[Construction and identification of nanobody phage display library targeting Middle East respiratory syndrome coronavirus].

Objective To construct a phage display library of specific nano-antibodies against the Middle East respiratory syndrome coronavirus (MERS-CoV) and apply it to the screening of neutralizing nano-antibodies. Methods MERS-CoV receptor-binding domain (RBD) recombinant protein was used to immunize alpaca. After the last immunization, peripheral blood mononuclear cells (PBMCs) were isolated from the whole blood and total RNA was extracted. The VHH gene was amplified by PCR and used to construct recombinant phages. TG1 Escherichia coli was transformed by these recombinant phages. A phage display library of specific nano-antibodies against the MERS-CoV were obtained and used to screen and characterize the nano-antibodies. Results The volume of this library of nano-antibodies was 1.31×108 and its abundance rate was 5.65×1010/mL. The ratio of VHH insertion in the constructed library reached 96%. There was a rich diversity of nano-antibodies in this library. Nano-antibodies with neutralizing activity were identified and expressed from this library. Conclusion We successfully constructed a library of phages which could be effectively applied to the screening of nano-antibodies against MERS-CoV virus.

Lycopene Prevents Amyloid [Beta]-Induced Mitochondrial Oxidative Stress and Dysfunctions in Cultured Rat Cortical Neurons.

Brains affected by Alzheimer's disease (AD) show a large spectrum of mitochondrial alterations at both morphological and genetic level. The causal link between ß-amyloid (Aß) and mitochondrial dysfunction has been established in cellular models of AD. We observed previously that lycopene, a member of the carotenoid family of phytochemicals, could counteract neuronal apoptosis and cell damage induced by Aß and other neurotoxic substances, and that this neuroprotective action somehow involved the mitochondria. The present study aims to investigate the effects of lycopene on mitochondria in cultured rat cortical neurons exposed to Aß. It was found that lycopene attenuated Aß-induced oxidative stress, as evidenced by the decreased intracellular reactive oxygen species generation and mitochondria-derived superoxide production. Additionally, lycopene ameliorated Aß-induced mitochondrial morphological alteration, opening of the mitochondrial permeability transition pores and the consequent cytochrome c release. Lycopene also improved mitochondrial complex activities and restored ATP levels in Aß-treated neuron. Furthermore, lycopene prevented mitochondrial DNA damages and improved the protein level of mitochondrial transcription factor A in mitochondria. Those results indicate that lycopene protects mitochondria against Aß-induced damages, at least in part by inhibiting mitochondrial oxidative stress and improving mitochondrial function. These beneficial effects of lycopene may account for its protection against Aß-induced neurotoxicity.