Molecular structure, expression, and bioactivity of B-cell-activating factor of the TNF family (BAFF) and its receptor BAFF-R in cats (Felis catus)

Engineered fibrotic liver-targeted truncated transforming growth factor β receptor type II variant for superior anti-liver fibrosis therapy

Truncated transforming growth factor β receptor type II (tTβRII) is a promising anti-liver fibrotic candidate because it serves as a trap for binding excessive TGF-β1 by means of competing with wild type TβRII (wtTβRII). However, the widespread application of tTβRII for the treatment of liver fibrosis has been limited by its poor fibrotic liver-homing capacity. Herein, we designed a novel tTβRII variant Z-tTβRII by fusing the platelet-derived growth factor β receptor (PDGFβR)-specific affibody Z_PDGFβR to the N-terminus of tTβRII. The target protein Z-tTβRII was produced using Escherichia coli expression system. In vitro and in vivo studies showed that Z-tTβRII has a superior specific fibrotic liver-targeting potential via the engagement of PDGFβR-overexpressing activated hepatic stellate cells (aHSCs) in liver fibrosis. Moreover, Z-tTβRII significantly inhibited cell migration and invasion, and downregulated fibrosis- and TGF-β1/Smad pathway-related protein levels in TGF-β1-stimiluated HSC-T6 cells. Furthermore, Z-tTβRII remarkably ameliorated liver histopathology, mitigated the fibrosis responses and blocked TGF-β1/Smad signaling pathway in CCl₄-induced liver fibrotic mice. More importantly, Z-tTβRII exhibits a higher fibrotic liver-targeting potential and stronger anti-fibrotic effects than either its parent tTβRII or former variant BiPPB-tTβRII (PDGFβR-binding peptide BiPPB modified tTβRII). In addition, Z-tTβRII shows no significant sign of potential side effects in other vital organs in liver fibrotic mice. Taken together, we conclude that Z-tTβRII with its a high fibrotic liver-homing potential, holds a superior anti-fibrotic activity in liver fibrosis in vitro and in vivo, which may be a potential candidate for targeted therapy for liver fibrosis.

Functional characterization of complement factor H in host defense against bacterial pathogen in Nile tilapia (Oreochromis niloticus)

Complement factor H (CFH), a multifunctional soluble complement regulatory protein, can bind to a variety of pathogens and play a crucial role in host innate immune defense. To explore the functional characteristics of CFH (OnCFH) in Nile tilapia (Oreochromis niloticus), we cloned and characterized the open reading frame (ORF) of OnCFH in this study. The full-length of OnCFH ORF is 1359 bp, encoding 452 aa for a 48.85 kDa peptide, and its predicted structure containing six short complement-like repeats (SCRs). The analysis of tissue distribution showed that OnCFH was constitutively expressed in all tested tissues, with the highest in the liver. Upon Streptococcus agalactiae and Aeromonas hydrophila stimuli in vivo and in vitro, OnCFH mRNA transcript was significantly upregulated in head kidney tissue as well as head kidney monocytes/macrophages. Further, the recombinant OnCFH protein ((r)OnCFH) could bind to pathogenic bacteria in a dose-dependent. Moreover, it got involved in the regulation of inflammation as well as phagocytosis of monocytes/macrophages. The knockdown of OnCFH remarkably decreased the amount of bacteria in the head kidney. In summary, our data demonstrated that OnCFH could participate in the immune response of Nile tilapia against bacterial infection.

IL-35, TNF-α, BAFF, and VEGF serum levels in patients with different rheumatic diseases

Objectives

Inflammatory processes in rheumatic diseases spread via various types of immune system cells and tissues with the aid of inflammatory cytokines and growth factors and the participation of vascular endothelium. Research is still conducted to determine the role of individual factors in the pathophysiology of rheumatic diseases. The task is complicated because the multiplane network of cytokines is characterized by complex correlations manifesting as positive and negative feedback, which impedes the definitive interpretation of the role of specific cytokines. Therefore, it seems justified to perform a comparative analysis of the expression of at least several molecules in one study, which may help reveal their role in the pathogenesis of rheumatic diseases and have prognostic value.

Material and methods

The aim of the study involves the assessment and comparative analysis of the concentrations of interleukin 35 (IL-35), tumour necrosis factor α (TNF-α), B-cell-activating factor (BAFF), and vascular endothelial growth factor (VEGF) in peripheral blood serum in patients with rheumatoid arthritis (RA) (n = 43), systemic lupus erythematosus (SLE) (n = 28), antiphospholipid syndrome (APS) (n = 24), and mixed connective tissue disease (MCTD) (n = 9). The main intention is to search for biomarkers for specific rheumatic diseases. Cytokine and growth factor levels were determined using specific ELISA kits.

Results

Statistically significant differences in VEGF and IL-35 concentrations occurred between patients with APS vs. RA and SLE vs. RA. There was a significant high positive correlation between the concentration of BAFF and TNF-α (r = 0.77, p < 0.0000) in patients with APS, as well as in patients with SLE (r = 0.55, p = 0.00).

Conclusions

BAFF and TNF-α may be promising biomarkers in patients with APS and VEGF in patients with RA. Additionally, IL-35 may be a useful marker for the diagnosis of APS. Positive correlation of BAFF and TNF-α concentrations in APS and SLE potentially indicates much more similar etiopathogenesis of these diseases than it could be previously predicted.