-1),with the maximum removal rates of ammonia nitrogen and total nitrogen achieved at 99.9% and 86.5%,respectively.The population structure characteristics of microorganisms in the system were studied using high-throughput sequencing of 16S rDNA amplicon.The results demonstrated that the two dominant microbial strains in the system were Proteobacteria and Planctomycetes,accounting for 26.6% and 17.8%,respectively.The major contributors of nitrogen removal were Nitrosomonas in ß-Proteobacteria and Candidatus brocadia in Brocadiae.Through the above experiments,it was revealed that the investigated SBAF based CANON possesses had the advantages of fast start-up,efficient biological nitrogen removal and stable operation process.

High levels of soluble herpes virus entry mediator in sera of patients with allergic and autoimmune diseases

Herpes virus entry mediator (HVEM) is a newly discovered member of the tumor necrosis factor receptor (TNFR) superfamily that has a role in herpes simplex virus entry, in T cell activation and in tumor immunity. We generated mAb against HVEM and detected soluble HVEM (SHVEM) in the sera of patients with various autoimmune diseases. HVEM was constitutively expressed on CD4(+)and CD8(+)T cells, CD19(+)B cells, CD14(+)monocytes, neutrophils and dendritic cells. In three-way MLR, mAb 122 and 139 were agonists and mAb 108 had blocking activity. An ELISA was developed to detect sHVEM in patient sera. sHVEM levels were elevated in sera of patients with allergic asthma, atopic dermatitis and rheumatoid arthritis. The mAbs discussed here may be useful for studies of the role of HVEM in immune responses. Detection of soluble HVEM might have diagnostic and prognostic value in certain immunological disorders.