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• Cat (Felis catus) BAFF and its receptor BAFF-R were cloned. • csBAFF, EGFP/csBAFF, and cBAFF-R were expressed in E. coli and purified using a Ni2+ column. • csBAFF cellular localization was assessed. • csBAFF promoted B-cell survival in vitro. • Ligand–receptor interaction was assessed. B-cell survival depends on signals induced by binding of B-cell activating factor (BAFF) to its receptor (BAFF-R). In this study, the full-length cDNAs of cat BAFF (cBAFF) and BAFF-R (cBAFF-R) were amplified from the spleen by reverse transcription PCR. The open reading frame of cBAFF cDNA encodes a protein of 285 amino acids containing a predicted transmembrane domain and a furin protease cleavage site, similar to mammalian, avian, and reptile BAFFs. The cBAFF-R gene encodes a 189 amino acid protein. Real-time quantitative PCR analyses revealed that the two genes are predominantly expressed in the spleen. csBAFF, EGFP/csBAFF, and cBAFF-R were efficiently expressed in Escherichia coli BL21 (DE3), as confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analyses. After purification, the EGFP/csBAFF fusion protein showed a fluorescence spectrum similar to that of EGFP. Confocal laser scanning microscopy showed that EGFP/csBAFF bound to its receptor. In vitro , csBAFF promoted the survival of cat and mouse splenic B cells with/without a priming agent (Staphylococcus aureus Cowan 1, SAC) or anti-mouse IgM. Furthermore, it stimulated the survival of mouse B cells, similar to msBAFF. Recombinant cBAFF-R blocked the function of sBAFF in vitro. These findings indicate that csBAFF plays an important role in the survival of cat B cells and has functional cross reactivity between cats and other mammals, and suggest a role for the BAFF–BAFF-R system in regulating B-cell survival. Therefore, BAFF and BAFF-R show promise for enhancing the immune systems of animals. [ABSTRACT FROM AUTHOR]

B cell-activating factor (BAFF)is a member of the tumor necrosis factor (TNF) family and plays roles in B cell survival and maturation. In this study, the full-length cDNA of Nile tilapia ( Oreochromis niloticus ) BAFF (tBAFF) was amplified from the spleen by reverse transcription PCR (RT-PCR). The open reading frame of this cDNA encodes a protein of 261 amino acids containing a predicted transmembrane domain and a furin protease cleavage site, similar to mammalian, avian, and reptile BAFF. Real-time quantitative PCR (qPCR) analysis revealed that tBAFF is present in various tissues and is predominantly expressed in the spleen. The predicted three-dimensional (3D) structure of the Nile tilapia ( Oreochromis niloticus ) soluble BAFF (tsBAFF) monomer was determined by (3D) structure modeling monomeranalyzed by (3D) structure mouse counterpart. Both tsBAFF and EGFP/tsBAFF were efficiently expressed in Escherichia coli BL21 (DE3), as confirmed by SDS-PAGE and Western blot analysis. After purification, the EGFP/tsBAFF fusion protein showed a fluorescence spectrum similar to that of EGFP. Laser scanning confocal microscopy showed that EGFP/tsBAFF bound to its receptor. In vitro , tsBAFF promoted the proliferation of Nile tilapia and mouse splenic B cells together with/without a priming agent ( Staphylococcus aureus Cowan 1, SAC) or anti-mouse IgM. Furthermore, tsBAFF showed a similar proliferation-stimulating effect on mouse B cells compared to msBAFF. These findings indicate that tsBAFF plays an important role in the proliferation of Nile tilapia B cells and has functional cross-reactivity among Nile tilapia and mammals. Therefore, BAFF may represent a useful factor for enhancing immunological efficacy in animals. [ABSTRACT FROM AUTHOR]

The enzyme gamma-interferon-inducible lysosomal thiol reductase (GILT) plays a role in facilitating the processing and presentation of major histocompatibility complex (MHC) class II-restricted antigens and is also involved in MHC I-restricted antigens in adaptive immunity catalyzing disulfide bond reduction in mammals. In this study, we cloned a GILT gene homolog from largemouth bass (designated ‘lbGILT’), a freshwater fish belonging to Perciformes and known for its nutritive value. We obtained the full-length cDNA of lbGILT by reverse transcription PCR and rapid amplification of cDNA ends. This cDNA is comprised of a 5'-untranslated region (UTR) of 87 bp, a 3′-UTR of 189 bp, and an open reading frame of 771 bp. It encodes a protein of 256 amino acids with a deduced molecular weight of 28.548 kDa and a predicted isoelectric point of 5.62. The deduced protein possesses the typical structural features of known GILTs, including an active site motif, two potential N-linked glycosylation sites, a GILT signature sequence, and six conserved cysteines. Tissue-specific expression of lbGILT was shown by real-time quantitative PCR. The expression of lbGILT mRNA was obviously up regulated in spleen and kidney after induction with lipopolysaccharide. Recombinant lbGILT was produced as an inclusion body with a His 6 tag in ArcticExpress (DE3), and the protein was then washed, solubilized, and refolded. The refolded lbGILT showed reduction activity against an IgG substrate. These results suggest that lbGILT plays a role in innate immunity. [ABSTRACT FROM AUTHOR]

Abstract: Interferon-γ-inducible-lysosomal thiol reductase (GILT) plays a key role in the processing and presentation of MHC class II-restricted antigen (Ag) by catalyzing disulfide bond reduction, thus unfolding native protein Ag and facilitating subsequent cleavage by proteases. In this study, we reported the cloning of a GILT gene homologue from chicken (designated cGILT). The open reading frame (ORF) of cGILT consists of 762 bases, encoding a protein of 253 amino acids, with a putative molecular weight of 28kDa. The deduced protein possesses the typical structural feature of known GILT proteins, including an active-site motif, a GILT signature sequence, and 6 conserved cysteines. Genomic analysis revealed that cGILT gene, spanning a 1868bp fragment, contained seven exons interrupted by six introns. The result of real-time PCR showed that cGILT mRNA was expressed in a tissue-specific manner, while the cGILT mRNA expression was obviously up-regulated in spleen and PBMCs after stimulation with lipopolysaccharide (LPS). After expression as a soluble protein in Escherichia coli and purification by Ni-NTA affinity chromatography, cGILT was demonstrated to exhibit thiol reductase activity on IgG substrate. [Copyright &y& Elsevier]

Abstract: B cell activating factor (BAFF), a member of the tumor necrosis factor family, is critical to B cell survival, proliferation, maturation, and immunoglobulin secretion and to T cell activation. In the present study, the full-length cDNA of BAFF from the South African clawed frog (Xenopus laevis, designated xlBAFF) was cloned using rapid amplification of cDNA ends (RACE) techniques and RT-PCR. The full-length cDNA of xlBAFF consists of 1204 bases including an open reading frame (ORF) of 801 nucleotides that are translated into a predicted 266 amino acid protein. Sequence comparison indicated that the amino acids of xlBAFF possessed the TNF signature, including a transmembrane domain, a putative furin protease cleavage site and three cysteine residues. The predicted three-dimensional (3D) structure of the xlBAFF monomer revealed that it was very similar to its counterparts. Real-time quantitative PCR analysis revealed that xlBAFF could be detected in various tissues and predominantly expressed in the spleen and other lymphoid tissue. The soluble xlBAFF had been cloned into a pET28a vector to express the recombinant protein. The His6-xlBAFF was efficiently expressed in Escherichia coli. BL21 (DE3) and its expressions were confirmed by SDS-PAGE and Western blotting analysis. After purification, laser scanning confocal microscopy analysis showed that xlBAFF could bind to its receptors on B cells. CCK-8 assays revealed that xlBAFF is not only able to promote survival/proliferation of South African clawed frog lymphocytes but also able to stimulate survival/proliferation of mouse B cells. These results will allow for further investigation the use of X. laevis as an in vivo model for related studies. [Copyright &y& Elsevier]

Abstract: B cell activating factor (BAFF), belonging to the tumor necrosis factor (TNF) family, plays an important role in B cell survival, proliferation and differentiation. In the present study, we amplified the cDNA of dog (Canis familiaris) BAFF (designated doBAFF) from spleen by reverse transcription-PCR (RT-PCR) and rapid amplification of cDNA ends (RACE) strategies. The open reading frame (ORF) of doBAFF covers 879bp encoding 292 amino acids, with a 152-aa mature peptide. The soluble mature part of doBAFF (dosBAFF) shares 91.5%, 72.1%, 96.7%, 94.0% and 91.5% identity with the human, mouse, cattle, pig and rabbit counterparts, respectively. The predicted three-dimensional (3D) structural analysis of dosBAFF analyzed by “comparative protein modeling” revealed that it was very similar to its human counterpart. Real-time quantitative PCR analysis revealed that doBAFF was mainly expressed in spleen. Two fusion proteins SUMO-dosBAFF and GFP/dosBAFF were efficiently expressed in Escherichia coli BL21 (DE3) and purified using metal chelate affinity chromatography (Ni-NTA). Laser scanning confocal microscopy analysis showed that GFP/dosBAFF could bind to the mouse splenic B-cell. In vitro, SUMO-dosBAFF and GFP/dosBAFF were able to promote the survival/proliferation of dog lymphocytes or mouse splenic B cells with/without anti-IgM. Therefore, BAFF may be a potential immunologic factor for enhancing immunological efficacy in dog. [Copyright &y& Elsevier]

Abstract: B-cell activating factor of the TNF family (BAFF) induces B-cell survival, proliferation, immunoglobulin secretion and plays a role in enhancing immune responses. In the present study, a BAFF homolog has been identified in mefugu Takifugu obscurus, and its biological activities have been characterized. The mefugu BAFF (fBAFF) cDNA is 789 bp in length and translates into a 262-aa protein. The fBAFF genomic sequence consists of six exons and five introns, is approximately 1.8 kb in size. Amino acid sequence comparison indicated that fBAFF possessed the TNF signatures, a transmembrane domain, a putative furin protease cleavage site and three cysteine residues, which were the typical characteristics of TNF gene in mammals and birds. The predicted three-dimensional (3D) structure of the fsBAFF monomer analyzed by comparative protein modeling revealed that it was very similar to its human counterpart. Real-time quantitative PCR (qPCR) analysis revealed that fBAFF was predominantly expressed in mefugu lymphoid tissue spleen. The SUMO-fsBAFF and GFP/fsBAFF efficiently expressed in Escherichia coli Rosetta (DE3) were confirmed by SDS-PAGE and Western blotting analysis. After purification, the GFP/fsBAFF fusion protein obtained similar fluorescence spectrum to those of GFP. Laser scanning confocal microscopy analysis showed GFP/fsBAFF could bind to its receptors. In vitro, the MTT assays and flow cytometric analysis indicated that SUMO-fsBAFF could promote the proliferation of mefugu splenocytes or mouse splenic B cells together with/without anti-mouse IgM. These findings indicate that SUMO-fsBAFF plays an important role in proliferation of mefugu B cells and has functional cross-reactivity among mefugu and other mammalians. Therefore, BAFF may be a potential immunologic factor for enhancing immunological efficacy in fish. [Copyright &y& Elsevier]

It is important to understand the mechanism of toluene absorption by phosphonium ionic liquids (PILs) for volatile organic compound removal with ionic liquids. In this work, the molecular structures of trimethyl(butyl)phosphonium tetrafluoroborate ([P 1114 [BF 4), trimethyl(butyl)phosphonium bis(trifluoromethylsulfonyl)imide ([P 1114 [Tf 2 N]), tributyl(propyl)phosphonium tetrafluoroborate ([P 4443 [BF 4) and tributyl(propyl)phosphonium bis(trifluoromethylsulfonyl)imide ([P 4443 [Tf 2 N]) were optimized by quantum chemical calculations at the GGA/PW91 level with the DNP basis set of density functional theory (DFT). The most stable configurations for toluene absorption by these PILs with multiple sites were also obtained by calculation under the same conditions. The main parameters for the most stable structure, data for the Mulliken charge and frontier molecular orbitals were further determined and discussed. It was found that the interactions of PILs with toluene are mainly composed of hydrogen bonds, C-H···π bond interactions and electrostatic attraction, and most of the calculated frontier molecular orbitals are concentrated on the toluene molecule. Additionally, analysis showed that [BF 4 − is inclined to form hydrogen bonds with cations and the methyl groups of toluene, and [Tf 2 N]− tends to attract toluene via electrostatic attraction. Investigation of the absorption energy with multiple sites indicated that PILs have great performance for toluene absorption. Analysis of the ionic size and geometric structure of the PILs demonstrated that the space available for accommodating toluene is an important condition for toluene absorption and is mainly provided by cations. In particular, PILs with cations having suitable long alkyl side chains show excellent capacity for toluene absorption. Moreover, NBO and AIM analyses confirmed the existence of weak closed-shell interactions (hydrogen bonds and C-H···π bonds) between toluene and PILs. The experimental results obtained for the static toluene absorption by the PILs provide a great supplement and confirmation of the calculations [Display omitted] • Structure of phosphonium cation is conducive for multiple sites absorption. • Space for accommodating toluene is mainly provided by phosphonium cation. • Suitable long alkyl chain is necessary for the high toluene absorption. • Static toluene absorption amount for [P 8883 [BF 4 is as high as 2840 mg/g. [ABSTRACT FROM AUTHOR]