Xianlong Ye

Synergistic effects of interleukin-1β and interleukin-17A antibodies on collagen-induced arthritis mouse model.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that mainly causes the synovial joint inflammation and cartilage destruction. Both interleukin-1β (IL-1β) and Interleukin-17 (IL-17) are important proinflammatory cytokines involved in the pathogenesis of RA. We investigated whether combination therapy with IL-1β and IL-17A antibodies would generate the potential for synergistic effects on a collagen-induced arthritis (CIA) mouse model. Mice with CIA were subcutaneously injected with humanized IL-1β antibody, IL-17A antibody, or combination treatment. The effects of treatment were determined by arthritis severity score, histological damage and bone destruction, autoreactive humoral and cellular immune responses and cytokine production. Treatment with IL-1β antibody or IL-17A antibody alone resulted in beneficial effects on clinical and histological parameters of CIA mice. Compared with the single antibody treatments, the combination therapy resulted in a more significant effect in alleviating the severity of arthritis by preventing bone damage and cartilage destruction, reducing humoral and cellular immune responses, and down-regulating the expression of IL-1β, IL-6, IL-17A, IFN-γ, RANKL and MMP-3 in inflammatory tissue. In conclusion, combination treatment with humanized IL-1β and IL-17A antibodies demonstrates synergistic beneficial effects for preventing joint inflammation and cartilage destruction and bone damage in CIA mice model. These studies also provide evidence that combination with IL-1β and IL-17A antibodies may lead to a new combinatorial therapy for RA patients.

A bispecific antibody against IL-1β and IL-17A is beneficial for experimental rheumatoid arthritis.

IL-1β is a pivotal cytokine and plays an important role in rheumatoid arthritis (RA). More recently, the biological therapy targeting this cytokine has been impressively effective for many RA patients, however, it remains insufficient in some patients. One of the reasons for these failures may be due to multiple cytokines involved in the disease process. In the present study, we constructed a single-chain bispecific antibody (scBsAb1/17) against both human IL-1β and human IL-17A which is the mediator for several key cytokines involved in the RA process such as TNF- and IL-6. A number of in vitro assays demonstrated that scBsAb1/17 simultaneously bound to both targets with a similar antigen-binding affinity as an individual single-chain antibody molecule (anti-IL-1β scFv or anti-IL-17A scFv). Mice with collagen-induced arthritis (CIA) were administrated with either scBsAb1/17 or individual single chain antibody alone, and we noticed that treatment with scBsAb1/17 significantly ameliorated clinical signs and alleviated histological lesion of CIA mice compared to treatments with anti-IL-1β scFv or anti-IL-17A scFv alone. Production of CII-specific antibodies in scBsAb1/17-treated CIA mice was substantially lower than that of single-chain antibody-treated CIA mice. In addition, scBsAb1/17 was more potent in the inhibition of collagen-specific proliferation of splenocytes and mRNA expression of TNF-, IL-6, IL-2, IL-1β and IFN-γ in the spleens of CIA mice compared to a single-chain antibody alone. These results suggest that scBsAb1/17 appears more beneficial in CIA mice than monovalent single-chain antibody molecules.

FGF21 treatment ameliorates alcoholic fatty liver through activation of AMPK-SIRT1 pathway

Fibroblast growth factor 21 (FGF21), a recently identified member of the FGF superfamily, is mainly secreted from the liver and adipose tissues and plays an important role in improving metabolic syndrome and homeostasis. The aim of this study is to evaluate the role of FGF21 in alcoholic fatty liver disease (AFLD) and to determine if it has a therapeutic effect on AFLD. In this paper, we tested the effect of FGF21 on alcohol-induced liver injury in a murine model of chronic ethanol gavage and alcohol-treated HepG2 cells. Male KM mice received single dose of 5 g/kg ethanol gavage every day for 6 weeks, which induced significant fatty liver and liver injury. The alcohol-induced fatty liver cell model was achieved by adding ethanol into the medium of HepG2 cell cultures at a final concentration of 75 mM for 9 days. Results showed that treatment with recombinant FGF21 ameliorated alcoholic fatty liver and liver injury both in a murine model of chronic ethanol gavage and alcohol-treated HepG2 cells. In addition, FGF21 treatment down-regulated the hepatic expression of fatty acid synthetic key enzyme, activated hepatic AMPK-SIRT1 pathway and significantly down-regulated hepatic oxidative stress protein. Taken together, FGF21 corrects multiple metabolic parameters of AFLD in vitro and in vivo by activation of the AMPK-SIRT1 pathway.

Long-acting hypoglycemic effects of PEGylated FGF21 and insulin glargine in mice with type 1 diabetes

OBJECTIVE In this study, we compared the long-acting hypoglycemic effect of PEGylated FGF21 (PEG-FGF21) with insulin glargine in mice with STZ-induced type 1 diabetes. METHODS PEG-FGF21 and insulin glargine were administered once daily for two months, and blood glucose was measured prior to the next administration. Real-time PCR was used to measure mRNA expression of glucokinase (GK), glucose 6-phosphatase (G6pase), phosphoenolpyruvate carboxykinase (PEPCK), glucose transporter 1 (GLUT1) and glucose transporter 4 (GLUT4). RESULTS During long-term treatment, the blood glucose of untreated mice remained at 25.0 to 28.0mmol/L for the whole experiment, and the blood glucose of mice treated with insulin glargine remained at 16.5 to 18.0mmol/L. However, mice treated with PEG-FGF21 had lower blood glucose levels of 8.0 to 9.0mmol/L on day 10 and maintained this level until the end of the experiment. qRT-PCR showed that PEG-FGF21 up-regulated mRNA expression of GK and GLUT1, and down-regulated mRNA expression of G6Pase and PEPCK. Insulin glargine up-regulated mRNA expression of GLUT4, but had no effect on GK, G6Pase, PEPCK or GLUT1. CONCLUSIONS PEG-FGF21 has a better long-acting efficacy than insulin glargine. PEG-FGF21 achieves glucose clearance by accelerating glycolysis by up-regulating expression of GK and GLUT1 and inhibiting gluconeogenesis via down-regulation of G6Pase and PEPCK expression.

Pharmacological efficacy of anti-IL-1β scFv, Fab and full-length antibodies in treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that mainly causes the synovial joint inflammation and cartilage destruction. Interleukin-1β (IL-1β) is an important proinflammatory cytokine involved in the pathogenesis of RA. In this study, we constructed and expressed anti-IL-1β-full-length antibody in CHO-K1-SV, anti-IL-1β-Fab and anti-IL-1β-scFv in Rosetta. We compared the therapeutic efficacy of three anti-IL-1β antibodies for CIA mice. Mice with CIA were subcutaneously injected with humanized anti-IL-1β-scFv, anti-IL-1β-Fab or anti-IL-1β-full-length antibody. The effects of treatment were determined by arthritis severity score, autoreactive humoral, cellular immune responses, histological lesion and cytokines production. Compared with anti-IL-1β-scFv treatments, anti-IL-1β-Fab and anti-IL-1β-full-length antibody therapy resulted in more significant effect in alleviating the severity of arthritis by preventing bone damage and cartilage destruction, reducing humoral and cellular immune responses, and down-regulating the expression of IL-1β, IL-6, IL-2, IFN-γ, TNF-α and MMP-3 in inflammatory tissue. The therapeutic effects of anti-IL-1β-Fab and anti-IL-1β-full-length antibodies on CIA mice had no significant difference. However, production of anti-IL-1β-full-length antibody in eukaryotic system is, in general, time-consuming and more expensive than that of anti-IL-1β-Fab in prokaryotic systems. In conclusion, as a small molecule antibody, anti-IL-1β-Fab is an ideal candidate for RA therapy.

Enhancement of the Pharmacological Efficacy of FGF-21 by Genetic Modification and PEGylation

FGF-21 is a potential candidate for the treatment of type 2 diabetes mellitus. However, the clinical application of wild-type human FGF-21 is challenging due to some limitations, such as its poor hypoglycemic potency and short in vivo half-life. In this paper, we have produced an FGF-21 mutant (ahmFGF-21) by exchanging the functional domain of hFGF-21 with that of mFGF-21 to improve the potency of FGF-21. Results showed that the ahmFGF-21 protein was more potent than wild-type hFGF-21 in stimulating glucose uptake in vitro and lowering blood glucose levels of diabetic animals. To decrease its immunogenicity and increase its biostability, the N-terminus of ahmFGF-21 was modified in a sitespecific manner with 20 kDa mPEG-propionaldehyde (mPEG-ALD). We found that the preservation time of ahmFGF-21 in vitro was significantly prolonged after PEGylation. The serum antibody levels against ahmFGF-21 in immunized rabbits with the PEGylated ahmFGF-21 were significantly reduced than those with the unmodified ahmFGF-21, and the target protein concentration in the rabbits administrated with the PEGylated ahmFGF-21 increased 9.5-fold higher than that of the unmodified ahmFGF-21. The animal experimental results showed that PEGylation of ahmFGF-21 enhanced the hypoglycemic effect in diabetic mice. These results suggest that the in vitro and in vivo hypoglycemic effects of FGF-21 are significantly enhanced by genetic modification and the metabolic pharmacology of FGF-21 in type 2 diabetic mice is improved by PEGylation at a specific site.

Comparison of PEGylated FGF-21 with insulin glargine for long-lasting hypoglycaemic effect in db/db mice

AIM This study investigated the long-acting antidiabetic efficacy of PEGylated fibroblast growth factor (FGF)-21 in type 2 diabetic db/db mice. METHODS PEGylated FGF-21 was prepared by modifying the N-terminus of human FGF-21 (hFGF-21) using mPEG-ALD. To compare the long-lasting hypoglycaemic effects of PEGylated FGF-21 and insulin glargine in diabetic db/db mice, their pharmacological efficacy was evaluated by changes in blood glucose levels, body weight, insulin levels, glycosylated haemoglobin levels, lipid profile and liver function parameters, and by oral glucose tolerance tests (OGTTs). RESULTS Both PEGylated FGF-21 and insulin glargine decreased plasma glucose in db/db mice. However, compared with insulin glargine treatment, PEGylated FGF-21 therapy had more significant effects in lowering blood glucose and glycosylated haemoglobin levels, improving lipid profile and liver function parameters, alleviating insulin resistance and reducing the glucose area under the curve in OGTTs. CONCLUSION Our results suggest that PEGylated FGF-21 is an ideal candidate as a long-acting antidiabetes drug, and holds significant promise as an effective therapeutic agent in the treatment of type 2 diabetes patients.

A Neutralization scFv Antibody against IL-1β Isolated from a NIPA-based Bacterial Display Library

OBJECTIVE RA is one of autoimmune diseases, has drawn great attention of the world. Currently, the anti- IL-1β monoclonal antibody Canakinumab (ACZ885) for treatment of RA has entered into clinical trials. However, Full length antibody has large molecular weight, and is difficult to penetrate the tissue or the nidus. In contrast, scFv has low molecular weight and strong penetration ability, and is favorable to increase the drug concentration in the indus, hence improving the efficacy of the drug. The aim of this study is to obtain a neutralizing scFv antibody from a combinatorial scFv library against hIL-1β by the modified NLPA-based bacterial display system, for further development of the small molecule antibody drug for treatment of RA. METHODS The modified NIPA-based bacterial display system was used to construct the combinatorial scFv library derived from the spleen cDNA of immunized mice with hIL-1β. FACS was used to screen hIL- 1β-binding clones with FITC-labeled hIL-1β protein. Three clones were randomly selected from the third round of screening, and their nucleotide sequences were aligned with mouse immunoglobulin genes. The single chain antibody genes of the hIL-1β-binding clones were subcloned into the prokaryotic expression vector pET-27b for expression. The molecular mass of the purified anti-hIL-1β single chain antibody was about 28ku. The hIL-1β-binding ability of antibody were examined by ELISA and Western blot assays. Ability of the scFv antibody to neutralize hIL-1β was evaluated by the MTT test. CONCLUSIONS In this study, it is the first time to use the NIPA-based bacteria display system to construct and screen the combinatorial scFv library. Three scFvs against hIL-1β were obtained from the scFv library of the immunized mice. Prokaryotically expressed and purified scFvs demonstrate binding ability with hIL-1β. Among the three clones. The MTT test suggests that scFv-20 is a neutralization antibody against hIL-1β. The study provides a lead candidate for further development of small molecule therapeutic antibodies for treatment of RA.

A recombinant avian antibody against VP2 of infectious bursal disease virus protects chicken from viral infection

A stable cell-line was established that expressed the recombinant avian antibody (rAb) against the infectious bursal disease virus (IBDV). rAb exhibited neutralization activity to IBDV-B87 strain in DF1 cells. The minimum rAb concentration required for inhibition of the cytopathic effect (CPE) was 1.563μg/mL. To test the efficacy of rAb, a 168-h cohabitation challenge experiment was performed to transmit the disease from the chickens challenged with vvIBDV (HLJ0504 strain) to three test groups of chickens, i.e. (1) chickens treated with rAb, (2) chickens treated with yolk antibody, and (3) non-treatment chickens. The survival rates of chickens treated with rAb, yolk antibody and without treatment were 73%, 67% and 20%, respectively. Another batch of chickens was challenged with IBDV (BC6/85 strain) and then injected with rAb (1.0mg/kg) 6, 24 and 36h post-challenge. Non-treatment chickens had 100% morbidity, whereas those administered with rAb exhibited only 20% morbidity. Morbidity was evaluated using clinical indicators and bursal histopathological section. This study provides a new approach to treating IBDV and the rAb represents a promising candidate for this IBDV therapy.

Anchored periplasmic expression (APEx)-based bacterial display for rapid and high-throughput screening of B cell epitopes

We truncated the VP2 protein of infectious bursal disease virus into five fragments: V1–5. All fragments were displayed on the inner membrane of the Escherichia coli periplasm. After disruption of the outer membrane, spheroplasts that had anchored with the VP2 fragment were incubated with an anti-VP2 polyclonal antibody (pAb). Prey pairs were detected and quantitated by flow cytometry with V1, V3, V4 and V5 fragments reacting with the pAb. The antigenicity of all five fragments was analyzed, and our results indicated that epitopes were localized in V1, V3, V4 and V5, consistent with our flow cytometry analysis. Antigenicity analysis of purified VP2 fusion proteins using Western blots confirmed this. Our method provides a rapid, quantitative and simple strategy for identifying linear B cell epitopes.